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The regions near the Tropic of Cancer are a latitudinal geographical zone with typical climatic, topographic, and human landscape features. It is necessary to explore the region's net primary productivity (NPP) dynamics as it combines complex topography, various vegetation types, and intense human activities. The study sets the transect near the Tropic of Cancer (TCT) and uses the Carnegie–Ames–Stanford (CASA) model to estimate the NPP from 2000 to 2020. After using the RESTREND method, the paper calculates and compares the relative contributions of climate variability and anthropogenic activities to NPP changes. Finally, the geographical detector (Geodetector) model is applied to evaluate how anthropogenic and natural factors affect spatial distribution patterns and NPP changes. The results indicated that the average annual NPP is 820.39 gC·m−2·yr−1 during the 21 years. In addition, when the NPP varies, it increases over the entire study area, with a slope of 4.81 gC·m−2·yr−1, particularly in the western region. Across the entire research area, 63.39% and 77.44% of the total pixels positively contribute to climate variability and human activities in NPP, with a contribution of 0.90 and 3.91 gC·m−2·yr−1, respectively. Within the western, central, and eastern regions, anthropogenic activities have a stronger impact on NPP than climate variability, particularly pronounced in the eastern region. Furthermore, vegetation cover is the dominant factor in the spatial patterns and NPP trends across the TCT and the three regions. In contrast, climate factors are shown to be less influential in NPP distribution than in the western region. The results also demonstrated that the effect of population density and the GDP on NPP gradually rises. Two-factor interaction is much larger than any individual factor, with the dominant interaction factor being vegetation cover with climatic factors. Lastly, the findings revealed that anthropogenic activities positively promote NPP accumulation across the TCT, thus highlighting the importance of human activity-led ecological restoration and ecological protection measures that contribute to regional carbon sequestration and carbon balance. [ABSTRACT FROM AUTHOR]

The key to simulating soil erosion is to calculate the vegetation cover (C) factor. Methods that apply remote sensing to calculate the C factor at a regional scale cannot directly use the C factor formula. That is because the C factor formula is obtained by experiments, and needs the coverage ratio data of croplands, woodlands, and grasslands at a standard plot scale. In this paper, we present a C factor conversion method from a standard plot to a km-sized grid based on large sample theory and multi-scale remote sensing. The results show that: (1) Compared with the existing C factor formula, our method is based on the coverage ratio of croplands, woodlands, and grasslands on a km-sized grid, and takes the C factor formula obtained from the standard plot experiment and applies it to a regional scale. This method improves the applicability of the C factor formula, and can satisfy the need to simulate soil erosion in large areas; (2) The vegetation coverage obtained by remote sensing interpretation is significantly consistent (paired samples t-test, t = −0.03, df = 0.12, 2-tail significance p < 0.05) and significantly correlated with the measured vegetation coverage; (3) The C factor of the study area is smaller in the middle, southern, and northern regions, and larger in the eastern and western regions. The main reason for that is the distribution of woodlands, the Hunshandake and Horqin sandy lands, and the valleys affected by human activities; (4) The method presented in this paper is more meticulous than the C factor method based on the vegetation index, improves the applicability of the C factor formula, and can be used to simulate soil erosion on a large scale and provide strong support for regional soil and water conservation planning. [ABSTRACT FROM AUTHOR]

Dexing City is an important mining city in China, abounding in copper ore, lead ore, zinc ore, and other metal resources, and there are two large open-pit mines in its territory, Dexing Copper Mine and Yinshan Mine. The two open-pit mines have been expanding their mining production scale since 2005, with frequent mining activities; and the expansion of the pits and the discharge of solid waste will undoubtedly increase the land use and cause the destruction of vegetation. Therefore, we plan to visualize the change in vegetation cover in Dexing City from 2005 to 2020 and the expansion of the two open-pit mines by calculating changes of the Fractional Vegetation Cover (FVC) in the mining area using remote sensing technology. In this study, we calculated the FVC of Dexing City in 2005, 2010, 2015 and 2020 using data from NASA Landsat Database via ENVI image analysis software, plotted the FVC reclassified maps via ArcGIS, and conducted field investigations in the mining areas of Dexing City. In this way, we can visualize the spatial and temporal changes of vegetation cover in Dexing City from 2005 to 2020, and appreciate the situation of mining expansion and its solid waste discharge in Dexing City. The results of this study showed that the vegetation cover of Dexing City remained stable from 2005 to 2020, as the expansion of mining scale and mine pits was accompanied by active environmental management and land reclamation, setting a positive example for other mining cities. • The change in FVC from 2005 to 2020 was used to visualize the impact of mining expansion in Dexing City, China. • The paper presented Dexing City as an example of a mining city that has achieved "healthy" development. • This paper described the environmental hazards associated with open-pit mining. [ABSTRACT FROM AUTHOR]

