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Stony desert areas in China had shrunk to 12 million hectares by the end of 2011, representing a 7.4-percent reduction from the 2005 figure, according to the second round of stony desertification monitoring released by the State Forestry Administration (SFA) on June 14.
It also revealed that by the end of 2010, a total of 3.03 million hectares of land had been reclaimed from stony deserts in 451 counties around the country.
“Stony deserts have been shrinking at an annual rate of 1.27 percent over the past few years,” Zhang Yongli, Deputy Director of the SFA, said at a recent press conference.
The latest round of monitoring was carried out from early 2011 to mid-May 2012, covering 463 counties in eight provincial regions heavily plagued by incursions of stony deserts, including Hubei, Hunan, Guangdong, Sichuan, Yunnan and Guizhou provinces, as well as Chongqing Municipality and Guangxi Zhuang Autonomous Region. More than 4,000 technicians were involved in the monitoring activities and an information system consisting of about 40,000 GPS-based monitoring points was set up.
“The results show that the expansion of stony desertification has initially been brought under control, and the ecological environment in karst regions has greatly improved,” Zhang said.
Cancer of the Earth
Stony desertification refers to the processes that transform a karst area that was covered by vegetation and soil into a stony landscape almost devoid of soil and vegetation. Dubbed a “cancer of the Earth,” it is a serious ecological problem in the subtropical karst regions in south and southwest China.
According to SFA statistics, the country has about 45 million hectares of karst landscape, which has been formed through the dissolution of bedrock. Of its 12 million hectares of existing stony desert areas, nearly 65 percent are in Guizhou, Yunnan, and Guangxi.
“Stony desertification is still a major threat to China’s karst terrain areas, since it leads to water shortages, severe soil erosion and frequent natural disasters,” said Xiong Kangning, a professor at the South China Karst Research Institute of Guizhou Normal University.
Guizhou is the region most severely affected by stony desertification. According to official statistics, of its total 17 million hectares of territory, 62 percent is karst landforms and 20 percent can be classified as rocky desert terrain.
In Guangxi, of the total 8.3 million hectares of karst landscapes, 2.4 million hectares are stony deserts, according to statistics from the regional forestry department.
The causes of stony desertification are various. The fragility of karst ecology in tropical and subtropical regions is the prime cause. The karst ecosystem is often characterized by droughts, floods, soil erosion, surface collapse, limited biodiversity and low primary productivity.
“The low soil forming capability of soluble rocks and their relative shortage in nutritive elements result in thin soils with low fertility, which readily succumb to stony desertification,” said Yuan Daoxian, a professor at the Institute of Karst Geology of Chinese Academy of Geological Sciences.
But human activities play a much bigger role in triggering stony desertification.
According to studies by the International Research Center on Karst under the UN Educational, Scientific and Cultural Organization, the population density in China’s karst regions is 208 persons per square km, 1.5 times of the nationwide average. But internationally accepted standards put it at no more than 100 persons per square km.
Population pressure has made it difficult to restore the ecological environment in areas threatened by stony desertification. To meet demand for food in those areas , people are obliged to grow maize on steep slopes. Soil in fissures between rocks has been tilled and bare soil after harvests results in severe erosion, stripping the slopes of soil in a few years’ time and reducing the area to wasteland.
Other human activities that aggravate stony desertification include fuel gathering, bush fires and air pollution.
“Many karst regions in China are short on energy resources. To obtain fuel, local residents clear the bush and grass on rocky slopes year after year and so make vegetation regeneration very difficult,” Yuan said.
At the same time, from many years of practice, farmers consider burnt grass ash to be a good fertilizer for crops, so they set fire to vegetation on slopes in late autumn and let the ash be washed down onto the farmland.
“However, such fires often get out of control, not only burning shrubs and grasses, but also killing mosses and algae on rock surfaces under the high temperatures generated,” Yuan said. Algae and mosses are pioneer plants for karst forest, so loss of them will make the recovery of vegetation even more difficult.
Besides, in some urbanized or industrial areas, air pollution and acid rain have a similar effect in killing pioneer species. In extreme cases, carbonate rock surfaces over broad areas are bleached white following the death of algae and lichen. “Studies show that such terribly degraded landscapes will not recover even in 20 years after the responsible damaging factors are removed,” Yuan said.
Direct results of stony desertification are water shortage, soil erosion and persistent
poverty since few crops can survive in such thin and arid soil. According to SFA statistics, of the total 592 national-level poverty-stricken counties, 227 are located in stony desert areas, with more than 50 million people living below poverty line.
In Guangxi, more than 90 percent of its poverty-stricken people are living in stony desert areas, according to the regional forestry department.
“Since stony desertification has dragged so many people into poverty, the work to control stony desertification should be integrated with efforts to improve local people’s livelihoods,” said Wang Guoliang, Deputy Director of the State Council Leading Group Office of Poverty Alleviation and Development.
Curing the illness
In 2008, the State Council, China’s cabinet, approved a plan to control stony desertification in karst regions in the country’s south and southwest. The plan called for greater investment in environmental improvement in the karst regions and special allocations to deal with desertification in eight priority provincial-level regions. One hundred counties in Guizhou, Yunnan and Guangxi were included in the plan.
