With the background of severe rocky desertification in the west of China and the ohjective of ecological environment construction and poverty elimination, the management information system of rocky desertification was...With the background of severe rocky desertification in the west of China and the ohjective of ecological environment construction and poverty elimination, the management information system of rocky desertification was designed according to the natural and humane characteristics in Nanchuan of Sichuan Province. The system was composed of data management module, information query module for rocky desertification, spatial analysis module and dynamic monitoring module.展开更多
Mycorrhizal mulberry is a plant, whose mulberry root and Arbuscular Myc-orrhizal fungi came into being a symbiotic relationship by a mean of natural or artifi-cial inoculation. Mycorrhizal mulberry coupling with main ...Mycorrhizal mulberry is a plant, whose mulberry root and Arbuscular Myc-orrhizal fungi came into being a symbiotic relationship by a mean of natural or artifi-cial inoculation. Mycorrhizal mulberry coupling with main ecological barriers, such as barren soil drought in rocky desertification area, wil be beneficial to recovering the karst degraded ecosystem by removing these stresses. So, mycorrhizal mulberry is considered a new effective way in ecological control of karst rocky desertification. The research summarized the structures and the characteristic eco-physiological functions of arbuscular mycorrhizal fungi (AMF), and preliminarily discussed its availability and research in karst rocky desertification restoration ,including investiga-tion of AMF diversity, the key affecting factor of AMF species diversity, the sym-biosis mechanism between AMF and mulberry, promoting the development of agri-cultural economy in Karst Rocky Desertification area by mycorrhizal mulberry. These elaborate efforts are to demonstrate mycorrhizal mulberry adapting to karst environ-ment from a new view, lay a theoretical basis for karst degraded-ecosystem restoration, and final y guarantee sustainable development of mycorrhizal mulberry in rocky desertification area.展开更多
Sensitivity evaluation of rocky desertification is to recognize the areas prone to be rock-deserted,so as to assess the sensitivity degree of rocky desertification to human activities.To perform the sensitivity evalua...Sensitivity evaluation of rocky desertification is to recognize the areas prone to be rock-deserted,so as to assess the sensitivity degree of rocky desertification to human activities.To perform the sensitivity evaluation of rocky desertification,we should be on the basis of the mechanism of rocky desertification formation for analyzing its regional distribution difference in the sensitivity and further for finding out the rocky desertification-susceptive areas and their possible degrees.Employing remote sensing and geological information system techniques,we regarded the 1∶ 50 000 topographic map and the TM image in 2000 of Guizhou Province,together with the hydrologic map,soil map,geologic map,rock formation map,administrative map and other geological information as data sources to generate the degree data of rocky desertification sensitivity of Guizhou Province in 1962 and 2000,based on which we determined the corresponding degree transfer matrix and adopted Markov model to simulate the dynamic change process of rocky desertification sensitivity and its future evolution trend.In various sensitivity types of rocky desertification in Guizhou Province,only the insensitive type showed a declined acreage,from the proportion of total land acreage of 61.35% in 1962 to 55.55% in 2000.Various sensitivity types inter-conversed,resultantly the acreage of mildly sensitive type increased most.The prediction results showed that the acreage of insensitive type of rocky desertification in Guizhou Province will assume a remarkable decline trend,of mildly sensitive type will present a remarkably increasing trend and of slightly sensitive type basically will maintain a stable level in the future tens of years.Acreages of both highly sensitive and extremely sensitive type of rocky desertification expanded to some extent,suggesting that the rocky desertification risk in Guizhou Province is in an aggravating process.展开更多
With intensifying of karst rock desertification in Southwest China, the techniques and modes about taming of karst rock desertification are increasingly rich. But some methods and technologies were hard to transplant....With intensifying of karst rock desertification in Southwest China, the techniques and modes about taming of karst rock desertification are increasingly rich. But some methods and technologies were hard to transplant. According to the concrete conditions of karst rock desertification in Chongqing, Lippia nodiflora(L.) Greene was introduced as a kind of pioneer plant. By way of the cultivation of introduced practice in Nanchuan District and Wushan County, the phenophase, growth rate and resistibility of Lippia nodiflora were tested. The results show that Lippia nodiflora was suitable for being promoted in karst rock desertification areas, for it’s rapid growth, drought-relief, low death rate and adaptability to calcium in soil.展开更多
With a subtropical climate,Guangxi Zhuang Autonomous Region has a typical karst landscape.Rocky desertification has become a serious environmental issue due to its high vulnerability caused by the joint effect of natu...With a subtropical climate,Guangxi Zhuang Autonomous Region has a typical karst landscape.Rocky desertification has become a serious environmental issue due to its high vulnerability caused by the joint effect of natural settings and human activities,because of which its eco-environment has been deteriorated in recent years,and farmland has been disappearing sharply at the same time.This,in turn,has exacerbated the poverty level in the rural areas of the region.In this study,we monitored the spatial distribution of rocky land desertification and its temporal evolution using Landsat TM/ETM images of 1985,1995,2000 and 2005.We also analyzed the driving forces of the desertification and its expansion.Through constructing regression models by using all the relevant variables and considering the lagged effects as well as fixed effects,we quantified the exact role of different factors causing rocky land desertification in the study area with some new findings.The new findings in this study are greatly helpful for preserving,restoring and reconstructing the degraded mountain environment in Guangxi and other karst areas in Southwest China,and also for alleviating poverty in the rural areas in the future.展开更多
