Research on the Prevention and Control Methods for Forest Disasters in China’s Forestry Ecological Environment Construction

Yanrong CAI, Xueqing ZHAO, Qiuyu LAI

Abstract With the development of economy， China has gradually begun to pay attention to the protection of the natural environment. Under the concept of "lucid waters and lush mountains are invaluable assets"， importance has been attached to the development of forestry economy. The protection of forest resources and the prevention and control of disasters are important contents and necessary components in the construction of Chinas forestry ecological environment. Through the analysis and research on the types of forest disasters （forest fires， biological disasters， meteorological disasters， geological disasters， deforestation） and disaster-causing factors， some basic countermeasures were put forward with the aim to enhance the production capacity of forest resources， improve the ecological environment of forest resources and prevent forest resource disasters.

Key words Lucid waters and lush mountains; Invaluable assets; Forest disasters; Disaster prevention and mitigation; Basic countermeasures

Received： May 7， 2022  Accepted： July 9， 2022

Supported by National Natural Science Foundation of China （41671283）.

Yanrong CAI （1986-）， female， P.R.China， engineer， masters degree， devoted to the research on soil and water conservation technology.

*Corresponding author. Zhao Xueqing （1995-）， female， P.R.China， engineer， masters degree， devoted to the research on soil and water conservation technology.

Qiuyu LAI （1985-）， male， P.R.China， assistant engineer， bachelors degree， devoted to research on engineering management.

Being the cradle of human beings， green forests are closely related to the earth and human beings. The earth cannot live without forests， and human beings cannot live without forests. As the main body of renewable natural resources and terrestrial ecosystems on the earth， forests play an irreplaceable role in the history of human survival and development. It is the largest ecosystem on land， with various environmental benefits such as water conservation， soil and water conservation， carbon dioxide absorption， recreation， and wildlife protection， and these environmental values are far greater than the economic value of wood. According to the National Forestry and Grassland Administration of China， the forest coverage rate in China was 22.96% in 2020， and the forest area was 220 million hm2. Significant achievements have been made in the protection and management of forest and grassland resources in China. The total carbon storage of forest vegetation reaches 8.98 billion t， the annual water conservation is 628.95 billion m3， and the annual fixed soil is 8.748 billion t[1-3]. Forest disasters have been around China for a long time， and they are becoming more and more serious. At present， China is still a country with a fragile ecology， lacking forests and greenery. The forest coverage rate is far lower than the global average of 31%， the per capita forest area is only 1/4 of the worlds per capita level， and the per capita forest accumulation is only 1/7 of the worlds per capita level. For China， the total amount of forest resources is relatively insufficient， the quality is not high， and the uneven distribution has not been fundamentally changed. Forestry development is still facing huge pressures and challenges， and the main reason is that forest disasters has existed for a long time and become increasingly serious. The protection of forest resources and the prevention and control of disasters are important contents and necessary components to realize the sustainable development of China[4-6].

Concept of Forest Disasters

Forest disasters refer to natural disasters caused by the destruction of forest ecosystems brought about by human activities. Different countries and regions have different forest disasters. The United States is dominated by forest fires， forest insect attacks， forest diseases and bird and mammal damage to; Europe is dominated by wind damage， snow damage and other forest meteorological disasters and forest insect attacks; Japan is dominated by wind damage， snow damage and forest fires; China is dominated by forest pests and forest fires， which pose the greatest threat to forest resources and their losses. In recent years， forest disasters have occurred frequently. According to the national forest data of China， there are 4 major forest disasters， namely： forest fires， deforestation， forest biological disasters and forest meteorological disasters.

Main Types of Forest Disasters

Forest fires

In a broad sense， forest fire refers to any forest fire behavior that is out of human control， spreads and expands wildly in forest land， and brings certain harm and loss to forests， forest ecosystems and humans. In a narrow sense， forest fire is a kind of natural disaster that is sudden， destructive， and difficult to deal with and rescue. Forest fire prevention is an important part of Chinas disaster prevention and mitigation work， an important part of the construction of the national public emergency system， an important guarantee for social stability and peoples well-being， and the foundation and premise of accelerating forestry development and strengthening ecological construction. It is related to forest resources and ecological security， to the safety of peoples lives and property， and to the overall situation of reform， development and stability.

Among the many disasters faced by forests， forest fires pose the greatest threat to forest resources. The out-of-control forest fires lead to the spread of forest fires， which will destroy a large area of forests. Forest fires can be divided into general forest fires， big forest fires， extra big forest fires and particularly extra big forest fires according to whether there is damage to the trees and the size of the burned area （Table 1）.

On average， there are about 10 000 forest fires in China every year， burning hundreds of thousands to millions of hectares of forest， accounting for about 5‰-8‰ of the Chinas forest area. In May 1987， an extra big forest fire broke out in Daxinganling， Heilongjiang province in northern China. The burned area was 1.243 million hm2 with the forest area accounting for 70%， and the wood of 850 000 m3 was burned， resulting in a direct economic loss of about 500 million yuan. In 2010， the "3.12" extra big forest fire in Dali City in southern China had burned an area of 836.35 hm2 and caused economic losses of more than 4.46 million yuan. At about 18：00 on March 30， 2019， a forest fire broke out in Lier Village， Yalongjiang Town， Muli County， Liangshan Prefecture， Sichuan Province of southwestern China. The fire broke out at about 3 800 m above sea level， and because of the complex terrain， steep slopes and deep valleys， and inconvenient traffic and communication， 31 firefighters died in the fire.

Historically， fires caused by wars or human production activities have resulted in huge damage to the forests of the Qilian Mountains in northwestern China. As recorded in Gansuxintongzhi  （New General Annals of Gansu）， in May of the second year of Emperor Yongzheng （1724）， Yue Zhongqi attacked the Xieersu tribe in the east of Qilian Mountain， "set fire to the forest and destroyed the soldiers". The Preliminary Investigation Report on the State-owned Forest Areas in Qilian Mountains of China records： "In the early Qing Dynasty， Nian Gengyao pacified the LuobuZangdanjin rebellion in Qinghai. He sent troops from Lanzhou with the main force directly attacking Xining， the left wing marching via Songpan （Sichuan Province） and the right wing Hexi， then met with the Tibetans to resist the rebellion together. At that time， the forest was thick inside and outside the mountains and it was not easy to attack people. Therefore， the Qing soldiers set fire to the mountains and rushed in from the mountain passes at the north and south foothills. The rebelling people retreated westward." According to the revision of Hexi Chronicle in 1958， from the end of the Qing Dynasty to the eve of liberation of China， in the area of Haxitan in the upper reaches of the Shiyang River， "fires followed the reclamation of wasteland， digging turf and burning ashes， causing forests and grasslands to catch fire quite frequently， sometimes for dozens of consecutive days. Thousands of acres， even ten thousand acres of farmland were burnt out. When the fire broke out， no effort was made to put out it， so the fire burnt freely until it was naturally extinguished." Since the founding of the Peoples Republic of China， governments at all levels in Gansu Province have continuously strengthened the prevention and control of forest fires on the northern slope of the Qilian Mountains. Forest fires have been effectively controlled and no major forest fires have occurred. However， due to the dry climate， there is a large accumulation of combustibles in the forest， and there is also a large amount of dangerous combustibles. Combustibles in forest areas are particularly dry in winter and spring. Once they catch fire， the fire will spread rapidly and have high fire intensity， and it is difficult to put out， making it very easy to cause a forest fire.

