Interaction and coordinated development between desertification control and social economy in Xizang,China

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.

Preliminary Study on the Ecological Agriculture Development Model of"Pennisetum sineseRoxb-Rocky Desertification Control-Edible Mushrooms"in Guizhou Province

In Guizhou Province, the area of rocky desertification land is 3.023 8 million hm^2, accounting for 17.16% of total area of land in the province. Rocky desertification is the most important ecological problem that restricts the economic and social development in Guizhou, so the primary task of ecological construction in Guizhou Province is to curb rocky desertification. How to effectively, efficiently and persistently use rocky desertification land is not only the key to the improvement of ecological environment, but also an urgent problem solved for local people's survival and anti-poverty. Due to having developed roots, growing fast, high yield of grass, strong resistance to drought, and high regeneration capacity, Pennisetum sinese Roxb has become a new method to control rocky desertification. How to use P. sinese Roxb efficiently becomes the key to the ecological control of rocky desertification by P. sinese Roxb. In this study, the ecological agriculture development model of "P. sinese Roxb-rocky desertification control-edible mushrooms" was studied, and the effect of cultivating Pleurotus eryngii with P. sinese Roxb in rocky desertification land was analyzed. Moreover, an outlook for the application of P. sinese Roxb in rocky desertification areas of Guizhou was given.

Physio-ecological adaptability and service function in karst rocky desertification control of Premna puberula

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.

Ecological compensation for desertification control:A review

Desertification control is a crucial way to enhancing the ecological conditions of arid and semi-arid regions, and maintaining sustainable development globally. Designing and improving an ecological compensation mechanism for desertification control has great significance related to achieving balance amongst the needs of different economic subjects and the assurance of a sustained and stable supply of desert ecosystem services. In this paper,(1) the theoretical bases of ecological compensation for desertification control were re-analyzed;(2) the research status and challenges of three important topics related to ecological compensation for desertification control were systemically discussed, including compensation standards, ecosystem service supply-consumption process and multi-scale effects, and resource-environment basis and policy orientation;(3) a research framework of ecological compensation for desertification control based on the process of desert ecosystem service supply–flow–consumption was proposed;(4) and finally, seven priority research issues were discussed, which aimed to support ecological compensation policy-making and ecological engineering implementation for desertification control.

Assessing the effect of desertification controlling projects and policies in northern Shaanxi Province, China by integrating remote sensing and farmer investigation data

To combat desertification, the Chinese govern- ment has launched a series of Desertification Controlling Projects and Policies over the past several decades. However, the effect of these projects and policies remains controversial due to a lack of suitable methods and data to assess them. In this paper, the authors selected the farming- pastoral region of the northern Shaanxi Province in China as a sample region and attempted to assess the effect of Desertification Controlling Projects and Policies launched after 2000 by combining remote sensing and farmer investigation data. The results showed that the combina- tion of these two complementary assessments can provide comprehensive information to support decision-making. According to the remote sensing and Net Primary Production data, the research region experienced an obvious desertification reversion between 2000 and 2010, and approximately 70% of this reversion can be explained by Desertification Controlling Projects and Policies. Farmer investigation data also indicated that these projects and policies were the dominating factor contributing to desertification reversion, and approxi- mately 70% of investigated farmers agreed with this conclusion. However, low supervision and subsidy levels were issues that limited the policy effect. Therefore, it is necessary for the government to enhance supervision, raise subsidy levels, and develop environmental protection regulations to encourage more farmers to participate in desertification control.

Nebkhas play important roles in desertification control and biodiversity protection in arid and semi-arid regions of China

Nebkhas are isolated mounds vegetated with burial-tolerant desert plants that trap windborne sediment within their canopies.Nebkhas are critical to desertification control and biodiversity protection of oases in arid and semi-arid regions of China,as they(ⅰ)trap windborne sediments and ensure oasis security;(ⅱ)as“fertile islands,”nebkhas can trap and provide a suitable micro-environment for seeds,birds,and small soil animals,and increase biodiversity;(ⅲ)increase the soil surface roughness and significantly reduce soil erosion following heavy rain.However,the establishment of sand-fixing vegetation and over-grazing significantly limits the development and accelerate the degradation of nebkhas,threatening oasis ecosystems.We provide background and recommendations for protective measures for nebkha landscapes in arid and semi-arid areas of China to aid managers in oasis protection.

Prevention and Control Mode of Desertification in China＇s State Energy Group Shendong Mining Area with Annual Coal Output of 200 Million Tons

According to the strategic goal of sustainable development,construction and management for the construction of Shendong mining area with ecological safety,the ecological restoration principle of ＂ control protects development and development promotes control＂ for desertification prevention and control was adopted,and engineering measures,plant greening measures,and enclosure management and protection measures were taken to prevent and control desertification in the mining area based on careful detailed investigation and accurate planning and design in the early period. After 32 years,the desertification ecological landscape environment of the mining area has undergone a qualitative change,and the vegetation coverage has increased from 3%-8% to above 60% after the development. The former desertification land has become a modern green energy base that has produced 200 million tons of coal every year. The construction and management mode of an ecologically safe and modernized green coal mining area built by Shendong in the desertification region of northwestern China shows that taking appropriate comprehensive ecological restoration construction technology and management measures that integrate engineering,plants and enclosure management and protection is an effective technical and management paradigm for the construction of a modernized green large-scale coal mining area in China＇s arid and semi-arid regions.

