Main Land Types Research Articles

Predicting future impacts of climate and land use change on streamflow in the middle reaches of China's Yellow River

With increasing temperatures, changing weather patterns and ongoing development, it is becoming increasingly important to clarify the evolution mechanism of future regional streamflow processes and their controlling factors. In this study, an integrated framework for watershed streamflow prediction based on a Global Climate Model (GCM), the Patch-generating Land Use Simulation model (PLUS), and the Soil and Water Assessment Tool (SWAT) was proposed in the middle Yellow River. The results indicate that, compared with the baseline period (1989–2018), levels of precipitation and maximum and minimum temperatures are expected to increase in the next 30 years, resulting in a warmer and wetter regional climate. Under various climate scenarios, the annual streamflow is projected to increase by 49.2–115.1%. The acreage of various land types may have tended to be saturated, and the main land types such as cropland, forest and grassland have little change (−6.6%-0.6%), so the impact on streamflow will be correspondingly reduced. Under various land use scenarios, the annual streamflow is projected to increase by 5.0%–7.3%. The annual average streamflow trends under the combined climate and land use scenarios are consistent with the climate change scenarios, while the mean values corresponding to the combined scenarios are higher than those of the single scenario. Findings show that climate change is the main driver influencing streamflow, with a contribution of 86.3%–95.1%. This study deepens understanding of the change pattern and influence mechanism of the streamflow process, which can provide a scientific basis for the development and refinement of regional ecological construction plans.

Combining ecosystem service value and landscape ecological risk to subdivide the riparian buffer zone of the Weihe River in Shaanxi

Riparian buffer zones are transitional and ecological intersections between land and water. These areas play a major role in advancing ecosystem protection and restoration. Here, we investigated the spatial and temporal evolution of land use, ecosystem service value (ESV), and landscape ecological risk (LER) in riparian buffer zones between 1990 and 2020 using the Shaanxi section of the Weihe River as a case study using a GIS grid, the unit-area-equivalent-factor method, the landscape ecological risk index, and the natural breakpoint method. We also established four ecological zones using standardized Z-scores. The predominant land categories in the study area comprised cultivated, construction, and grassland, which together accounted for more than 80 % of the total area. The construction land demonstrated the most significant increase of 4,062.33 hm2 area, and cultivated land showed most significant decrease of 13,048.56 hm2 area, between 1990 and 2020. Next, study-site ESV increased from 28.30 × 108 CNY in 1990 to 28.94 × 108 CNY in 2020, reflecting 2.26 % growth. High-value areas were principally bodies of water and primarily situated along the Weihe River, extending from west to east along the main channel. The LER of the study area was dominated by the lowest ecological risk, low ecological risk, and medium ecological risk classes, which collectively accounted for more than 70 % of the total area. The main land types in the areas with high ecological risk were forest land and cultivated land. The study area’s LER demonstrated a decreasing trend from 1990 to 2020, and the area with the lowest ecological risk and low ecological risk zones increased by 9.97 %. The riparian buffer zone was divided into ecological restoration, reconstruction, conservation, and protection zones based on two factors, namely, ESV and LER. The most dominant of these was the ecological reconstruction zone, which showed a 13.75 % decrease in area share between 1990 and 2020. The ecological restoration zone occupied the smallest area with the largest increase of 56.63 % during this period. In conclusion, this study contributes to ecological zoning and management of the riparian buffer zone along the main channel of the Weihe River. Appropriate zoning is integral to protecting this valuable ecosystem and achieving sustainable development of surrounding human communities.