The forest and grassland areas with fire danger in the Ningxia Hui Autonomous Region in northwestern China are divided into first， second and third levels according to the forest vegetation type， flammability of main tree species， microclimate， fire source， social status， and the characteristics of forest and grassland fires over the years in the region. The areas with first-level fire danger cover the 3 natural secondary forest areas of Helan Mountains， Liupanshan Mountains and Luoshan Mountains; the second-level fire danger areas range from the 6 counties in the Ningnan Mountains to the state-owned forest farms other than the first-level fire danger area; the third-level  fire danger areas are mainly the economic forests， farmland forest networks and surrounding trees in all counties （cities， districts） in the plain of Ningxia. Therefore， the key areas for forest and grassland fires in Ningxia are the 3 major natural secondary forest areas. The 3 major natural secondary forest areas in Ningxia are the lifeblood of water conservation and the barrier of ecological protection in the autonomous region. Once a forest fire breaks out， the consequences will be unimaginable and will inevitably bring disaster to the survival of the people of Ningxia. Especially in the areas distributed in Helan Mountains and Luoshan Mountains in arid and semi-arid areas， where the forest resources are concentrated， if the natural secondary forest is destroyed， it is impossible to regenerate and restore by man-made and natural forces under the current conditions.

Biological disasters

Biological disasters are natural events that cause harm to human life and property due to improper production and living activities of human beings， destruction of biological chains or excessive and rapid reproduction （growth） of certain organisms under natural conditions. Forest diseases and pests refer to the pathological changes in the physiology， organization and morphology of forest trees caused by pathogenic organisms or abiotic factors such as bad weather and soil. It can lead to poor growth， decline in yield and quality， and even cause tree withering to death and deterioration of ecological conditions.

The occurrence and prevalence of forest diseases in China is relatively serious， and even the forest diseases caused by disasters are affected by abnormal environmental factors and biological damage， which affects the growth of forestry and even causes death. There are 2 918 kinds of forest diseases in China. The forest diseases include mildew and rot， Rhizoctonia solani Kuhn （Sheath Blight）， Agrobacterium tumefactions， Cercospora sojina， Leucostoma cincta， Valsa mali （decay）， powdery mildew， Paulownia fortunei， poplar black spot， anthrax， Pestatotiopsis funerea Stey， apple tree cranker， and walnut shoot-blight. In China， the annual loss from P. funerea is 23.14 million yuan. Apple tree cranker is one of the important diseases of apples， which commonly occurs in all apple producing areas of China. In recent years， the incidence of the disease has been relatively high in the apple orchards in Baoji， Shaanxi Province， and it tends to become more and more serious year by year， resulting in shorter fruiting period， early aging period， and even destruction of the whole orchard with severe diseases. From September 2003 to June 2004， a preliminary investigation was carried out on the occurrence of apple tree rot disease and the severity of the damage in Yangling， Zhouzhi， Liquan， Chunhua， Huangling and other places in Shaanxi. The results showed that tree age was directly related to the occurrence of apple tree cranker disease， and the damage of rot disease gradually increased with the increase of tree age. Pine wilt disease， known as the cancer for pine trees， is a devastating disease of pine trees. Under natural conditions， the disease can harm 45 species of pine. Once a pine tree is infected with the disease， it can die in about 40 d at the fastest， and without human intervention， the pine forest can be destroyed in 3-5 years. Pine wilt disease is a devastating disease， which does harm to the Mausoleum of the Yellow Emperor in Shaanxi.

What are the main virus diseases of apples？ There are more than 20 known virus diseases that can cause damage to apples so far. There are 8 kinds that have been confirmed to be more harmful in production （Table 2）. Apple rot is one of the important diseases of apples， which commonly occurs in all apple producing areas of China.In recent years， the incidence of the disease has been relatively high in the apple orchards in Baoji， Shaanxi Province， and it tends to become more and more serious year by year， resulting in shorter of the fruiting period， early aging period， and even destruction of the whole orchard with severe disease. From September 2003 to June 2004， a preliminary investigation was carried out on the occurrence of apple tree rot disease and the severity of the damage in Yangling， Zhouzhi， Liquan， Chunhua， Huangling and other places in Shaanxi. The results showed that tree age was directly related to the occurrence of apple tree rot disease， and the damage of rot disease gradually increased with the increase of tree age.

Forest pests are insects that harm forests and forest products. There are about 2 400 species of forest pests known in China， of which about 450 species have recorded life histories， habits and control methods. With the renewal of tree species， the change of planting methods and the improvement of management technology， the community and damage degree of insect pests are further intensified. Due to the complex diversity of forest types in China， different ecological regions have the corresponding pests adaptive to the region， with a total number of 5 002 species of forest pests in China. The annual loss of forest growth caused by insect pests is 10 million m3， which is still on rise. Pine wilt disease is a devastating pest and disease of pine trees， and the Monochamus alternatus Hope is its main transmission insect. After the Bursaphelenchus xylophilus invades the tree， the needles of the pine tree lose their luster successively due to the strong pathogenicity of B. xylophilus， and the whole plant dies due to wilting and withering， which can happen in more than 40 d at the fastest. It only takes 3-5 years for a pine forest to be infected and destroyed， so pine wilt disease is also known as the "cancer" of pine trees. Dendroctonus armandi is another kind of pest for pin trees. After infected， the affected tree overflows resin at the intrusion hole， and the wood chips and feces discharged from the insect hole are condensed into a funnel shape. At the same time， the crown of the tree gradually turns yellow， and the tree dies in 1-3 years after infection.

