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Drylands are vast and face threats from climate change and human activities. Traditional reviews cannot capture interdisciplinary knowledge, but bibliometric analysis provides valuable insights. Our study conducted bibliometric research of scientific production on climate change and land degradation in drylands using remote sensing. We examined 1527 Scopus-indexed publications to identify geographic and thematic hotspots, extracting leading authors, journals, and institutions. China leads in publications, followed by the US, Germany, and Australia. The US has the highest citation count. Collaboration networks involve the US, China, and European countries. There has been an exponential increase in remote sensing of land degradation in drylands (RSLDD) publications since 2011. Key journals include "International Journal of Remote Sensing" and "Remote Sensing of Environment". The analysis highlights the growing interest in the field, driven by Australia, the US, and China. Key areas of study are vegetation dynamics and land use change. Future perspectives for this scientific field involve promoting collaboration and exploring emerging technologies for comprehensive land degradation and desertification research. [ABSTRACT FROM AUTHOR]

Karst desertification (KD) is a major ecological and environmental problem threatening human survival and development in karst areas. In order to explore the research situation and development trend of KD based on forest ecology, this paper provides a systematic literature review based on the CNKI and WoS databases, which involves search, appraisal, synthesis, and analysis. We performed a statistical and visual analysis of 2955 studies acquired between 1 January 1995 and 30 June 2023, including the time distribution of the studies, hot research trends, pivotal research clusters, literature co-citations, main publishing trends, and keyword bursts. The results show the following. (1) The literature shows a fluctuating growth trend, and the research trends are divided into accumulation, development, and expansion stages. (2) The pivotal research clusters comprised three major aspects: study area and method, driving and genetic mechanisms, and control technology and models. (3) KD research forms a China-centered research network, dominated by institutions and scholars in southwestern China. (4) Future research needs to solve a series of related scientific issues and technological needs for forest ecosystem function optimization, ecological product supply capacity enhancement, ecological product value realization, ecological industry formation, and rural revitalization in KD control. The purpose of this paper is to reveal research trends relating to KD and highlight the future direction of KD research and control. [ABSTRACT FROM AUTHOR]

Poplar (Populus sp.) plantations have been used broadly for combating desertification, urban greening, and paper and wood production in northern China. However, given the high water use by the species and the regional dry environment, the long-term sustainability of these plantations needs to be evaluated. Currently, the understanding of energy partitioning and canopy resistance to water vapor and CO2 in poplar plantations is limited, impeding an accurate assessment of their true ecosystem functions. This study examined the variability of canopy bulk resistance parameters and energy partitioning over a four-year period encompassing both dry and wet conditions in a poplar (Populus euramericana CV. "74 / 76") plantation ecosystem located in northern China. Available energy (Net radiation Rn minus Soil Heat Flux, G) partitioning to latent (LE) and sensible (H) heat was responsive to climatological drought, with LE/(Rn-G) ranging from 62% in wet years (e.g. 2007 and 2008) to 53% in dry years (e.g. 2006 and 2009), and H/(Rn-G) from 25 to 33% between wet and dry years. Correspondingly, the Bowen ratio (β=H/LE) were 0.83 and 1.57. Surface resistance (Rs) had the greatest response to drought (+43%), but the aerodynamic and climatological resistances did not change significantly (p > 0.05). Partial correlation analysis indicated that Rs was the dominant factor in controlling the Bowen ratio. Furthermore, Rs was the major factor controlling LE during the growing season, even in wet years, as indicated by the decoupling coefficient (Ω = 0.45 and 0.39 in wet and dry years, respectively), and the LE / LEeq ratio ranged from 0.81 and 0.68 in wet and dry years, respectively. In general, the dry surface conditions dominated in this poplar plantation ecosystem regardless of soil water availability suggesting that fast-growing and water use-intensive species like poplar plantations are poorly adapted for the water limited region. [ABSTRACT FROM AUTHOR]

Lanzhou City is located in the semi-arid region of northwest China, which experiences serious desertification. Moreover, the high intensity of land development, with the accelerated industrialization and urbanization, causes increasingly aggravated conflict between humans and the environment. Exploring the response of the ecological environment quality to the natural environment and anthropogenic activities is important to protect the sustainable development of urban economic construction and the environment. Based on the Google Earth Engine (GEE) platform, this paper constructed a modified Remote Sensing Ecological Index (MRSEI) model which could reflect the ecological environment quality by integrating the desertification index (DI) into the Remote Sensing Ecological index (RSEI) model. This paper explores the spatiotemporal variation in the environmental quality from 2000 to 2020 in Lanzhou, China, and analyzes the natural and anthropogenic factors affecting the environment quality in terms of temperature, precipitation, gross domestic product (GDP), land use, night lighting, and population. The results showed that the mean value of MRSEI ranged from 0.254 to 0.400. The area undergoing fast growth in ecological quality was in the northwestern part of Lanzhou, and the area of decrease was in the central part. Various factors have different degrees of influence on the ecosystem, with temperature, precipitation, and land use having a greater impact, and GDP and population having a limited impact. Precipitation and temperature showed a strong impact when interacting with other factors, demonstrating that precipitation and temperature were also key factors affecting MRSEI. Overall, climate change and the implementation of ecological restoration projects have led to an improvement in the quality of the ecological environment in Lanzhou. This study provides a reference for understanding the spatiotemporal changes in the ecological environment in semi-arid Lanzhou and is conducive to formulating proper protection strategies. [ABSTRACT FROM AUTHOR]

Southwest China is one of the three largest continuous karst clusters in the world; therefore, studies on karst rocky desertification in this area are very important. For more than 20 years' control, the decreasing area and risk of karst rocky desertification has contributed to the continuous ecological improvement. Nowadays, studies on rocky desertification mainly focus on the eight provinces in Southwest China, which have been designated as rocky desertification monitoring areas by the Chinese government. After the first phase of the comprehensive control project for karst rocky desertification in 2016, the expansion trend of rocky desertification in the southwest region was effectively curbed. Subsequent articles published tend to focus on analyzing the current situation, comprehensive management, or species adaptability of rocky desertification monitoring areas. However, the Qinba region in Shaanxi Province is located outside the monitoring area. In the process of studying the karst geological relics of the Zhenba Sanyuan Tiankeng Group, signs of rocky desertification have been found, but there still exists a research gap in the investigation and research on karst rocky desertification in this area which is one of the areas with the richest biodiversity in China, known as "ecological lung", "central water tower" and "biological gene bank". Unfortunately, this area is burdened with poverty, so the investigation and study of karst rocky desertification in the Qinba region of Shaanxi Province is of great significance to ensure green and high-quality development and ecological civilization construction. In this paper, by analyzing the current situation of karst rocky desertification in Southwest China, we summarized its harm to the ecological environment and social economy, clarify natural and human factors resulting in rocky desertification, and integrate the typical treatment experience in Southwest China. We also introduce three technical methods, including remote sensing interpretation, UAV remote sensing survey and analysis of carbonate dissolution rate, to provide a scientific basis for studies on karst rocky desertification in the Qinba region of Shaanxi Province. Study results show that the area of karst rocky desertification in the Qinba region covers 63.37 km², and the areas of severe, moderate and mild rocky desertification cover 17.97 km², 21.60 km² and 23.80 km², respectively. Based on the survey results, there are both regional differences and some similarities in distribution patterns in the areas of rocky desertification development. Specifically, the degree of rocky desertification in the limestone area is more severe than that in the dolomite area. It is also more severe in the area with developed water system than that in the arid and semi-arid area, and the more active the new structure is, the more severe the rocky desertification is. Compared to the Southwest China, the degree of karst rocky desertification in the Qinba region of Shaanxi Province is relatively light, with a smaller distribution area, mainly due to the less rainfall in the study area. The karst rocky desertification in Beiyang mountain of Zhen'an county is the most severe, with an area of 7.28 km². In the 1960s, a large-scale free-range of livestock severely damaged vegetation. The indiscriminate deforestation by humans further exacerbated the process of rocky desertification. The rocky desertification in Hailuogong village of Shanyang county is also severe, covering an area of 5.83 km², because the landform in this area is a typical peak-cluster depression, which is likely developed into rocky desertification. The contradiction between people and land needs to be solved urgently. In conclusion, more monitoring and research efforts are needed in Beiyang mountain and Hailuogong where the rocky desertification is severe. Firstly, we should clarify the causes of rocky desertification in the Qinba region and compare them with the causes in Southwest China to determine whether the rocky desertification is mainly resulted from natural factors or human factors. Secondly, we should know how to clarify the causes of karst rocky desertification in the Qinba region; for example, we can dynamically monitor the change of rock desertification by field verification, remote sensing interpretation, climate change analysis, etc. We can also calculate the contribution rate of each influence factor by geographical detector model. Thirdly, we should further study influence factors of karst dissolution rate. We can monitor physical and chemical properties of soil (soil moisture, carbon dioxide concentration, pH, organic matter content and porosity) in areas with moderate to severe rocky desertification, and analyze the relationship between dissolution rate and physical and chemical properties of soil in rocky desertification areas. Finally, in order to provide basic data for carbon neutrality research in Shaanxi, we should conduct studies on the carbon sink of rocky desertification areas in the Qinba region, with the methods such as dissolution test pieces and hydrochemical runoff. [ABSTRACT FROM AUTHOR]