Land Use Optimization and Carbon Reserve Assessment in the Shiyang River Basin

Studying the response relationship and spatial distribution characteristics of carbon reserve and land use change and predicting the change trend of carbon reserve caused by the change of land use type in the future can provide some reference for watershed policy formulation, land use structure adjustment, and the realization of the "two-carbon" goal. Based on the land use data from 2000, 2010, and 2020, the InVEST model was used to calculate carbon reserves and analyze the change characteristics and to simulate the land use change and its impact on carbon reserves in natural development, urban development, and ecological protection in 2030 with the help of the PLUS model. The study found that ① the main land types in the Shiyang River Basin from 2000 to 2020 were cultivated land, grassland, and unused land. The area of cultivated land, water area, and construction land in the Shiyang River Basin showed a significant increasing trend, and the construction land area increased the most. ② In the natural development scenario of 2030, cultivated land, water area, and construction all increased by 6.15%, 9.56%, and 29.9%, respectively. In the urban development scenario, the area of construction land increased the most. Compared with that in the other two scenarios, the area of forest land and grassland increased in the ecological protection scenarios. ③ The carbon reserves of the Shiyang River Basin from 2000 to 2020 showed a steady increase, with an overall increase of 0.035×108 t. The increased carbon reserves were mainly due to the increase in cultivated land area. ④ In 2030, the carbon reserves of the Shiyang River Basin showed an increasing trend in all three scenarios. The carbon reserves in the three scenarios were 5.65×108, 5.64×108,and 5.73×108 t, respectively, with the largest increase in carbon reserves in the ecological conservation scenario, mainly due to the increase in grassland and woodland. The results showed that the expansion of construction land was the main cause of the loss of carbon reserves. If effective ecological protection measures are taken, the carbon reserves in the Shiyang River Basin will be improved, and the problem of the loss of carbon reserves caused by economic development can be solved.

Analysis and Forecast of Land Use Based on Patch-generating Land Usage Simulation (PLUS) Model: A Case of Shaanxi Province in China

China has witnessed a substantial number of land-use type shifts and broken land-use distribution patterns as a result of massive irrational exploitation, which has led to problems like a significant loss of environmental habitability and declining ecosystem functioning. Investigating the origins and mechanisms of land-use change is essential. The results show that earlier land-use models, which also lacked simulation studies and projections of land-use changes in Shaanxi Province over a 20-year timeframe, find it difficult to integrate quantitative and spatial pattern forecasts. This paper uses the patch-generating land usage simulation (PLUS) model to assess Shaanxi Province's land use patterns between 2000 and 2020 and predict land usage for the year 2025.Farmland, woodlands, and grassland are the three main land types that make up most of the Shaanxi Province's total area. Forests make up most of the land that will be transferred between 2000 and 2020, while agriculture makes up most of the land that will be transferred. Most of the elements influencing the spread of all land use types were rainfall and Normalized Difference Vegetation Index (NDVI). The central and southern regions of Shaanxi province will primarily experience changes in land use by 2025.This research offering a resource for Shaanxi Province's science of land use structure and efficient land resource allocation.

Assessment and prediction of carbon storage based on land use/land cover dynamics in the coastal area of Shandong Province

Changes in land use and land cover (LULC) promote regional carbon storage capacity or trigger carbon depletion, which in turn exhibited significant impact on global climate change. Understanding the impacts of LULC on changes of carbon storage in coastal areas plays a critical role in the conservation of regional ecosystems and sustainable socio-economic development. The present study acted the coastal area of Shandong Province as an example to analyze the relationship between LULC and carbon storage combined with the Integrated Valuation of Ecosystem Services and Tradeoffs (InVEST) and Patch-generating Land Use Simulation (PLUS) model. We further predicted the variation of carbon storage through the change of LULC types under three scenarios in 2030. Our results showed that cropland (which decreased by 9.41%) and built-up land (which increased by 7.66%) underwent the most significant changes over the past 20 years, while forest, grassland, wetland, water and bare land underwent less changes. As the dominant land type, cropland was also the most important carbon pool with medium carbon storage. Areas with high carbon storage were distributed in the mountains and hills, where the main land types were grassland and forest. In addition, wetland located in the Yellow River Delta also stores large amounts of carbon. Accordingly, areas with low carbon storage were widely distributed in built-up land of urban metropolitan regions. We pinpointed that the carbon storage in the coastal area of Shandong Province lost 47.96×106Mg due to the increasing of built-up land and the decreasing of cropland and forest, while ecological protection measures would effectively enhance regional carbon storage. Specifically, the regional carbon storage could be increased by 6.64×106Mg when the conversion of cropland, forest and grassland into built-up land was reduced by 20% and the conversion of wetland and water into built-up land was reduced by 30% (under the ecological priority scenario (EP)). We believe the present study could be a valid reference for administrators to develop policies in more reasonable planning of land use and urban development to achieve carbon peaking and carbon neutrality (“Dual Carbon” goals).

