Desertification is a global crucial ecological and environmental issue,and China is among the countries most seriously affected by desertification.In recent decades,numerous independent studies on desertification dyna...Desertification is a global crucial ecological and environmental issue,and China is among the countries most seriously affected by desertification.In recent decades,numerous independent studies on desertification dynamics have been carried out using remote sensing technology,but there has been a lack of systematic research on desertification trends in China.This study employed the meta-analysis to integrate the findings of 140 published research cases and examined the dynamics of desertification in the eight major deserts,four major sandy lands,and their surrounding areas in China from 1970 to 2019,with a comparative analysis of differences between the eastern(including the Mu Us Sandy Land,the Otindag Sandy Land,the Hulunbuir Sandy Land,the Horqin Sandy Land,and the Hobq Desert)and western(including the Taklimakan Desert,the Gurbantunggut Desert,the Kumtagh Desert,the Ulan Buh Desert,the Qaidam Basin Desert,the Badain Jaran Desert,and the Tengger Desert)regions.The results revealed that from 1970 to 2019,desertification first expanded and then reversed in the whole region.Specifically,desertification expanded from 1980 to 1999 and reversed after 2000.The desertification trend exhibited distinct spatio-temporal variations between the eastern and western regions.From 1970 to 2019,the western region experienced relatively minor changes in desertified land area compared to the eastern region.In the context of global climate change,beneficial climatic conditions and ecological construction projects played a crucial role in reversing desertification.These findings provide valuable insights for understanding the development patterns of desertification in the most representative deserts and sandy lands in China and formulating effective desertification control strategies.展开更多
Due to irrational human activities and extreme climate,the Qinghai-Xizang Plateau,China,faces a serious threat of desertification.Desertification has a detrimental effect on the ecological environment and socioeconomi...Due to irrational human activities and extreme climate,the Qinghai-Xizang Plateau,China,faces a serious threat of desertification.Desertification has a detrimental effect on the ecological environment and socioeconomic development.In this study,the desertification sensitivity index(DSI)model was established by integrating the spatial distance model and environmentally sensitive area index evaluation method,and then the model was used to quantitatively analyze the spatial and temporal characteristics of desertification sensitivity of the Qinghai-Xizang Plateau from 1990 to 2020.The results revealed that:(1)a general increasing tendency from southeast to northwest was identified in the spatial distribution of desertification sensitivity.The low-sensitivity areas were mostly concentrated in the Hengduan and Nyaingqêntanglha mountains and surrounding forest and meadow areas.The high-sensitivity areas were located mainly in the Kunlun and Altun mountains and surrounding decertified areas.The center of gravity of all types of desertification-sensitive areas moved to the northwest,and the desertification sensitivity showed a decreasing trend as a whole;(2)the area of highly sensitive desertification areas decreased by 8.37%,with extreme sensitivity being the largest change among the sensitivity types.The desertification sensitivity transfer was characterized by a greater shift to lower sensitivity levels(24.56%)than to higher levels(2.03%),which demonstrated a declining trend;(3)since 1990,the change in desertification sensitivity has been dominated by the stabilizing type Ⅰ(29.30%),with the area of continuously increasing desertification sensitivity accounting for only 1.10%,indicating that the management of desertification has achieved positive results in recent years;and(4)natural factors have had a more significant impact on desertification sensitivity on the Xizang Plateau,whereas socioeconomic factors affected only localized areas.The main factors influencing desertification sensitivity were vegetation drought tolerance and aridity index.Studying spatiotemporal variations in desertification sensitivity and its influencing factors can provide a scientific foundation for developing strategies to control desertification on the Qinghai-Xizang Plateau.Dividing different desertification-sensitive areas on the basis of these patterns of change can facilitate the formulation of more targeted management and protection measures,contributing to ecological construction and sustainable economic development in the area.展开更多
Land desertification severely compromises the core function of ecosystem and significantly disrupts biodiversity.Caragana korshinskii Kom.plays a pivotal role as a critical plant resource in the restoration and ecolog...Land desertification severely compromises the core function of ecosystem and significantly disrupts biodiversity.Caragana korshinskii Kom.plays a pivotal role as a critical plant resource in the restoration and ecological reconstruction of desertified areas in Northwest China.Kytorhinus immixtus Motschulsky is the primary pest responsible for causing substantial damage to the seeds of C.korshinskii.In this study,field surveys were utilized in three distinct desertified types(lightly,moderately,and severely desertified areas)in north central Ningxia Hui Autonomous Region,Northwest China.This research was focused on investigating the population dynamics and damage rates of K.immixtus,with an emphasis on examining the relationships among K.immixtus distribution,levels of soil desertification,and associated environmental factors.The results revealed marked variations in the population distribution and abundance of K.immixtus across habitats with different degrees of desertification.Due to the sand-fixing ability of C.korshinskii,the severity of soil desertification decreased progressively from severe to moderate and light with C.korshinskii establishment.This reduction in desertification,along with habitat restoration and an increase in plant diversity,was correlated with a gradual increase in K.immixtus population size and damage rate.Generalized linear mixed model analysis revealed significantly positive correlations of soil total potassium,C.korshinskii height,maximum temperature during the survey,precipitation,and the plant species richness index with K.immixtus population.In contrast,the soil total phosphorus content,organic matter content,minimum temperature during the survey,C.korshinskii canopy width,and branch number were significantly and negatively correlated with K.immixtus population.Due to the sand-fixing capacity of C.korshinskii,the plant mitigated soil desertification,but as desertification severity decreased,habitat restoration and increased plant diversity drove a gradual increase in the population and damage rate of K.immixtus.Both biotic and abiotic factors in the habitat significantly influenced K.immixtus occurrence.To achieve the sustainable restoration of desert ecosystem,optimization of plant community structure with soil nutrient management in ecological rehabilitation is necessary to balance the benefits of sand fixation with pest risks.展开更多
