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Ecological environment assessment can not only provide significant references for effective solutions to regional ecological problems, but also promote the benign interaction of socio-economic-ecological development. This study selected the Heihe River Basin (HRB) as the typical area to comprehensively evaluate the ecological environment from 2010 to 2030 based on the dynamics of land system (DLS) model, which is coupled with the biological abundance index (BAI), vegetation coverage index (VCI), water density index (WDI), land degradation index (LDI), and eco-environment quality index (EQI). The results indicate that the BAI and VCI will be high in the south and east, low in the north and west in general. Under the future baseline scenario, the changes of biological abundance, vegetation coverage, and deteriorating land in the midstream and downstream regions will may seriously hinder restoration of the ecological environment. In particular, the BAI in the midstream and downstream regions will decline more rapidly, with a rate of 10.30% and 18.59%, respectively. The water area will be scattered and less abundant overall, but the WDI in the midstream, that is up to 3.86 in 2030, will be higher than that in other regions. Results also show that the regions with high EQI are mainly located in the northeast and south region. It is predicted that the ecological fragile zones in the future will mainly distribute in the midstream and downstream regions, especially in Jiayuguan City and Jinta County. The EQI will drop by 44.28% and 11.40% during 2010-2030 without external conditions intervened. In addition, Qilian Mountain, Jiuquan City, Gaotai County, Linze County, and Shandan County will also have relatively strong recovery capacities under the influence of ecological policies. All above could provide the basis for the development of future watershed ecological environment management and protection planning.

In arid regions, land development and degradation (LDD) is sustained by the undesirable land development, human production and living, and climate change. Therefore, the understanding of LDD processes and their driving mechanism in the arid or semi-arid regions is significant to guarantee the sustainable development of ecological environment. This study explored the critical LDD processes in the Heihe River Basin (HRB) during 1990-2010 with the spatio-temporal evaluation of critical land use dynamics and its land quality changing trends. Then, the driving mechanism of cultivated land development process, grassland degradation process and water resource change process were analyzed by a simultaneous equations model which took the interaction of three processes into account. The results showed that the mutual transfers of cultivated land were primarily gathered in the middle reaches from 1990 to 2010. Its area grew by 13.5% and the average dynamic degree remained at 0.61%. The transfers between grassland and cultivated land, unused land were more remarkable, which led to the decline of grassland quality and even grassland degradation. Water area maintained a dynamic balance with almost unchanged area, but its dynamic trend was initially increasing and then decreasing. However, the average degradation of land quality in the whole study area is continuously alleviated. These changes were mainly due to the interaction of the LDD processes above, as well as socio-economic and climate change. Among them，agricultural research investments could restrain the unordered expansion of cultivated land resource for a relatively short period of time. Meanwhile, the variable of whether it is the main grain producing county is the main driver of grassland and water resource degradation in this region. These conclusions will provide scientific references for ecological land restoration and land quality improvement in the HRB.

With the rising pressure due to energy consumption and costs of environmental protection and recovery, industrial transfer from the eastern to central and western areas has surged in China. However, extremely fragile ecological conditions and severe water shortage are significant hurdles for industry development in Western China. Whether the vulnerable environment can bear the pollution caused by the transferred industry from Eastern China becomes a significant issue. This study firstly estimates energy and environmental costs in different areas of China, and assesses the necessity to upgrade the industrial structure of Qinghai Province. Then the emissions of waste water, waste gas, and smoke caused by transferred industries are calculated by Input-Output Model. On the basis of the effect analysis of waste emission on environment, pollution risks of Qinghai province are assessed. The results illustrate that the costs of environmental protection and recovery in China have a gradient distribution, of which the energy efficiency is lower while environmental costs are higher in Western China. Industrial structure adjustment has different impacts on the pollution of different sectors. Although the development of machinery and equipment, hotels and catering services, and real estate, leasing, and business services has increased the emission of pollutants, it is offset by the decreasing emissions caused by other industries such as construction and metal products. Therefore, although economic development will increase environmental pollution, industrial adjustments can effectively decrease waste water and waste gas emissions to reduce the pollution risk. It should be noted that there are still tremendous challenges for industrial transfer in Qinghai Province to coordinate the environment and industry development.

This study applies the Dynamics of Land System (DLS) model to simulating the land cover under the designed scenarios and then analyzes the effects of land cover conversion on energy flux in the semiarid grassland area of China with the Weather Research and Forecasting (WRF) model. The results indicate that the grassland will show a steadily upgrowing trend under the coordinated environmental sustainability (CES) scenario. Compared to the CES scenario, the rate of increase in grassland cover is lower, while the rate of increase in urban land cover will be higher under the rapid economic growth (REG) scenario. Although the conversion from cropland to grassland will reduce the energy flux, the expansion of urban area and decreasing of forestry area will bring about more energy flux. As a whole, the energy flux of near surface will obviously not change under the CES scenario, and the climate therefore will not be possible to be influenced greatly by land cover change. The energy flux under the REG scenario is higher than that under the CES scenario. Those research conclusions can offer valuable information for the land use planning and climate change adaptation in the semiarid grassland area of China.