From the 1950s to the 1970s， the forest pests in Ningxia were dominated by large leaf-eating pests such as push moths， inchworms， tusock moths and hawkmoths. However， these insects have the characteristics of small in number， long cycle of occurrence， and being relatively easy to control. With the use of chemical pesticides， the status of these insect species have gradually receded in Ningxias forest insect system. The pests which have occurred frequently are those with small size， fast reproduction and large number， mainly scale insects， and some "hidden" pests like various trunk borers， branch borers and leaf miners mainly including longicorns， buprestid beetles. These two types of pests are difficult to control because of their large numbers and strong concealment. The most destructive ones in the whole region are "first beetles， second scales and third longicorns" （namely， Melanophila decastigma Fabr， Quadraspidiotus gigas Thiem， Eulecanium kuwanai， Saperda populnea L.， Anoplophora glabripennis Motschulsky and Anoplophora nobilis Gangibaeur）. By the end of the 1980s， A. glabripennis and A. nobilis swept the entire autonomous region， almost destroying the forest network of the first generation in Ningxia， causing huge economic losses， and severely damaging the ecological environment of Ningxia， which greatly affected industrial and agricultural production， and caused a huge negative impact on the production and life of the people. In 2016， the results of the forest resources inventory showed that less than 10% of Ningxias forests had good ecological functions， the sub-healthy and unhealthy arbor forests accounted for more than 40%， and the insect pests were in a high and frequent situation. The spreading trend of pests such as Eucryptorrhynchus scrobiculatus Motschulsky， and Cydia pomonella， which cause continuous damage to Ningxias forest resources， has not been effectively controlled， but the risk of the introduction of alien pests has increased， speeding up the spread of pest damage. In 2018， pests invaded a total area of 6 600 hm2 in the whole forest system of Shaanxi. Poplars are widely planted in cities， highways， and parks across China， and in the shelterbelts and farmland shelterbelts in the Three Norths （in northeast， north and northwest China）， covering an area of 6.7 million hm2. However， Stilprotia salicis， A. glabripennis， A. nobilis and Gypsonoma minutana Hubner are quite common to the polar in the above areas. Due to unreasonable pruning of branches and leaves， ignorance of the prevention and control work， and few special machinery and equipment， the rate of pest damaged trees reaches 60%， and in some places it is as high as 80%.

Rodent disease includes forest rodent diseases and crop rodent diseases. For example， there are about 160 kinds of rodent diseases in forests， and more than 160 kinds of rodents in crops （the 2 have similar species of rat species）. This is a perennial disaster suffered by forests. The annual loss of forest is equivalent to about 300 million yuan， and the national forest rodent damage area is 1.5 million hm2. In China， forest rodent damage mainly occurs in the west of northwest China and north of north China， where the ecology is poor. In 1987， the area of rodent disease caused a damage of 5 000 hm2 to the forest area in the Inner Mongolia， and the average in recent years was 8 000 hm2. In Minqin， Wuwei and other places in Gansu， the great gerbil caused serious damage to shrubs and the main sand plant Haloxylon forest， with a damage rate of 67%. In Puxian Forest Farm， Shanxi Province， from winter to spring， when the grass germinates， the average damage rate caused by Myodes rufocanus biting reaches 50%. Young trees are girdled to death， and 90% of the Manshan forest farms have been destroyed. The rats not only compete with livestock for food， but also caused secondary bare land in the forest area due to excavation activities， reducing forest productivity and deteriorating ecological environment. Forest rodent disease is one of the main threats to Ningxias forestry construction. From 2014 to 2020， its occurrence area and damage degree were no less than those of pests. Rodents with serious damage mainly include Eospalax rothschildi， Myospalax smithii Thomas， Microtus fortis， Dipus sagitta， Allactaga sibirica and Citellus dauricus， among which E. rothschildi and D. sagitta do the most serious damage， and they are mainly distributed in Yuanzhou District， Jingyuan， Haiyuan， Pengyang， Xiji， Longde， Yanchi， Tongxin Mountains （the 8 counties in Guyuan City）， and the wetland depressions in the Yellow River Diversion Irrigation Area. Many woodlands have been damaged for many years， and there are few trees left， resulting in a great waste of manpower， material and financial resources， and serious damage to vegetation， further causing soil erosion， resulting in the decline of plant communities.

Meteorological disasters

Drought： it is the most widespread meteorological disaster in China. The most notable features are high frequency， wide distribution， and rhythmic changes. Drought is extremely detrimental to forestry production. Drought is a common meteorological and physiological phenomenon in the growth process of various plants. The right amount of water control can help the root system of the seedlings go deep into the ground， so that the seedlings are strong but not prosperous. But if it is too dry， the seedlings will die of losing water. Drought can inhibit the growth of seedlings. When it is too dry， the life and metabolic activities of plants will be affected， which often causes plants to temporarily stop developing and even lead to plant death. Therefore， water control should be reasonable. Drought can cause root hairs to thin out. If it is too dry， the root system， especially the root hairs （effectively absorbing roots） will become thin， reducing the effective roots， and thus the absorption function and the tree vigor weaken. Drought can cause plants to dehydrate and die. Excessive drought often causes damage to plant cells， make them lose physiological functions， and lead to dehydration of cells， resulting in high temperature sunburn and dehydration and death of seedlings. The construction of the "Three Norths" shelterbelt is undoubtedly an effective measure to improve the ecological environment in the northwest region of China. Due to the early dry season and little rain， the survival rate of afforestation is extremely low. According to surveys in Ningxia and Shanxi， in the past 10 years， people in this area have continuously planted trees without seeing the survival of trees， and people have been struggling to use cars to pull water to water the trees， but the summer drought causes so many seedlings to die that only 450 seedlings can survive per hm2， with some areas even left with no seedlings. In Guangling， Shanxi Province， where the drought is severe， 9 450 hm2 of saplings were planted， the survival rate was less than 60%， and the planted area accounted for 91%. In Dizhuang Village， Shanxi Province， 133 hm2 of larch was planted in spring， but all withered to death because of the summer drought. Based on the situation in all parts of Shanxi， the impact of drought on forestry production is mainly reflected in the following aspects （Table 3）.

Wind disaster： it includes the disasters caused by tornadoes， thunderstorms with strong winds， cold waves with strong winds， typhoons. Wind disasters are an important type of forest disaster in China. During the wind disaster comes， the damage to the seedlings becomes even more serious. On May 5， 1993， the northwest China was attacked by the "Heibao" （black storm）. All 18 000 hm2 of fruit trees in Xinjiang， Gansu， and Ningxia were destroyed. The survival rate of the newly planted trees was close to zero. All the same， 278 km2 of trees in Taole， Ningxia were all destroyed， and the surface wind eroded 3-5 cm， causing a direct economic loss of 500 million yuan. In recent years， the weather has been bad， and almost every year in the growing season of apple trees， there are strong winds or strong winds accompanied by heavy rain. In mid-June 2014， the Baoji area of Shaanxi suffered 2 consecutive attacks of strong wind at the scale of 6-7， and some sapling apple trees were blown down by the wind. After investigation， it found that the sapling trees that were blown down were mainly Gala varieties， and the trees were blown off from the grafting joint. After research and analysis， 3 main reasons were suggested： First， the branches of Gala series varieties were brittle with poor flexibility， and are easy to split. Second， the canopy of the newly-hanging fruit trees had not been fully expanded， and the orchard was more spacious and unblocked than the mature orchards. The third is that the grafting joints of the newly-hanging fruit trees are not fully healed. In addition， the fruiting trees were heavy at the top， making them easy to be cracked by the strong wind from the joints. In the middle and late stages of fruit growth， the phenomenon of strong wind blowing off the fruit is more common， which is basically seen in all major apple producing areas in China. The degree of production reduction varies with the wind force. Therefore， in the growing season of fruit trees， speical attention should be paid to the early prevention and countermeasures to protect the fruit trees according to the climatic characteristics of various places， especially in areas with strong winds in previous years. On August 15， 2018， a tornado hit Hekou District， Dongying City， Shandong Province， and the apple orchards in the entire region were attacked. Most of the apple trees were uprooted， all the fruits fell off， and more than 95% of the apples were lost. Strong winds often bring many adverse effects to the growth and development of apple trees. After investigation， it is known that the wind at the scale of 6-8 can affect the flowering and pollination of apple trees， damage leaf organs， blow down fruits， and cause crown deflection and even blow down the trees.