Although we are in an era of enormous global commitments to ecological restoration (the UN Decade on ER; the Bonn Challenge), little attention has been paid to the importance of sustained commitment to individual restoration initiatives and few resources have been dedicated to monitoring, especially the long-term and broad-scale evaluations that would allow us to understand how basin-scale restoration can result in complex spatiotemporal patterns. Remote sensing offers a powerful tool for evaluating restoration initiatives focused on water management in arid regions, where changes in vegetation growth can be tracked visually with measures like the generalized difference vegetation index (GDVI). In this paper, we evaluate the Comprehensive Treatment Program of the Shiyang River Basin (CTSRB), a landscape restoration initiative in China's northwest, using a widely available remote sensing tool, showing how it can reveal the causes of fluctuating changes in restoration success. We focus on spatiotemporal variation, studying a time series from 2001 to 2020 using regression, trend, and stability analyses for six different divisions of the study region (the study area as a whole, the irrigated areas, the periphery of the irrigated regions, and the districts of Ba, Quanshan, and Hu) to evaluate the effects of the restoration initiative. The study period was divided into four equal-length phases based on the implementation timeline of the CTSRB, which includes one pre- and post-intervention interval and two stages of the CTSRB. We found that the CTSRB has played a positive role in the restoration of vegetation in the Minqin Basin, especially desert vegetation. However, the positive effects were not obvious in the first CTSRB period, which was characterized by a decline in vegetation growth likely caused by the strategy of "close the pumping-wells, transform the land", which reversed a greening trend caused by the unsustainable irrigation of wasteland prior to the project's initiation. During the second phase of the CTSRB, vegetation in the regions of "transform the land" gradually improved, and the growth of desert vegetation gradually improved and expanded as a result of more water flowing out of agricultural zones. The rate of vegetation recovery slowed down during the final phase of the CTSRB, and some areas even experienced a decline in the GDVI. Overall, our findings show that the CTSRB, by integrating water management and allowing for uninterrupted ecological restoration, drove complex regional changes in the GDVI, including successful restoration of desert vegetation. The spatiotemporal variable we observed underscores the importance of long-term commitment to arid land restoration initiatives and the importance of even longer-term monitoring using tools like remote sensing. [ABSTRACT FROM AUTHOR]

Land desertification is one of the serious ecological and environmental problems facing mankind today, which threatens the survival and development of human society. China is one of the countries with the most serious land desertification problems in the world. Therefore, it is of great theoretical value and practical significance to carry out accurate identification and monitoring of land desertification and its influencing factors in ecologically fragile areas of China. This is conducive to curbing land desertification and ensuring regional ecological security. Minqin County, Gansu Province, located in northwestern China, is one of the most serious areas of land desertification, which is also one of the four sandstorm sources in China. Based on ENVINet5, this paper constructs a high-precision land desertification identification method with an accuracy of 93.71%, which analyzes the trend and reasons of land desertification in this area, provides suggestions for disaster prevention in Minqin County. and provides a reference for other similar areas to make corresponding desertification control policies. [ABSTRACT FROM AUTHOR]

C, N and P are the key biogenic elements of terrestrial ecosystems, and their biogeochemical processes regulate nutrient cycling and play a key role in restoring degraded ecosystems. In this paper, the grassland ecosystem under artificial restoration measures (Dactylis glomerata (DG), Lolium perenne (LP), Lolium perenne + Trifolium repens (LT)), and the natural restoration measures (NG) in a typical karst plateau desertification control area of southwest China, were taken as the research object. The C, N, and P concentrations and the ecological stoichiometry of the plant–soil–microorganism system in grasslands under different restoration measures in the karst desertification area were explored. We established the following findings: (1) Compared with NG, the C, N and P concentrations of plants and soil in DG, LP and LT were higher, and LT was the highest. (2) The microbial biomass carbon (MBC), microbial biomass nitrogen (MBN) and microbial biomass phosphorus (MBP) concentrations in LT was also the highest. (3) The C:N ratio of plant and soil indicated that the N mineralization and nutrient release rate of DG, LP and LT were stronger than that of NG, and the plant growth of NG was most seriously limited by nitrogen. The N:P ratio in plant and soil indicated that the grassland was limited by P in the four treatments. (4) The result of correlation analysis showed that the cycling process of C, N and P in the plant–soil–microorganism system was coupled, and that the elements closely affected each other. In general, the effect of artificial restoration on a degraded ecosystem was relatively better than the natural restoration for increasing plant, soil and microbial nutrient concentrations, especially in the mixed-seed ecosystem of leguminous and gramineous forage. However, in the future, grassland management, appropriate N fertilizer or N-fixing plants and P fertilizer should be considered to improve the limitation of plant N and P, so as to realize the sustainable development of grasslands and the restoration of degraded ecosystems in the karst desertification control area. [ABSTRACT FROM AUTHOR]

Desert lakes are important wetland resources in the blown-sand area of western China and play a significant role in maintaining the regional ecological environment. However, large-scale coal mining in recent years has considerably impacted the deposition condition of several lakes. Rapid and accurate extraction of lake information based on satellite images is crucial for developing protective measures against desertification. However, the spatial resolution of these images often leads to mixed pixels near water boundaries, affecting extraction precision. Traditional pixel unmixing methods mainly obtain water coverage information in a mixed pixel, making it difficult to accurately describe the spatial distribution. In this paper, the cellular automata (CA) model was adopted in order to realize lake information extraction at a sub-pixel level. A mining area in Shenmu City, Shaanxi Province, China is selected as the research region, using the image of Sentinel-2 as the data source and the high spatial resolution UAV image as the reference. First, water coverage of mixed pixels in the Sentinel-2 image was calculated with the dimidiate pixel model and the fully constrained least squares (FCLS) method. Second, the mixed pixels were subdivided to form the cellular space at a sub-pixel level and the transition rules are constructed based on the water coverage information and spatial correlation. Lastly, the process was implemented using Python and IDL, with the ArcGIS and ENVI software being used for validation. The experiments show that the CA model can improve the sub-pixel positioning accuracy for lake bodies in mixed pixel image and improve classification accuracy. The FCLS-CA model has a higher accuracy and is able to identify most water bodies in the study area, and is therefore suitable for desert lake monitoring in mining areas. [ABSTRACT FROM AUTHOR]

Synergistically enhancing and realizing the value of grassland ecosystem services (ES) for economic activity is an important but challenging task for achieving sustainability in the karst desertification control (KDC). However, how to use grassland ES value characteristics in the KDC to make decisions on ES improvement, human well-being enhancement, and sustainable development remains unclear. In this paper, we took the contiguous region of karst desertification in Yunnan-Guangxi-Guizhou, China, a global hotspot, as the study area. Based on the valuation of the gross ecosystem product (GEP) and county economic intensity, we analyzed the structural and spatial characteristics of grassland GEP in the KDC using spatial analysis methods. We found that: (1) the grassland GEP in the KDC is mainly distributed in counties with low economic intensity (86.05% of the total number of counties) and vulnerable to losses caused by the livelihood of farmers; (2) the grassland GEP in the KDC is spatially small and scattered (the geographic concentration lies between 0.015 and 0.237), which makes it difficult to form industrial scale advantages; (3) the public product index (66.22–96.77%) and industry scale concentration (97.87–99.86%) of grassland GEP in the KDC are high, and most of the GEP is difficult to transform on the private market. Based on our findings, we proposed three corresponding recommendations for economic decision-making. The results of this study can provide a reference for economic decision-making regarding the management of grassland ES in karst areas with similar conditions and beyond. [ABSTRACT FROM AUTHOR]

The regional economy of desertification area plays a pivotal role in the land economy. Therefore, the rational development of deserticulture is of paramount significance to the economic, social, and ecological benefits of sand areas in western China. In this paper, we constructed a comprehensive evaluation index system for the development of deserticulture and the benefits of desertification land use. The entropy method was used to calculate the weight of each index, which was then used to evaluate the level of development in Ordos City from 2010 to 2017. Additionally, we analyzed the coupling relationship between these two subsystems. The results indicate a gradual increase in the input, output, and environmental evaluation value of deserticulture development, as well as the economic, social, and ecological benefits of desertification land use from 2010 to 2017 in Ordos City. Additionally, there has been an overall improvement in the comprehensive evaluation value of both systems. The level of coupling and coordinated development between deserticulture development and desertification land use benefits has been further enhanced, with a significant increase in the degree of subsystem coordination. Initially, there was serious internal and external developmental discoordination in the system, which gradually improved to an overall state of barely coordinated. [ABSTRACT FROM AUTHOR]

Soil erosion and water loss are serious problems on the rocky desertification slopes in the karst dynamic system of southwest China. The lack of soil and shortage of water restrict the ecological restoration of the regional slopes and utility of water resources. Therefore, a new slab trench capable of storing soil and water in layers on rocky desertification slopes is introduced in this paper to promote vegetation restoration. To explore the water-storing and -holding capacity of the new type of vegetated slab trench, five groups of model experiments were carried out on the vegetated slab trench under different rainfall intensities and different numbers of plants. Under rainfall and then following dry conditions, the effects of rainfall intensity and the number of plants on the water-storing and -holding capacity of vegetated slab trench models were compared and analyzed. Water-storing and -holding capacity was further explored in three groups of models with single planting or combinations of plants including water stored only in succulent root plant, only in succulent stem plant, or in mixed plants. The test results show that the new type of vegetated slab trench can effectively help to store and hold water. In the rainfall period, due to the runoff of the rainfall not being considered, the greater the rainfall intensity, the higher the water storage efficiency; the more vegetation implanted, the greater the blocking effect of the plant canopy during falling rainwater, and the more reduction is induced on the water storage efficiency of the vegetated slab trench. In the following dry period, both the succulent root plant and succulent stem plant have strong water storage capacity, but the succulent root plant has a stronger capacity for water storage. The growth status of the mixed plants was better than that of single planting, which may be due to the water complementarities between the succulent root plant and succulent stem plant in a mixed planting manner. This study is important for solving the problem of soil erosion and water loss in rocky desertification slopes, and it helps to restore the ecological environment of the area. [ABSTRACT FROM AUTHOR]