Karst rocky desertification is one of the major ecological and environmental problems that threaten the sustainable development of southwestern China. It is caused by irrational and intensive land-use patterns in kars...Karst rocky desertification is one of the major ecological and environmental problems that threaten the sustainable development of southwestern China. It is caused by irrational and intensive land-use patterns in karst geo-ecological environment. Therefore, it is vital to identify how human forces work on this degraded environment. Based on the soil erosion information in 2000 and remote sensing images of Guanling County collected in 2000 and 2007, four grades of karst rocky desertification data in 14 villages of Guanling County were extracted. Impacts of population, affluence, and other human forces on karst rocky desertification were analyzed using STIRPAT model. The results show that:1) Factors of population and affluence had strong influence on karst rocky desertification. In the STIRPAT model analysis, the population and affluence coefficients were positive, indicating that the increase in population and affluence would lead to more serious desertification. 2) Factors of farmer correlated with karst rocky desertification negatively, especially the way of viewing the relationship between people and nature, and the level of knowledge about rocky desertification. Government behavior was not a significant factor in this analysis. 3) The findings provide evidence that STIRPAT model can be used to analyze the relationship between human driving forces and rocky desertification.展开更多
Karst rocky desertification is a geo-ecological problem in Southwest China. The rocky desertification risk zone delineation could be used as a guide for the regional and hierarchical rocky desertification management a...Karst rocky desertification is a geo-ecological problem in Southwest China. The rocky desertification risk zone delineation could be used as a guide for the regional and hierarchical rocky desertification management and prevention. We chose the middle and lower reaches of the Houzhai underground basin on the karst plateau in Puding County, Guizhou Province, China as the study area and selected land use type, elevation, slope, aspect, lithology and settlement buffer as the main driving factors of the rocky desertification. The potential risk of rocky desertification was quantifed with the factor-weights union method and statistical analysis method. Five grades of rocky desertification risk were delineated based on Geographic Information System. The extremely low, low, moderate, high and extremely high rocky desertification risk zones accounted for 5.01%, 44.17%, 33.92%, 15.59% and 1.30%, respectively. As a whole, the rocky desertification risk level was moderate because the area of low and moderate rocky desertification risk zones occupied 78.09% of the study area. However, more than half of the area (about 50.81%) was predicted to have moderate rocky desertification risk and above, indicating that the study area was subject to rocky desertification. Rocky desertification risk was higher in the southeast and lower in the northwest of the study area. Distinct differences in the distribution of rocky desertification risk zones corresponding to different factors have been found.展开更多
Barbula fallax Hedw., Erythrodontium julaceum(Schwaegr.) Par., and Bryum argenteum Hedw. are typical rock mosses growing on rocks in different terrestrial habitats. In this study, B. fallax and E. julaceum, which are ...Barbula fallax Hedw., Erythrodontium julaceum(Schwaegr.) Par., and Bryum argenteum Hedw. are typical rock mosses growing on rocks in different terrestrial habitats. In this study, B. fallax and E. julaceum, which are epilithic mosses growing in rock desertification in Guizhou, China, were used as ecophysiological mosses in a combination of field investigations and laboratory experiments. We also investigated the reference moss B. argenteum, which is a widely distributed moss in habitats with soil as substrate. Our research focused on the response of the antioxidant defense system of epilithic mosses to drought stress. Most antioxidant defense indicators increased initially, then declined at later stages of drought stress. In contrast, the carotenoid content increased constantly. In addition, there was an initial increase(albeit variable) in relative membrane permeability, with this parameter showing a parabolic trend in all of the epilithic mosses. Among the three species, E. julaceum demonstrated the strongest resistance followed by B. fallax and then by B. argenteum. The epilithic mosses displayed stronger resistance compared to the native mosses; the increase in O_2 content and other reactive oxygen species(ROS) at the early stage of drought stress induced the enzymatic and non-enzymatic scavenging systems tosequester ROS. Moreover, the radical scavenging ability and strong drought tolerance was maintained. The longterm growth of bryophyte under drought conditions in a karst environment can help eliminate the intense response of mosses to drought stress as they adapt.展开更多