Snow disaster： moderate snowfall in winter can make trees survive the winter， increase soil moisture， freeze pest damage， reduce dust in the air， reduce air pollution， and promote human health. However， for 10 consecutive days， or even dozens of days， heavy snow fell continuously， resulting in excessive snow accumulation， which will not cause harm to forestry for a long time. Due to excessive snow and deep snow cover， the normal growth of forests is affected. Although snow disasters are not harmful to forests in China， they often cause huge economic losses when people lack preparation and cannot respond to emergencies. In 1990， in order to revitalize the local economy， Yanan area imported more than 20 trucks full of jujube saplings and apple saplings from Guanzhong. Due to the sudden heavy snowfall， the saplings were not used for a long time. In 2010， due to the combined influence of the eastward-moving cold air in Xinjiang and the southwesterly air flow， freezing weather occurred in most parts of the inland Shaanxi Province from April 11 to 14. Xian experienced "Blow Snow in April" that had not been seen in 49 years， and 20 counties in the province experienced the lowest temperature in the same period in mid-April since 1961. The weather event severely affected most of the fruit trees in their budding， flowering and young fruiting stages in Shaanxi. According to released official data， a total of 211 townships （towns） in 22 counties （districts） in Shaanxi Province were affected， with a population of nearly 4 million. Pear trees， apricot trees， peach trees and apple trees were severely frozen in most areas， among which， the area of apples suffering from freezing damage to varying degrees exceeded 67 000 hm2; the damaged area of kiwifruits was 20 000 hm2; and pears was 8 000 hm2. In some areas， production dropped by more than 90%. Shaanxi Province is the second largest fruit producing province in China. In 2009， the fruit planting area in the province reached 1.011 3 million hm2， with a total output of 11.5 million t， of which the total area of apples reached 570 000 hm2， with an output of 8.1 million t; the area of kiwifruit reached 40 000 hm2， with an output of 500 000 t. With the planting area and output ranking first in China， the apple output of Shaanxi also accounts for 1/8 of the worlds total output. More than 80 countries and regions in the world have become the main sales destination of Shaanxi fruit.

Frost： Frost is a frequent disastrous weather in China， mainly occurs between September and May of the following year， with an average of 2-4 times a year， and it is a serious threat to forestry production. During the Qingming Festival in 2018， a frost that was said to be rare in 50 years swept the Shaanxi-Gansu region （the main apple producing area of the northwest）. It was the flowering period of late-ripening Fuji， and many fruit flowers were directly frozen and withered. Since apples are produced once a year， it had a great impact on the production of apples in the 2018-2019 season， and the supply and demand situation was out of balance， resulting in a shapr rise of apple futures. Data shows that apples rose from 6 400 yuan/t during the Qingming Festival to 9 400 yuan/t， an increase of 47% in more than one month， which attracted great attention from the society. The followed investigation found that Mae Town， Sanyuan County， Shaanxi Province was located in the low-lying terrain between Lingqian Town and Yaozhou District， Tongchuan City， making it severely suffered from the frost. According to a fruit farmer who was bagging in the field， he "plants 0.267 hm2 of Red Fuji and 0.133 hm2 and early-ripening apples， 1 500 fruit trees/hm2. The annual yield of Red Fuji is 52 500 kg/hm2 in normal years， and because the local fruit trees are irrigated by well water， they are generally too large， and the water content is good but the hardness is not ideal. At present， the early maturity has been completed. The late-ripening bag is about to start， and the late-ripening Fuji is just at the critical period of flowering during the Qingming Festival. The low-lying terrain together with the early flowering makes frost easy to sink， resulting in heavy losses with a yield reduction of more than 50%". The field investigation showed that most apples were small or were secondary fruit， and there were few fruit trees bearing on the fruit trees.

Hail disaster： It is a small-scale weather system with strong regional characteristics. China is one of the countries with the most serious hail disasters in the world. The annual economic losses caused by hail disasters to forestry reach 1 billion yuan. In May 1993， there was a sudden hailstorm in Qianyang， Longxian and other places in Shaanxi Province， and the hail had a diameter of 1cm and the largest one like a fist. Fruit trees and mulberry trees were severely damaged and suffered heavy losses. The prickly ash trees that were to harvest were smashed into bare poles. Accompanied by strong winds of level 8 or above， the hail disaster came with a sudden and affected a large area， which made 270 000 hm2 of apple trees fail to harvest， and 450 000 hm2 of apple trees affected， with the damage rate reaching 54%. The loss of mulberry trees was even greater. May was the peak period of sericulture. Due to the destruction of mulberry trees and insufficient supply of mulberry leaves， farmers could only sell silkworms at a low price. According to preliminary statistics， each sericulture household earned 500-1 000 yuan less. The apple production in Gansu Province accounts for 8.6% of the national production. The apple planting areas in the province are mainly concentrated in Pingliang， Tianshui and Qingyang regions. According to statistics from China Apple Network， the apple production in these 3 regions can account for 94% of the provinces production. From the afternoon to the night of June 10， 2018， a heavy storm and hail weather hit Longnan， Tianshui， Pingliang， Dingxi and other areas in central and eastern Gansu province. The hail lasted for more than 20 min in some areas， and many crops were seriously damaged. This hailstorm affected the main apple producing areas in Gansu. In addition to directly affecting apple production， hail also affected the yield of quality fruit， which was even worse for the apple market， which was already shrouded in the turmoil of production reduction. The worries about production cuts market rises again.

Geological disasters

There are many kinds of geological disasters in China. The one that can cause direct damage to forestry is mainly landslide flow， especially debris flow， which has a strong impact force and can exert a force of several thousand Newtons per m3 on the objects on the flow path. Wherever the landslide happens， the thick trunk is cut off in the middle， and the smaller shrubs and herbs are more easily impacted or seriously buried. Landslides and collapses are the main hazards to the countryside， because they can harm people and animals， destroy forests， roads as well as the agricultural machinery facilities， water conservancy and hydropower facilities， and sometimes even cause devastating disasters to the countryside. The former Czechoslovakia conducted a national census of landslides in 1961-1962， finding that the landslides destroyed 13 500 hm2 of forest. In June 1989， a large-scale landslide occurred in the Changwu section of the Xilan Highway， and a 1.2 hm2 peach orchard was completely destroyed. The Qilian Mountains are one of the areas prone to geological disasters in China. Sudden disasters such as collapses， landslides， and mudslides have great destructive effects on local forests， forestry production such as closing mountains to facilitate afforestation and seedling cultivation， as well as production facilities such as the roads in forest areas. In Tanshanling forest area of the ancient city protection station， the goaf of the coal mine caused the forest land to collapse， and the trees fell and died. Potential dangers of ground subsidence also exisited in the Jiutiaoling Coal Mine in the jurisdiction of Xiying River Protection Station and the coal mine goaf in the jurisdiction of the Kangle Protection Station. At 5：00 am on September 17， 2011， a landslide occurred to a 300-meter-long mountain in Wulonggou， north of Zhaozhuang Village， Xinyang Town， Maiji District. The disaster resulted in the destruction of 2.4 hm2 of arable land and 3 hm2 of orchards in Zhaozhuang Village. The pouring soil filled the river channel under the mountain instantly， forming a hill with a height of more than 10 ms， a length of about 200 m and a width of about 100 m. The mountains at the east and west ends of the landslide point were connected together， which blocked the river water， forming a dammed lake， threatening the safety of thousands of villagers from 180 households in Zhaozhuang. On July 20， 2020， due to continuous rainfall， a landslide occurred in Taiping Town， Konggang New Town， Xixian New District， with a total volume of more than 5 000 m3， causing 2 hm2 of orchards to be buried. The landslide point was located on a 50 m-high soil rise in Taipingbao Village and Chen Panwan Village in Taiping Town. After this round of rainfall began， the rainwater on the plateau collected in the ditch. The sediments from the upstream villages and the collapsed earthwork were mixed together and rushed out from the mouth of the ditch， burying the orchard. The debris flow was less than 20 m from the nearest house， and the dirt on the road once exceeded 30 cm.