In China, backfill mining has been selected as an effective approach to realize the green mining of underground coal resources, where backfill materials are the major factor in the development of backfill mining. In order to provide a better reference for further research and development of backfill mining, the experience and research achievements are reviewed in this paper. Firstly, the backfill materials that have been successfully applied in Chinese underground backfill coal mining are divided into two categories according to whether water is used during the backfill mining operation. Then, the primary considerations of each backfill material during its preparation, transportation and activation stages are discussed and evaluated. Finally, suggestions for backfill material exploration are proposed in terms of the future backfill mining of coal resources in Western China, where there is serious surface desertification. [ABSTRACT FROM AUTHOR]

Since the early 2000s, China has carried out extensive "grain-for-green" and grazing exclusion practices to combat desertification in the desertification-prone region (DPR). However, the environmental and socioeconomic impacts of these practices remain unclear. We quantify and compare the changes in fractional vegetation cover (FVC) with economic and population data in the DPR before and after the implementation of these environmental programmes. Here we show that climatic change and CO2 fertilization are relatively strong drivers of vegetation rehabilitation from 2001-2020 in the DPR, and the declines in the direct incomes of farmers and herders caused by ecological practices exceed the subsidies provided by governments. To minimize economic hardship, enhance food security, and improve the returns on policy investments in the DPR, China needs to adapt its environmental programmes to address the potential impacts of future climate change and create positive synergies to combat desertification and improve the economy in this region. This paper shows that desertification combating practices decline incomes of farmers and herders, and China needs to adapt its ecological programmes to address the impacts of climate change and create positive synergies to combat desertification. [ABSTRACT FROM AUTHOR]

Clues of climate change on the Alashan Plateau since the last glacial period (40 ka) are important for revealing the mechanism of desertification of middle-latitude deserts in the Northern Hemisphere (NH). Studies are still rare for the understanding of the specific relationship of climate changes between the Alashan Plateau and the global. Based on a systematic and comparative analysis of the existing research in China and the international academic community, this paper reviews the environmental evolution history of the Alashan Plateau since the last glacial period from the records of paleo-environment and geomorphological characteristics in different deserts of the plateau (e.g., Badanjilin, Tenggeli, and Wulanbuhe). From about 40 ka to the end of the last glacial maximum, the climate on the plateau was wetter than it is today, and to the end of the Pleistocene, the climate was generally dry and the aeolian activities were enhanced. However, the climate was arid during the whole last glacial period in the Wulanbuhe Desert, evidently different from the overall pattern of the plateau. The Tenggeli Desert was characterized by an arid climate in the early Holocene. The most controversial events for the Alashan Plateau are the drought events in the middle Holocene in the Badanjilin Desert. The role and impact of the westerlies and the East Asian Summer Monsoon (EASM) systems on the climate change of the desert and even the whole plateau is a vexed question that brings different views in different periods. There is still a lack of definite evidence representing the events of global environmental change that occurred on the plateau during the discussed period. The distinctive morphology of dune mountains and the distribution of sand dunes are mutually indicative of the direction and energy of wind systems on the plateau. It is suggested that appropriate wind energy is the significant key to the desertification in these middle-latitude deserts on the plateau. From a global-scale review of climate change, the desertification of the modern-scale sandy desert landscapes on the Alashan Plateau is generally related to the global glacial period and the cold and dry climate during the past 40 ka. [ABSTRACT FROM AUTHOR]

Currently, the monitoring of rocky desertification(RD) is concentrated in the karst area, whereas the study in red-bed areas is rare. In this paper, we present a multi-scale classification framework for RD monitoring based on spectral-spatial features. At the pixel scale, we explored several spectral indices based on spectral statistics and separability analysis of land cover samples. The homogeneous land covers were classified by the decision rules from the selected spectral indices (such as NDIOI, NRRI and NDGI); At the patch scale, RD classes were further distinguished by spatial decision rules based on multiple neighborhood features including proximity, linear density, and buffer distance. The method was applied on an OLI image over the red-bed area of northwestern Jiangxi, south central China, and validated using ground-based observations. The experimental results of verification and comparison are satisfactory. This work demonstrates a methodological supplement to the monitoring of red bed RD. [ABSTRACT FROM AUTHOR]

(1) Background: In recent years, Hippophae rhamnoides has been used extensively to prevent desertification in China due to its nitrogen (N) fixation and sand stabilization abilities. However, as a dioecious species, few studies have focused on the sexual dimorphism of H. rhamnoides in response to sand burial, which frequently presents in desertification areas. (2) Methods: In this paper, we explored the ecophysiological responses of female and male saplings of H. rhamnoides under unburied treatment (control) and different sand burial depths (denoted as T33, T67, T90 and T133, corresponding to sand burial depths of 33, 67, 90 and 133 percent of the mean initial height of the saplings, respectively). (3) Results: Compared with unburied controls, the T33 treatment significantly promoted biomass accumulation and photosynthetic capacity, whereas T67 and T90 treatments inhibited biomass and physiological parameters of the two sexes. Deeper sand burial treatments, i.e., T90 and T133, significantly decreased the survival rates of the two sexes. Furthermore, the sex-specific responses of the two sexes of H. rhamnoides were affected by different depths of sand burial. Males had higher levels of stem starch and root sucrose and exhibited a larger increase in root nodule biomass under the T33 treatment, indicating better carbohydrate utilization and N fixation, whereas females showed lower total biomass and fewer root nodules, as well as more inhibition of photosynthetic and chlorophyll fluorescence parameters, water potential and root carbohydrates, indicating more negative effects on females than males under the T67 treatment. (4) Conclusions: We conclude that sex-related response and adaptation to sand burial depths may potentially affect the colonization, sex ratio and ecological function of the two sexes of H. rhamnoides in desertification areas. [ABSTRACT FROM AUTHOR]

Background: Desertification is one of the main obstacles to global sustainable development. Monitoring, evaluating and mastering its driving factors are very important for the prevention and control of desertification. As one of the largest deserts in China, the development of desertification in Otindag Sandy Land (OSL) resulted in the reduction in land productivity and serious ecological/environmental consequences. Although many ecological restoration projects have been carried out, the vegetation restoration of OSL and the impact mechanism of climate and human activities on desertification remain unclear. Methods: Taking OSL as the research area, this paper constructs the desertification index by using the remote sensing images and meteorological and socio-economic data, between 1986 and 2016, and analyzes the spatio-temporal evolution process and driving factors of desertification by using trend analysis and spearman rank correlation. Results: The results showed that: (1) Desertification in the OSL has fluctuated greatly during the past 30 years. Desertification recovered between 1986 and 1990, expanded and increased between 1990 and 2000, reduced between 2000 and 2004, developed rapidly between 2004 and 2007, and recovered again between 2007 and 2016; (2) The desertification of OSL is dominated by a non-significant change trend, accounting for 73.27%. In the significant change trend, the area of desertification rising trend is 20.32%, which is mainly located in the north and east, and the area of declining trend is 6.41%, which is mainly located in the southwest; (3) Desertification is the result of the superposition of climate and human activities. Climate change is the main influencing factor, followed by human activities, and the superposition effects of the two are spatio-temporal differences. Conclusions: These results shed light on the development of desertification in OSL and the relative importance and complex interrelationship between human activities and climate in regulating the process of desertification. Based on this, we suggest continuing to implement the ecological restoration policy and avoid the destruction of vegetation by large-scale animal husbandry in order to improve the situation of desertification. [ABSTRACT FROM AUTHOR]

Desertification is showing a trend of overall reversal and partial expansion in the agro-pastoral ecotone in northern China (APENC). Dune–interdune is the typical micro-topography in APENC and is the expansion area of desertification. Research on anti-desertification strategy at dune–interdune is of great significance to further anti-desertification. This paper studies the vertical differentiation of land use and ecosystem service intensities at dune–interdune in APENC. The fundamental reason of the vertical differentiation of land use and ecosystem service intensities is explored with monitoring data of soil moisture at different locations of dune–interdune. Cultivated land is mainly distributed in areas with an elevation < 241 m. Grain provisioning ecosystem service intensity (GPESI) and maize leaf provisioning ecosystem service intensity (MLPESI) show a downward trend with the increase in elevation at dune–interdune. GPESI has a tipping point at the elevation of 241 m. Forage provisioning ecosystem service intensity and sand fixation regulating ecosystem service intensity are high in areas with low or high elevations while low in the central area. Groundwater depth is the root cause for vertical differentiation of land use and ecosystem service intensities at dune–interdune. According to vertical changes of land use and ecosystem service intensities, and groundwater level, cultivated land with an elevation greater than 241 m should be stopped for cultivation to anti-desertification. The area of dune–interdune within 6 m of groundwater depth can be used as cultivated land. The conclusion has an important reference for other similar regions in the world. [ABSTRACT FROM AUTHOR]