Impact of Land Use Change on the Spatial and Temporal Evolution of Ecosystem Service Values in South China Karst Areas

Resource depletion, land-use change, and population growth triggered by the industrial revolution represent serious issues shared globally that have altered the structure, processes, and functions of ecosystems and had significant impacts on human well-being and survival security. This paper assesses changes in ecosystem service values (ESVs) in karst areas based on the perspective of land-use change. Guizhou province, which is typical of the South China Karst (SCK) ecologically fragile areas, was taken as a research subject. The past, current, and future spatial-temporal evolution of karst ESVs were assessed, using equivalence factors and CA-Markov modelling methods. The results show that: (1) from 1980 to 2040, arable land, woodland, and grassland occupy the main land types in the study area; at the same time, the water and built-up areas show a steady growth trend, with dramatic land use shifts occurring in the western, middle, and northern parts. (2) The overall ESVs increased by US$ 31.12 million during the study period, showing a temporal change trend of first decreasing and then increasing; forest land, grassland, and arable land area shift are the main factors of ESVs change; soil conservation, biodiversity conservation, and gas regulation functions are enhanced and play a vital role in the single ESVs increase; ESVs show a basin-type spatial distribution pattern. (3) The sensitivity index is <1, the ESV is inelastic to the VC factor adjustment, and the results are true and valid. This paper found that using quantitative methods to predict land use change of the South China Karst can provide accurate assessment of the differences in supply and demand for natural and social ecosystem services (ES) in a region, clarifying the trade-offs and synergies of ecosystem service functions, contributing to the achievement of sustainable development, and providing a practical reference for global land landscape optimization and land resource planners.

Interpreting regional ecological security from perspective of ecological networks: a case study in Ningxia Hui Autonomous Region, China

The rapid economic development and intense human activities have seriously restricted the sustainable development of ecology and the maintenance of ecosystem services. Ecological network can effectively connect fragmented habitats and is an important way to couple landscape structure, ecological process, and function. This study proposes a multimodel coupling framework to explore the ecological security status of Ningxia Hui Autonomous Region (NHAR) under different development scenarios from the perspective of ecological networks. The conclusions are as follows: (1) From 2000 to 2030, grassland and arable land were the main land types of NHAR. Grassland is the main expansion land type under the ecological land protection (ELP) scenario, while construction land is the main expansion land type in two other scenarios. (2) The main gather and change of the ecological sources occurred in the central region, and the ecological expansion should develop from the middle to the south. (3) The average area of ecological sources under BAU and RED scenarios is smaller than that under ELP scenario, and more ecological corridors are needed to connect. (4) The centrality of the ecological sources under the BAU scenario is generally high, but the ecological sources under ELP and RED scenarios have undergone spatial migration. In addition, the urbanization trend of NHAR is different under different scenarios, and more attention should be paid to the maintenance and protection of ecological networks in typical areas. This study can provide important reference for NHAR's ecological space planning and ecological protection policy formulation.