Deforestation

Every year， 10 million km2 of forests are deforested， and 9 million km2 of forests are destroyed in the world. Deforestation refers to the uncontrolled， unplanned and unreasonable logging of forests. The consequences of this behavior will lead to damage to forest ecosystem services and exacerbation of problems such as global warming. In ancient times， the virgin forests of Gansu were extremely lush. However， due to the long historical process of unrestricted deforestation and arbitrary logging， the virgin forests of Gansu have changed drastically， leaving bare hills without trees. The consequence is that the climate is unbalanced， floods， droughts and sandstorms are frequent， and peoples lives are becoming increasingly difficult.

According to the data， forests and grasslands grew luxuriantly on the plains， mountains， hills， and plateaus in the southeastern part of the Loess Plateau during the Western Zhou Dynasty， and the forest vegetation coverage rate was as high as 53%. With the invention of iron tools， the level of agricultural productivity continuously improved， and the population gradually expanded. In order to meet the needs of life such as reclaiming farmland， building houses， cooking food， and burning charcoal for heating， the degree of human destruction of vegetation continued to increase， resulting in the continuous decrease in grass vegetation coverage. During the Spring and Autumn Period and the Warring States Period， iron tools were widely used. The Guanzhong Plain in the southern Loess Plateau and the plains in the middle and lower reaches of the Fen River were reclaimed into arable land， and the forest and grassland vegetation in the valley plains were gradually replaced by arable land. From the Qin and Han dynasties， agriculture on the Loess Plateau continued to advance to the north and west， and the original woodlands and grasslands were transformed into farmland one after another. By the Southern and Northern Dynasties， the forest coverage rate of the Loess Plateau was about 40%. By the Tang and Song Dynasties， the forest coverage rate dropped to about 33%. By the Ming and Qing dynasties， the population further increased， and the forest and grass vegetation was further reclaimed as farmland， and the forest coverage rate dropped to about 15%. From the end of the Qing Dynasty to the beginning of the 20th century， a large number of people entered the mountainous areas in the hinterland of the Loess Plateau to clear forests and open up wasteland to escape the war. In the early days of the founding of New China， the forest coverage rate was only 6.1%.

As we all know， vegetation has the functions of water conservation and water conservation. Due to the reduction or even disappearance of vegetation due to man-made destruction， the Loess Plateau， which has loose soil， has lost the protection of vegetation and caused soil erosion. The Loess Plateau is also located in the monsoon climate zone——rain hot during the same period. The relatively large surface runoff formed by torrential rains from July to August each year accelerates the erosion of the flowing water due to the large undulating terrain， and finally forms the criss-crossing and fragmented landform features of the Loess Plateau. Therefore， starting from the Qin and Han Dynasties， the ravines on the Loess Plateau have been formed for more than 2 200 years， and the soil erosion of the Loess Plateau aggravated in the subsequent dynasties due to wars， population migration， so that about 1.6 billion t of sediment flow into the main stream of the Yellow River， making the soil more and more barren.

The main reasons for the deforestation in China are as follows： First， the land has changed hands. When the first round of land contract expired， due to the death of the original contractor or the change in the ownership relationship between the villagers and the land， the land changed owners， and there was no consensus on the price of forest trees， resulting in excessive deforestation. The second is policy mistakes. When the first round of land contracts expired， the contract extension policies formulated by some localities were inconsistent with the central governments policy of "major stability and small adjustments"， which harmed the interests of farmers and led to excessive deforestation. The third is profit-driven. Woodware processing factories in some areas raise the purchase price， which makes some farmers only focus on their immediate interests， only pay attention to economic rights， not the obligation to protect the environment， and indiscriminately cut down trees or forests on the original contracted land. The central government of China has repeatedly reminded that in the process of the second round of land contracting， it is necessary to prevent the phenomenon of deforestation. However， some places still ignore the overall situation， leading to deforestation.

Basic Countermeasures for Forest Disaster Prevention

Forest disasters are the result of the combined effect of nature and humans， and the product of the imbalance of ecological development. People should understand it correctly， establish awareness of disaster prevention， and take precautionary measures. It is necessary to actively formulate various measures to prevent the occurrence and development of disasters， strive to turn large disasters into small disasters， strengthen the peoples awareness of disaster resistance， and achieve effective disaster resistance and disaster prevention all year round， so as to reduce passive coping and helplessness， and reduce disaster losses to minimum.

Scientific formulation of plans

Forestry construction is a fundamental issue related to sustainable economic and social development. Since the "13th Five-Year Plan"， the Central Committee of the Communist Party of China and the State Council have attached unprecedented importance to forestry construction， the masses of the people have unprecedented expectations for a good ecology， and forestry has never undertaken the unprecedented historical responsibility of green development. Moreover， major achievements have been made in the protection and restoration of 3 systems and 1 diversity （namely， forest ecosystem， wetland ecosystem， desert ecosystem， and biodiversity of wildlife and nature reserves）， and the development of ecological forestry and livelihood forestry. Standing at a new starting point， shouldering new missions and facing new challenges， Chinas forestry industry has entered a new stage of promoting modernization. Therefore， efforts should be made to formulate scientific plans in the following ways.

Always insist on improving ecology as the fundamental direction of forestry development

To protect the ecological environment is to protect productive forces， and to improve the ecological environment is to develop productive forces. It should adhere to the priority of protection and natural restoration， stick to both quantity and quality with quality coming first， strengthen the construction of forest ecological security， speed up the process of land greening， carry out ecological management of mountains， rivers， forests， fields and lakes， conduct forest city construction， enhance scientific management of forest ecological resources， and comprehensively improve the stability and ecological service functions of natural ecosystem.