Desertification poses a significant ecological threat to global sustainability,notably within arid regions such as the Tarim Basin surrounding the extensive Taklimakan Desert in Northwest China.This study used the Goo...Desertification poses a significant ecological threat to global sustainability,notably within arid regions such as the Tarim Basin surrounding the extensive Taklimakan Desert in Northwest China.This study used the Google Earth Engine(GEE)platform and Random Forest(RF)to analyze multi-temporal Landsat images to reveal desertification dynamics in the Tarim Basin spanning from 1990 to 2020.The results showed that land use types of the Tarim Basin were classified into three types:artificial oases,natural oases,and desertified land.To robustly quantify the spatiotemporal dynamics of land use,we introduced the Desertification Change Index(DCI),a novel metric specifically designed to measure the transformation sensitivity of land use types.Our analysis demonstrated that from 1990 to 2020,artificial oases showed a continuous increasing trend,while desertified land decreased significantly.Natural oases decreased during 1990–2000,then continued to grow,and showed a decreasing trend again after 2015.Moreover,natural oases have mainly been converted into desertified land and artificial oases.Artificial oases were mainly converted into natural oases,and most of desertified land was converted into natural oases.Regions with significant oasis expansion(DCI=2)were mostly concentrated within the influence radius of artificial oases.In contrast,regions with significant oasis degradation(DCI=–2)were generally farther from artificial oases.Finally,this study found that the changes in land use types of the Tarim Basin are mainly driven by human activities,which play a dual role—mitigating desertification by controlling oasis expansion and exacerbating desertification through unsustainable resource utilization.Ultimately,this research provides essential insights for policy-makers and land managers aiming to devise adaptive and sustainable desertification control measures in the Tarim Basin and similarly arid regions globally.展开更多
Tibetan alpine steppes are large and sensitive terrestrial carbon(C)reservoirs that are experiencing desertification due to global change and overgrazing,which can lead to stronger resource limitations for both above-...Tibetan alpine steppes are large and sensitive terrestrial carbon(C)reservoirs that are experiencing desertification due to global change and overgrazing,which can lead to stronger resource limitations for both above-and belowground communities.Soil nutrients,especially nitrogen(N)and phosphorus(P),are the crucial resources for plant growth and microbial metabolism.However,whether both plant and soil microbial communities in the degraded alpine steppes are limited by these soil nutrients remains unclear,which limits our understanding of the mechanisms of desertification and subsequent ecosystem restoration.Here,we evaluated potential nutrient limitations of the plant and soil microbial communities in the alpine steppe across five stages of desertification using stoichiometry-based approaches.Our results showed that soil microbial metabolism was mainly limited by C and P,and the plant N limitation and microbial C limitation were intensified while the microbial P limitation was relieved during desertification.Plant-soil-microbe interactions had significant impacts on the microbial C and P limitations,explaining 72 and 61%of the variation,respectively.Specifically,desertification ultimately affected microbial metabolic limitations by regulating soil pH,soil nutrients,and the plant N limitation.Moreover,the microbial C limitation further reduced microbial C use efficiency(CUE)with desertification,which is detrimental for organic C retention in the degraded soil.Overall,this study revealed that microbial metabolic limitations through plant-microbe interactions were the key drivers affecting soil microbial CUE,and it provided insights that can advance our knowledge of the microbial regulation of nutrient cycles and C sequestration.展开更多
As a major worldwide issue,desertification poses significant threats to ecosystem stability and long-term socioeconomic growth.Within China,the Mu Us Sandy land represents a crucial region for studying desertification...As a major worldwide issue,desertification poses significant threats to ecosystem stability and long-term socioeconomic growth.Within China,the Mu Us Sandy land represents a crucial region for studying desertification phenomena.Comprehending how desertification risks are distributed spatially and what mechanisms drive them remains fundamental for implementing effective strategies in land management and risk mitigation.Our research evaluated desertification vulnerability across the Mu Us Sandy land by applying the MEDALUS model,while investigating causal factors via geographical detector methodology.Findings indicated that territories with high desertification vulnerability extend across 71,401.7 km^(2),constituting 76.87%of the entire region,while zones facing extreme desertification hazard cover 20,578.9 km^(2)(22.16%),primarily concentrated in a band-like pattern along the western boundary of the Mu Us Sandy land.Among the four primary indicators,management quality emerged as the most significant driver of desertification susceptibility,followed by vegetation quality and soil quality.Additionally,drought resistance,land use intensity,and erosion protection were identified as the key factors driving desertification sensitivity.The investigation offers significant theoretical perspectives that can guide the formulation of enhanced strategies for controlling desertification and promoting sustainable land resource utilization within the Mu Us Sandy land region.展开更多
Desertification has had a significant impact on the ecological environment of the Yellow River Basin(YRB)in China.However,previous studies on the evaluation of the ecological environment quality(EEQ)in the YRB have pa...Desertification has had a significant impact on the ecological environment of the Yellow River Basin(YRB)in China.However,previous studies on the evaluation of the ecological environment quality(EEQ)in the YRB have paid limited attention to the indicator of desertification.It is of great significance to incorporate the desertification index into the spatiotemporal assessment of the EEQ in the YRB in order to protect the ecological environment in the region.In this study,based on multi-source remote sensing data from 91 cities in the YRB,this article proposes a desertification remote sensing ecological index(DRSEI)model,which builds upon the traditional Remote Sensing Ecological Index(RSEI)model,to analyze the spatiotemporal changes in the EEQ in the YRB from 2001 to 2021.Furthermore,using the geographic detector(GD),and geographically and temporally weighted regression(GTWR)model,the study assesses the impact of human and natural factors on the EEQ in the YRB.The research findings indicate that:(1)Compared to the traditional RSEI,the improved DRSEI shows a decreasing trend in the evaluation results of the EEQ.Among the 24 cities,the change in DRSEI exceeds 0.05 compared to RSEI,accounting for 26.37%of the YRB.The remaining 67 cities have changes within a range of less than 0.05,accounting for 73.63%of the YRB.(2)The results of the GD for individual and interactive effects reveal that rainfall and elevation have significant individual and interactive effects on the EEQ.Furthermore,after the interaction with natural factors,the explanatory power of human factors gradually increases over time.The spatial heterogeneity results of GTWR demonstrate that rainfall has a strong direct positive impact on the EEQ,accounting for 98.90%of the influence,while temperature exhibits a more pronounced direct inhibitory effect,accounting for 76.92%of the influence.Human activities have a strong negative impact on the EEQ and a weak positive impact.展开更多