[Objective】 In this paper, the vegetation coverage of the research area for the period 2000 - 2017 was calculated by using the veg¬ etation index product (MODIS13QI) with spatial resolution of 250 meters and 16 days synthesis.【Method】 The spatial and temporal charac¬teristics of vegetation cover in the northern foothills of the central part of Tianshan, China were studied by using differential analysis in the past 18 years, and the annual and quarterly vegetation cover area was evaluated using the quantitative evaluation model of change trend.【Re- suit】 The results showed that the spatial characteristics of vegetation coverage in the northern foot of the central Tianshan Mountains gradually increased from the north to the middle to the south % The intensity of spatial changes in vegetation growth was gradually reduced fromsummer to autumn to spring. In the quantitative evaluation of annual dynamic changes in vegetation coverage, the degree of degradation was: summer spring > autumn % the annual degraded area accounted for 0. 27 % of tlie total area% The stable area of -0. 1 -0. 1 was： spring > au¬tumn > summer, annual stable area covered 84.46 % of tlie whole area% The improvement areas greater than 0. 1 were： summer > autumn spring, and the annual improvement area accounts for 15 . 27 % of the entire area. The change of the non-significant area was as follows: spring > summer > autumn, and the annual non-significant vegetation area was 64.39 % % the apparent increase trend was： summer autumn > spring, and the annual increase in area accounts for 29 . 13 %. 【Conclusion 】Through quantitative evaluation of the temporal and spatial changes of vegetation cover， the 3 value and the corresponding degree of vegetation change are defined. The seasonal vegetation cover area decreases from strong to weak and appears as ： spring > autumn > summer % The investigation of annual and quarterly vegetation dynamic changes in the study area provides a certain theoretical basis and data support for vegetation and ecological environmental protection in the northem foot of tlie central Tianshan mountains [ABSTRACT FROM AUTHOR]

The objective of this study was to map and discriminate variations of vegetation net primary production (NPP) from the effects of precipitation variability and thereby identify the effects of grazing on NPP variations in the Xilingol Grassland. Satellite-based simulations of NPP collected over 14-year period and residuals method were used to normalize the effects of interannual precipitation on NPP. A fixed-size moving-window method was developed in this paper to quantify the annual grazing pressure (defined as grazing pressure index, GPI) on the regional scale, using vegetation cover images from 2001 to 2014. Temporal and spatial analysis methods were conducted to show patterns and trends of GPI and NPP residuals (NPP res ), and further to examine the effects of grazing pressure changes on variations of NPP res . Our results showed 80.7% of the study area experienced increasing NPP res and 18.5% with significantly increasing trends ( p  < 0.05). 76.7% of the study area showed decreasing grazing pressure, and 11.8% of areas experienced significantly decreasing trends ( p  < 0.05), with a small patches scattered distribution pattern. The negative correlations between NPP res and GPI were found in 94.6% of the study area, and 41.9% with significant correlation ( p  < 0.05); and long-term decreasing grazing pressure had positive impacts on vegetation NPP. They indicate grazing is a main driving factor of variations in vegetation NPP other than precipitation in Xilingol Grassland. The spatial patterns and temporal trends of NPP res , grazing pressure and responses of NPP res to grazing pressure changes varied among three main grassland types. [ABSTRACT FROM AUTHOR]