Gully erosion is a major threat to ecosystems, potentially leading to desertification, land degradation, and crop loss. Developing viable gully erosion prevention and remediation strategies requires regular monitoring of the gullies. Nevertheless, it is highly challenging to automatically access the monitoring results of the gullies from the latest monitoring data by training historical data acquired by different sensors at different times. To this end, this paper presents a novel semi-supervised semantic segmentation with boundary-guided pseudo-label generation strategy and adaptive loss function method. This method takes full advantage of the historical data with labels and the latest monitoring data without labels to obtain the latest monitoring results of the gullies. The boundary-guided pseudo-label generation strategy (BPGS), guided by the inherent boundary maps of real geographic objects, fuses multiple evidence data to generate reliable pseudo-labels. Additionally, we propose an adaptive loss function based on centroid similarity (CSIM) to further alleviate the impact of pseudo-label noise. To verify the proposed method, two datasets for gully erosion monitoring are constructed according to the satellite data acquired in northeastern China. Extensive experiments demonstrate that the proposed method is more appropriate for automatic gully erosion monitoring than four state-of-the-art methods, including supervised methods and semi-supervised methods. [ABSTRACT FROM AUTHOR]

Since the 20th century, the resources and environment in Northeast China have changed, and it is one of the typical regions that have short-term or high-intensity environmental impacts in the world. However, due to the excessive consumption of regional resources and strong environmental pollution to the atmospheric environment, development is being greatly affected. Maintaining the natural ecological environment has become a very urgent task. This paper studies the important ecological environment problems in Northeast China from the perspective of double carbon goals. The study points out that there are ecological problems in Northeast China, such as the lack of forest resources, the aggravation of desertification, the decline of black soil quality, and the shrinkage of wetlands, which are severe urban environmental protection problems. At the same time, affected by the trend of world environmental change, policy drivers in Northeast China, and some relatively new environmental pollution problems, the natural environmental quality of Northeast China will still have a significant decline in the future. The future development of Northeast China will be based on the perspective of double carbon goals, constantly improve the ecological environment monitoring system, strengthen the research of scientific and technological system, strengthen innovation, and vigorously develop circular economy and further improve the construction of basic systems. Through a series of ecological environment governance and the coordinated development of economy and ecological environment, the dual growth of economy and ecological environment in Northeast China will be realized, and the overall revitalization of the old industrial zone in Northeast China will be realized. [ABSTRACT FROM AUTHOR]

Surface air temperature is a critical element in the surface–atmosphere interaction, energy exchange, and water cycle. Multi-source fusion reanalysis products (hereafter referred to as reanalysis) have spatiotemporal continuity and broad applicability that can provide key data support for various studies such as glacier melting, soil freeze-thaw and desertification, ecosystem, and climate change in the alpine region of the Qinghai–Tibet Plateau (QTP). Surface air temperature observations collected at 17 weather stations in the High-cold region Observation and Research Network for Land Surface Process and Environment of China (HORN) over the period of 2017–2018 are implemented to evaluate the advanced and widely used surface air temperature reanalysis datasets, which include the European Centre for Medium-Range Weather Forecasts (ECMWF) Fifth Generation Land Surface Reanalysis (ERA5L), the U.S. Global Land Data Assimilation System (GLDAS), and China Meteorological Administration Land Data Assimilation System (CLDAS). Results are as follows: (1) Evaluation results of temporal changes and spatial distribution characteristics indicate that the three reanalysis datasets are consistent with in-situ observations in the alpine region of the QTP. CLDAS is more consistent with observations and can better describe details of temperature distribution and variation than ERA5L and GLDAS. (2) For the evaluation period, CLDAS is 0.53 °C higher than the in-situ observation, while ERA5L and GLDAS are lower than the in-situ observation by −3.45 °C and −1.40 °C, respectively. (3) The accuracy of CLDAS is better than ERA5L and GLDAS under different elevations and land covers. We resampled three reanalysis datasets with a spatial resolution of 0.25° and used the two most common interpolation methods to analyze the impact of spatial resolution and different interpolation methods on the evaluation results. We found that the impact is small. In summary, the three reanalysis datasets all have certain applicability in the alpine region of the QTP, and the accuracy of CLDAS is significantly higher than ERA5L and GLDAS. The results of the present paper have important implications for the selection of reanalysis data in the studies of climate, ecosystem, and sustainable development in the QTP. [ABSTRACT FROM AUTHOR]

As an important part of the Earth's environmental system, sandy soils are particularly sensitive to changes in the climatic environment. As one of the four major desert regions in China, the MuUs desert has transformed from a desert to an oasis after more than half a century of ecological management. In this paper, we analyzed the spatial and temporal patterns of surface albedo, evapotranspiration, and fraction vegetation cover in the MuUs desert based on the Global Land Surface Satellite (GLASS) product with high spatial and temporal resolution and assessed the relationships between their variability and snow cover, air temperature, and precipitation. It is of great significance to understand the effect of desertification control and climate change after the conversion of land surface types in the MuUs region. The results show that the desertification control in the MuUs area has achieved remarkable results since 1982. The fraction vegetation coverage of the MuUs desert showed a significant increasing trend, with an interannual change rate of 1.32% each decade−1. The surface albedo of MuUs desert decreased significantly. Affected by vegetation and snow cover, it was lower in summer and higher in winter. The evapotranspiration showed a significant upward trend, higher in summer and lower in winter, which is significantly correlated with the changes in surface albedo, air temperature, and vegetation. In addition, the local-scale biophysical effects caused by vegetation change have influenced the climate of the MuUs region, manifested as the increase in precipitation and air temperature. In general, with the support of relevant policies and human construction projects, the overall ecological environment in the MuUs desert is developing in a good way. [ABSTRACT FROM AUTHOR]

Rocky desertification is one of the most critical ecological and environmental problems in areas underlain by carbonate rocks globally. Land cover and land use in the region affects large-scale ecosystem processes on a global scale, and many Earth system models rely on accurate land cover information. Therefore, it is important to evaluate current global land cover products and to understand the differences between them, and the findings of these studies can provide guidance to different researchers when using or making land cover products. Whereas there are many studies on the assessment of coarser resolution land cover products, there are few studies on the assessment of higher resolution land cover products (10 m). In order to provide guidance for users of 10 m data, this paper uses the rock deserted southwest region of China as the experimental area. We analyzed the consistency and accuracy of the FROM-GLC, ESA WorldCover 10 and ESRI products using spatial pattern consistency, absolute accuracy assessment of three validation samples, and analyzed their intrinsic relationships among classification systems, classification methods, and validation samples. The results show that (1) the overall accuracy of the FROM-GLC product is the highest, ranging from 49.47 to 62.42%; followed by the overall accuracy of the ESA product, ranging from 45.13 to 64.50%; and the overall accuracy of the ESRI product is the lowest, between 39.03 and 61.94%. (2) The consistency between FROM-GLC and ESA is higher than the consistency between other products, with an area correlation coefficient of 0.94. Analysis of the spatial consistency of the three products shows that the proportion of perfectly consistent areas is low at 44.89%, mainly in areas with low surface heterogeneity and more homogeneous cover types. (3) Across the study area, the main land cover types such as forest and water bodies were the most consistent across the three product species, while the grassland, shrubland, and bareland were lower. All products showed high accuracy in homogeneous areas, with local accuracy varied in other areas, especially at high altitudes in the central and western regions. Therefore, land cover users cannot use these products directly when conducting relevant studies in rocky desertification areas, as their use may introduce serious errors. [ABSTRACT FROM AUTHOR]

Due to the complex geographical situation in China, in this paper, the area of land desertification is 98.5% of the total land desertification area in China. Based on the measured data of GIS and remote sensing images, we will discuss the spatial and temporal distribution characteristics of land desertification in China by calculating standardized precipitation evapotranspiration index (SPEI) and normalized vegetation index and establishing the CA model. The results show the following. (1) The trend of desertification in China has decreased as a whole, and the percentage of nondesertification has increased from 36.91% in 1991 to 44.46% in 2020, an increase of 7.55%. Extremely severe desertification increased from 21.72% to 24.25%, an increase of 2.53%. (2) The drought situation in the study area gradually improved, and the change trend of SPEI decreased by 74%. (3) In recent ten years (2011–2020), the vegetation grew well gradually, and it was in the best state in 2018. The NDVI index value increased by 5.9% compared with the average value in this decade. (4) The model designed by us works very well, and the results of simulating and testing the Three Rivers Source region are very little different from the actual situation, which meets our research requirements. [ABSTRACT FROM AUTHOR]

This paper explores the relationship between vegetation in the Liangzhou Oasis in the Upper Shiyang River watershed (USRW) of west-central Gansu, China, and within-watershed precipitation, soil water storage, and oasis self-support. Oases along the base of the Qilian Mountains receive a significant portion of their water supply (over 90%) from surface and subsurface flow originating from the Qilian Mountains. Investigation of vegetation control on oasis water conditions in the USRW is based on an application of a process model of soil water hydrology. The model is used to simulate long-term soil water content (SWC) in the Liangzhou Oasis as a function of (i) monthly composites of Moderate Resolution Imaging Spectroradiometer (MODIS) images of land surface and mean air temperature, (ii) spatiotemporal calculations of monthly precipitation and relative humidity generated with the assistance of genetic algorithms (GAs), and (iii) a 80-m-resolution digital elevation model (DEM) of the area. Modeled removal of vegetation is shown to affect within-watershed precipitation and soil water storage by reducing the exchange of water vapor from the land surface to the air, increasing the air’s lifting condensation level by promoting drier air conditions, and causing the high-intensity precipitation band in the Qilian Mountains to weaken and to be displaced upward, leading to an overall reduction of water to the Liangzhou Oasis. [ABSTRACT FROM AUTHOR]