Rapid increase in desertification is an environ-mental concern,especially for the health and sustainabil-ity of ecosystems in changing climates.How ecosystems respond to such changes may be partially understood by stu...Rapid increase in desertification is an environ-mental concern,especially for the health and sustainabil-ity of ecosystems in changing climates.How ecosystems respond to such changes may be partially understood by studying interactions and performance of critically impor-tant groups such as soil fungi functional groups.This study investigated variations in diversities of three soil fungi functional guilds(saprotrophic,symbiotic,pathogenic)and influencing abiotic factors in a Pinus densata forest on the southeast Tibetan Plateau where desertification is intense.The results indicate desertification significantly decreased the proportion of dominant fungal guild-symbiotic fungi(mean relative abundance decreasing from 97.0%to 68.3%),in contrast to saprotrophic fungi(increasing from 2.7%to 25.7%)and pathogenic(from 0.3%to 5.9%).Soil pH had the most significant impact on fungal community structure and negatively correlated with symbiotic fungal richness,which was significantly lower in arid soils,and positively correlated with saprotrophic and pathogenic fungal alpha-diversity,which were abundant.Different community struc-tures and regulators of the three fungi communities were observed,with pH,total phosphorus and ammonium(NH_(4)^(+))as the main determinants.This study links the biotic and abi-otic components during desertification and the interactions between them,and may be used as indicators of ecosystem health and for amendments to mitigate the effects of a chang-ing climate.展开更多
Increased soil erosion as a consequence of karst rocky desertification(KRD)reduces soil quality and plant diversity.Premna puberula Pamp.is a perennial understory shrub that can adapt to the harsh environment of KRD a...Increased soil erosion as a consequence of karst rocky desertification(KRD)reduces soil quality and plant diversity.Premna puberula Pamp.is a perennial understory shrub that can adapt to the harsh environment of KRD and has potential value for KRD environmental restoration.We measure morphological and photosynthetic characteristics,nutrient accumulation,and soil physical and chemical properties of two-year-old P.puberula planted in KRD habitat and non-rocky desertification areas,and investigate how it adapts to this habitat.In KRD areas,P.puberula reduces aboveground water loss by decreasing leaf area,stomatal conductance,and transpiration rate,while increasing leaf thickness,root length and number,and increases belowground biomass to absorb more water and nutrients.In KRD areas,drought leads to decreased leaf water content,stomatal conductance,intercellular CO_(2) concentration,and chlorophyll content,and decreased photosynthetic rate.Soluble sugar and protein contents increase in KRD areas in response to water stress,but pectin and flavonoid contents decrease.Correlation analysis reveals that leaf area and thickness are important functional traits that affect leaf water content and photosynthesis.Totals of leaf carbon,nitrogen,and phosphorus,along with C:N,C:P,and N:P ratios,are coupled with leaf photosynthetic characteristics and root development.Redundancy analysis reveals that available K and P,and total P,K,and N in soil mainly influence the differences in plant functional traits,explaining 95.8%,95.5%,91.1%,85.8%,and 74%of variation,respectively.We hypothesize that P.puberula reduces aboveground productivity to maintain its water balance,and acquires more water and nutrients by increasing belowground biomass.It indicates that this species adapts to arid KRD environments.展开更多
Assessment of land sensitivity to desertification is an important step to support desertification monitoring and control.Based on the Mediterranean Desertification and Land Use(MEDALUS)model,we defined four quality in...Assessment of land sensitivity to desertification is an important step to support desertification monitoring and control.Based on the Mediterranean Desertification and Land Use(MEDALUS)model,we defined four quality indicators(soil,climate,vegetation and management)to evaluate the sensitivity of land in northern China to desertification.We improved MEDALUS via excluding cities from the areas at risk of desertification by means of defining a threshold value for population density.The framework,validated in northern China,further optimizes the model to link priority areas and land restoration programmed to support desertification control.We found that the four indicators influenced and restricted each other,which jointly affected the distribution of desertification sensitivity in northern China.The spatial distribution of sensitivity in northern China showed large regional differences,with clear boundaries and concentrated distributions of regions with high and low sensitivity;the overall sensitivity decreased,with some areas rated as having moderate,severe,and extremely severe sensitivity changing to slight sensitivity;and the influence weight was much higher for the management quality index than for the climate,vegetation,and soil indexes.This suggests that management was the main factor that affected desertification sensitivity in northern China,and that climate factors exacerbated sensitivity,but the factors that are driving the spatial heterogeneity of the influencing factors need further study。展开更多
Based on the general requirements of the coordinated development of"ecological livable"and"affluent life"in the rural revitalization strategy,the evaluation index system of desertification control ...Based on the general requirements of the coordinated development of"ecological livable"and"affluent life"in the rural revitalization strategy,the evaluation index system of desertification control was constructed,the interaction between desertification control and regional social economy and the internal space-time coordination mechanism were explored,and the quality of desertification control and its coordination degree with regional economic development were quantitatively analyzed.The decoupling mechanism of desertification governance society economy system were analyzed,and the high level for the government to promote desertification governance,constructing ecological economy coordinated development pattern to provide decision basis to Xizang desertification governance-social economic system interaction and coupling coordination development as the research object,introducing the coupling decoupling model to measure the coupling coordination model and system coordination and decoupling decoupling.Desertification control in Xizang shows a trend of gradual improvement,but the overall level is still not high and there is a lot of room for optimization.The coupling coordination degree of desertification control-social and economic system is in a steady fluctuation trend,rising from D value less than 0.55 in 2004 to 0.87 in 2018,in a state of coordinated development(good),and grey prediction analysis shows that D value is in a continuous rise.The coupling coordination degree of the six prefecture-level cities in Xizang and Ngari region is different in time and space,but the overall development trend is coordinated.The development index of desertification control and the socio-economic development index show the interaction of strong decoupling,strong negative decoupling and weak decoupling,and there are interaction effects of desertification control,economic development and social development at different scales.展开更多
In this paper,managed forest(MF)and natural forest(NF)in the Huajiang Demonstration Zone of Guanling,Guizhou were selected as research objects,and cropland(CL)was taken as control.High-throughput sequencing technology...In this paper,managed forest(MF)and natural forest(NF)in the Huajiang Demonstration Zone of Guanling,Guizhou were selected as research objects,and cropland(CL)was taken as control.High-throughput sequencing technology was used to study the characteristics of fungal community composition and species diversity in the surface(0-10 cm)soil of each restoration measure,in order to reveal the dominant soil fungal groups and fungal community composition in karst rocky desertification areas,which was conducive to a more comprehensive understanding of the soil conditions of different vegetation restoration measures.Research has shown that vegetation restoration significantly affected the diversity of soil fungal community,with significant increases in Sob index,Ace index,and Chao index.The vegetation restoration has significantly changed the composition of fungal community.The dominant fungi in the CL topsoil are Sordariomycetes(62.28%),Dothideomycetes(12.34%),and Eurotiomycetes(9.12%);the dominant fungi in the MF soil are Sordariomycetes(45.05%),Dothideomycetes(14.74%),and Mortierellomycetes(10.40%);the dominant fungi in the NF soil are unclassified fungal community(26.38%),Sordariomycetes(19.78%),and Agaricomycetes(13.82%).Vegetation restoration has changed the key fungal groups in the soil.Sordariomycetes,Fusarium,and Setophoma are the key dominant fungal groups in CL soil;Dioszegia is key dominant fungal group in MF soil;c_unclassified_k_Fungi,p_unclassified_k_Fungi,o_unclassified_k_Fungi,f_unclassified_k_Fungi,g_unclassified_k_Fungi,Teichospora,and Diaporthe are key dominant fungal groups in NF soil.展开更多