Syenogranitic dykes in the north of Egypt's Eastern Desert are of geological and economic interest because of the presence of magmatic and supergene enrichment of radioactive mineralization. Zircon crystal morphol...Syenogranitic dykes in the north of Egypt's Eastern Desert are of geological and economic interest because of the presence of magmatic and supergene enrichment of radioactive mineralization. Zircon crystal morphology within the syenogranitic dykes allows precise definition of sub-alkaline series granites and crystallized at mean temperature of about 637 °C. The growth pattern of the zircons suggest magmatic and hydrothermal origins of radioactive mineralization. Hydrothermal processes are responsible for the formation of significant zircon overgrowth; high U-zircon margins might have occurred contemporaneously with the emplacement of syenogranitic dykes which show anomalous uranium(e U) and thorium(e Th) contents of up to 1386 and 7330 ppm, respectively.Zircon chemistry revealed a relative increase of Hf consistent with decreasing Zr content, suggesting the replacement of Zr by Hf during hydrothermal activity.Visible uranium mineralization is present and recognized by the presence of uranophane and autunite.展开更多
To find Jatropha curcas L. accessions with characteristics suitable for rootstock plants, 11 selected accessions were analyzed in response to heavy soil. Six-week-old of jatropha were grown in 11 L ofentisols (M1) a...To find Jatropha curcas L. accessions with characteristics suitable for rootstock plants, 11 selected accessions were analyzed in response to heavy soil. Six-week-old of jatropha were grown in 11 L ofentisols (M1) and grumusols (M2) soil for 10 weeks, while andosols soil richer in organic carbon were used as control media (M0). Growth of shoot and primary as well as secondary roots were observed during and at the end of the experiment. Macro and micro nutrient uptake was also analyzed at the end of experiment. Ml and M2 caused dramatically reduction of roots as well as shoot growth of all accessions. The reduction of growth component was in accordance to all nutrient uptakes except Ca and Mg. The data showed that type of soil was one of important factors influencing growth and development of J. curcas. There were 4 accessions i.e. Sumatra-l (S1), Sumatra-2 (S2), Java-3 (J3) and Java-2 (J2) which had better roots and shoot characteristics that were potential to be used as rootstock plants.展开更多
Mine rocky desertification is another type of rocky desertification which coexists with Karst rocky desertification, suggested firstly by professor SONG Jian-bo, Guizhou University. Mine rocky desertification is a pro...Mine rocky desertification is another type of rocky desertification which coexists with Karst rocky desertification, suggested firstly by professor SONG Jian-bo, Guizhou University. Mine rocky desertification is a process and result that the earth's surface is similar to desert landscapes after rock is exposed gradually, owing to mine wastes discharged at will which consist of waste residue, waste liquid and waste gas. On the basis of introducing Karst rocky desertification simply, we clarify the concept of Mine rocky desertification systemically, analyze its danger and compare the differences between Mine rocky desertification and Karst rocky desertification. Finally, we make preliminary discussion on the study significance of comprehensive treatment of Mine rocky desertification展开更多
Based on a systematic analysis about the design principles, systematic objectives, clients’ demands and functional modules of the regional karst desertification disaster information system, a systematic application p...Based on a systematic analysis about the design principles, systematic objectives, clients’ demands and functional modules of the regional karst desertification disaster information system, a systematic application plan was proposed in this paper that the mainstream technologies like COMGIS, etc. can be used for secondary development, and Du’an Yao Autonomous County of Guangxi was taken as an example to illustrate the application of geographical information system in development of karst desertification disaster information system, and to provide a feasible plan for realization of accessory decision information aiming for sustainable development of karst desertification area.展开更多
Karst areas in Southwest China, with Guizhou as the focal center, are confronted with ecological deterioration and large areas of rocky desertification. Human activities are defined as the driving force behind the soi...Karst areas in Southwest China, with Guizhou as the focal center, are confronted with ecological deterioration and large areas of rocky desertification. Human activities are defined as the driving force behind the soil erosion. Further, local farmers in the area suffer from poverty due to a lack of drinking water, food and a weak living environment. Over one-third of national poverty-stricken counties occur in this part of China. To balance ecological protection and economic development in the region and help local farmers out of poverty we propose integrated controls and discuss on ground water exploration and sustainable use, soil conservation and remediation, and vegetation restoration (especially economic plant species) in this paper.展开更多
There are many branches of the Miao people in China, one of which is the Mashan Miao, who have been living in karst mountainous areas in southwest Guizhou Province. The Mashan Miao have adopted various measures for th...There are many branches of the Miao people in China, one of which is the Mashan Miao, who have been living in karst mountainous areas in southwest Guizhou Province. The Mashan Miao have adopted various measures for the conservation and effective utilization of the local ecological system and have made great achievements in this area. From the 1950s, their social environment has changed a lot due to political and economic movements. The rocky desertification in the Mashan area has gradually expanded. After the 1990s, relief work was carried out to address the desertification problem, but it was not very effective. We have been doing fieldwork in this area for more than 20 years and from our fieldwork records, we have found that the local Miao people have traditional ecological knowledge and skills that are of irreplaceable valuable for finding a solution for rocky desertification. Using the Miao knowledge we think a feasible way to control this disaster can be found.展开更多