Coastal land use change and evaluation of ecosystem services value enhancement under the background of Yangtze River protection: Taking Jiangyin coastal areas as an example

Evaluating the ecosystem service value is an important step to promote the sustainable development and the construction of ecological civilization of the Yangtze River Economic Belt, the related research is already very rich. However, they neglect the evaluation of coastal areas and lack the deeper thinking of ecological value. To improve these deficiencies, this study takes the coastal area of Jiangyin as the study area, constructs the evaluation method system of ecosystem service value based on the land use data in 2016 and 2020, explores the temporal and spatial variation characteristics of land use and ecosystem service value in the study area, and analyzes reasons for these changes. The results show that: (1) Cultivated land is the main land type in the coastal area, with an area change rate of -15.89%, forest land increases rapidly, with a growth rate of 281.62%, followed by water area with a growth rate of 55.98%, garden land decreases the most, with a decrease rate of 86.36%, followed by construction land of 62.19%. Land use mainly presents the characteristics of changes from construction land to other land, construction land and green space, and cultivated land to cultivated land, water area and forest land. (2) The net increase of ecosystem service value in the coastal area is 483 million, with a growth rate of 137.27%. Among them, the value of forest land accounts for the largest proportion, with a net increase of 264 million yuan and a growth rate of 109.54%. In terms of single function, flood regulation and storage accounts for the main ecosystem service value, reaching more than 65%, with a net increase of 394 million yuan. (3) In terms of spatial distribution, the ecosystem service value of water conservation, flood regulation and storage has a spatial distribution characteristic of being high in the east and low in the west, while the distribution of ecosystem service value of wind prevention and sand fixation is both high and low in the west. In addition, this study further explores the response mechanism of ecological value to the protection measures along the river and the transformation path of ecosystem service value, which provides a new path for the study of government-led evaluation of ecological protection effects in important coastal areas and ecologically sustainable development with regional multi-subject participation.

Land Use Dynamic Changes in an Arid Inland River Basin Based on Multi-Scenario Simulation

The Tarim River Basin is the largest inland river basin in China. It is located in an extremely arid region, where agriculture and animal husbandry are the main development industries. The recent rapid rise in population and land demand has intensified the competition for urban land use, making the water body ecosystem increasingly fragile. In light of these issues, it is important to comprehensively grasp regional land structure changes, improve the degree of land use, and reasonably allocate water resources to achieve the sustainable development of both the social economy and the ecological environment. This study uses the CA-Markov model, the PLUS model and the gray prediction model to simulate and validate land use/cover change (LUCC) in the Tarim River Basin, based on remote sensing data. The aim of this research is to discern the dynamic LUCC patterns and predict the evolution of future spatial and temporal patterns of land use. The study results show that grassland and barren land are currently the main land types in the Tarim River Basin. Furthermore, the significant expansion of cropland area and reduction in barren land area are the main characteristics of the changes during the study period (1992–2020), when about 1.60% of grassland and 1.36% of barren land converted to cropland. Over the next 10 years, we anticipate that land-use types in the basin will be dominated by changes in grassland and barren land, with an increasing trend in land area other than for cropland and barren land. Grassland will add 31,241.96 km2, mainly in the Dina River and the lower parts of the Weigan-Kuqu, Kashgar, Kriya, and Qarqan rivers, while barren land will decline 2.77%, with significant decreases in the middle and lower reaches of the Tarim River Basin. The findings of this study will provide a solid scientific basis for future land resource planning.

The response of ecosystem service value to land use change in the middle and lower Yellow River: A case study of the Henan section