Desertification research in arid and semi-arid regions has always been actively pursued.In China,the problem of desertification in Xinjiang has also received extensive attention.Due to its unique geography,many schola...Desertification research in arid and semi-arid regions has always been actively pursued.In China,the problem of desertification in Xinjiang has also received extensive attention.Due to its unique geography,many scholars have conducted corresponding research on the desertification status of Xinjiang.In this paper,we comprehensively reviewed desertification in Xinjiang,and compared the underlying mechanisms of desertification and the status of desertification conditions after the implementation of ecological control projects.On a larger scale,desertification in Xinjiang can be divided into soil salinization inside oases and sandy desertification on the edges of oases.Human activities are considered the main cause of desertification,but natural factors also contribute to varying degrees.Research on the mechanisms of desertification has effectively curbed the development of desertification,but unreasonable use of land resources accelerates the risk of desertification.For desertification control,there are several key points.First,desertification monitoring and the early warning of desertification expansion should be strengthened.Second,monitoring and reversing soil salinization also play an important role in the interruption of desertification process.It is very effective to control soil salinization through biological and chemical methods.Third,the management of water resources is also essential,because unreasonable utilization of water resources is one of the main reasons for the expansion of desertification in Xinjiang.Due to the unreasonable utilization of water resources,the lower reaches of the Tarim River are cut off,which leads to a series of vicious cycles,such as the deterioration of ecological environment on both sides of the river and the worsening of desertification.However,in recent years,various desertification control projects implemented in Xinjiang according to the conditions of different regions have achieved remarkable results.For future studies,research on the stability of desert-oasis transition zone is also significantly essential,because such investigations can help to assess the risk of degradation and control desertification on a relatively large scale.展开更多
[Objective] The research aimed to study change law of phosphorus content of soil in karst rocky desertification region(KRD) during eco-restoration process such as Northwest Guangxi Province.[Method] The soil samples w...[Objective] The research aimed to study change law of phosphorus content of soil in karst rocky desertification region(KRD) during eco-restoration process such as Northwest Guangxi Province.[Method] The soil samples were collected from typical KRD in Pingguo County and Yizhou City.The determining quotas of different soil samples such as soil total phosphorus content and available phosphorus content were detected,in addition the soil total phosphorus content,available phosphorus content, urease activity, catalase activity and organic matter content in different soil samples were analyzed comparatively.[Result] Aspect,vegetation type and recovery time generated obviously influences on phosphorus contents in different soil samples.The concrete influence order was listed as follow: phosphorus content in soil of south slope was higher than that in soil of north slope;phosphorus content in soil where Zenia insignis Chun was planted was higher than that in soil of closed forest and that of soil where Dendrocalamus minor Var. amoen was planted,additionally,phosphorus increased with recovery time. Urease activity could be used as a monitoring index of soil fertility because it is related to the change of phosphorus content.[Conclusion] The soil of karst rocky desertification region in Northwest Guangxi Province could be recovered gradually if excessive human disturbance was stopped.If proper natural method of recovery promoted by human was taken,the recovery would reach a better result.展开更多
[Objective] To extract desertification information of Hulun Buir region based on MODIS image data. [Method] Based on MODIS image data with the spatial res- olution of 1 km, 5 indicators which could reflect different d...[Objective] To extract desertification information of Hulun Buir region based on MODIS image data. [Method] Based on MODIS image data with the spatial res- olution of 1 km, 5 indicators which could reflect different desertification features were selected to conduct inversion. The desertification information of Hulun Buir region was extracted by decision tree classification. [Result] The desertification area of Hu- lun Buir region is 33 862 km2, accounting for 24% of the total area, and it is mainly dominated by sandiness desertification. Though field verification and mining point validation of high-resolution interpretation data, the overall accuracy of this evaluation is above 89%. [Conclusion] Evaluation method used in this study is not only effectively for large scale regional desertification monitoring but also has a better evaluation performance.展开更多
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
In the Haishi Park Demonstration Base of Zhongliang Mountain in Chongqing, ecological restoration modes were established based on growth status of local plants and other natural environmental conditions, including for...In the Haishi Park Demonstration Base of Zhongliang Mountain in Chongqing, ecological restoration modes were established based on growth status of local plants and other natural environmental conditions, including forestry ecology, tourism ecology, agricultural ecology as well as the combined mode of various ecological types.展开更多
Based on the definition of desertification adopted by United Nations Convention to Combat Desertification in Those Countries Experiencing Serious Drought and/or Desertification,particularly in Africa, first,the pat...Based on the definition of desertification adopted by United Nations Convention to Combat Desertification in Those Countries Experiencing Serious Drought and/or Desertification,particularly in Africa, first,the patterns of desertification in China are introduced.Second,desertification assessment indicator system that used in China is presented.It includes:(1)climate classification;(2)classification of land use;(3)classification of desertification patterns which include wind erosion,water erosion,salinization,and grassland degradation;(4)grading index of desertification that includes grading index of desertification caused by wind erosion,desertification caused by water erosion,desertification caused by salinization,indicators of grassland degradation classification.At last,some detailed factors that can be used as indicators in desertification assessment are discussed.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
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
基金supported by the State Key Research and Development Program of China(2023YFF1305304)the Open Bidding for Selecting the Best Candidates Project of Inner Mongolia Autonomous Region(2024JBGS0020).