[Display omitted] • The vegetation cover status of 9 provinces in the Yellow River basin was analyzed. • The water poverty status of 9 provinces in the Yellow River basin is analyzed. • There is a U-shaped relationship between vegetation cover and water poverty. • There were differences in the effects of vegetation cover on WPI components. Vegetation plays an important role in improving the water resource environment. Faced with the serious water poverty problem in various regions of China, whether vegetation restoration can further alleviate water poverty needs to be studied urgently. Taking 9 provinces in the Yellow River basin in China as an example, this paper first uses the framework of the existing water poverty index (WPI) to calculate the WPI of each province over the years from 1999 to 2019 and evaluate the water poverty status of each province. Later, the normalized difference vegetation index (NDVI) was used to analyze the vegetation restoration status of each area. Finally, using provincial panel data for the study area from 1999 to 2019, a comprehensive feasible generalized least squares (FGLS) model was used to analyze the impact of vegetation cover on water poverty. It was found that there was no pure linear relationship between vegetation cover and water poverty; instead, there was a significant U-shaped relationship. Moreover, the influence of vegetation cover on each component of the WPI has certain differences. This research advances knowledge on the relationship between vegetation cover and water poverty and provides ideas for effectively alleviating regional water poverty. [ABSTRACT FROM AUTHOR]

• Spatiotemporal variation in vegetation on the Loess Plateau was investigated. • Precipitation was the greatest driving factor. • There was a bivariate or nonlinear enhancement between all factors. • Key factors' adaptation range or type suitable for vegetation cover was identified. Vegetation, being a core component of ecosystems, is known to be influenced by natural and anthropogenic factors. Studying vegetation cover dynamics variation and its drivers is critical to understanding the interactions between vegetation and ecosystems. The Loess Plateau (LP) is located in a semi-arid and semi-humid region with severe soil erosion and fragile ecology. This paper used the annual maximum Normalized Difference Vegetation Index (NDVI ymax) and growing season mean NDVI (NDVI gsmean) as the vegetation cover indicator. The vegetation cover variation of LP from 2000 to 2020 was analyzed using Sen's slope and Mann-Kendall test. Then the influence of natural and anthropogenic factors on the driving mechanisms of spatial vegetation differentiation was explored by the Geodetector model. The results revealed that the growth trends of NDVI ymax and NDVI gsmean were 0.075/10 years and 0.038/10 years, respectively, and the areas with improved vegetation cover accounted for 92.67 % and 88.58 % of the total area. The vegetation cover of the southeastern and northern parts of the LP decreased significantly; however, the central, southwestern, and northeastern parts exhibited a remarkable improvement. Precipitation, vegetation type, soil type, temperature, and land use type were the key driving forces, ranked differently on NDVI ymax and NDVI gsmean. However, precipitation was the most critical factor both on NDVI ymax and NDVI gsmean. The interaction detection showed non-linear and mutual enhancement, with no independent factor. The findings of our study can assist in identifying the vegetation cover status of the LP, as well as the driving forces, which can provide theoretical support for the formulation of environmental conservation policies. [ABSTRACT FROM AUTHOR]

Through field investigation and comprehensive analysis, this paper classified green space system on campus of Southwest University of Science & Technology into points, lines and surfaces, and used basic theories of ecology, botany, garden aesthetics, and plant landscape assessment to analyze ornamental characteristics, seasonal changes, spatial layers and cultural connotations of its typical plant landscapes, so as to assess campus plant landscape comprehensively in the near future. [ABSTRACT FROM AUTHOR]

Taking natural grassland on the northern slope of the Qilian Mountain for example, this paper investigated and compared above-ground and bclowground biomass of grassland in multi-year enclosure (20 years), one-year enclosure, control areas (natural grazing areas). The results showed that coverage and height of the enclosure sample plots were significantly higher than that of natural grazing area (P<0.05); mean aboveground biomass of grassland: multi-year enclosure (316.58 g/m2) > one-year enclosure area (299.07 g/m2) > multi-year enclosure control area (254.39 g/m2) > one-year enclosure control area (187.37 g/m2); bclowground biomass: multi-year enclosure (2,906.90 g/m2) > one-year enclosure area (2,587.26 g/m2) > multi-year enclosure control area (2,378.93 g/m") > one-year enclosure control area (2,029.17 g/m"); mean aboveground biomass of natural grassland was 263.60 g/m2, mean belowground biomass 2,225.56 g/m2; ratio of belowground biomass to aboveground biomass varied between 6.79 and 12.90, distribution of bclowground biomass and aboveground biomass in each plot showed significant differences (P <0.05). Enclosure was favorable for improving the coverage and biomass of natural grassland plant communities in the Qilian Mountains. [ABSTRACT FROM AUTHOR]