The Henan section of the middle and lower Yellow River (HMLYR) is a crucial economic zone and ecological barrier in the Central Plains. Rapid urbanization in these areas has greatly exacerbated land use change (LUC), which is now seriously threatening the ecosystem. However, the existing research lacks any spatio-temporal analyses method of the LUC impact on ecosystem service value (ESV), which is not conducive to precise regulation and sustainable development of land resources. We attempted to make up for this shortcoming by superimposing the ESV change hot spots map onto the land use change Tupu and by constructing an evaluation model to show the effect of LUC on ESV from a spatial dimension. Our results showed that (1) cultivated land was the main land type in the HMLYR. The transformation of cultivated land to construction land had the widest range and the largest area. (2) Between 2000 and 2018, the ESV decreased by 9.774 billion CNY and the ESV spatial distribution was consistent with the topography. Forestland was the major ecological land type, while the ecosystem services types were mainly support services and regulation services in the HMLYR. (3) Construction and cultivated land changes had the greatest impact on ESV. Conversion of land types into water bodies and forestland formed ESV hot spot areas around the Yellow River, while the transition of other land types to construction land and the transition of grassland, forest land, water bodies to cultivated land formed ESV cold spots in the main urban areas. (4) The sensitivity index of all land use types was less than 1, indicating that ecological value coefficient (VC) had little influence on ESV. Decision-makers should recognize the important impact of LUC on ESV and take measures to restructure land use, especially to develop ecological lands. This will advance the multifaceted sustainable development in the Yellow River basin.

Ecological Impacts of Land Use Change in the Arid Tarim River Basin of China

Land use/cover change has become an indispensable part of global eco-environmental change research. The Tarim River Basin is the largest inland river basin in China. It is also one of the most ecologically fragile areas in the country, with greening and desertification processes coexisting. This paper analyzes the evolution of land-use/cover change in the Tarim River Basin over the past 30 years based on remote sensing data. The research also explores the contribution of conversion between different land types to the ecological environment by selecting methods, such as transfer matrix and ecological contribution rate. Results indicate that grassland and barren land are the main land types in the region, accounting for 72.46% and 18.87% of the basin area, respectively. From 1990 to 2019, cropland area increased from 33,585.89 km2 to 52,436.40 km2, an increase of 56.13%, while barren land areas decreased from 781,380.57 km2 to 760,783.29 km2. Most of the land-use conversion was grassland to other land types and other land types to barren land. Since 1990, the conversion of barren land to grassland and cropland in the basin has led to ecological improvement, whereas the conversion of grassland to cropland has caused deterioration, but with a generally improving trend. It is anticipated that, over the next decade, changes in land types will involve increases in grassland and woodland area, decreases in barren land and cropland, and an overall improvement in the ecological environment in the watershed. Since agriculture and animal husbandry are the main industries in the Tarim River Basin and the land-use structure is dominated by cropland and grassland, several key measures should be implemented. These include improving land use, rationalizing the use of water and soil resources, slowing down the expansion of cropland, and alleviating the contradiction between humans and land, with the ultimate aim of achieving sustainable development of the social economy and ecological environment.

Scenario simulation of ecological risk based on land use/cover change – A case study of the Jinghe county, China

The Jinghe County of the Ebinur Lake Basin was chosen as the study area. Based on Landsat TM / OLI images obtained in 2007 and 2017, this paper attempts to use CLUE-S model to predict LUCC under three different scenarios (Natural Development scenario, Farmland Protection scenario, Water Resources Protection scenarios) in 2027. Landscape indices and ecological risk index were calculated and spatially interpolated for the whole region, and the results of ecological risk could be divided into five different zones: extremely low, low, moderate, high and extremely high. They were carried out for assessing the spatial–temporal changes in ecological risk for each landscape pattern. The results show that: (1) Among the three scenarios designed in this paper, the spatial distribution of LUCC in the Water Resource Protection scenario has the most obvious changes, followed by the Farmland Protection scenario and the Natural Development scenario becomes the third. In the water resources protection scenario, the scale of the desert decreases, but the forest and grass part increases, which is conducive to ecological improvement. (2) the distribution area of high ecological risk areas was the largest of three different scenarios, especially the farmland protection scenario. The area of low-risk level is the largest under the water conservation scenario. The ecological risk of LUCC under the water resources protection scenario is lower, which is better for ecological environment. (3) Water bodies mainly concentrate upon low ecological risk degree, accounting for approximately 62.8%, 82.2%, and 73.1% of low ecological risk; Farmland mainly lies in the low-risk areas, accounting for 59.1%, 63.5% and 68.8% of the lower ecological risk levels; In 2027, the unused land and other land types are the main land types of the higher ecological risk areas under three different scenarios, whose proportions are 67.40%, 68.24% and 65.90%, respectively.