The source region of the Yellow River, located in the north-eastern edge of the Qinghai-Tibet Plateau, is an important water conservation region and ecological barrier of the Yellow River. In this paper, based on remote sensing technology, multi-period Landsat remote sensing images in the source region were taken as the main information source. With the assistance of field investigation, we monitored the spatial and temporal changes of desertification in the source region from 2000 to 2019. The results show that the area of desertification in the source region has accounted for 9.36% of the total area, of which the light desertification land is the major portion. The desertification is mainly distributed between the southern margin of Madoi Valley basin and the northern margin of Heihe Valley basin, and is distributed on the river valleys, lakesides, ancient rivers and piedmont proluvial fan, showing the form of patches, sheets and belts. The growth rate of desertification in the source region was 87.47% from 2000 to 2010. With a high growth rate, the process of desertification was represented by the rapid spread of desertification. From 2010 to 2019, the growth rate of desertification was 37.32%, which was relatively slow. But the moderate desertification land maintained a straight linear growth trend, showing an increasing trend of desertification degree. Through the analysis of the driving factors of desertification in the source region of the Yellow River, this paper argues that the special geographical location, climatic factors, rodent damages and human activities are the main causes of desertification. [ABSTRACT FROM AUTHOR]

The Yunnan–Guizhou Plateau (YGP) is a typical ecologically fragile region in southwest China. Water-erosion desertification (WED) is one of the most significant environmental and socio-economic issues on the YGP and has seriously restricted the socio-economic development of this region. However, the research on monitoring of the desertification trends in this region has been limited to long time-series Landsat imagery. The objectives of this research were to monitor the WED trends on the YGP using time-series Landsat imagery data from 1989 to 2016. In this paper, we present a multi-indicator rule-based method, which was used to map the WED on the YGP during this period. The results show that the addition of multiple indicators improved the WED classification accuracy to 90.61%. Overall, the following results were obtained by using the proposed method. (1) The slight desertification area on the YGP increased from 89,617.09 km2 in 1989 to 100,976.47 km2 in 2016 with an annual growth ratio (AGR) of 0.48%, the moderate desertification area increased from 80,276.65 km2 in 1989 to 90,768.39 km2 in 2016 with an AGR of 0.50%, and the severe desertification area increased from 8149.3 km2 in 1989 to 13,220.16 km2 in 2016 with an AGR of 2.39%. (2) The WED expansion on the YGP can be divided into three stages. Firstly, the total WED area increased slowly from 17.80×104 km2 in 1989 to 17.98×104 km2 in 2010 with an AGR of 0.05%. Then, the WED rapidly expanded from 17.98×104 km2 in 2010 to 20.28×104 km2 in 2013 with an AGR of 4.26%. Finally, the WED increased slightly from 20.28×104 km2 in 2013 to 20.50×104 km2 in 2016 with an AGR of 0.36%. The total areas of the different degrees of WED decreased in 1992, 1998, 2001, and 2004. (3) The driving factors of WED were analyzed based on the Geographically Weighted Regression (GWR) model. We found that precipitation, vegetation area, and gross domestic product have key roles in the processes of desertification reversion and development. However, the regression coefficients between WED and these factors exhibited considerable spatial variations. The regression coefficients of the key driving factors showed different spatial distributions based on the GWR model in the YGP. The research results can provide scientific reference information for the prevention and control of WED in the YGP. [ABSTRACT FROM AUTHOR]

The ongoing shifts in climate, coupled with human activities, are leading to significant land desertification; thus, understanding the long-term variations in ecosystem services as well as the driving factors has a significant value for ensuring ecological security in ecologically fragile arid regions. In this study, we used the RUSLE, RWEQ, CASA, and InVEST models to evaluate five typical ecosystem services (ESs) from 1990 to 2020 in the Gonghe Basin, including soil conservation, sand fixation, carbon sequestration, water yield, and habitat quality. Then, we analyzed the trade-offs between ESs and proposed scientific indications. Finally, we identified the driving mechanisms of ES spatiotemporal variations. The results showed that (1) the ecosystem services in the Gonghe Basin have, overall, improved over the past 30 years. Soil conservation, sand fixation, carbon sequestration, and water yield showed upward trends, while habitat quality showed a downward trend. (2) The relationships between ESs in the Gonghe Basin were characterized by strong synergies and weak trade-offs, with significant spatial heterogeneity in terms of the trade-off intensity. In addition, the implementation of ecological engineering may strengthen the intensity of the trade-offs. (3) Among all the factors (temperature, precipitation, wind speed, NDVI, land use type, slope, DEM and soil type) that affected ESs, NDVI had the greatest impact, and the explanatory power was 49%, followed by soil type. The explanatory power of the interactions between each factor was higher than that of a single factor, and the interaction between NDVI and soil type had the greatest impact. ESs increased by 12% mainly due to the implementation of ecological engineering projects and natural factors. The most suitable area for ESs was the southeastern edge of the Gonghe Basin. Our study will enrich the understanding of the mechanisms of ecosystem services in drylands and provide a scientific basis for the future implementation of ecological engineering on the Qinghai Tibet Plateau. [ABSTRACT FROM AUTHOR]

Vegetation restoration in dryland regions may be a powerful way to control desertification and promote local habitat recovery. In these artificial revegetation systems, ecosystem processes and functioning are strongly determined by nitrogen (N) availability, while soil inorganic N (SIN) is the major available N form and is absorbed as a main N source for plants. However, SIN dynamics, their influencing factors, and their relative importance to the ecosystem of these N‐limited systems are not well understood. A field investigation was conducted to examine the monthly variations in SIN and its response to planting age and vegetation type in a typical artificial sand‐fixing system in northwestern China. The SIN content in topsoil (0–20 cm) during the growing season ranged from 7.10 to 95.65 mg kg−1, with a mean value of 27.14 mg kg−1. Soil nitrate N had a dominant role in determining SIN monthly dynamics, which showed a fluctuating trend with two peak values in early July and late August. SIN showed a significant increasing trend with the planting age of sand‐fixing vegetation, and it was highest for Nitraria sphaerocarpa (55.66 ± 5.76 mg kg−1), followed by Haloxylon ammodendron (29.81 ± 3.47 mg kg−1) and interspace (11.39 ± 1.13 mg kg−1). SIN displayed a hump‐shaped relationship with air temperature (R2 = 0.96, p < 0.01) and had a maximum at 19.88°C. The change rate of SIN was positively correlated with accumulated precipitation (R2 = 0.99, p < 0.05). SIN was correlated significantly with soil organic carbon (SOC), total nitrogen (TN), and soil clay content. Our results revealed that climatic (air temperature and precipitation), abiotic (soil texture), plant (planting age and vegetation type), and nutrient‐related (SOC and TN) factors regulate SIN dynamics in artificial sand‐fixing vegetation systems. Climate was the predominant factor affecting soil ammonium N, and soil nutrients (SOC and TN) were the predominant factor affecting soil nitrate N. Therefore, these factors should be integrated into optimizing regional vegetation establishment and improving ecosystem management practices in sand‐fixing lands. [ABSTRACT FROM AUTHOR]

The arid region in the northern part of China is a bridge between China and neighbouring countries in the Silk Road Economic Belt, and the severe desertification in this region restricts its sustainable development. In this paper, MODIS data, including albedo, reflectance, normalized vegetation index, and land surface temperature, were selected in 2000, 2005, 2010, and 2015 to construct a decision tree to extract spatio‐temporal information of the desertified land in the arid area. The trend in desertification and transfer directions was analysed by the GIS method, and the dynamic characteristics of the desertification at different units (provincial administrative unit and typical sandy land) and with different topographic factors (slope and aspect) are discussed. Our conclusions include (a) desertification in the arid region in the northern part of China showed improvement overall and local deterioration. The deteriorating areas were located primarily in the western region of the Hunshandake Sandy Land, the tectonic zone of the Taklimakan Desert, and the Qaidam Basin; (b) the degree of desertification transfer occurred primarily at adjacent levels; (c) the desertified area in each province showed a different trend in fluctuation, and Maowusu Sandy Land recovered better among the 4 large sands; and (d) the desertified area was distributed primarily along 0o–3o slopes and showed a rapid decline at increased slopes. The change in the degree of desertification in each aspect largely was a general reversal, and the area of the north aspect was larger than that of other areas of aspects. This study provides some theoretical support for the control of desertification in the Silk Road Economic Belt. [ABSTRACT FROM AUTHOR]