Validation over heterogeneous areas is critical to ensuring the quality of remote sensing products. This paper focuses on the sampling methods used to validate the coarse-resolution fractional vegetation cover (FVC) product in the Heihe River Basin, where the patterns of spatial variations in and between land cover types vary significantly in the different growth stages of vegetation. A sampling method, called the mean of surface with non-homogeneity (MSN) method, and three other sampling methods are examined with real-world data obtained in 2012. A series of 15-m-resolution fractional vegetation cover reference maps were generated using the regressions of field-measured and satellite data. The sampling methods were tested using the 15-m-resolution normalized difference vegetation index (NDVI) and land cover maps over a complete period of vegetation growth. Two scenes were selected to represent the situations in which sampling locations were sparsely and densely distributed. The results show that the FVCs estimated using the MSN method have errors of approximately less than 0.03 in the two selected scenes. The validation accuracy of the sampling methods varies with variations in the stratified non-homogeneity in the different growing stages of the vegetation. The MSN method, which considers both heterogeneity and autocorrelations between strata, is recommended for use in the determination of samplings prior to the design of an experimental campaign. In addition, the slight scaling bias caused by the non-linear relationship between NDVI and FVC samples is discussed. The positive or negative trend of the biases predicted using a Taylor expansion is found to be consistent with that of the real biases. [ABSTRACT FROM AUTHOR]

Differences among regions in the meteorological, surface, and vegetation cover characteristics lead to differences in sediment transport. In this paper, field data were measured above five surface types in the arid zone of northern China to analyze the vertical distribution of sediments in the near-surface transport layer (0-50 cm) and total sediment transport. We were able to express the sediment flux in this zone as an exponential function for all surface types. Sediment transport differed among the surfaces, with the greatest transport above mobile dunes, followed by cultivated land, semi-fixed dunes, fixed dunes, and a shrub community. Vegetation coverage is important for reducing wind erosion and increasing the proportion of the creep sediment transport. With increasing vegetation cover, the soil erosion decreased; the amount for the mobile dunes was 659 times that of the shrub community, and 8 times for fixed dunes. The proportion of sediment transported by creeping differed among the five surface types, with a minimum of 33% for the mobile dunes, and maximum of 44% for the shrub community. [ABSTRACT FROM AUTHOR]

As one of the most intensively eroded regions worldwide, soil erosion assessment is currently gaining further momentum in the Loess Plateau (LP), China. However, there exist very few review studies that assess soil erosion in relation to land use and land cover (LULC), climate, and ecosystem services (ESs) at multiple temporal and spatial scales in the LP. Thus, this review provides a comprehensive review of the interactions among soil erosion assessment, climate change, LULC change, and ESs at different scales. We focused on the academic literature published in the English language and analyzed the coverage of soil erosion across 109 publications. Our results highlighted three aspects: (1) studies dealing with the effects of LULC change on soil erosion are abundant. A recent surge in research interest is to explore a threshold of vegetation cover to support a sustainable eco-hydrological environment in the LP. However, the impacts of multiple stressors on soil erosion have received limited attention. (2) The short-term soil erosion assessment dominated the published studies. Cross-spatial-scale and long-term erosion assessments have received little attention. (3) 43% of reviewed papers used a field measurement method to assess soil erosion with the validation of measurement methods. 41% of reviewed papers used empirical models to assess soil erosion, but the modeling validation remains an unsolved problem. Then, three recommendations are listed as follows: (1) the combined impacts of LULC and climate change on soil erosion need to be further examined. (2) Long-term and cross-spatial-scale soil erosion assessments need to be established. (3) Soil erosion modeling accuracy on a large scale needs to be developed. • The assessment of multiple stressors on soil erosion has received limited attention. • Poor coverage of multi-spatial scale and long-term soil erosion assessment. • Large scale soil erosion modeling validation remains an unsolved problem. • A recent surge in academic interest is to explore thresholds of vegetation cover in the Loess Plateau. [ABSTRACT FROM AUTHOR]