Always insist on strengthening the industry as a powerful force for forestry development

Clear waters and lush mountains are invaluable assets. Thus， it should give full play to the important functions of forests as reservoirs， banks and grain depots， deeply understand the dialectical relationship between ecology and industry， public welfare and economy， develop forestry features and emerging industries， transform and upgrade traditional industries， and enhance the vitality of forestry development， so as to achieve targeted poverty alleviation in forestry， create and accumulate ecological capital and green wealth on the land， and promote green wealth for the country and green benefits for the people.

Always insist on protecting resources and maintaining biodiversity as the basic tasks of forestry development

It should comprehensively protect natural forests， wetlands， and sandy vegetation， as well as the diversity of typical ecosystems， biological species， and genetic genes， implement forest quality improvement projects， and strictly protect woodlands and wetlands. Attention should also be paid to accelerating the rescue and protection of rare and endangered wild animals and plants， building national parks， and strengthening the management of import and export of wild animals and plants. Efforts are needed to cultivate ecological values of citizens and promote harmonious coexistence between man and nature.

Always insist on reform and innovation as the key driving force for forestry development

Efforts should be made to strengthen the top-level design of forestry reform， improve the management system of state-owned forests and collective forests， innovate property rights models， and extensively mobilize the initiative and creativity of the whole society to develop forestry. It also needs to give full play to the leading role of scientific and technological innovation， realize the transformation from factor-driven to innovation-driven， promote mass entrepreneurship and innovation， continuously release reform dividends and innovation dividends， and comprehensively improve the ecological， economic and social benefits of forestry.

Always adhere to the rule of law as a reliable guarantee for forestry development

Accelerate the scientific and democratic legislation of forestry， strengthen forestry law enforcement and popularization， form a complete forestry legal normative system， an efficient legal enforcement system， a strict legal supervision system， and a strong legal protection system， protect property rights， regulate public rights， and continuously improve forestry Governance system and improve governance capacity.

Always adhere to open cooperation as an important path for forestry development

Taking the international implementation of conventions and cooperation and exchanges as a platform and the "Belt and Road" Initiative as an opportunity， efforts are needed to deeply participate in the global response to climate change， forestry cooperation and ecological governance， actively serve the overall political and diplomatic situation of the country， and coordinate both international and domestic resources and markets to form a new pattern of opening up in overall forestry， so as to make new contributions to maintaining global ecological security.

Find out the current situation of forest resources and mastering their production characteristics Only through figuring out the current situation of forest resources and mastering their production characteristics can we adapt measures to local conditions， give full play to advantages， make rational use， weaken disaster-causing factors， and reduce disaster losses. According to different types of forest conditions， different cutting standards should be formulated to make the best use of the land and the forest. In the interlaced area of forestry and animal husbandry， a coordinated development mechanism combining forestry， farming and animal husbandry should be established to form a reasonable and high-function complex ecosystem， while in areas with severely degraded forest land， closing mountains for forest cultivation and prohibiting grazing should be promoted. In areas far from living areas and lack of water sources， some charcoal trees can be planted according to local conditions， and in suburbs with good traffic and environment， it can implement the principle of combining trees， shrubs and flowers to get the best ecological and social benefits.

Adhere to the principle of balancing quality and quantity

Based on the principle of taking both quantity and quality into consideration， efforts should be made to improve low-quality tree species， reduce resource consumption， and increase the output of forest products. In short， reasonable and flexible forest land use indicators should be worked out according to different forests， different types of tree species and different environments， so as to gradually change the natural economic mode of using without management and with little management into the scientific and rational forest land resources use mode that combines uses with management， thereby promoting the continuous development of the forest ecological environment in the direction of high efficiency and balance.

Improving the level of science and technology

With the acceleration of research on forest resource disasters， it can be expected that a new scientific system — the scientific system of forest ecological disasters will inevitably develop. Therefore， scientific research units and colleges and universities should conduct advanced research on this scientific system， clarify the research objects and goals， and plan the research content， which will undoubtedly promote the development of forestry disaster reduction. The science of forest disasters is a marginal scientific system cross forestry sciences and， social sciences and human sciences that focuses on the study on the characteristics， laws， causes， and development trends of forest resource disasters， as well as engineering and non-engineering measures to reduce forest resource disasters.

The basic framework of forest disasters is still not perfect， mainly composed of man-made disasters （fire， deforestation， three waste pollution — wastewater， exhaust gas and solid waste）， biological disasters （diseases， pests， rodents） and atmospheric disasters （wind， hail， drought， cold， flood） and  geological disasters （debris flow， landslide， collapse and soil erosion）. The research objects are divided into the following main disciplines： meteorological disasters， marine disasters， hydrological disasters， geological disasters， biological disasters， environmental disasters， astronomical disasters， which involves all aspects of nature and society. Therefore， in order to make the scientific system of forest resource disasters develop healthily， in addition to having a broad and solid foundation and profound knowledge， there must also be the guidance of systematic scientific thought and the spirit of coordination and mutual cooperation. Therefore， it is necessary to emphasize the combination of macroscopic research and microscopic research， natural science and social science， empirical research and experimental research， time factor and space factor， inorganic factor and organic factor， life factor and non-life factor， theoretical research and practical application， single discipline-oriented research and cross， comprehensive and systematic research. Under the guidance and development of system science， forest disaster research will show a vigorous development trend.

For forest diseases， prevention and control should be the main priority， and comprehensive management should be carried out. At present， the commonly used control measures are mainly applied to nurseries， young forests， economic forests， shelter forests， landscape forests and garden greening trees. It is difficult it is difficult to take professional control measures for virgin forests and general mature forests， because of their tall trees， wide areas， and often remote locations. Control methods include strengthening quarantine （plant quarantine）， forestry control， chemical control and breeding disease-resistant tree species. Among them， the purpose of forest control and prevention is to maintain the vigorous vitality of the forest through improving the management level， which is the fundamental measure to prevent and control diseases. Its main contents include building mixed forests with suitable tree species at the proper place， timely breeding， removing diseased trees and diseased branches and leaves， and timely detection and removal of the origin of the disease are the key to preventing the spread of diseases. Wildfires， grazing， and random skin scraping are important incentives that cause mechanical damage to trees and cause bacteria to invade from wounds， all of which should be prohibited or restricted. In addition， removing the intermediate host of rust bacteria around the woodland and nursery can achieve the effect of preventing and controlling tree rust under certain conditions. In production practice， it can prevent disasters and maintain ecological balance to the greatest extent by taking forestry as the basis and combining with other measures， which should complement each other.

Reducing forest disasters is， in an economic sense， essentially the same as increasing production. However， for a long time， due to the low investment in the production industry that mainly consumes biological resources， it is believed that such renewable resources are "inexhaustible"， resulting in many forest resource disasters. In terms of management， the forests have been greatly suffered from excessive logging， with much attention being paid to using the forest resources but little attention to tending the forests. Although afforestation was advocated in the late 1970s， attention was only paid to planting trees but not to managing， so that the trees were planted every year， but there were few trees left every year. It is a common phenomenon that people are skilled in calculating the income of timber and ambiguous about the loss of forest resources. As a result， the awareness of disaster reduction from awareness to action is far from keeping up with the objective development of forest disasters， which is an important reason for the increase in forest disasters.