文摘Desertification is a global crucial ecological and environmental issue,and China is among the countries most seriously affected by desertification.In recent decades,numerous independent studies on desertification dynamics have been carried out using remote sensing technology,but there has been a lack of systematic research on desertification trends in China.This study employed the meta-analysis to integrate the findings of 140 published research cases and examined the dynamics of desertification in the eight major deserts,four major sandy lands,and their surrounding areas in China from 1970 to 2019,with a comparative analysis of differences between the eastern(including the Mu Us Sandy Land,the Otindag Sandy Land,the Hulunbuir Sandy Land,the Horqin Sandy Land,and the Hobq Desert)and western(including the Taklimakan Desert,the Gurbantunggut Desert,the Kumtagh Desert,the Ulan Buh Desert,the Qaidam Basin Desert,the Badain Jaran Desert,and the Tengger Desert)regions.The results revealed that from 1970 to 2019,desertification first expanded and then reversed in the whole region.Specifically,desertification expanded from 1980 to 1999 and reversed after 2000.The desertification trend exhibited distinct spatio-temporal variations between the eastern and western regions.From 1970 to 2019,the western region experienced relatively minor changes in desertified land area compared to the eastern region.In the context of global climate change,beneficial climatic conditions and ecological construction projects played a crucial role in reversing desertification.These findings provide valuable insights for understanding the development patterns of desertification in the most representative deserts and sandy lands in China and formulating effective desertification control strategies.
基金funded by the National Natural Science Foundation of China(42371219)the Key Natural Science Foundation of Gansu Province(24JRRA135)the Oasis Scientific Research Achievements Breakthrough Action Plan Project of Northwest Normal University(NWNU-LZKX-202302).
文摘Due to irrational human activities and extreme climate,the Qinghai-Xizang Plateau,China,faces a serious threat of desertification.Desertification has a detrimental effect on the ecological environment and socioeconomic development.In this study,the desertification sensitivity index(DSI)model was established by integrating the spatial distance model and environmentally sensitive area index evaluation method,and then the model was used to quantitatively analyze the spatial and temporal characteristics of desertification sensitivity of the Qinghai-Xizang Plateau from 1990 to 2020.The results revealed that:(1)a general increasing tendency from southeast to northwest was identified in the spatial distribution of desertification sensitivity.The low-sensitivity areas were mostly concentrated in the Hengduan and Nyaingqêntanglha mountains and surrounding forest and meadow areas.The high-sensitivity areas were located mainly in the Kunlun and Altun mountains and surrounding decertified areas.The center of gravity of all types of desertification-sensitive areas moved to the northwest,and the desertification sensitivity showed a decreasing trend as a whole;(2)the area of highly sensitive desertification areas decreased by 8.37%,with extreme sensitivity being the largest change among the sensitivity types.The desertification sensitivity transfer was characterized by a greater shift to lower sensitivity levels(24.56%)than to higher levels(2.03%),which demonstrated a declining trend;(3)since 1990,the change in desertification sensitivity has been dominated by the stabilizing type Ⅰ(29.30%),with the area of continuously increasing desertification sensitivity accounting for only 1.10%,indicating that the management of desertification has achieved positive results in recent years;and(4)natural factors have had a more significant impact on desertification sensitivity on the Xizang Plateau,whereas socioeconomic factors affected only localized areas.The main factors influencing desertification sensitivity were vegetation drought tolerance and aridity index.Studying spatiotemporal variations in desertification sensitivity and its influencing factors can provide a scientific foundation for developing strategies to control desertification on the Qinghai-Xizang Plateau.Dividing different desertification-sensitive areas on the basis of these patterns of change can facilitate the formulation of more targeted management and protection measures,contributing to ecological construction and sustainable economic development in the area.
基金funded by the National Natural Science Foundation of China(31860619,31560611)the Natural Science Foundation of Ningxia Hui Autonomous Region,China(2021AAC02009).
文摘Land desertification severely compromises the core function of ecosystem and significantly disrupts biodiversity.Caragana korshinskii Kom.plays a pivotal role as a critical plant resource in the restoration and ecological reconstruction of desertified areas in Northwest China.Kytorhinus immixtus Motschulsky is the primary pest responsible for causing substantial damage to the seeds of C.korshinskii.In this study,field surveys were utilized in three distinct desertified types(lightly,moderately,and severely desertified areas)in north central Ningxia Hui Autonomous Region,Northwest China.This research was focused on investigating the population dynamics and damage rates of K.immixtus,with an emphasis on examining the relationships among K.immixtus distribution,levels of soil desertification,and associated environmental factors.The results revealed marked variations in the population distribution and abundance of K.immixtus across habitats with different degrees of desertification.Due to the sand-fixing ability of C.korshinskii,the severity of soil desertification decreased progressively from severe to moderate and light with C.korshinskii establishment.This reduction in desertification,along with habitat restoration and an increase in plant diversity,was correlated with a gradual increase in K.immixtus population size and damage rate.Generalized linear mixed model analysis revealed significantly positive correlations of soil total potassium,C.korshinskii height,maximum temperature during the survey,precipitation,and the plant species richness index with K.immixtus population.In contrast,the soil total phosphorus content,organic matter content,minimum temperature during the survey,C.korshinskii canopy width,and branch number were significantly and negatively correlated with K.immixtus population.Due to the sand-fixing capacity of C.korshinskii,the plant mitigated soil desertification,but as desertification severity decreased,habitat restoration and increased plant diversity drove a gradual increase in the population and damage rate of K.immixtus.Both biotic and abiotic factors in the habitat significantly influenced K.immixtus occurrence.To achieve the sustainable restoration of desert ecosystem,optimization of plant community structure with soil nutrient management in ecological rehabilitation is necessary to balance the benefits of sand fixation with pest risks.
基金supported by the Third Xinjiang Scientific Expedition and Research Program-Investigation and Risk Assessment of Drought and Aeolian Disasters in Tarim River Basin(2021xjkk0300)the Xinjiang Tianshan Talent Program(2022TSYCLJ0002)the Basic Frontier Project of Xinjiang Institute of Ecology and Geography,Chinese Academy of Sciences(E3500201).