China's Yellow River Basin (YRB) is sensitive to climate change due to its delicate ecosystem and complex geography. Water scarcity, soil erosion, and desertification are major challenges. To mitigate the YRB's ecological difficulties, climate change must be predicted. Based on the analysis of the evolution features of hydro-meteorological elements, the CMIP6 climate model dataset with Delta downscaling and the Empirical Orthogonal Function (EOF) is utilized to quantitatively explore the future variations in precipitation and temperature in the YRB. The following results are drawn: The spatial resolution of the CMIP6 climate model is less than 0.5° × 0.5° (i.e., about 55 km × 55 km), which is improved to 1 km × 1 km by the downscaling of Delta and has outstanding applicability to precipitation and temperature in the YRB. The most accurate models for monthly mean temperature are CESM2-WACCM, NorESM2-LM, and ACCESS-CM2, and for precipitation are ACCESS-ESM1-5, CESM2-WACCM, and IPSL-CM6A-LR. Between 2023 and 2100, annual precipitation increases by 6.89, 5.31, 7.02, and 10.18 mm/10a under the ssp126, ssp245, ssp370, and ssp585 climate scenarios, respectively, with considerable variability in precipitation in the YRB. The annual temperature shows a significant upward trend, and the change rates under the different climate scenarios are, respectively, 0.1 °C/10a, 0.3 °C/10a, 0.5 °C/10a, and 0.7 °C/10a. The increase is positively correlated with emission intensity. Based on the EOF analysis, temperature and precipitation mainly exhibit a consistent regional trend from 2023 to 2100, with the primary modal EOF1 of precipitation for each scenario exhibiting a clear spatial distribution in the southeast–northwest. [ABSTRACT FROM AUTHOR]

Research on endophytic fungi in desert plants, particularly the epiphytic or endophytic fungi of leaves, remains limited. In the extremely arid regions of northwest China, the ultra-xerophytic desert plant Haloxylon ammodendron harbors white fungi on its assimilating branches during autumn. The hyphae of these fungi intertwine, both internally and externally, comprising superficial, bridging, and endophytic types. The superficial hyphae attach to the surface of the assimilating branches and continuously grow and intersect, forming a thick layer of felt-like hyphae. This thick, felt-like layer of hyphae facilitates the adsorption of atmospheric water vapor on the surface of the hyphae or the assimilating branches, allowing H. ammodendron to capture atmospheric moisture, even under low humidity. Some superficial hyphae penetrate the cuticle into the epidermis, becoming bridging hyphae, which can rapidly transport water from the outside of the epidermis to the inside. The endophytic hyphae shuttle within the epidermis, achieving rapid water transfer within the epidermis of the assimilating branches. The presence of these three types of hyphae not only enables the assimilating branches of H. ammodendron to achieve rapid water absorption and transmission, but also facilitates the uptake of atmospheric water vapor under low humidity conditions. We discuss the mechanism by which the hyphae promote water absorption from the perspectives of hyphal composition, the formation of felt-like structures, and environmental conditions. We consider the presence of fungal hyphae on the surface of the H. ammodendron assimilating branches as an inevitable ecological process in arid environments. This study provides important theoretical insights into the mechanisms underlying the strong drought resistance of desert plants in extremely arid regions and offers strategies for desertification control. [ABSTRACT FROM AUTHOR]

South China Karst faces the challenge of balancing ecological conservation and regional development, a task made more intricate by the geological limitations of carbonate formations. Large‐scale conservation and restoration initiatives have mitigated rocky desertification and positioned South China Karst as a global hotspot for vegetation regrowth over the past two decades. However, challenges stemming from geological constraints and oversights in recognizing the synergies within social‐ecological systems remain. Here, we propose a social‐ecological framework that integrates the extended timescale of both historical and recent human impacts with the corresponding processes of forest evolution. The framework elucidates the enduring and continuous progression of "forest‐deforestation‐reforestation," offering applicability for optimizing ecological space across diverse social‐ecological contexts. Moreover, it serves to enhance the sustainability of reforestation efforts when faced with geological constraints. Plain Language Summary: South China is one of the most remarkable greening regions in the world in the last 20 years, but it is unknown whether the greening trend is sustainable. The soil is thin in South China Karst and carbonate rocks under the vegetation will affect water storage, thus affecting growth of vegetation. Moreover, the region is facing serious conflicts between people and land. We summarize the effectiveness of ecological restoration in the South China as well as the present social and natural challenges. Subsequently, we propose a research framework to get a comprehensive view of the vegetation changes in the past, present and future. It helps enhance the reforestation sustainability in the Karst critical zone. Key Points: Both the natural and social dimensions of rocky desertification controls in South China Karst are reviewedChallenges of a sustainable reforestation under geological constraints are revealedA social‐ecological framework designed to enhance sustainability of reforestation is proposed [ABSTRACT FROM AUTHOR]

The situation of rocky desertification in the southwestern part of China is very serious and has been included as one of three major ecological problems. In this study, using Landsat images as the data sources, we estimated the fractional vegetation coverage (FVC) in the Mengdong River Basin in the Hunan Province over the past 40 years, analyzed its spatio-temporal variation characteristics, and explored the driving mechanism (climate and anthropogenic) using the Mann–Kendall, Hurst index, and partial correlation methods. Specifically, the impact of ecological engineering on the recovery of vegetation cover in rocky desertification areas was analyzed and discussed in this study. The results demonstrate the following: (1) The changes in FVC in the study area before and after the rocky desertification management ecological project differed significantly, with a very small change in the rate of change in the mean value of FVC between 1987 and 1999 (<0.1%), while the FVC had a significant linear growth trend between 2000 and 2022 (>0.9%). (2) The Hurst index of FVC ranged from −0.233 to 2.476, with an average value of 0.864. The area with an H value greater than 0.75 accounted for 80.12%, indicating that the future trend in the vast majority of regions will develop in accordance with the current change trend. (3) The average partial correlation coefficients between FVC and precipitation and between FVC and temperature were −0.02 and 0.27, respectively, showing that FVC is more sensitive to temperature than precipitation. The combination of climate change and human activities is the main cause of FVC change. The contributions of climate change (precipitation and temperature) and human activities to FVC variation are about 30% and 70%, respectively. Ecological restoration projects have a significant positive effect on the recovery of vegetation in rocky desertification areas. The results of this study are intended to provide a scientific basis for analyzing the characteristics of vegetation restoration in existing rocky desertification areas and ecological management in future rocky desertification areas. [ABSTRACT FROM AUTHOR]

• Synergistic effects of surface and groundwater on desert riparian vegetation were analyzed. • The cautionary depth to groundwater for vegetation expansion in the lower Tarim River is 4.0–5.0 m. • Flooding by surface water (lateral water transfer coverage) acts as the main driver for the expansion of vegetation in arid areas. • A zonal ecological water transfer strategy helps to promote effective ecosystem restoration in the region. Restoring degraded ecosystems in drylands is challenging because of low precipitation and high evapotranspiration. Water availability determines the existence and spatiotemporal distribution patterns of key endangered species struggling to survive in the severely damaged desert riparian ecosystem of the lower Tarim River (LTR) in NW China. Ecological water flow restoration measures with high costs and uncertainties have been implemented since 2000. The key task for scientists is to assess the success and drawbacks of this restoration project and propose specific recommendations for stakeholders to optimize the ecological benefits of the project in a cost-effective manner. In this study, Landsat time-series data from 1990 to 2020 were used to extract vegetation index values from river corridors along the LTR and explore the spatiotemporal patterns of desert riparian forest (DRF) vegetation. Based on land use and surface water data, we extracted the interannual spatial distribution range of vegetation and surface water, and selected several sample plots to demonstrate the influence of surface water and groundwater on vegetation change trends. The study results showed the following. 1) From 1990 to 1999, the vegetation slowly degraded; from 2000 to 2012, the extent of vegetation restoration was approximately 1 km from the river; and from 2013 to 2020, the extent of vegetation restoration at the Yingsu and Karday sections increased to 4.5–6.0 km, while that at the Arghan and Yiganbujima sections remained within 1 km from the river. 2) The vegetation growth rate increased substantially and was spatially heterogeneous when the groundwater level reached 4.0–5.0 m and was influenced by surface water divergence; the average vegetation expansion rates per square km for P 1 –P 4 were 0.017 km2/a, 0.011 km2/a, 0.005 km2/a, and 0.002 km2/a, respectively. 3) Flooding by surface water was the main driver of vegetation expansion when groundwater was stable and elevations in surface vegetation area were often accompanied by the spreading of surface water. Surface water was significantly correlated with vegetation cover and normalized difference vegetation index (NDVI) (Water pixels–Vegetation cover [P 1 : R2 = 0.57, P < 0.001; P 2 : R2 = 0.45, P < 0.01]; Water pixels–NDVI [P 1 : R2 = 0.22, P < 0.05; P 2 : R2 = 0.40, P < 0.01]). The increase in surface vegetation has alleviated the desertification process in the LTR, and the survival of the poplar has been mitigated. The results of this paper can help decision makers to formulate reasonable ecological water conveyance strategies and realize sustainable management of DRF ecosystems in arid zones. [ABSTRACT FROM AUTHOR]

Desertification reversal is globally significant for the sustainable development of land resources. However, the mechanisms of desertification reversal at the level of plant community are still unclear. We hypothesized that desertification reversal has clear effects on plant community composition, plant functional types (PFTs), and other vegetation characteristics, including plant diversity and biomass, and their changes in the early stages of reversal are more dramatic than in later stages. We investigated the vegetation of four to five different stages of desertification reversal at each of seven large study sites in southwestern Mu Us Sandy Land, China. The results show that the dominant species in very severe desertification areas were replaced by perennial grasses in potential desertification areas. The importance values of annual forbs and perennial sub-shrubs decreased dramatically (from 42.59 and 32.98 to 22.13 and 5.54, respectively), whereas those of perennial grasses and perennial forbs increased prominently (from 13.26 and 2.71 to 53.94 and 11.79, respectively) with the reversal of desertification. Desertification reversal increased the complexity of plant community composition by increasing plant species in each PFT, and C3 plants replaced C4 plants to become the dominant PFT with reversal. Plant species richness and species diversity rose overall, and aboveground plant biomass significantly (p < 0.05) increased with the reversal of desertification. Most vegetation characteristics changed more strikingly in the early stages of desertification reversal than in later stages. Our results indicate that the type and composition of the plant community were dramatically affected by desertification reversal. Anthropogenic measures are more applicable to being employed in early stages than in later stages, and Amaranthaceae C4 plants are suggested to be planted in mobile dunes for the acceleration of desertification reversal. This study is useful for designing strategies of land management and ecological restoration in arid and semiarid regions. [ABSTRACT FROM AUTHOR]