Summary: Soil moisture is an effective water source for plant growth in the semi-arid Loess Plateau of China. Characterizing the response of deep soil moisture to land use and afforestation is important for the sustainability of vegetation restoration in this region. In this paper, the dynamics of soil moisture were quantified to evaluate the effect of land use on soil moisture at a depth of 2m. Specifically, the gravimetric soil moisture content was measured in the soil layer between 0 and 8m for five land use types in the Longtan catchment of the western Loess Plateau. The land use types included traditional farmland, native grassland, and lands converted from traditional farmland (pasture grassland, shrubland and forestland). Results indicate that the deep soil moisture content decreased more than 35% after land use conversion, and a soil moisture deficit appeared in all types of land with introduced vegetation. The introduced vegetation decreased the soil moisture content to levels lower than the reference value representing no human impact in the entire 0–8m soil profile. No significant differences appeared between different land use types and introduced vegetation covers, especially in deeper soil layers, regardless of which plant species were introduced. High planting density was found to be the main reason for the severe deficit of soil moisture. Landscape management activities such as tillage activities, micro-topography reconstruction, and fallowed farmland affected soil moisture in both shallow and deep soil layers. Tillage and micro-topography reconstruction can be used as effective countermeasures to reduce the soil moisture deficit due to their ability to increase soil moisture content. For sustainable vegetation restoration in a vulnerable semi-arid region, the plant density should be optimized with local soil moisture conditions and appropriate landscape management practices. [Copyright &y& Elsevier]

It appears that two main factors hinder the effective incorporation of ecological information derived from computer modeling in resource management at large spatial scales: (1) some models are not ecologically sound and (2) most models based on ecological principles are often too sophisticated or detailed, having complex structures and requiring a large range of input data. This paper employs a generic model based on well-established ecological principles, but with appropriate detail, to better serve decision-making in sustainable resource management. The model was used to simulate aboveground net primary productivity (ANPP), foliage projective cover (FPC), and the evaporation coefficient (k) for large arid areas in northwest China, where there has been serious desertification recently. Observation data of ANPP and FPC in the study area were used to validate the model, and the model results were in good agreement with observation data and other published data. The model was then used to simulate the evaporation coefficient, FPC, and ANPP for the study area. The simulation results indicated that except for several sites, the k parameter was lower than 0.35 × 10-2 and implied a typical arid climate in the study area. Estimated FPC of the plant community was lower than 50% at most sites, and the annual ANPP was very low-less than 1 tons · ha-1 · yr-1 at 93.8% of sites. These simulation results could serve as references for vegetation restoration and livestock husbandry management in arid areas of China. [ABSTRACT FROM AUTHOR]

Abstract: Beijing’s mountainous areas have an important ecological significance because they are ecological conservation and water source protection areas of Beijing. The impact of precipitation on the vegetation coverage of Beijing’s mountainous areas is qualitatively analyzed using multi-temporal Landsat images obtained during the last 20 years. Firstly, the influence of external factors, such as phenology and relative radiometric correction, on the normalized difference vegetation index (NDVI) are removed by the normalization of remote sensing images for different periods. Then, the vegetation coverage is calculated using the method of the dimidiate pixel model. Finally, based on that, the relationship between precipitation in different seasons and change of vegetation coverage is discussed. The results indicate that the mean vegetation coverage has the same change trends with winter and summer precipitation, but an opposite change trend with spring precipitation. The paper provides a theoretical basis and data support for further research on driving models of natural vegetation restoration in Beijing’s mountainous areas. [Copyright &y& Elsevier]