An over review of desertification in Xinjiang,Northwest China

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.

STATUS, CAUSES AND COMBATING SUGGESTIONS OF SANDY DESERTIFICATION IN QINGHAI-TIBET PLATEAU

The Qinghai-Tibet Plateau is one of the major sandy desertification regions of China. Based on the recent investigation on sandy desertification, this paper analyses the status such as the type, area, distribution and damage of sandy land desertification in the plateau. Through the analysis on the factors affecting sandy desertification in the region’s natural and socio-economic systems as well as the processes and their interrelations, it can be concluded that sandy desertification in the Qinghai-Tibet Plateau resulted from the combined actions of normal natural sand drift processes, natural sandy desertification processes caused by climatic changes and man-made sandy desertification caused by improper human activities. In addition, it also predicts the possible developmental trend including the increase in desertification area and the enhancement in desertification developmental degree with the exacerbation of the complex processes, and finally puts forward some strategic suggestions to combat sandy desertification in the coming years.

Desertification and Blown Sand Disaster in China

Approximately 331 million ha, one-third of China＇s total land, is prone to desertification processes, leading to natural disasters and economic losses. In this study, the situation, tendency, their influences and their risk governance of desertification and blown sand disaster in China were examined using satellite images, field photographs, field data and a literature review. The desiccated areas in Lop Nor and the lower Heihe River fluvial plain covered about 50,000 km2 and 40,000 km2, respectively. In Ejina, about 100 species of vegetation became extinct. The rate of wind erosion in China was between 1,000 tons/km2/year and 2,000 tons/km2/year. There were 12 sand deserts and sandy lands, occupying a total of 710,000 km2. Salinized soils occurred across 99.1 million ha. The two main sand and dust storm-prone areas in China were the Tarim Basin and its surroundings, and the Alxa Plateau and its surroundings. From 1981 to 2007, the annual average frequency of sand and dust storms varied from 1 d to 37 d with a general increase from southeast to northwest. Since 1978, China has implemented a number of ecological construction projects that have reduced desertification from 1999 to 2004 and from 2005 to 2009, and the number of dust and sand storm days from 9.3 d between 1954 and 1959 to 4.4 d between 2000 and 2007. The results could improve understanding of desertification and blown sand disasters in China and provide valuable experiences for global desertification control.

Ecological Remediation Measures for Non-point Source Pollution Based on Source-Sink Landscape Theory: A Case Study of Huanghou Basin

The growth of society and population has led to a range of water pollution issues.Among these,non-point source pollution assessment and treatment pose a particular challenge due to its formation mechanism.This has become a focal point and challenge in water pollution treatment research.The study area for this research was the Huanghou basin in Guizhou Province,southwest China.The land use type of the basin was analyzed using remote sensing technology,and water quality data was collected by distributing points throughout the basin,based on source-sink landscape theory.The distribution map of the basin’s source-sink landscape and the results of water quality data accurately and efficiently identified the areas with high risk of non-point source pollution in the western and southwestern residential and agricultural areas of the upper basin.Hence,a strategy of“increasing sinks and decreasing sources”was proposed.The strategy was implemented at both macro and micro levels to address non-point source pollution in the basin using ecological remediation techniques.The work to control karst rocky desertification should continue at a macro level.The rocky desertification area in the basin should gradually transform into grassland and forested land,while increasing the overall area of the sink landscape.Ecological restoration techniques,such as slope planting,riparian zone vegetation restoration,increasing plant abundance,and restoring aquatic plants,can effectively control non-point source pollution at the micro level.Compared to traditional control methods,this remediation strategy focuses on source and process control.It is more effective and does not require large-scale water pollution control projects,which can save a lot of environmental control funds and management costs.Therefore,it has greater research significance and application value.

A win-win technique of stabilizing sand dune and purifying paper mill black-liquor

The principle and technique were reported here to produce lignin-based sand stabilizing material （LSSM） using extracted lignin from black liquor of straw paper mills. Field tests using LSSM to stabilize and green sand dunes were started in 2002. The field experiment was carded out in August 2005 when the newly formed plant community was 3 years old. The results from the comprehensive field experiment demonstrated that unlike polyvinyl acetate or foamed asphalt commonly used for dune stabilization, LSSM was plant- friendly material and could be used in combination with seeding and planting of desert species. With the help of LSSM, the desert species （i.e., Agriophyllum squarrosum （L.） Moq. and Artemisia desertorum Spreng. etc.） could be used to form community in 2-3 yeas and to stabilize sand dune effectively. The newly formed community was sustainable under an extremely dry climate condition. The organic matter and total nitrogen in the soil increased significantly as the community were formed, while the change in P and K contents in the soil was negligible.