文摘Desertification poses a significant ecological threat to global sustainability,notably within arid regions such as the Tarim Basin surrounding the extensive Taklimakan Desert in Northwest China.This study used the Google Earth Engine(GEE)platform and Random Forest(RF)to analyze multi-temporal Landsat images to reveal desertification dynamics in the Tarim Basin spanning from 1990 to 2020.The results showed that land use types of the Tarim Basin were classified into three types:artificial oases,natural oases,and desertified land.To robustly quantify the spatiotemporal dynamics of land use,we introduced the Desertification Change Index(DCI),a novel metric specifically designed to measure the transformation sensitivity of land use types.Our analysis demonstrated that from 1990 to 2020,artificial oases showed a continuous increasing trend,while desertified land decreased significantly.Natural oases decreased during 1990–2000,then continued to grow,and showed a decreasing trend again after 2015.Moreover,natural oases have mainly been converted into desertified land and artificial oases.Artificial oases were mainly converted into natural oases,and most of desertified land was converted into natural oases.Regions with significant oasis expansion(DCI=2)were mostly concentrated within the influence radius of artificial oases.In contrast,regions with significant oasis degradation(DCI=–2)were generally farther from artificial oases.Finally,this study found that the changes in land use types of the Tarim Basin are mainly driven by human activities,which play a dual role—mitigating desertification by controlling oasis expansion and exacerbating desertification through unsustainable resource utilization.Ultimately,this research provides essential insights for policy-makers and land managers aiming to devise adaptive and sustainable desertification control measures in the Tarim Basin and similarly arid regions globally.
基金supported by the National Key Research and Development Program of China(2023YFF1304304)。
文摘Tibetan alpine steppes are large and sensitive terrestrial carbon(C)reservoirs that are experiencing desertification due to global change and overgrazing,which can lead to stronger resource limitations for both above-and belowground communities.Soil nutrients,especially nitrogen(N)and phosphorus(P),are the crucial resources for plant growth and microbial metabolism.However,whether both plant and soil microbial communities in the degraded alpine steppes are limited by these soil nutrients remains unclear,which limits our understanding of the mechanisms of desertification and subsequent ecosystem restoration.Here,we evaluated potential nutrient limitations of the plant and soil microbial communities in the alpine steppe across five stages of desertification using stoichiometry-based approaches.Our results showed that soil microbial metabolism was mainly limited by C and P,and the plant N limitation and microbial C limitation were intensified while the microbial P limitation was relieved during desertification.Plant-soil-microbe interactions had significant impacts on the microbial C and P limitations,explaining 72 and 61%of the variation,respectively.Specifically,desertification ultimately affected microbial metabolic limitations by regulating soil pH,soil nutrients,and the plant N limitation.Moreover,the microbial C limitation further reduced microbial C use efficiency(CUE)with desertification,which is detrimental for organic C retention in the degraded soil.Overall,this study revealed that microbial metabolic limitations through plant-microbe interactions were the key drivers affecting soil microbial CUE,and it provided insights that can advance our knowledge of the microbial regulation of nutrient cycles and C sequestration.
基金the National Natural Science Foundation of China(Grant No.42301336)the Open Research Fund of Henan Provincial Key Laboratory of Hydrosphere and Watershed Water Security(Grant No.HWWSF202302).
文摘As a major worldwide issue,desertification poses significant threats to ecosystem stability and long-term socioeconomic growth.Within China,the Mu Us Sandy land represents a crucial region for studying desertification phenomena.Comprehending how desertification risks are distributed spatially and what mechanisms drive them remains fundamental for implementing effective strategies in land management and risk mitigation.Our research evaluated desertification vulnerability across the Mu Us Sandy land by applying the MEDALUS model,while investigating causal factors via geographical detector methodology.Findings indicated that territories with high desertification vulnerability extend across 71,401.7 km^(2),constituting 76.87%of the entire region,while zones facing extreme desertification hazard cover 20,578.9 km^(2)(22.16%),primarily concentrated in a band-like pattern along the western boundary of the Mu Us Sandy land.Among the four primary indicators,management quality emerged as the most significant driver of desertification susceptibility,followed by vegetation quality and soil quality.Additionally,drought resistance,land use intensity,and erosion protection were identified as the key factors driving desertification sensitivity.The investigation offers significant theoretical perspectives that can guide the formulation of enhanced strategies for controlling desertification and promoting sustainable land resource utilization within the Mu Us Sandy land region.
基金supported by the National Science Foundation of China (Grant Number: 72004116)the Hubei Social Science Foundation (Grant NO. 2022CFB292)
文摘Desertification has had a significant impact on the ecological environment of the Yellow River Basin(YRB)in China.However,previous studies on the evaluation of the ecological environment quality(EEQ)in the YRB have paid limited attention to the indicator of desertification.It is of great significance to incorporate the desertification index into the spatiotemporal assessment of the EEQ in the YRB in order to protect the ecological environment in the region.In this study,based on multi-source remote sensing data from 91 cities in the YRB,this article proposes a desertification remote sensing ecological index(DRSEI)model,which builds upon the traditional Remote Sensing Ecological Index(RSEI)model,to analyze the spatiotemporal changes in the EEQ in the YRB from 2001 to 2021.Furthermore,using the geographic detector(GD),and geographically and temporally weighted regression(GTWR)model,the study assesses the impact of human and natural factors on the EEQ in the YRB.The research findings indicate that:(1)Compared to the traditional RSEI,the improved DRSEI shows a decreasing trend in the evaluation results of the EEQ.Among the 24 cities,the change in DRSEI exceeds 0.05 compared to RSEI,accounting for 26.37%of the YRB.The remaining 67 cities have changes within a range of less than 0.05,accounting for 73.63%of the YRB.(2)The results of the GD for individual and interactive effects reveal that rainfall and elevation have significant individual and interactive effects on the EEQ.Furthermore,after the interaction with natural factors,the explanatory power of human factors gradually increases over time.The spatial heterogeneity results of GTWR demonstrate that rainfall has a strong direct positive impact on the EEQ,accounting for 98.90%of the influence,while temperature exhibits a more pronounced direct inhibitory effect,accounting for 76.92%of the influence.Human activities have a strong negative impact on the EEQ and a weak positive impact.
基金supported by the Strategic Priority Research Program of the Chinese Academy of Sciences(No.XDB31000000)the Second Tibetan Plateau Scientific Expedition and Research Program(No.2019QZKK0307)+1 种基金the Key Project of the Open Competition in Jiangsu Forestry(No.LYKJ[2022]01)the Jiangsu Social Development Project(BE2022792).