Abstract: A thawing ditch existing in permafrost region along the Qinghai–Tibet Railway is studied with their geological features, failure characteristics, ground temperatures, and influence on permafrost roadbed in this paper. The failure shows surface subsidence and horizontal slip on the shoulder. Integrated analysis from the field-monitored data show that the thawing ditch totally subsided more than 11cm from January 2008 to (month) 2010 and the average was close to 6cm a−1. The active layer on both shoulders of the thawing ditch has been slipped inward, and the max horizontal displacement in 0.5m depth was 5–6cm a−1. The warm season is the main period of the failure expanding in scale, especially from August to October. The mean annual ground temperature in shallow layer was about 0.9°C higher in the thawing ditch bottom than in the natural ground (remove about 20m) during the past two years (2008–2009). Due to the vegetation covered on the thawing ditch was destroyed, and the heat absorbed exceeds obviously heat released. The estimated result using the data in 2008 and 2009 shows that the input of heat into the permafrost below the thawing ditch was about 114,000kJ m−2 and was more than the output of 88,000kJ m−2 in twoyears. The heat absorbing starts in mid April, ends at the beginning of November, and lasts over 230days. In addition, the lateral thermal erosion of thawing ditch would influence the surrounding permafrost and damage the adjacent engineering infrastructure. The approximate calculation shows that about 90,000kJ heat was transported from thawing ditch to adjacent permafrost in 2009. Therefore, the permafrost beneath the thawing ditch has been degrading, warming, and declining in stability. [Copyright &y& Elsevier]

Abstract: Pollen concentration has been commonly used to indicate vegetation cover and moisture change. However, this practice may not always be justified in arid and semi-arid regions. This paper investigates potential problems with the approach based on modern pollen assemblages and fossil pollen data from arid and semi-arid China. The results show that pollen concentration has no direct relationship with vegetation cover and effective moisture in our study region. Pollen representation and sediment accumulation rate may have contributed to the complication. We conclude that pollen concentration cannot be used as a reliable index of effective moisture in arid and semi-arid regions. [Copyright &y& Elsevier]

Abstract: The eco-environment in the Three Gorges Reservoir Area (TGRA) in China has received much attention due to the construction of the Three Gorges Hydropower Station. Land use/land cover changes (LUCC) are a major cause of ecological environmental changes. In this paper, the spatial landscape dynamics from 1978 to 2005 in this area are monitored and recent changes are analyzed, using the Landsat TM (MSS) images of 1978, 1988, 1995, 2000 and 2005. Vegetation cover fractions for a vegetation cover analysis are retrieved from MODIS/Terra imagery from 2000 to 2006, being the period before and after the rising water level of the reservoir. Several analytical indices have been used to analyze spatial and temporal changes. Results indicate that cropland, woodland, and grassland areas reduced continuously over the past 30 years, while river and built-up area increased by 2.79% and 4.45% from 2000 to 2005, respectively. The built-up area increased at the cost of decreased cropland, woodland and grassland. The vegetation cover fraction increased slightly. We conclude that significant changes in land use/land cover have occurred in the Three Gorges Reservoir Area. The main cause is a continuous economic and urban/rural development, followed by environmental management policies after construction of the Three Gorges Dam. [Copyright &y& Elsevier]

Influencing factor analysis is required for assessing the performance of vegetation fractional coverage (VFC) models with remote sensing imagery. This paper analyses influences of the radiometric correction level (RL), vegetation index (VI) and polynomial exponential power (EP) choice on VI-VFC relationship models. A SPOT 5 HRG image of Nanjing, China was chosen, and three RLs (digital number, top of atmosphere reflectance and post atmospheric correction reflectance) were used to derive six VIs, such as normalized difference vegetation index (NDVI) and ratio vegetation index (RVI). Fifty-four models describing the VI-VFC relationship were established, and the influences of the RL, VI and EP choice on the VI-VFC models were analysed based on a statistical analysis of determination coefficients (R 2) of these models. The results showed that model robustness was jointly influenced by the three factors, so these three factors should be synthetically taken into account in VI-VFC modelling. It is recommended to establish different models between the VFC and various VIs derived from different RLs, and then to select the better ones. [ABSTRACT FROM AUTHOR]