Rocky desertification (RD), a natural and human-induced process of land degradation in karst areas, has become the primary ecological disaster and one of the obstacles to sustainable ecological development in southwest China. Nevertheless, the variation of soil physical and chemical properties, bacterial and fungal communities, and their relationships in RD forests remains limited. Therefore, soil samples were collected from forests under four degrees of RD (NRD, non-RD; LRD, light RD; MRD, moderate RD; and SRD, severe RD) and subjected to high-throughput sequencing of 16S rRNA and ITS1 genes. The results showed a significant reduction in bacterial richness and diversity, while fungal richness and diversity decreased markedly and then showed a balanced trend with the increase in RD degree, indicating that bacteria and fungi did not present the same dynamics in response to the process of RD. The bacterial communities were dominated by Proteobacteria, Actinobacteria, Acidobacteria, and Chloroflexi, while the fungal communities were dominated by Basidiomycota, Ascomycota, and Mortierellomycota. The PCoA and NMDS demonstrated significant differences in microbial communities in study sites, among which the fungal communities in non-RD forest and LRD forest clustered together, suggesting that fungal communities were more stable than bacteria in RD forest. The db-RDA, Mantel test, and random forest model confirmed the important role of soil BD, pH, SOC, AN, and AP in driving microbial diversity and communities. The IndVal analysis suggested that Chloroflexi, Patescibacteria, Atheliales, and Cantharellales with high indicator values were identified as potential bio-indicators for RD forests. This study could not only improve our understanding of bacterial and fungal community dynamics across RD gradients, but also could provide useful information for the further use of microorganisms as indicators to reflect the environmental changes and ecosystem status during forest RD. [ABSTRACT FROM AUTHOR]

Grassland desertification stands as an ecological concern globally. It is crucial for desertification prevention and control to comprehend the variation in area and severity of desertified grassland (DGL), clarify the intensities of conversion among DGLs of different desertification levels, and explore the spatial and temporal driving factors of desertification. In this study, a Desertification Difference Index (DDI) model was constructed based on albedo-EVI to extract desertification information. Subsequently, intensity analysis, the Geo-detector model, and correlation analysis were applied to analyze the dynamics and driving factors of desertification. The results showed the following: (1) Spatially, the DGL in Xilingol exhibited a zonal distribution. Temporally, the degree of DGL decreased, with the proportion of severely and moderately desertified areas decreasing from 51.77% in 2000 to 37.23% in 2020, while the proportion of nondesertified and healthy areas increased from 17.85% in 2000 to 37.40% in 2020; (2) Transition intensities among different desertification levels were more intense during 2000–2012, stabilizing during 2012–2020; (3) Meteorological factors and soil conditions primarily drive the spatial distribution of DDI, with evapotranspiration exhibiting the most significant influence (q-value of 0.83), while human activities dominate interannual DDI variations. This study provides insights into the conversion patterns among different desertification levels and the divergent driving forces shaping desertification in both spatial and temporal dimensions in Xilingol. [ABSTRACT FROM AUTHOR]

Karst rocky desertification occurs after vegetation deteriorates as a result of intensive land use, which leads to severe water loss and soil erosion and exposes basement rocks, creating a rocky landscape. Karst rocky desertification is found in humid areas in southwest China, the region most seriously affected by rocky desertification in the world. In order to promote ecological restoration and help peasants out of poverty, the Chinese government carried out the first phase of a rocky desertification control project from 2006 to 2015, which initially contained the expansion of rocky desertification. Currently, the Chinese government is prepared to implement the second phase of the rocky desertification control project, and therefore it is essential to summarise the lessons learned over the last 10 years of the first phase. In this paper, we analyse the driving social and economic factors behind rocky desertification, summarise the scientific research on rocky desertification in the region, and finally identify the main problems facing rocky desertification control. In addition, we put forward several policy suggestions that take into account the perspective of local peasants, scientific research, and China's economic development and urbanisation process. These suggestions include promoting the non-agriculturalization of household livelihoods, improving ecological compensation, strengthening the evaluation of rocky desertification control and dynamic monitoring, and strengthening research on key ecological function recovery technologies and supporting technologies. [ABSTRACT FROM AUTHOR]

Land desertification and sandstorms have been affecting cities worldwide on the edge of sandstorms, so humans have been seeking for ways to strengthen their defenses against wind and sand. High water retention capacity can improve human well-being in sandy areas. Several measures and cases have been already developed. To systematically find the differences between different ecosystem restoration models according to integrated benefits (e.g., ecological, economic and social benefits), this paper proposes an effective technical methodology to quantitatively identify sand control projects in a certain area. With the Southern edge of Tengger Desert-Shapotou in China as an example, this paper uses land use change and NDVI change rates to identify areas of wind and sand management. In addition, this paper uses actual evaporation (ET), soil moisture (SM), temperature vegetation dryness index (TVDI) and sand fixation service to compare the advantages and disadvantages of two typical sand management models in China according to their wind and sand control benefits, resource conservation, as well as socio-economic benefits. As indicated by the results, the straw checkboard engineering model has sustainable ecological and socio-economic benefits in water retention, cost consumption, as well as wind and sand control. Besides, the afforestation model achieves higher ecological benefits in the short term, whereas it has higher operating costs and poor sustainability, which makes this model difficult in maintaining ecological stability. On the whole, both types of sand control projects show their advantages and disadvantages in wind and sand control functions, resource recycling and socio-economic benefits. Furthermore, fast-growing afforestation combined with straw checkboards is capable of sustainably resisting wind and sand attacks and preventing land desertification. Accordingly, the finding of this paper can be referenced widely for wind and sand control. [ABSTRACT FROM AUTHOR]

Poplar (Populus sp.) plantations have been, on the one hand, broadly used in northern China for urban greening, combating desertification, as well as for paper and wood production. On the other hand, such plantations have been questioned occasionally for their possible negative impacts on water availability due to the higher water-use nature of poplar trees compared with other tree species in water-limited dryland regions. To further understand the acclimation of poplar species to semiarid environments and to evaluate the potential impacts of these plantations on the broader context of the region's water supply, we examine the variability of bulk resistance parameters and energy partitioning in a poplar (Populus euramericana cv. "74/76") plantation located in northern China over a 4-year period, encompassing both dry and wet conditions. The partitioning of available energy to latent heat flux (LE) decreased from 0.62 to 0.53 under mediated meteorological drought by irrigation applications. A concomitant increase in sensible heat flux (H) resulted in the increase of a Bowen ratio from 0.83 to 1.57. Partial correlation analysis indicated that surface resistance (Rs) normalized by leaf area index (LAI; Rs :LAI) increased by 50 % under drought conditions and was the dominant factor controlling the Bowen ratio. Furthermore, Rs was the main factor controlling LE during the growing season, even in wet years, as indicated by the decoupling coefficient (Ω = 0.45 and 0.39 in wet and dry years, respectively). Rs was also a major regulator of the LE = LEeq ratio, which decreased from 0.81 in wet years to 0.68 in dry years. All physiological and bioclimatological metrics indicated that the water demands of the poplar plantation were greater than the amount available through precipitation, highlighting the poor match of a water-intensive species like poplar for this water-limited region. [ABSTRACT FROM AUTHOR]

With global climate change, changes in vegetation phenology have become increasingly evident. Horqin Sandy Land is located near the eastern part of the West Liaohe River. It is the largest sandy land in China and its ecological environment is fragile. Investigating the changes in vegetation phenology in these sandy areas and determining the relationship between vegetation phenology and meteorological factors are of great importance for predicting the impacts of future climate change and understanding the response mechanisms of ecosystems. In this study, we used the time series of the Normalized Difference Vegetation Index (NDVI) from 2000 to 2021 and extracted the vegetation phenology in the Horqin Sandy Land using high-order curve fitting methods, including the start date of the growing season (SOS), the end date of the growing season (EOS), and the length of the growing season (LOS). We analyzed their temporal variation and used partial correlation analysis to determine their relationship with meteorological factors (temperature and precipitation). In addition, we compared the phenology and microclimate of forest and grassland within the study area. In the Horqin Sandy Land, the vegetation SOS was concentrated between the 115th and 150th day, the EOS was concentrated between the 260th and 305th day, and the LOS ranged from 125 to 190 days. Over the past 22 years, the SOS, EOS, and LOS of vegetation in the Horqin Sandy Land showed trends of delay, shift, and extension, with rates of change of 0.82 d/10a, 5.82 d/10a, and 5.00 d/10a, respectively. The start date of the growing season in the Horqin Sandy Land was mainly influenced by precipitation in April of the current year, while the end date was mainly influenced by precipitation in August of the current year. Overall, the SOS in the forested areas of the Horqin Sandy Land was slightly later than in the grasslands, but the EOS in the forested areas was significantly later than in the grasslands, resulting in a longer LOS in the forests. In addition, annual precipitation and the rate of precipitation increase were higher in the forested areas than in the grasslands, but soil temperature was higher in the grasslands than in the forests. Vegetation phenology in the Horqin Sandy Land has undergone significant changes, mainly manifested in the delayed end date of the growing season, the extended length of the growing season, and the differences between forest and grassland. This indicates that climate change has indeed affected phenological changes and provides a theoretical basis for subsequent ecological restoration and desertification prevention efforts in the region. [ABSTRACT FROM AUTHOR]