Rocky desertification is a serious threat to socioeconomic development and the ecological security of karst areas. The control of rocky desertification has therefore become a major concern of both the Chinese governme...Rocky desertification is a serious threat to socioeconomic development and the ecological security of karst areas. The control of rocky desertification has therefore become a major concern of both the Chinese government and local populations living in karst areas. In this paper, we used the national evaluation system for monitoring rocky desertification, and adjusted relevant indices. For example, we improved the system's base rock exposure index with Normalized Difference Rock index(NDRI), substituted a soil erosion index for soil depth, and from these obtained the categories and spatial distribution of rocky desertification. We also studied the main factors and functional mechanisms of rocky desertification with consideration given to natural geographic conditions such as soil, physiognomy, elevation, slope and river network density, and, also human interference factors such as population density, GDP, population distribution, and from these got spatial distribution characteristics and influencing factors of rocky desertification in Qiandongnan prefecture. Results indicate that the primary soil types of rocky desertification in the research areas include yellow, limestone and paddy soils. These rocky desertification areas are more likely to contain limestone soil than purple soil, and least likely to contain paddy soil. The distribution of moderate or severe rocky desertification in areas with moderate to steep slope is 40%, where sloping agricultural land comprises a large proportion of the total. Rocky desertification is widely distributed in regions with precipitation between 1000–1200 mm, and this precipitation is the main factor causing greater soil erosion in limestone soil base and sloping agricultural areas. Moreover, desertification is closely related to the distribution of residential areas, population density, poverty and sloping agricultural land展开更多
Karst areas in southwest China have experienced significant land cover and land use change(LUCC)due to utilization for human activity and a comprehensive rocky desertification control project(RDCP)since 2008.It is imp...Karst areas in southwest China have experienced significant land cover and land use change(LUCC)due to utilization for human activity and a comprehensive rocky desertification control project(RDCP)since 2008.It is important to quantify the effect of LUCC on ecosystem productivity in this region for assessing the overall benefit of this ecological restoration project.In this study,we used using MODIS land cover and NPP products to investigate the relative contribution of LUCC to the change in net primary productivity(NPP)during 2008–2013 in Huanjiang County,one of first one hundred pilot counties to implement RDCP.Our results show that NPP increased in 95.53%of the county,and the average growth of NPP in non-rocky desertification area was higher than in rocky desertification or potential rocky desertification areas.LUCC has an important contribution(25.23%)to the NPP increase in the county,especially in the LUCC area(70.97%),which increased the average NPP by 3.9%and 10.5%,respectively.Across the six RDCP regions in the county,the average increase in NPP for the vegetation restoration measure of governed karst area is significantly greater than in the ungoverned karst area,and the positive change in NPP increased with the increasing implementation area of the vegetation restoration measure.展开更多
Vegetation restoration is the primary task of ecological reconstruction and rocky desertification control in Karst areas. With vegetation net primary productivity and coverage as two key indicators, a vegetation ecolo...Vegetation restoration is the primary task of ecological reconstruction and rocky desertification control in Karst areas. With vegetation net primary productivity and coverage as two key indicators, a vegetation ecological quality evaluation model was built based on meteorological and remote sensing data. Spatiotemporal variation of vegetation ecological quality index and its response to climate change in rocky desertification areas in Southwest China during 2000-2020 were also analyzed by using the difference method and linear trend method. The results showed that:(1) Vegetation ecological quality in rocky desertification areas in Southwest China showed a fluctuating upward trend during 2000-2020. In 2020, the vegetation ecological quality index reached 69.7, which was 19.9% and 9.3% higher than the averaged values for 2000 and 2000-2019, respectively, ranking the fourth highest since 2000.(2) Vegetation ecological quality of the rocky desertification areas in Yunnan, Guangxi and Guizhou provinces have been improved by 89.2%, 99.2% and 98.5%, respectively, from 2000 to 2020, with their vegetation ecological quality index values increasing by 0.5-0.75 per year in southeast Yunnan, most areas in Guizhou and northwest Guangxi.(3) Precipitation was an important meteorological factor affecting the vegetation ecological quality in rocky desertification areas. The vegetation ecological quality index in the northwest and central Yunnan rocky desertification areas has been rising slowly, but with localized declines at a yearly rate of nearly 0.25 caused by climatic warming and drying.展开更多
基金the National Science and Technology Key Project (2006BAC01A16)Program of Chongqing Science Committee (2004-8258)~~
文摘With the background of severe rocky desertification in the west of China and the ohjective of ecological environment construction and poverty elimination, the management information system of rocky desertification was designed according to the natural and humane characteristics in Nanchuan of Sichuan Province. The system was composed of data management module, information query module for rocky desertification, spatial analysis module and dynamic monitoring module.