Green vegetation plays a vital role in urban ecosystem services. Rapid urbanization often tends to induce urban vegetation cover fragmentation (UVCF) in cities and suburbs. Mapping the changes in the structure (aggregation) and abundance of urban vegetation cover helps to make improved policies for sustainable urban development. In this paper, a new distance-based landscape indicator to UVCF, Frag, was proposed first. Unlike many other landscape indicators, Frag measures UVCF by considering simultaneously both the structure and abundance of vegetation cover at local scales, and thus provides a more comprehensive perspective in understanding the spatial distribution patterns in urban greenness cover. As a case study, the urban greenness fragmentation indicated by Frag was demonstrated in Wuhan metropolitan area (WMA), China in 2015 and 2020. Support vector machine (SVM) was then designed to examine the impact on the Frag changes from the associated factors, including urbanization and terrain characteristics (elevation and slope). The Frag changes were mapped at different scales and modeled by SVM from the selected factors, which reasonably explained the Frag changes. Sensitivity analysis for the SVM model revealed that urbanization showed the most dominant factor for the Frag changes, followed by terrain elevation and slope. We conclude that Frag is an effective scale-dependent indicator to UVCF that can reflect changes in the structure and abundance of urban vegetation cover, and that modeling the impact of the associated factors on UVCF via the Frag indicator can provide essential information for urban planners. [ABSTRACT FROM AUTHOR]

Coastal morphodynamics and environmental changes have been obviously altered by global warming, sea-level fluctuations, and human activities. Palynological analysis is one of the most important tools for providing information on vegetation, climate, and environmental change, which can be relatively sensitive indicators of human activity during the Holocene. However, Holocene coastal morphodynamics and palynological evidence from the Pearl River Delta and coastal areas has not been sufficiently studied. In this paper, we carry out analyses using detailed grain-size and palynological records of pollen, spores, freshwater algae, and marine dinoflagellate cysts from Borehole QZK13 in the Pearl River Estuary (PRE), southern China. The results show information relating coastal morphodynamics, vegetation evolution, climate changes, and anthropogenic activities during the Holocene based on radiocarbon chronology. In general, the PRE experienced marine transgressive processes; sea-level and the coastline tended to migrate landward between 10,700 and 4250 cal yr BP. Meanwhile, abundant arboreal pollen (mainly Castanopsis , Quercus -evergreen, Oleaceae, and Castanea) and small amounts of non-arboreal pollen (mainly Poaceae, Cyperaceae, and Artemisia) were observed in Borehole QZK13, which suggests that subtropical evergreen broadleaved forests were distributed throughout the PRE and adjacent areas, and relatively warm and moist climatic conditions were present during the early-middle Holocene. After that, there were relatively cool and wet climatic conditions, and marine regressive processes occurred in the PRE during the Late Holocene (ca. 4250–960 cal yr BP) indicated by an abrupt increase in aquatic herbs and Dicranopteris. Moreover, we hypothesize that the Neolithic "cultural fault" in the PRE is likely related to frequent storm surges induced by extreme typhoon events that occurred ca. 3000–2700 yr BP. • Grain size, pollen, spores, freshwater algae and dinoflagellate cysts from the Pearl River Estuary were investigated. • Three major phases shown by palynological results were corresponding to the changes in vegetation and climate. • We hypothesized that the Neolithic "cultural fault" is probably related to the storm surges induced by extreme typhoon events. • Natural vegetation cover has suffered large-scale destruction by ancient humans during the Late Holocene. [ABSTRACT FROM AUTHOR]

Geo-environmental factors are believed to be major determinants of rural poverty. However, few studies have quantified the effects of these factors on rural poverty in China. In this paper, we used county-level poverty incidence data and geo-environmental factors to explore spatial patterns of the incidence of poverty using global and local spatial autocorrelation analysis and to investigate the effect of geo-environment factors on rural poverty using a geo-detector model. Our results demonstrated that there was spatial clustering of the incidence of poverty in the study area. The incidence of poverty decreased from south to north and from the east and west to the central area. The incidence of high–high poverty areas was mainly distributed in the southeast of Guizhou Province and the incidence of low–low poverty areas was distributed in the northeast. The results also demonstrated that percentage of effective irrigation on arable land, slope, elevation and vegetation cover were the dominant factors explaining the spatial pattern of poverty. Interaction analysis demonstrated that the slope non-linearly enhanced the percentage of effective irrigation on arable land. Our findings suggested that geo-environment is the fundamental control factor explaining the spatial pattern of rural poverty in China. Through analysis of the impact of the geo-environment on the spatial pattern of poverty, this study provides a reference for effectively implementing targeted alleviation of poverty. [ABSTRACT FROM AUTHOR]