Spatial and temporal variations of land use and vegetation cover in Southwest China from 2000 to 2015.

Southwestern China is an important ecologically resource area and ecologically fragile area in China, which plays an important role in the national project of "Clear Waters and Green Mountains". Based on land use data set with a 1 km spatial resolution and combined with land use transfer matrix, we analyzed the characteristics and driving forces of land use change in Southwest China from 2000 to 2015. Based on the MODIS remote sensing index, we calculated the vegetation coverage in Southwest China using the dimidiate pixel model, and analyzed the changes of the normalized vegetation index (NDVI) and vegetation coverage. Results showed that the main land types were woodland, cropland and grassland. The built-up land area increased by 5874 km2(55.8%), the cropland area decreased by 6211 km2, and grassland decreased by 2099 km2. From 2000 to 2015, the area that had been changed to built-up land was the largest, mainly from cropland (contributed 68.2%), woodland (contributed 19.2%) and grassland (contributed 13.1%). The transformed areas were mostly close to urban area. The area and rate for the transformation of cropland were 7079 km2 and 2.2% respectively, accounting for 46.0% of all the transferred out areas. Most of the woodland were transformed from grassland (61.8%), mainly distributed in central and southern Guizhou and western Yunnan. Both NDVI and vegetation coverage were significantly increased, indicating that the whole region was greening. NDVI of both natural vegetation and cropland increased significantly, while the NDVI of areas with expanded build-up land decreased. Therefore, natural vegetation and cropland dominated the vegetation change in this region. Results of the resi-dual analysis showed that both climate change and human activities contributed significantly to the greening trend.

Study on the impact of coastal land use change on environment based on remote sensing data

The coastal zone is the bridge between the ocean and the mainland, the junction of the two ecosystems, the focus of the economic development of coastal cities and the gathering place of ports. Remote sensing technology uses the detector to receive the electromagnetic wave from the target object. After processing the information, it can distinguish the attributes of the target object. It is widely used in marine development, aerospace understanding, resource exploration and other fields.In this paper, the coastal zone of Shangyu Economic Development Zone on the south coast of Hangzhou Bay is taken as the research area. Using multi-source remote sensing data, information extraction, change monitoring and analysis are carried out from the perspective of marine and land ecosystems, and the impact of coastal development on the coastal zone is discussed. The main conclusions are as follows: (a) Using visual interpretation method, it is found that the coastline of the study area changes obviously, and the decrease trend is below the total coastline length; Fractal dimension index is used to characterize the natural condition of coastline. The total coastline length, natural coastline and artificial coastline all increase, which means that the amount of beach sediment deposition and the degree of artificial intervention have increased in this stage. (b) The object-oriented method is used to extract the land use classification of the coastal zone in the study area. Cultivated land is the main land type in the study area, and the impervious surface is the fastest growing. The degree of artificial development of the whole study area is gradually increasing, and the coastal beach area is greatly reduced, and the impervious surface area is greatly increased. Wetland and impervious surface are the two most dramatic changes in the study period. Wetland is mainly transformed into other surface features, while impervious surface is mainly transformed into other surface features.