文摘Rapid increase in desertification is an environ-mental concern,especially for the health and sustainabil-ity of ecosystems in changing climates.How ecosystems respond to such changes may be partially understood by studying interactions and performance of critically impor-tant groups such as soil fungi functional groups.This study investigated variations in diversities of three soil fungi functional guilds(saprotrophic,symbiotic,pathogenic)and influencing abiotic factors in a Pinus densata forest on the southeast Tibetan Plateau where desertification is intense.The results indicate desertification significantly decreased the proportion of dominant fungal guild-symbiotic fungi(mean relative abundance decreasing from 97.0%to 68.3%),in contrast to saprotrophic fungi(increasing from 2.7%to 25.7%)and pathogenic(from 0.3%to 5.9%).Soil pH had the most significant impact on fungal community structure and negatively correlated with symbiotic fungal richness,which was significantly lower in arid soils,and positively correlated with saprotrophic and pathogenic fungal alpha-diversity,which were abundant.Different community struc-tures and regulators of the three fungi communities were observed,with pH,total phosphorus and ammonium(NH_(4)^(+))as the main determinants.This study links the biotic and abi-otic components during desertification and the interactions between them,and may be used as indicators of ecosystem health and for amendments to mitigate the effects of a chang-ing climate.
基金supported by the Key Core Technology Research Project for Mountainous Agriculture in Guizhou(GZNYGJHX-2023011)the Science and Technology Support Plan Project of Guizhou(2018-2797)+2 种基金the Major Special Project of Science and Technology Program in Guizhou(2017-5411-06)the Construction Project of State Engineering Technology Institute for Karst Desertification Control of China(2012FU125X13)the Construction Project of Modern Industry Technology system of traditional Chinese Medicinal Materials in Guizhou(GZCYTX-02).
文摘Increased soil erosion as a consequence of karst rocky desertification(KRD)reduces soil quality and plant diversity.Premna puberula Pamp.is a perennial understory shrub that can adapt to the harsh environment of KRD and has potential value for KRD environmental restoration.We measure morphological and photosynthetic characteristics,nutrient accumulation,and soil physical and chemical properties of two-year-old P.puberula planted in KRD habitat and non-rocky desertification areas,and investigate how it adapts to this habitat.In KRD areas,P.puberula reduces aboveground water loss by decreasing leaf area,stomatal conductance,and transpiration rate,while increasing leaf thickness,root length and number,and increases belowground biomass to absorb more water and nutrients.In KRD areas,drought leads to decreased leaf water content,stomatal conductance,intercellular CO_(2) concentration,and chlorophyll content,and decreased photosynthetic rate.Soluble sugar and protein contents increase in KRD areas in response to water stress,but pectin and flavonoid contents decrease.Correlation analysis reveals that leaf area and thickness are important functional traits that affect leaf water content and photosynthesis.Totals of leaf carbon,nitrogen,and phosphorus,along with C:N,C:P,and N:P ratios,are coupled with leaf photosynthetic characteristics and root development.Redundancy analysis reveals that available K and P,and total P,K,and N in soil mainly influence the differences in plant functional traits,explaining 95.8%,95.5%,91.1%,85.8%,and 74%of variation,respectively.We hypothesize that P.puberula reduces aboveground productivity to maintain its water balance,and acquires more water and nutrients by increasing belowground biomass.It indicates that this species adapts to arid KRD environments.
基金the National Key Research and Development Program of China(2020YFA0608404)the National Nature Science Foundation of China(41101006).
文摘Assessment of land sensitivity to desertification is an important step to support desertification monitoring and control.Based on the Mediterranean Desertification and Land Use(MEDALUS)model,we defined four quality indicators(soil,climate,vegetation and management)to evaluate the sensitivity of land in northern China to desertification.We improved MEDALUS via excluding cities from the areas at risk of desertification by means of defining a threshold value for population density.The framework,validated in northern China,further optimizes the model to link priority areas and land restoration programmed to support desertification control.We found that the four indicators influenced and restricted each other,which jointly affected the distribution of desertification sensitivity in northern China.The spatial distribution of sensitivity in northern China showed large regional differences,with clear boundaries and concentrated distributions of regions with high and low sensitivity;the overall sensitivity decreased,with some areas rated as having moderate,severe,and extremely severe sensitivity changing to slight sensitivity;and the influence weight was much higher for the management quality index than for the climate,vegetation,and soil indexes.This suggests that management was the main factor that affected desertification sensitivity in northern China,and that climate factors exacerbated sensitivity,but the factors that are driving the spatial heterogeneity of the influencing factors need further study。
基金supported by the Beijing Social Science Foundation Project(Grant No.18YJB011)the Ministry of Education Humanities and Social Science Research Fund for Youth Project(Grant No.20YJA790059)+2 种基金the National Social Science Foundation of China(Grant No.20FGLB022)the General Project of National Social Science Foundation of China(Grant No.19BGL052)the Innovation and Entrepreneurship Project of Beijing Forestry University(Grant No.X202110022111).
文摘Based on the general requirements of the coordinated development of"ecological livable"and"affluent life"in the rural revitalization strategy,the evaluation index system of desertification control was constructed,the interaction between desertification control and regional social economy and the internal space-time coordination mechanism were explored,and the quality of desertification control and its coordination degree with regional economic development were quantitatively analyzed.The decoupling mechanism of desertification governance society economy system were analyzed,and the high level for the government to promote desertification governance,constructing ecological economy coordinated development pattern to provide decision basis to Xizang desertification governance-social economic system interaction and coupling coordination development as the research object,introducing the coupling decoupling model to measure the coupling coordination model and system coordination and decoupling decoupling.Desertification control in Xizang shows a trend of gradual improvement,but the overall level is still not high and there is a lot of room for optimization.The coupling coordination degree of desertification control-social and economic system is in a steady fluctuation trend,rising from D value less than 0.55 in 2004 to 0.87 in 2018,in a state of coordinated development(good),and grey prediction analysis shows that D value is in a continuous rise.The coupling coordination degree of the six prefecture-level cities in Xizang and Ngari region is different in time and space,but the overall development trend is coordinated.The development index of desertification control and the socio-economic development index show the interaction of strong decoupling,strong negative decoupling and weak decoupling,and there are interaction effects of desertification control,economic development and social development at different scales.