• Ecological land provides wind erosion prevention service (WEPS). • From 1990 to 2015, the area of ecological land decreased while non-ecological land increased. • The effects of five second-level types of ecological land changes on WEPS were discussed. • The transformation of desert to ecological landimproved WEPS. • The improvement of second-level ecological land types with low vegetation cover improved WEPS. As an important "buffer" to slow down the expansion of desertification, ecological land can provide wind erosion prevention service (WEPS), which is closely related to regional ecological security and human well-being. Previous studies have focused on the response of WEPS to land use change, to a certain extent, would easily cause uncertainties, where the same type can be influenced by different physical and anthropogenic factors and further alter the WEPS. To solve this problem, ecological land was defined from the main function of land in this paper as a new indicator, and the impact of ecological land change on WEPS was quantitatively measured. The results indicated the following: (1) During the period 1990–2015, the net area of ecological land reduced by 16,244 km2 or 17.74%. All second-level types of ecological land experienced a decreasing trend. (2) The annual average WEPS rate in the Tarim Basin was 34.82%, which increased by 1.42% across the 25 year period. (3) The increase of WEPS was mainly attributed to the expansion of oasis and the transformation of second-level ecological land types from low vegetation coverage to high vegetation coverage. The transformation of ecological land to desert was the main reason for the deterioration in WEPS. In the period 1990–2015, the protection and effective management of ecological land improved the ecological environment and increased the surface shelter in some regions, which was conducive to the improvement in WEPS. [ABSTRACT FROM AUTHOR]

• The changes of NDVI in urbanized areas of most cities in China exhibited 'U' shapes. • More vegetation degradation was found in urbanized areas than in outer buffers. • Overall, urbanization has negative effects on vegetation for most cities of China. • The adverse effects of urbanization on vegetation gradually diminished over time. • The valid influence distance of urbanization on vegetation may be about 30–40 km. A better understanding the effects of urbanization on vegetation is vital to promoting the sustainable development of cities in China, which has also experienced the world's most remarkable urbanization during the past decades. This paper used satellite-derived night light, vegetation index, and socio-economic data to analyze spatio-temporal patterns of vegetation changes and evaluate the influence of urbanization on vegetation cover in 46 Chinese metropolises over the last four decades. To examine the effects of urbanization on vegetation and its valid distance, we proposed a new method of comparing three indicators, namely, annual average normalized difference vegetation index (NDVI), long-term trend of NDVI change and the proportion of pixels characterized by significant change in NDVI between built-up areas and its multiple buffer zones. The results showed that the effects of urbanization on vegetation have obvious spatial differences. Urbanization generally resulted in the decrease of vegetation coverage in built-up areas for most of China's central and eastern metropolises, while in Western China, usually restricted by natural conditions, the urbanization usually improved vegetation coverage. The rates of increase in NDVI were significant lower than that of the buffer zones for most cities in central and eastern China. Urbanized areas of most cities located in central and eastern China had a higher percent of vegetation pixels, representing degradation than that in the buffer zones. The opposite was true for pixels representing vegetation restoration. The changes of NDVI in the cities in Western China were basically contrary to those in central and eastern China. The impacts of urbanization on vegetation are stage-specific. With the continuous progress of urbanization level, the adverse effect of urbanization on vegetation were gradually diminished or even disappeared. Cities with higher nighttime light levels appeared to have less vegetation coverage in the early years, and negative correlations between mean NDVI and the mean digital number value have become weak in more recent years. The changes in NDVI in urbanized areas of most cities significantly followed a 'U' shape. This phenomenon may further suggest that positive effects of urbanization become more obvious over time during advanced urbanization. The spatial scope of the impacts of urbanization on vegetation was beyond the urban built-up areas, and the effect intensity appeared to attenuate as the buffer distance became further away from the urbanized area. The valid distance of impacts of urbanization on vegetation is generally about 30–40 km. [ABSTRACT FROM AUTHOR]