基金Supported by Special Foundation for Innovation Capacity Construction of Guizhou Provincial Department of Science and Technology([2012]4003)~~
文摘Mycorrhizal mulberry is a plant, whose mulberry root and Arbuscular Myc-orrhizal fungi came into being a symbiotic relationship by a mean of natural or artifi-cial inoculation. Mycorrhizal mulberry coupling with main ecological barriers, such as barren soil drought in rocky desertification area, wil be beneficial to recovering the karst degraded ecosystem by removing these stresses. So, mycorrhizal mulberry is considered a new effective way in ecological control of karst rocky desertification. The research summarized the structures and the characteristic eco-physiological functions of arbuscular mycorrhizal fungi (AMF), and preliminarily discussed its availability and research in karst rocky desertification restoration ,including investiga-tion of AMF diversity, the key affecting factor of AMF species diversity, the sym-biosis mechanism between AMF and mulberry, promoting the development of agri-cultural economy in Karst Rocky Desertification area by mycorrhizal mulberry. These elaborate efforts are to demonstrate mycorrhizal mulberry adapting to karst environ-ment from a new view, lay a theoretical basis for karst degraded-ecosystem restoration, and final y guarantee sustainable development of mycorrhizal mulberry in rocky desertification area.
基金Supported by Programs for Science and Technology Development of Guizhou Province(20073017,20083022)National Basic Research Program of China(973Program,2006CB403200)~~
文摘Sensitivity evaluation of rocky desertification is to recognize the areas prone to be rock-deserted,so as to assess the sensitivity degree of rocky desertification to human activities.To perform the sensitivity evaluation of rocky desertification,we should be on the basis of the mechanism of rocky desertification formation for analyzing its regional distribution difference in the sensitivity and further for finding out the rocky desertification-susceptive areas and their possible degrees.Employing remote sensing and geological information system techniques,we regarded the 1∶ 50 000 topographic map and the TM image in 2000 of Guizhou Province,together with the hydrologic map,soil map,geologic map,rock formation map,administrative map and other geological information as data sources to generate the degree data of rocky desertification sensitivity of Guizhou Province in 1962 and 2000,based on which we determined the corresponding degree transfer matrix and adopted Markov model to simulate the dynamic change process of rocky desertification sensitivity and its future evolution trend.In various sensitivity types of rocky desertification in Guizhou Province,only the insensitive type showed a declined acreage,from the proportion of total land acreage of 61.35% in 1962 to 55.55% in 2000.Various sensitivity types inter-conversed,resultantly the acreage of mildly sensitive type increased most.The prediction results showed that the acreage of insensitive type of rocky desertification in Guizhou Province will assume a remarkable decline trend,of mildly sensitive type will present a remarkably increasing trend and of slightly sensitive type basically will maintain a stable level in the future tens of years.Acreages of both highly sensitive and extremely sensitive type of rocky desertification expanded to some extent,suggesting that the rocky desertification risk in Guizhou Province is in an aggravating process.
基金Supported by National Key Technology R&D Program of the the Eleventh Five-Year Plan (2006BAC01A16)~~
文摘With intensifying of karst rock desertification in Southwest China, the techniques and modes about taming of karst rock desertification are increasingly rich. But some methods and technologies were hard to transplant. According to the concrete conditions of karst rock desertification in Chongqing, Lippia nodiflora(L.) Greene was introduced as a kind of pioneer plant. By way of the cultivation of introduced practice in Nanchuan District and Wushan County, the phenophase, growth rate and resistibility of Lippia nodiflora were tested. The results show that Lippia nodiflora was suitable for being promoted in karst rock desertification areas, for it’s rapid growth, drought-relief, low death rate and adaptability to calcium in soil.