The campaign to control stony desertification will be extended to 200 counties throughout the country by the end of 2015. Its goal is to turn another 4 million hectares of stony deserts into forests, said Du Ying, Vice Minister of the National Development and Reform Commission.
After years of fighting stony desertification, land conditions have greatly improved.
Reforestation and vegetation protection, the adjustment of rural energy structure and the application of modern agricultural technologies contribute a lot to ecological restoration in stony desert areas.
Local governments also encouraged farmers to grow cash crops on stony lands to improve vegetation and increase earnings. A new breed of goat, meanwhile, was also imported from Australia to stony desertificationaffected provinces. They feed on grass but leave the roots untouched.
“Intensive agriculture has been promoted in those areas to improve farming yields. The application of modern agricultural technologies are significant to the ecological restoration in those affected regions,” said Liu Tuo, Director of the Desertification Control Center under the SFA.
In Guizhou, 169 villages have benefited from a land revitalization project. About 40,000 hectares of grassland has emerged from bare rocky lands and now support 420,000 goats, which has helped to increase the per-capita income in these areas from 630 yuan ($98.98) in 2001 to 5,900 yuan ($926.94) last year, according to official statistics.
However, Zhang also warned that the country still faces severe challenges in fighting stony desertification, as activities including overgrazing and destroying forest for land reclamation still exist in some poor rural regions.
“Frequent natural disasters such as droughts and freezing weather have also posed difficulties in combating stony desertification,” Zhang said.
For instance, with successive years of drought, stony desert areas now spread at an annual rate of 6.8 percent in Qujing City, Yunnan Province.
Stony desert areas now threaten the headwater areas of the country’s major waterways, including the Pearl River, major tributaries of the Yangtze River, as well as water sources of the South-to-North Water Diversion Project and the Three Gorges reservoir, according to the SFA.
“The stony desert areas with water loss and soil erosion cause sand deposits in the lower reaches of the rivers, which pose great threats to the local environment, as well as to lives and assets along the rivers,” he said.
Li Maosong, a researcher on disaster reduction at the Chinese Academy of Agricultural Sciences, suggests governments at all levels continue to increase investment in local environmental improvement and give more subsidies to farmers to encourage them to abandon destructive farming practices that may aggravate stony desertification.
“A long-term mechanism should be established to supervise the recovery of the vegetation, in a bid to stop the degradation backlash in handling stony deserts,” said Zhong Shiquan, Deputy Director of Guangxi Meteorological and Disaster Research Institute.
It also revealed that by the end of 2010, a total of 3.03 million hectares of land had been reclaimed from stony deserts in 451 counties around the country.
“Stony deserts have been shrinking at an annual rate of 1.27 percent over the past few years,” Zhang Yongli, Deputy Director of the SFA, said at a recent press conference.
The latest round of monitoring was carried out from early 2011 to mid-May 2012, covering 463 counties in eight provincial regions heavily plagued by incursions of stony deserts, including Hubei, Hunan, Guangdong, Sichuan, Yunnan and Guizhou provinces, as well as Chongqing Municipality and Guangxi Zhuang Autonomous Region. More than 4,000 technicians were involved in the monitoring activities and an information system consisting of about 40,000 GPS-based monitoring points was set up.
“The results show that the expansion of stony desertification has initially been brought under control, and the ecological environment in karst regions has greatly improved,” Zhang said.
Cancer of the Earth
Stony desertification refers to the processes that transform a karst area that was covered by vegetation and soil into a stony landscape almost devoid of soil and vegetation. Dubbed a “cancer of the Earth,” it is a serious ecological problem in the subtropical karst regions in south and southwest China.
According to SFA statistics, the country has about 45 million hectares of karst landscape, which has been formed through the dissolution of bedrock. Of its 12 million hectares of existing stony desert areas, nearly 65 percent are in Guizhou, Yunnan, and Guangxi.
“Stony desertification is still a major threat to China’s karst terrain areas, since it leads to water shortages, severe soil erosion and frequent natural disasters,” said Xiong Kangning, a professor at the South China Karst Research Institute of Guizhou Normal University.
Guizhou is the region most severely affected by stony desertification. According to official statistics, of its total 17 million hectares of territory, 62 percent is karst landforms and 20 percent can be classified as rocky desert terrain.
In Guangxi, of the total 8.3 million hectares of karst landscapes, 2.4 million hectares are stony deserts, according to statistics from the regional forestry department.
The causes of stony desertification are various. The fragility of karst ecology in tropical and subtropical regions is the prime cause. The karst ecosystem is often characterized by droughts, floods, soil erosion, surface collapse, limited biodiversity and low primary productivity.
“The low soil forming capability of soluble rocks and their relative shortage in nutritive elements result in thin soils with low fertility, which readily succumb to stony desertification,” said Yuan Daoxian, a professor at the Institute of Karst Geology of Chinese Academy of Geological Sciences.