Desert farmland provides food for desert areas, but water is the main limiting factor of this region, thus desert farmland has an extremely fragile ecological environment. This study investigated the temporal and spatial variations of vegetation NDVI (Normalized Difference Vegetation Index) in the Ulan Buh Desert, China, from 1990 to 2022, using long-term Landsat satellite data obtained from the Google Earth Engine platform and local statistical data. The results showed that from 1990 to 2022, the NDVI exhibited relatively small fluctuations and a steady increase. Furthermore, the study analyzed the impact of climate factors, namely precipitation and temperature, on NDVI, and collected the groundwater lever changes under irrigation and farmland development. The results demonstrated a positive correlation between NDVI and both precipitation and temperature from 1990 to 2006. The study area experienced an overall trend of increasing humidity. Specifically, from 1990 to 2006, significant positive correlations with precipitation and temperature were observed in 4.4% and 5.5% of the region, respectively. From 2007 to 2022, significant positive correlations were observed in 5.4% and 72.8% of the region for precipitation and temperature, respectively. These findings suggest that temperature has become increasingly influential on vegetation NDVI, while the impact of precipitation remains relatively stable. Moreover, the study assessed the impact of human activities on vegetation NDVI. The results revealed that from 1990 to 2006, human activities contributed to 43.1% of the promotion of local vegetation NDVI, which increased to 90.9% from 2007 to 2022. This study provides valuable insights into the dynamics of vegetation in the Ulan Buh Desert and its response to climatic changes and human activities. The findings highlight the significance of climate conditions and human interventions in shaping the vegetation dynamics in the region, offering essential information for ecological restoration and conservation efforts. [ABSTRACT FROM AUTHOR]

Natural ecosystems are changing more quickly because of human activities, the type and intensity of which are directly correlated with vegetation greenness. To effectively determine how human activities affect trends in vegetation under climate change, we must differentiate between various types of human activities. The GTWR model can study the spatiotemporal non-stationary relationship between the NDVI trend and climate change. The GTWR model was incorporated into multiple climate variables and improved residual analysis to quantify the contributions of climate change and human activities on vegetation change trends in the Hexi region during different periods. This study divides human activities into four groups based on land use change: urbanization, agricultural expansion, desertification, and ecological restoration to further investigate their contribution to vegetation greenness change. The results showed that in 56.9% of the significant vegetation greening trends between 1982 and 2015, climate factors contributed only 7.4%, while human factors contributed a significant 22.7%. Since the ecological restoration project implemented in 2000, the expansion intensity of ecological restoration and urbanization increased significantly, followed by agricultural expansion and desertification. For the considerable greening trends in the Hexi region, the ecological restoration project contributed 26.7%, while agricultural expansion and urbanization contributed 17.5% and 4.6%, respectively. This study aims to provide new insights for more accurate simulation and evaluation of the interaction effects of climate change and human socio-economic development on vegetation growth. [ABSTRACT FROM AUTHOR]

The first successful sand-control was achieved in the Mu Us Desert by local people in the 1950–1960s, and their experience and approach have been extended to the whole Ordos and Northern China since then. The objective of this paper is to assess comprehensively the effectiveness of sand-control in 15 counties in and around Mu Us using multitemporal satellite images and socioeconomic data. After atmospheric correction, Landsat TM and OLI images were harnessed for land cover classification based on the ground-truth data and for derivation of the GDVI (generalized difference vegetation index) to extract the biophysical changes of the managed desert and desertification. Climatic, socioeconomic, environmental and spatial factors were selected for coupling analysis by multiple linear and logistic regression models to reveal the driving forces of desertification and their spatial determinants. The results show that from 1991 to 2020, 8712 km2 or 63% of the desert has been converted into pastures and shrublands with a greenness increase of 0.3509 in GDVI; the effectiveness of sand-control is favored by the rational agropastoral activities and policies; though desertification occurs locally, it is associated with both climatic and socioeconomic factors, such as wind speed, precipitation, water availability, distance to roads and animal husbandry. [ABSTRACT FROM AUTHOR]

To overcome the shortcoming of existing studies, this paper put forward a statistical vegetation-climate relationship model with integrated temporal and spatial characteristics. Based on this model, we quantitatively discriminated on the grid scale the relative role of climate change and human activities in the desertification dynamics from 1986 to 2000 in Yulin region. Yulin region's desertification development occurred mainly in the southern hilly and gully area and its reverse in the northwest sand and marsh area. This spatial pattern was especially evident and has never changed thoroughly. From the first time section (1986-1990) to the second (1991-1995), the desertification was developing as a whole, and either in the desertification development district or in the reverse district human activities' role was always occupying an overwhelmingly dominant position (they were 98.7% and 101.4%, respectively), the role of climate change was extremely slight. From the second time section (1991-1995) to the third (1996-2000), the desertification process was reaching a state of stability, in the desertification development district the role of climate change was nearly equivalent to that of human activities (they were 46.2% and 53.8% separately), and yet in the desertification reverse district, the role of human activities came up to 119.0%, the role of climate change amounted to −19.0%. In addition, the relative role of climate change and human activities possessed great spatial heterogeneity. The above conclusion rather coincides with the qualitative analysis in many literatures, which indicates that this method has certain rationality and can be utilized as a reference for the monitoring and studying of desertification in other areas. [ABSTRACT FROM AUTHOR]

This paper investigates the sandy desertification change between 1986 and 2000 in the western Jilin province, North China. Land use and land cover data were obtained from Landsat TM data by using a supervised classification approach. We summarized the total area of desertified land by each county, as well as the area for each of the four categories of desertified land. The changes of different types of land use and land cover between 1986 and 2000 were calculated and analyzed. Taking Tongyu and Qianan as examples, both human and natural driving forces of the sandy desertification were analyzed. Our analyses indicate that the material sources and windy, warm and dry climate are the immanent causes of potential land desertification, while the irrational human activities, such as deforestation, reclaiming and grazing in the grassland, are the external causes of potential land desertification. However, rational human activities, such as planting trees and restoring grassland can reverse the land desertification process. Furthermore, the countermeasures and suggestions for the sustainable development in ecotone between agriculture and animal husbandry in North China are put forward. [ABSTRACT FROM AUTHOR]

A comparison of structure and pattern of the soil seed bank was made between active and stabilized sand dunes in northeastern Inner Mongolia, China. The objective of this paper was to determine the significance of seed bank in vegetation restoration of sand dunes. The results showed that (1) average seed density decreased from stabilized sand dune to interdune lowland of stabilized sand dune, to interdune lowland of active sand dune, and to active sand dune; (2) horizontally, along the transect from interdune lowland to ecotone and to sand dune top, a ‘V’ shaped pattern was presented in the active dune system, and a reverse ‘V’ shaped pattern in the stabilized sand dune system; (3) vertically, the proportion (accounting for the total seeds) of seeds found in 0–20 mm soil profile decreased from stabilized sand dune to interdune lowland of stabilized sand dune, to interdune lowland of active sand dune, and to active sand dune. The same order was also found in 20–50 mm and 50–100 mm soil profiles; (4) the Sokal and Sneath similarity indices in the species-composition between soil seed bank and above-ground vegetation were ranked as: the stabilized sand dune (24%) > the interdune lowland of active sand dune (21%) > the interdune lowland of stabilized sand dune (18%) > the active sand dune (5%); and (5) vegetation restoration of active sand dunes depends on the dispersal of seeds from nearby plant communities on the interdune lowlands. Much effort must be made to preserve the lowlands, as lowlands are the most important seed reservoir in the active sand dune field. [ABSTRACT FROM AUTHOR]

Oasification and desertification are two essential processes of land use and cover (LULC) change in arid regions. Compared to desertification, which is widely regarded as the most severe global ecological issue, the importance of oasification has not received universal recognition. However, neglecting oasification can lead to detrimental outcomes to the effectiveness of ecological governance by affecting the comprehensiveness of environmental policies proposed only based on desertification. Therefore, this study incorporates oasification into the examination of desertification by analyzing land use data for five representative periods spanning from 1980 to 2020, as well as socioeconomic and environmental data from 2000 to 2010. The aim is to evaluate the spatial and temporal dynamics of oasification and desertification in the Manas River Basin and identify the underlying factors driving these processes. The findings indicated that (1) the general trend of oasification and desertification exhibited the expansion of oases and the retreat of deserts. Specifically, the oasification area showed a "decrease-increase-decrease" pattern over time, while the desertification area consistently decreased. (2) In terms of spatial distribution, oasification and desertification displayed a transition from scattered and disordered patterns to an overall more organized pattern, with the hotspot area of desertification shifting from Shawan County to Manas County over time. (3) Population density, average land GDP, soil type and annual precipitation significantly influenced the degree of oasification, with driving force q-values above 0.4, which were the key factors driving oasification. Population density and average land GDP significantly affected the degree of desertification, with driving force q-values above 0.35, which were the key factors driving desertification. The driving force of all factors increased significantly after the interaction, and socioeconomic factors influenced oasification and desertification more than other factors. The study's findings aim to provide a scientific basis for land resource use, ecological governance and sustainable development in the Manas River basin. [ABSTRACT FROM AUTHOR]