基金supported by the Project of the National Natural Science Foundation of China (Grant number 40635029 40871257)the Knowledge Innovation Program of Chinese Academy of Sciences (grant number KSCX-YW-09)
文摘With a subtropical climate,Guangxi Zhuang Autonomous Region has a typical karst landscape.Rocky desertification has become a serious environmental issue due to its high vulnerability caused by the joint effect of natural settings and human activities,because of which its eco-environment has been deteriorated in recent years,and farmland has been disappearing sharply at the same time.This,in turn,has exacerbated the poverty level in the rural areas of the region.In this study,we monitored the spatial distribution of rocky land desertification and its temporal evolution using Landsat TM/ETM images of 1985,1995,2000 and 2005.We also analyzed the driving forces of the desertification and its expansion.Through constructing regression models by using all the relevant variables and considering the lagged effects as well as fixed effects,we quantified the exact role of different factors causing rocky land desertification in the study area with some new findings.The new findings in this study are greatly helpful for preserving,restoring and reconstructing the degraded mountain environment in Guangxi and other karst areas in Southwest China,and also for alleviating poverty in the rural areas in the future.
基金Under the auspices of National Natural Science Foundation of China(No.40801039,40801066,41001183)
文摘Karst rocky desertification is one of the major ecological and environmental problems that threaten the sustainable development of southwestern China. It is caused by irrational and intensive land-use patterns in karst geo-ecological environment. Therefore, it is vital to identify how human forces work on this degraded environment. Based on the soil erosion information in 2000 and remote sensing images of Guanling County collected in 2000 and 2007, four grades of karst rocky desertification data in 14 villages of Guanling County were extracted. Impacts of population, affluence, and other human forces on karst rocky desertification were analyzed using STIRPAT model. The results show that:1) Factors of population and affluence had strong influence on karst rocky desertification. In the STIRPAT model analysis, the population and affluence coefficients were positive, indicating that the increase in population and affluence would lead to more serious desertification. 2) Factors of farmer correlated with karst rocky desertification negatively, especially the way of viewing the relationship between people and nature, and the level of knowledge about rocky desertification. Government behavior was not a significant factor in this analysis. 3) The findings provide evidence that STIRPAT model can be used to analyze the relationship between human driving forces and rocky desertification.
基金Under the auspices of Major Basic Reseach Development Program of China (973 Program) (No. 2006CB403201)
文摘Karst rocky desertification is a geo-ecological problem in Southwest China. The rocky desertification risk zone delineation could be used as a guide for the regional and hierarchical rocky desertification management and prevention. We chose the middle and lower reaches of the Houzhai underground basin on the karst plateau in Puding County, Guizhou Province, China as the study area and selected land use type, elevation, slope, aspect, lithology and settlement buffer as the main driving factors of the rocky desertification. The potential risk of rocky desertification was quantifed with the factor-weights union method and statistical analysis method. Five grades of rocky desertification risk were delineated based on Geographic Information System. The extremely low, low, moderate, high and extremely high rocky desertification risk zones accounted for 5.01%, 44.17%, 33.92%, 15.59% and 1.30%, respectively. As a whole, the rocky desertification risk level was moderate because the area of low and moderate rocky desertification risk zones occupied 78.09% of the study area. However, more than half of the area (about 50.81%) was predicted to have moderate rocky desertification risk and above, indicating that the study area was subject to rocky desertification. Rocky desertification risk was higher in the southeast and lower in the northwest of the study area. Distinct differences in the distribution of rocky desertification risk zones corresponding to different factors have been found.
基金supported by funds from the National Natural Science Foundation(Grant No.41463006)
文摘Barbula fallax Hedw., Erythrodontium julaceum(Schwaegr.) Par., and Bryum argenteum Hedw. are typical rock mosses growing on rocks in different terrestrial habitats. In this study, B. fallax and E. julaceum, which are epilithic mosses growing in rock desertification in Guizhou, China, were used as ecophysiological mosses in a combination of field investigations and laboratory experiments. We also investigated the reference moss B. argenteum, which is a widely distributed moss in habitats with soil as substrate. Our research focused on the response of the antioxidant defense system of epilithic mosses to drought stress. Most antioxidant defense indicators increased initially, then declined at later stages of drought stress. In contrast, the carotenoid content increased constantly. In addition, there was an initial increase(albeit variable) in relative membrane permeability, with this parameter showing a parabolic trend in all of the epilithic mosses. Among the three species, E. julaceum demonstrated the strongest resistance followed by B. fallax and then by B. argenteum. The epilithic mosses displayed stronger resistance compared to the native mosses; the increase in O_2 content and other reactive oxygen species(ROS) at the early stage of drought stress induced the enzymatic and non-enzymatic scavenging systems tosequester ROS. Moreover, the radical scavenging ability and strong drought tolerance was maintained. The longterm growth of bryophyte under drought conditions in a karst environment can help eliminate the intense response of mosses to drought stress as they adapt.