Sustainable land use in the trans-provincial marginal areas in China

Because of the influence of administrative jurisdiction, land use in the boundary area of administrative jurisdiction has its particularity. Studying the spatial-temporal change pattern of land use in this region is helpful to optimize the land use pattern, improve and protect the ecological environment quality, and is of great significance to ensure the coordinated development of population, resources and environment. Based on TM satellite remote sensing and four years (1980, 1995, 2000 and 2010) image data, the land use/cover information in the trans-provincial marginal zone of China is extracted. The spatial-temporal characteristics of land use/cover change in the study area in the past 30 years are revealed using land-use temporal-spatial change index, dynamics of land-use change, comprehensive index of land-use level, change in land-use degree, rate of change in land-use and GIS spatial analysis techniques. The future 30 years development trend is predicted by Markov model method. (1) The land use in the interior provincial fringe area of China is mainly trans-provincial marginal zone. Here are dominated by forestland, grassland, and unused land. The most obvious changes are an increase in land for an increase construction land and a reduction of unused land, and there are differences in different regions. Forestland is the main land type in Northeast China. Forestland, cultivated land and grassland are important land types in southeastern China. However, grassland type is seen as unused land and woodland in Qinghai-Tibet area. Unutilized land is the main land type in Northwest China, showing a situation of increasing first and then decreasing. (2) Influenced by environmental conditions and social factors such as population growth, economic development and regional development policies, the land use types in 1980–1995 and 1995–2010 show obvious spatial differentiation characteristics in different zones. (3)From 1980 to 2010, the land use types in the study area have undergone complex transformation. The reduced area of cultivated land, woodland, grassland and water area is larger than the newly increased area, while the reduced area of construction land and unused land is smaller than the newly increased area. (4) By 2030, the increase of construction land area will have a positive effect on the economic and social development of the region. The increase of forestland area will further improve the ecological environment here.

Assessing the influence of land use on groundwater pollution based on coefficient of variation weight method: a case study of Shuangliao City.

In this study, the quality of groundwater was tested in 95 sampling wells in Shuangliao City. Based on the results, the coefficient of variation method was used to calculate the comprehensively evaluated value F, and the grade of groundwater quality, in accordance with the actual scenario in the study area, was classified according to the results of the evaluation. The spatial distribution of groundwater quality types in the study area was classified. In addition, the influence of human activity on each groundwater subsystem was assessed. Combined with the land use types in the study area, the Circle model was used to extract the land use types in the circular buffer zone with a radius of 500 m, and the Kendall rank correlation test was used to analyze the influence of the land use types on the spatial distribution of groundwater pollution. Based on the coefficient of variation, the groundwater quality standard was divided into four sections considering the actual scenario: ≤ 0.92 (I), 0.92~≤ 1.75 (II), 1.75~≤ 2.40 (III), and > 2.40 (IV). Water from class II was considered the main type for groundwater quality. NO3-, TFe, and Mn were deemed the main indexes of groundwater pollution. Further, land use type was found to have a great influence on the spatial distribution of groundwater pollution; specifically, dry land, paddy field, areas with dense traffic, and residential areas are the main land types that affect the groundwater environment.

Evaluating the Effects of Grain for Green policy through the landscape change: A Case Study in Gannan region, China

Gannan region, an important ecological barrier in the Gan Jiang River basin, is a typical southern mountain-hill area in Jiangxi Province, China, and its ecological protection is of great significance. In this study, using data of 5-year intervals from 2000 to 2015, the landscape change in the Gannan region was investigated through the application of remote sensing, geographic information technology, and spatial statistical methods. The results show that (1) The landscape pattern of Gannan region tends to be fragmented and decentralized, the landscape shape tends to be complex, and the human interference becomes more difficult. (2) Forest is the main land type in the Gannan region and decreased over the 15 years of investigation from 3094200 ha to 3068200 ha. (3) The area of farmland was rising before 2010, and then drops rapidly. Grassland shows the opposite trend to farmland, which shows the effectiveness of the Grain for Green policy. This study provides a theoretical basis and a decision support mechanism for the rational layout and protection of ecological land in Gannan region. The results could lead to improved ecological barrier functions of southern hilly region.