Effect of sand-fixing vegetation on the hydrological regulation function of sand dunes and its practical significance

Soil water content is a key controlling factor for vegetation restoration in sand dunes.The deep seepage and lateral migration of water in dunes affect the recharge process of deep soil water and groundwater in sand dune ecosystems.To determine the influence of vegetation on the hydrological regulation function of sand dunes,we examined the deep seepage and lateral migration of dune water with different vegetation coverages during the growing season in the Horqin Sandy Land,China.The results showed that the deep seepage and lateral migration of water decreased with the increase in vegetation coverage on the dunes.The accumulated deep seepage water of mobile dunes(vegetation coverage<5%)and dunes with vegetation coverage of 18.03%,27.12%,and 50.65%accounted for 56.53%,51.82%,18.98%,and 0.26%,respectively,of the rainfall in the same period.The accumulated lateral migration of water in these dunes accounted for 12.39%,6.33%,2.23%,and 7.61%of the rainfall in the same period.The direction and position of the dune slope affected the soil water deep seepage and lateral migration process.The amounts of deep seepage and lateral migration of water on the windward slope were lower than those on the leeward slope.The amounts of deep seepage and lateral migration of water showed a decreasing trend from the bottom to the middle and to the top of the dune slope.According to the above results,during the construction of sand-control projects in sandy regions,we suggest that a certain area of mobile dunes(>13.75%)should be retained as a water resource reservoir to maintain the water balance of artificial fixed dune ecosystems.These findings provide reliable evidence for the accurate assessment of water resources within the sand dune ecosystem and guide the construction of desertification control projects.

Spatial distribution of wind erosion and its driving factors in China

Based on remote sensing and geographic information system, the spatial distribution of nation-wide wind erosion is studied, and the 1∶100 000 national map of soil erosion by wind in China is made. Wind speed, soil dryness,NDVI, soil texture and the slope of land surface are the key factors to wind erosion. The relations between wind erosion and each factor are discussed. The method of principal component is used to pick up the information included in the five factors, and the wind erosion dynamic index (WEDI) is established. Its comparison with theRS/GIS derived data shows thatWEDI can reflect the potential capacity of soil erosion by wind. The dynamic process of the wind erosion is studied to reveal the distribution of the most intense wind erosion regions and the dominant factors in these regions. All these studies may greatly help the mitigation of wind erosion of soil.

Analysis on Green Development Strategy of Xinjiang Cotton

Through on-the-spot investigation and survey in Xinjiang cotton region and relevant data( containing statistical data,online information and government documents,etc.),the characteristics of water resource,wind-sand disaster,soil salinization,cotton diseases,insect pests and weeds in Xinjiang are studied. It is proposed reasons and specific programmes of green development strategy of Xinjiang cotton,and specific strategies contain ecological water supply,land desertification control,soil improvement,and ecological control of diseases,insect pests and weeds,thereby providing the support for sustainable development of Xinjiang cotton.

Spatial changes of wind erosion-caused landscapes and their relation with wind field in China

Based on the results of remote sensing investigations of the landscapes of 1995 and 2000, the national distribution of sandy desertified land and its interaction with other landscapes are classified, and five zonal types are distinguished. The data of nationally distributed 400 meteorological stations of 1999 are processed. With the GIS method, the data are spatially interpolated, and the national database of wind field concerned with wind erosion is established. In arid and semi-arid areas of China, the intensity of wind field is one of the key factors that controls the development of landscape especially in desert and its adjacent area. Different indexes are set up to describe the intensity of wind field, the method suggested by the wind erosion prediction models of RWEQ is also adopted to express the intensity of wind. The Weibull distribution is used to describe the wind field in China. Based on the analysis of the process of the wind erosion-driven landscape changes, this article proposes and discusses the control measures of wind erosion.

Water Consumption of a Six-Year-Old River Red Gum Plantation in the Southern Zagros Mountains,Iran

Water is the most important limiting factor in the development of arid environments; therefore, optimization of water use is a necessity in desert reclamation projects. Evapotranspiration of a 6-year-old river red gum （Eucalyptus camaldulensis Dehnh.） plantation, located in a sedimentation basin of an artificial recharge of the Gareh Bygone Plain groundwater system in Iran＇s southern Zagros Mountains, was studied during a 7-month period. A neutron moisture probe was used to monitor soil water changes in the root zone. Soil water depletion following rapid drainage for blocks receiving relatively high, medium and low volumes of foodwater were 809.6, 312.4, and 203.1 mm, respectively, for a 150-day period. Soil water potential during most of the study period was below -1.5 MPa. This study proves that river red gum in not a suitable species for desertification control where water conservation is of vital importance. Flood irrigation of trees on 8 Aug. 1991 provided the opportunity to throw doubt upon the claim of summer dormancy of river red gum.

Effect of Land Use and Land Cover Change on the Changes in Net Primary Productivity in Karst Areas of Southwest China:A Case Study of Huanjiang Maonan Autonomous County

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.