文摘Syenogranitic dykes in the north of Egypt's Eastern Desert are of geological and economic interest because of the presence of magmatic and supergene enrichment of radioactive mineralization. Zircon crystal morphology within the syenogranitic dykes allows precise definition of sub-alkaline series granites and crystallized at mean temperature of about 637 °C. The growth pattern of the zircons suggest magmatic and hydrothermal origins of radioactive mineralization. Hydrothermal processes are responsible for the formation of significant zircon overgrowth; high U-zircon margins might have occurred contemporaneously with the emplacement of syenogranitic dykes which show anomalous uranium(e U) and thorium(e Th) contents of up to 1386 and 7330 ppm, respectively.Zircon chemistry revealed a relative increase of Hf consistent with decreasing Zr content, suggesting the replacement of Zr by Hf during hydrothermal activity.Visible uranium mineralization is present and recognized by the presence of uranophane and autunite.
文摘To find Jatropha curcas L. accessions with characteristics suitable for rootstock plants, 11 selected accessions were analyzed in response to heavy soil. Six-week-old of jatropha were grown in 11 L ofentisols (M1) and grumusols (M2) soil for 10 weeks, while andosols soil richer in organic carbon were used as control media (M0). Growth of shoot and primary as well as secondary roots were observed during and at the end of the experiment. Macro and micro nutrient uptake was also analyzed at the end of experiment. Ml and M2 caused dramatically reduction of roots as well as shoot growth of all accessions. The reduction of growth component was in accordance to all nutrient uptakes except Ca and Mg. The data showed that type of soil was one of important factors influencing growth and development of J. curcas. There were 4 accessions i.e. Sumatra-l (S1), Sumatra-2 (S2), Java-3 (J3) and Java-2 (J2) which had better roots and shoot characteristics that were potential to be used as rootstock plants.
文摘Mine rocky desertification is another type of rocky desertification which coexists with Karst rocky desertification, suggested firstly by professor SONG Jian-bo, Guizhou University. Mine rocky desertification is a process and result that the earth's surface is similar to desert landscapes after rock is exposed gradually, owing to mine wastes discharged at will which consist of waste residue, waste liquid and waste gas. On the basis of introducing Karst rocky desertification simply, we clarify the concept of Mine rocky desertification systemically, analyze its danger and compare the differences between Mine rocky desertification and Karst rocky desertification. Finally, we make preliminary discussion on the study significance of comprehensive treatment of Mine rocky desertification
基金China National Natural Science Foundation(Grant No.40361002)Guangxi Natural Science Foundation(Grant No.Gui Ke Zi 0342001-2)Guangxi Education Bureau Foundation(Grant No.Gui Jiao Ke Yan[2003.]22-3).
文摘Based on a systematic analysis about the design principles, systematic objectives, clients’ demands and functional modules of the regional karst desertification disaster information system, a systematic application plan was proposed in this paper that the mainstream technologies like COMGIS, etc. can be used for secondary development, and Du’an Yao Autonomous County of Guangxi was taken as an example to illustrate the application of geographical information system in development of karst desertification disaster information system, and to provide a feasible plan for realization of accessory decision information aiming for sustainable development of karst desertification area.
基金the Project of the China Geological Survey(No.12120113005300)the Ministry of Land and Resources(No.201211086-05)
文摘Karst areas in Southwest China, with Guizhou as the focal center, are confronted with ecological deterioration and large areas of rocky desertification. Human activities are defined as the driving force behind the soil erosion. Further, local farmers in the area suffer from poverty due to a lack of drinking water, food and a weak living environment. Over one-third of national poverty-stricken counties occur in this part of China. To balance ecological protection and economic development in the region and help local farmers out of poverty we propose integrated controls and discuss on ground water exploration and sustainable use, soil conservation and remediation, and vegetation restoration (especially economic plant species) in this paper.