According to the painful lessons of the heavy economic losses caused by forest fires in Daxinganling and Hulunbuir League， Inner Mongolia， it is necessary to establish the concept of equal importance to disaster control and production increase. When formulating forestry planning and developing community economy， disaster factors must be fully considered， and disaster reduction should be incorporated into social and economic development planning and production promotion. When evaluating forestry benefits， it is necessary to estimate the losses caused by disasters， take the disasters as national conditions， and seek greater economic benefits from disaster reduction.

Disaster reduction is a systematic project， which should play a leading role in science and technology. It is necessary to carry out comprehensive monitoring and forecast， and strive to coordinate forest disaster control plans and comprehensive disaster zoning; conduct comprehensive research on disaster resistance capabilities; appropriately introduce foreign new technologies; and explore comprehensive disaster reduction management models. Efforts should be made to cultivate forestry industry professionals and management personnel， strengthen practical skills training for forestry industry practitioners and farmers， and comprehensively improve the overall quality of forestry industry operators. In the process of forestry industrialization development， forestry science and technology departments at all levels should actively provide individual and private foresters with technical services on forest protection and fire prevention， forest disease and insect pest forecasting， prevention and control， and seedling breeding， as well as other related forestry technical training in line with the principle of "active support， technical guidance， supporting services， and standardized development."

Establishing a sound disaster prevention system

The disaster reduction work in Chinas forest industry started from scratch and has gradually been carried out. All regions have successively established forest protection and fire prevention headquarters， forestry extension stations， forestry pest control and quarantine stations， forestry public security agencies， and wildlife protection agencies. Governments at counties （cities， districts） levels have also established corresponding institutions， and townships （towns） have established forestry workstations. However， in recent years， man-made disasters， biological disasters， geological and meteorological disasters are still on the rise. Therefore， the following measures should be taken.

The first is to increase the publicity of disaster reduction. The virtuous cycle of forest ecological environment is a grand systematic project and a fundamental measure to reduce the disasters of forest ecology. It is necessary to rely on the joint efforts of all the people to carry out publicity and education， and raise the ideological awareness of the people through multiple channels. Thus， the following measures must be taken： ① Coordinate the relationship between people and forests， vigorously develop human resources， adjust the behavior of human beings to exploit and utilize nature， improve the quality of life， and realize the all-round development of human society. ② Enhance the awareness of "cherishing forests" among all people， and make use of the "Arbor Day" on March 12 every year to carry out tree planting activities for all people， so as to make people fully understand the basic national conditions that China has large population and few forests and insufficient forest reserve resources. ③ Strengthen the ecological concept of cadres at all levels and the masses， take the forms of oral explanation， print publicity， typical guide and image education to popularize forestry knowledge and enhance forest protection awareness. ④ Cultivate a group of native forestry technical teams using the vocational and technical colleges， party schools， broadcast and television schools， vocational middle schools， agricultural correspondence universities， peasant night schools and modern distance education sites. ⑤ Strictly implement the Forest Law of the Peoples Republic of China， so that there are laws to abide by， laws must be followed， law enforcement must be strict， and violations must be investigated. ⑥ Strive to achieve good effects on external publicity， introduce Chinas forest disaster prevention experience to foreign countries， expand the exchange of forestry disaster prevention with foreign countries， and appeal to foreign advanced experience. ⑦ Emphasize disaster reduction education for preschool children and popularize the knowledge of forestry disaster reduction.

Second， the work of forest protection and fire prevention should follow the policy of "prevention first with active elimination". ① Establish and improve forest protection and fire prevention regulations and organizational structures， implement the administrative leadership responsibility system， and take various effective measures to enhance the cadres understanding of forest fire hazards. ② Step up the construction of fire protection engineering facilities through acting according to local conditions and setting up defence according to the disasters. ③ Strengthen the management and control of fire sources， and strictly control the use of fire in the wild during the fire danger period. ④ Actively set up fire lines， build evergreen broad-leaved fire forest belts that have been successfully tested， and incorporate them into afforestation planning and design， which should be implemented and accepted simultaneously （The area of coniferous artificial forest in the distance separation of fire belts shall not exceed 80 hm2）. ⑤ Reserve the evergreen broad-leaved tree and shrub forests or forest stands with both fire prevention and soil and water conservation properties around the planting site during afforestation. ⑥ Establish and improve the professional team of forest protection and fire prevention， and improve the professional quality of the team.

The third is to adhere to the principle of "prevention first， in a comprehensive way." ① Establish and improve the forest pest control system， and strive to make good predictions and forecasting. ② Strengthen plant quarantines and strictly prevent the transmission， spread and expansion of foreign dangerous or destructive pests. ③ Vigorously advocate biological control and keep natural enemies. ④ Make rational use of pesticides， and good selection of non-toxic， high-efficient drugs that have short residual period. ⑤ Take the technical measures of forestry management as the basis， and carry out strict scientific management in the forest area for all aspects of forestry production， such as selecting improved seeds， cultivating strong seedlings， creating mixed forests， so as to improve the growth environment of forest trees， enhance the defense ability of forest trees， thereby achieve the goals of controlling forest diseases and insect pests， and ensuring the healthy growth of forest trees.

Fourth， as for forestry meteorological disasters and geological disasters， the forestry department should work with the departments of geology， meteorology， water conservancy， agriculture， geography， technology， and society to study their occurrence laws， improve the level of forecasting， overcome key and common technical difficulties in disaster reduction， and give full play to the overall functions of monitoring， reporting， resistance， defense， rescue and assistance. Only by combining the above-mentioned factors and exerting them comprehensively， organically and jointly， can the current situation of low disaster reduction efficiency be improved. Moreover， a national unified forestry disaster information system must be established as soon as possible.

Fifth， deforestation shall be strictly prohibited in the forest to open up wasteland， and the hillside fields with a slope of over 25 should be afforested into forests and grazing; deforestation， quarrying， sand mining， soil mining and other deforestation activities shall be prohibited; firewood cutting and grazing in young forest land and special-purpose forests shall be prohibited; except for education， the one with serious deforestation behaviors shall be dealt with according to the relevant regulations in criminal law; the logging permit system shall be adhered to， the logging with certificates shall be implemented， and the examination and approval department shall not go beyond its authority.

The sixth is to achieve full coverage of forest inspections. In 2019， 72 517 cases of forest destruction were investigated and handled， and more than 3 500 illegal cases of various grassland abuses were investigated and dealt with according to the law. Special operations shall be carried out to severely crack down on illegal and criminal activities that destroy wild animal resources such as birds and smuggling of wild animals and plants such as ivory.