But human activities play a much bigger role in triggering stony desertification.
According to studies by the International Research Center on Karst under the UN Educational, Scientific and Cultural Organization, the population density in China’s karst regions is 208 persons per square km, 1.5 times of the nationwide average. But internationally accepted standards put it at no more than 100 persons per square km.
Population pressure has made it difficult to restore the ecological environment in areas threatened by stony desertification. To meet demand for food in those areas , people are obliged to grow maize on steep slopes. Soil in fissures between rocks has been tilled and bare soil after harvests results in severe erosion, stripping the slopes of soil in a few years’ time and reducing the area to wasteland.
Other human activities that aggravate stony desertification include fuel gathering, bush fires and air pollution.
“Many karst regions in China are short on energy resources. To obtain fuel, local residents clear the bush and grass on rocky slopes year after year and so make vegetation regeneration very difficult,” Yuan said.
At the same time, from many years of practice, farmers consider burnt grass ash to be a good fertilizer for crops, so they set fire to vegetation on slopes in late autumn and let the ash be washed down onto the farmland.
“However, such fires often get out of control, not only burning shrubs and grasses, but also killing mosses and algae on rock surfaces under the high temperatures generated,” Yuan said. Algae and mosses are pioneer plants for karst forest, so loss of them will make the recovery of vegetation even more difficult.
Besides, in some urbanized or industrial areas, air pollution and acid rain have a similar effect in killing pioneer species. In extreme cases, carbonate rock surfaces over broad areas are bleached white following the death of algae and lichen. “Studies show that such terribly degraded landscapes will not recover even in 20 years after the responsible damaging factors are removed,” Yuan said.
Direct results of stony desertification are water shortage, soil erosion and persistent
poverty since few crops can survive in such thin and arid soil. According to SFA statistics, of the total 592 national-level poverty-stricken counties, 227 are located in stony desert areas, with more than 50 million people living below poverty line.
In Guangxi, more than 90 percent of its poverty-stricken people are living in stony desert areas, according to the regional forestry department.
“Since stony desertification has dragged so many people into poverty, the work to control stony desertification should be integrated with efforts to improve local people’s livelihoods,” said Wang Guoliang, Deputy Director of the State Council Leading Group Office of Poverty Alleviation and Development.
Curing the illness
In 2008, the State Council, China’s cabinet, approved a plan to control stony desertification in karst regions in the country’s south and southwest. The plan called for greater investment in environmental improvement in the karst regions and special allocations to deal with desertification in eight priority provincial-level regions. One hundred counties in Guizhou, Yunnan and Guangxi were included in the plan.
The campaign to control stony desertification will be extended to 200 counties throughout the country by the end of 2015. Its goal is to turn another 4 million hectares of stony deserts into forests, said Du Ying, Vice Minister of the National Development and Reform Commission.
After years of fighting stony desertification, land conditions have greatly improved.
Reforestation and vegetation protection, the adjustment of rural energy structure and the application of modern agricultural technologies contribute a lot to ecological restoration in stony desert areas.
Local governments also encouraged farmers to grow cash crops on stony lands to improve vegetation and increase earnings. A new breed of goat, meanwhile, was also imported from Australia to stony desertificationaffected provinces. They feed on grass but leave the roots untouched.
“Intensive agriculture has been promoted in those areas to improve farming yields. The application of modern agricultural technologies are significant to the ecological restoration in those affected regions,” said Liu Tuo, Director of the Desertification Control Center under the SFA.
In Guizhou, 169 villages have benefited from a land revitalization project. About 40,000 hectares of grassland has emerged from bare rocky lands and now support 420,000 goats, which has helped to increase the per-capita income in these areas from 630 yuan ($98.98) in 2001 to 5,900 yuan ($926.94) last year, according to official statistics.
However, Zhang also warned that the country still faces severe challenges in fighting stony desertification, as activities including overgrazing and destroying forest for land reclamation still exist in some poor rural regions.
“Frequent natural disasters such as droughts and freezing weather have also posed difficulties in combating stony desertification,” Zhang said.
For instance, with successive years of drought, stony desert areas now spread at an annual rate of 6.8 percent in Qujing City, Yunnan Province.
Stony desert areas now threaten the headwater areas of the country’s major waterways, including the Pearl River, major tributaries of the Yangtze River, as well as water sources of the South-to-North Water Diversion Project and the Three Gorges reservoir, according to the SFA.
“The stony desert areas with water loss and soil erosion cause sand deposits in the lower reaches of the rivers, which pose great threats to the local environment, as well as to lives and assets along the rivers,” he said.
Li Maosong, a researcher on disaster reduction at the Chinese Academy of Agricultural Sciences, suggests governments at all levels continue to increase investment in local environmental improvement and give more subsidies to farmers to encourage them to abandon destructive farming practices that may aggravate stony desertification.
“A long-term mechanism should be established to supervise the recovery of the vegetation, in a bid to stop the degradation backlash in handling stony deserts,” said Zhong Shiquan, Deputy Director of Guangxi Meteorological and Disaster Research Institute.