基金Ministry of Education for New Century Excellent Talents Program (NCET-10-0146) National Social Science Foundation of China (08AJY025)
文摘There are many branches of the Miao people in China, one of which is the Mashan Miao, who have been living in karst mountainous areas in southwest Guizhou Province. The Mashan Miao have adopted various measures for the conservation and effective utilization of the local ecological system and have made great achievements in this area. From the 1950s, their social environment has changed a lot due to political and economic movements. The rocky desertification in the Mashan area has gradually expanded. After the 1990s, relief work was carried out to address the desertification problem, but it was not very effective. We have been doing fieldwork in this area for more than 20 years and from our fieldwork records, we have found that the local Miao people have traditional ecological knowledge and skills that are of irreplaceable valuable for finding a solution for rocky desertification. Using the Miao knowledge we think a feasible way to control this disaster can be found.
基金National Key Research and Development Program of China(2016YFC0503700)
文摘Rocky desertification is a serious threat to socioeconomic development and the ecological security of karst areas. The control of rocky desertification has therefore become a major concern of both the Chinese government and local populations living in karst areas. In this paper, we used the national evaluation system for monitoring rocky desertification, and adjusted relevant indices. For example, we improved the system's base rock exposure index with Normalized Difference Rock index(NDRI), substituted a soil erosion index for soil depth, and from these obtained the categories and spatial distribution of rocky desertification. We also studied the main factors and functional mechanisms of rocky desertification with consideration given to natural geographic conditions such as soil, physiognomy, elevation, slope and river network density, and, also human interference factors such as population density, GDP, population distribution, and from these got spatial distribution characteristics and influencing factors of rocky desertification in Qiandongnan prefecture. Results indicate that the primary soil types of rocky desertification in the research areas include yellow, limestone and paddy soils. These rocky desertification areas are more likely to contain limestone soil than purple soil, and least likely to contain paddy soil. The distribution of moderate or severe rocky desertification in areas with moderate to steep slope is 40%, where sloping agricultural land comprises a large proportion of the total. Rocky desertification is widely distributed in regions with precipitation between 1000–1200 mm, and this precipitation is the main factor causing greater soil erosion in limestone soil base and sloping agricultural areas. Moreover, desertification is closely related to the distribution of residential areas, population density, poverty and sloping agricultural land
基金The National Key Research&Development Program of China(2016YFC0500204)The National Natural Science Foundation of China(41571130043,31420103917,31971512)。
文摘Karst areas in southwest China have experienced significant land cover and land use change(LUCC)due to utilization for human activity and a comprehensive rocky desertification control project(RDCP)since 2008.It is important to quantify the effect of LUCC on ecosystem productivity in this region for assessing the overall benefit of this ecological restoration project.In this study,we used using MODIS land cover and NPP products to investigate the relative contribution of LUCC to the change in net primary productivity(NPP)during 2008–2013 in Huanjiang County,one of first one hundred pilot counties to implement RDCP.Our results show that NPP increased in 95.53%of the county,and the average growth of NPP in non-rocky desertification area was higher than in rocky desertification or potential rocky desertification areas.LUCC has an important contribution(25.23%)to the NPP increase in the county,especially in the LUCC area(70.97%),which increased the average NPP by 3.9%and 10.5%,respectively.Across the six RDCP regions in the county,the average increase in NPP for the vegetation restoration measure of governed karst area is significantly greater than in the ungoverned karst area,and the positive change in NPP increased with the increasing implementation area of the vegetation restoration measure.
基金The National Natural Science Foundation of China (31700421)。
文摘Vegetation restoration is the primary task of ecological reconstruction and rocky desertification control in Karst areas. With vegetation net primary productivity and coverage as two key indicators, a vegetation ecological quality evaluation model was built based on meteorological and remote sensing data. Spatiotemporal variation of vegetation ecological quality index and its response to climate change in rocky desertification areas in Southwest China during 2000-2020 were also analyzed by using the difference method and linear trend method. The results showed that:(1) Vegetation ecological quality in rocky desertification areas in Southwest China showed a fluctuating upward trend during 2000-2020. In 2020, the vegetation ecological quality index reached 69.7, which was 19.9% and 9.3% higher than the averaged values for 2000 and 2000-2019, respectively, ranking the fourth highest since 2000.(2) Vegetation ecological quality of the rocky desertification areas in Yunnan, Guangxi and Guizhou provinces have been improved by 89.2%, 99.2% and 98.5%, respectively, from 2000 to 2020, with their vegetation ecological quality index values increasing by 0.5-0.75 per year in southeast Yunnan, most areas in Guizhou and northwest Guangxi.(3) Precipitation was an important meteorological factor affecting the vegetation ecological quality in rocky desertification areas. The vegetation ecological quality index in the northwest and central Yunnan rocky desertification areas has been rising slowly, but with localized declines at a yearly rate of nearly 0.25 caused by climatic warming and drying.