Strengthening investment in afforestation （forest land construction）

It is a long-term construction cause of the whole people to plant trees， green the motherland， realize the gardening of the land， and improve the virtuous circle of the natural ecological environment， and it is a great cause that benefits the present and future generations. Due to the dual nature of forestry disaster reduction work， disaster reduction should be based on expanding forest area and improving forest ecological benefits. Appropriate and quality seedlings are the basic link of forest disaster reduction; afforestation project and strict management are the guarantees to improve the survival rate. In the selection of tree species and forest species， the soil-rocky mountainous areas shall be dominated by timber forests， which can conserve water; plains and basins shall be dominated by farmland shelter forests with four-side planting; in dry  areas， where attention is needed for gully protection and water source protection， forests for soil and water conservation shall be vigorously developed; the hilly areas shall also be dominated by water and soil conservation forests， and in wind-sand areas， wind-proof and sand-fixing forests shall be mainly used. Tree species must be adapted to the natural conditions of afforestation and must be in line with business purposes， and their value and use must be considered. In afforestation， it is not only necessary to select suitable tree species with high sustainable value， but also to do a good job in matching tree species. Therefore， efforts should be made to strengthen investment in forest land construction.

The long-term heavy logging and light construction of forest land is an important factor for the aggravation of forest land disasters. The forest land area is 2.5 times that of 120 million hm2 of arable land， and there are nearly 40 million hm2 of wetland and 53.3 million hm2 of usable sandy land， which is a huge biological gene pool. It plays an important role in supporting the improvement of peoples living standards in the future. Facing the current situation of forest land， it is necessary to strengthen forest land construction， increase construction investment， set up special forest land construction funds， establish high-quality， high-yield and high-efficiency artificial forests， improve forest disaster-bearing capacity， and lay a solid material foundation for the modernization of forestry， agriculture and animal husbandry. Forestry construction should be based on infrastructure first， together with the simultaneous development of virgin forest land and artificial semi-artificial forest land， and based on the principle that the state， collectives and individuals go together， efforts shall be made to coordinate and match the strategies and measures of the protection and application of forest lands for the development of primitive forests construction of artificial semi-artificial forests， and process of forest by-products. It is necessary to actively identify and promote high-quality tree species with high benefits and high yields， build artificial semi-planted forests according to local conditions， and promote and enhance forest output and forest disaster prevention. In the allocation of funds， efforts shall be needed to spend the money to the best in a planned and step-by-step manner， so that ecological benefits and economic benefits are closely combined. While strengthening investment in construction， it needs to reform investment methods， set up a reasonable investment structure， and formulate appropriate economic indicators. It is necessary to increase both material input and intellectual input， vigorously cultivate professional talents at all levels， improve the technical level of forest land management， and make full and rational use of funds. For example， in areas with severe biological disasters， efforts can be made to control the damage below the hazard level as soon as possible， and use quick-acting chemical measures together with long-term biological control to achieve long-term eradication purposes.

The protection of forest resources is the core element of ecological civilization construction. In recent years， China has invested a lot of money in implementing key ecological projects such as returning farmland to forests， closing hills for afforestation， forest planting and natural forest protection， resulting in remarkable achievements in the construction of ecological civilization. According to the Detailed Rules for the Implementation of the Forest Law of the Peoples Republic of China， Chinas national forest coverage rate is set at 30%， with mountainous areas generally reaching more than 70%， hilly areas more than 40%， and plain areas more than 10%. The government at or above the county level shall， in accordance with the above-mentioned standards， determine the goal of forest coverage within its administrative region. To accomplish the above goals， it needs： ① All departments shall put forward greening standards and goals for the industry in accordance with relevant national regulations; ② Coal mines and paper mills using wood as raw materials must have their own timber bases where conditions permit; ③ The locals with  forest farms， barren hills and wastelands， waste mines， and those in charge of railways， highways， and water conservancy projects must make good planning， implement responsibilities， and speed up the pace of greening; ④ For new and expansion projects， attention should be paid to greening the environment， and including environmental greening and beautification in planning and design; ⑤ The tree species， saplings and technical force required for greening should depend on self-reliance， and the forestry and gardening departments should cooperate vigorously; ⑧ Each unit should have leading cadres in charge of greening work.

Enhancing the energy status of forest areas

The development and utilization of forest biomass energy resources is one of the important ways to solve the bottleneck problem of raw materials for biomass energy development in China. With a long winter， China is facing serious energy crisis due to the lack of firewood. To actively develop energy， it should mobilize all forces to solve the energy shortage， improve the energy situation through various means， gradually eliminate the factors that destroy forests like cutting， digging and hugging due to lack of energy， and weaken the disaster-causing factors. Therefore， the following measures should be taken：

Carrying out rural energy planning

Rural energy planning is a basic work of energy planning and the basis for formulating energy planning and policies. It has certain significance for rural energy construction and national economic development. That is， energy resources are planned according to localities. It is necessary to zone and plan the natural conditions， residents living standards， traffic conditions and consumption structure， work out a structural model to solve the energy needs of rural living in multiple ways， and implement the policy of developing both industrial-specific energy and rural multi-purpose firewood forests to lead Chinas energy forests to commercial development.

Vigorously planting trees and developing firewood forests

An important way to solve the energy problem in rural areas is to vigorously plant trees and develop firewood forests. Firewood forests refer to forests whose main purpose is to produce fuels such as firewood， charcoal， the bioenergy represented by firewood forest is cleaner and cheaper than coal， oil and natural gas.r Rural firewood forests should be multi-purposed， which should combine the production of firewood production with other benefits， combine long-term interests with short-term interests.  Research should be actively carried out on firewood forests， so as to select excellent and fast-growing firewood species as soon as possible. The selected species must be applicable to a wide range， with strong germination ability， high biomass energy and great economic potential. The local firewood tree species should also be screened again， and a group of excellent tree species that can adapt to the ecological environment should be selected as soon as possible. In China， the area and volume of firewood forests account for about 3.4% of the forest area and 0.9% of the timber volume. Thus， building firewood forests is one of the important ways to solve the problem of rural energy in todays world.

Replacing coarse coal combustion with clean heating in forest areas

The replacement of coarse coal combustion in forest areas with clean heating should stick to the principle of multiple scientific choices available with multiple measures simultaneously applicable based on the idea of  being economical and practical （gas， electricity and coal can be selected according to the local practical conditions， and it should also complement with other clean energy）， so as to steadily promote the replacement of clean energy in a planned way. Under the conditions that residents can bear， the replacement should be progressed in a way that not only ensure a warm winter for the masses， but also promote haze control. In terms of utilization mode， efforts should be made to transform the current backward mode mainly based on direct combustion， adopt various methods  to complete the work of rural stove conversion， actively research and develop vaporization and liquefaction technology， and develop modern utilization mode.

Strengthening rural energy construction

It is an objective requirement of ecological environment protection to strengthen rural energy construction. Shaanxi is an economically underdeveloped province and a province with a fragile ecological environment. The resource distribution in the province is uneven and the natural conditions are poor. There are quite a few places in the vast rural areas that not only face the problems of food and clothing and insufficient income， but also suffer from energy shortages， especially the problem of fuel shortage. Thus， it is necessary to establish and improve the rural energy management system and accelerate the pace of forest energy construction.

Incorporating the production of forest energy into modern management

Forest production should be built up， so as to form a forest area energy system combined with production， processing and sales， and a forest energy industry with modern technology should also be established.

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