基金Supported by National Natural Science Foundation of China (42177446,41601584)Guizhou Provincial Science and Technology Fund (Qiankehe[2017]1417)Guizhou Normal University (Qianshixinmiao[2022]28).
文摘In this paper,managed forest(MF)and natural forest(NF)in the Huajiang Demonstration Zone of Guanling,Guizhou were selected as research objects,and cropland(CL)was taken as control.High-throughput sequencing technology was used to study the characteristics of fungal community composition and species diversity in the surface(0-10 cm)soil of each restoration measure,in order to reveal the dominant soil fungal groups and fungal community composition in karst rocky desertification areas,which was conducive to a more comprehensive understanding of the soil conditions of different vegetation restoration measures.Research has shown that vegetation restoration significantly affected the diversity of soil fungal community,with significant increases in Sob index,Ace index,and Chao index.The vegetation restoration has significantly changed the composition of fungal community.The dominant fungi in the CL topsoil are Sordariomycetes(62.28%),Dothideomycetes(12.34%),and Eurotiomycetes(9.12%);the dominant fungi in the MF soil are Sordariomycetes(45.05%),Dothideomycetes(14.74%),and Mortierellomycetes(10.40%);the dominant fungi in the NF soil are unclassified fungal community(26.38%),Sordariomycetes(19.78%),and Agaricomycetes(13.82%).Vegetation restoration has changed the key fungal groups in the soil.Sordariomycetes,Fusarium,and Setophoma are the key dominant fungal groups in CL soil;Dioszegia is key dominant fungal group in MF soil;c_unclassified_k_Fungi,p_unclassified_k_Fungi,o_unclassified_k_Fungi,f_unclassified_k_Fungi,g_unclassified_k_Fungi,Teichospora,and Diaporthe are key dominant fungal groups in NF soil.
基金the National Natural Science Foundation of China(41971017,41861144020)the Double Track Implementation Mechanism for Combating Desertification in China and the Experiences-Sharing in the Affected Countries along the Belt and Road Region(ANSO-SBA-2021-06).
文摘Desertification research in arid and semi-arid regions has always been actively pursued.In China,the problem of desertification in Xinjiang has also received extensive attention.Due to its unique geography,many scholars have conducted corresponding research on the desertification status of Xinjiang.In this paper,we comprehensively reviewed desertification in Xinjiang,and compared the underlying mechanisms of desertification and the status of desertification conditions after the implementation of ecological control projects.On a larger scale,desertification in Xinjiang can be divided into soil salinization inside oases and sandy desertification on the edges of oases.Human activities are considered the main cause of desertification,but natural factors also contribute to varying degrees.Research on the mechanisms of desertification has effectively curbed the development of desertification,but unreasonable use of land resources accelerates the risk of desertification.For desertification control,there are several key points.First,desertification monitoring and the early warning of desertification expansion should be strengthened.Second,monitoring and reversing soil salinization also play an important role in the interruption of desertification process.It is very effective to control soil salinization through biological and chemical methods.Third,the management of water resources is also essential,because unreasonable utilization of water resources is one of the main reasons for the expansion of desertification in Xinjiang.Due to the unreasonable utilization of water resources,the lower reaches of the Tarim River are cut off,which leads to a series of vicious cycles,such as the deterioration of ecological environment on both sides of the river and the worsening of desertification.However,in recent years,various desertification control projects implemented in Xinjiang according to the conditions of different regions have achieved remarkable results.For future studies,research on the stability of desert-oasis transition zone is also significantly essential,because such investigations can help to assess the risk of degradation and control desertification on a relatively large scale.
文摘[Objective] The research aimed to study change law of phosphorus content of soil in karst rocky desertification region(KRD) during eco-restoration process such as Northwest Guangxi Province.[Method] The soil samples were collected from typical KRD in Pingguo County and Yizhou City.The determining quotas of different soil samples such as soil total phosphorus content and available phosphorus content were detected,in addition the soil total phosphorus content,available phosphorus content, urease activity, catalase activity and organic matter content in different soil samples were analyzed comparatively.[Result] Aspect,vegetation type and recovery time generated obviously influences on phosphorus contents in different soil samples.The concrete influence order was listed as follow: phosphorus content in soil of south slope was higher than that in soil of north slope;phosphorus content in soil where Zenia insignis Chun was planted was higher than that in soil of closed forest and that of soil where Dendrocalamus minor Var. amoen was planted,additionally,phosphorus increased with recovery time. Urease activity could be used as a monitoring index of soil fertility because it is related to the change of phosphorus content.[Conclusion] The soil of karst rocky desertification region in Northwest Guangxi Province could be recovered gradually if excessive human disturbance was stopped.If proper natural method of recovery promoted by human was taken,the recovery would reach a better result.
基金Supported by the Special Fundation of China Geological Survey(1212010911084)~~
文摘[Objective] To extract desertification information of Hulun Buir region based on MODIS image data. [Method] Based on MODIS image data with the spatial res- olution of 1 km, 5 indicators which could reflect different desertification features were selected to conduct inversion. The desertification information of Hulun Buir region was extracted by decision tree classification. [Result] The desertification area of Hu- lun Buir region is 33 862 km2, accounting for 24% of the total area, and it is mainly dominated by sandiness desertification. Though field verification and mining point validation of high-resolution interpretation data, the overall accuracy of this evaluation is above 89%. [Conclusion] Evaluation method used in this study is not only effectively for large scale regional desertification monitoring but also has a better evaluation performance.
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.
文摘In the Haishi Park Demonstration Base of Zhongliang Mountain in Chongqing, ecological restoration modes were established based on growth status of local plants and other natural environmental conditions, including forestry ecology, tourism ecology, agricultural ecology as well as the combined mode of various ecological types.
文摘Based on the definition of desertification adopted by United Nations Convention to Combat Desertification in Those Countries Experiencing Serious Drought and/or Desertification,particularly in Africa, first,the patterns of desertification in China are introduced.Second,desertification assessment indicator system that used in China is presented.It includes:(1)climate classification;(2)classification of land use;(3)classification of desertification patterns which include wind erosion,water erosion,salinization,and grassland degradation;(4)grading index of desertification that includes grading index of desertification caused by wind erosion,desertification caused by water erosion,desertification caused by salinization,indicators of grassland degradation classification.At last,some detailed factors that can be used as indicators in desertification assessment are discussed.
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 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.