Spatio-Temporal Variation of Land-Use Intensity from a Multi-Perspective—Taking the Middle and Lower Reaches of Shule River Basin in China as an Example

The long-term human activities could influence land use/cover change and sustainability. As the global climate changes, humans are using more land resources to develop economy and create material wealth, which causes a tremendous influence on the structure of natural resources, ecology, and environment. Interference from human activities has facilitated land utilization and land coverage change, resulting in changes in land-use intensity. Land-use intensity can indicate the degree of the interference of human activities on lands, and is an important indicator of the sustainability of land use. Taking the middle and lower reaches of Shule River Basin as study region, this paper used “land-use degree (LUD)” and “human activity intensity (HAI)” models for land-use intensity, and analyzed the spatio-temporal variation of land-use intensity in this region from a multi-perspective. The results were as follows: (1) From 1987 to 2015, the land use structure in the study region changed little. Natural land was always the main land type, followed by semi-natural land and then artificial land. (2) The LUD in the study region increased by 35.36 over the 29 years. It increased the most rapidly from 1996 to 2007, and after 2007, it still increased, but more slowly. A spatial distribution pattern of “low land-use degree in east and west regions and high land-use degree in middle region” changed to “high land-use degree in east and middle regions and low land-use degree in west region”. (3) The human activity intensity of artificial lands (HAI-AL) in the study region decreased from 1987 to 1996, and then increased from 1996 to 2015. The human activity intensity of semi-artificial lands (HAL-SAL) in the study region increased over the 29 years, and more rapidly after 1996. (4) 1996–2007 was a transition period for the land-use intensity in the study region. This was related to the implementation of the socio-economy, policies such as “Integrated Development of Agricultural Irrigation and Immigrant Settlement in Shule River Basin (1996–2006)”, and technologies.

Soil Moisture Estimation by SAR in Alpine Fields Using Gaussian Process Regressor Trained by Model Simulations

In this paper, we address the problem of retrieving soil moisture over a grassland alpine area from Synthetic Aperture Radar (SAR) data using a statistical algorithm trained by simulations of a physical model. A time series of C-band VV-polarized Wide Swath images acquired by Envisat Advanced SAR (ASAR) in the snow-free periods of 2010 and 2011 was simulated using a discrete radiative transfer model (RTM). The test area was located in the Mazia valley, South Tyrol (Italy), where the main land types are meadows and pastures. Soil moisture was collected from five meteorological stations, two of which situated in meadows and the rest in pastures. The smallest and the highest RMSEs of the RTM simulations were 0.78 dB and 1.91 dB, respectively. After backscattering simulation, the top soil moisture was estimated using Gaussian Process Regression (GPR). GPR was trained with the backscatter model simulations (including terrain features) for 2010, and then used to predict moisture from radar observations acquired in 2011. The relative importance of different input features was also assessed. The RMSE of the predicted soil moisture for the largest training data set (including aspect as a terrain feature) was 5.6% Vol. and the corresponding correlation coefficient was 0.84.

Range of soil and climate characteristics appropriate for Pistacia atlantica forest development and rehabilitation (case study: Fars province, Iran)

Abstract Investigation of ranges of soil and climate characteristics appropriate for the tolerant species: Pistacia atlantica subsp. mutica according to field study was the main objective of this research. This study was carried out based on random sampling across 20×20 km wild pistachio forests of Fars province (Iran). Results showed that mountainous and hilly lands are the main land types that pistachio species have evolved on. Statistical analysis of physical and chemical soil characteristics based on principal component analysis (PCA) method showed that wide ranges in soil characteristics, even up to about 40% differentiation in some measured properties, did not restricts this subspecies natural growth. The main growth limiting factors were shallow soil depth and light soil texture that decreased storage capacity of soil moisture, necessary for wild pistachios survival during drought and long dry periods. Climatic elements were analysed through the same approach and showed that temperature, precipitation and wind with overall variability of 85.9% were the most effectual factors. Pistacia atlantica subsp. mutica is one of the species refractory to various soil conditions and adapted to weak soils for the establishment and rehabilitation of forests in semi-arid regions.