The land-use and land-cover change (LUCC) is the synthetic result of natural processes and human activities; it largely depends on the surface vegetation conditions, and the mutual conversion among land cover types can accelerate or alleviate the regional and global climate changes. Aiming at analyzing the regional climatic effects of the conversion from grassland to forestland, especially in the long term perspective, we carried out the comparison simulation using the Weather Research and Forecasting (WRF) Model in Fujian province, results indicated that this conversion had a significant influence on the regional climate; the annual average temperature decreased by 0.11°C and the annual average precipitation increased by 46 mm after 11.2% of the grassland was converted into the forestland in the study area from 2000 to 2008. In the future (form 2010 to 2050), the conversion from grassland to forestland is significant under two representative concentration pathways (RCPs) (RCP6 and RCP8.5); the spatial pattern of this conversion under the two scenarios is simulated by dynamic of land system (DLS); then, the regional climate effects of the conversion are simulated using WRF model.

With the water and soil conservation forests ofRobinia pseudoacaciain the Malian beach of Hongqi farm, Ji County, Shanxi province, as the research object, this study estimated the potential evapotranspiration in the open space outside the forest and at the heights of 3 m, 6 m, and 10 m in the forests with the climate data during 2011-2012 and the upgraded Penman-Monteith formula; then, this study explored the microclimate characteristics inside and outside theRobinia pseudoacaciaforest and thereafter revealed the vertical variation rules of potential evapotranspiration ofRobinia pseudoacacia. The results indicate that the air temperature, relative humidity, wind speed, and potential evapotranspiration at different heights above the ground surface showed similar changing trends, but with some variation during different periods. In addition, the weather also had impacts on the potential evapotranspiration. In April, July, and October, the change of potential evapotranspiration of theRobinia pseudoacaciaforests showed a bimodal curve in the sunny days and rainy days, while it showed a single-peak curve with quite small fluctuation in the rainy days. However, it showed a single-peak pattern even in the sunny days in January, and it showed no fluctuation in the snowy days in January.

Land Use/Land Cover change (LUCC) is a key aspect of global environmental change, which has a significant impact on climate change. In the background of increasing global warming resulting from greenhouse effect, to understand the impact of land use change on climate change is necessary and meaningful. In this study, we choose China as the study area and explore the possible land use change trends based on the AgLU module and ERB module of global change assessment model (GCAM model and Global Change Assessment Model). We design three scenarios based on socioeconomic development and simulated the corresponding structure change of land use according to the three scenarios with different parameters. Then we simulate the different emission of CO2under different scenarios based on the simulation results of structure change of land use. At last, we choose the most suitable scenario that could control the emission of CO2best and obtain the relatively better land use structure change for adaption of climate change. Through this research we can provide a theoretical basis for the future land use planning to adapt to climate change.

Ecological risk assessment is of great significance to promoting the rational management effectively for the oil-polluted areas. A comprehensive evaluation method of ecological risk, including probabilistic risk assessment and regional ecological risk assessment, is developed through employing the contaminant benzo[a]pyrene as an indicator to assess ecological risk of five oil mining plots, respectively in Yellow River Delta. In this study, firstly we evaluate the ecological risk probability of five oil mining plots using overlapping area of probabilistic curves, and the results show that local ecological risk varies between the maximum 0.4 and the minimum 0.01. Then we overlay boundaries of five administrative divisions in Yellow River Delta and the spatial distribution patterns of ecosystems to generate new risk receptor plaques, and calculate the integrated value of 30 specifically classified plaques for comprehensive evaluation of ecological risk. The results, fluctuating within the range of 0.00005 and 0.25, indicate that local government should be vigilant to ecological risk of benzo[a]pyrene to some extent, although the current situation is not severe in whole.

Near surface energy budget changes have been proved to be induced by the land cover conversion through changing the surface physical properties, which can further impact the regional climate change. This study applies the DLS model to simulate the land cover under the business as usual (BAU) scenario and then analyses the seasonal and interannual variation of energy balance in the semiarid grassland area of China based on the simulated land cover with the Weather Research and Forecasting (WRF) model. The results indicate that the grassland will show a growing trend under the BAU scenario. Downward long wave radiation and downward short wave radiation will all have small-scale increase with time going by, while the surface net radiation will decrease from 2030 to 2050. However, there is obvious seasonal variation. Summer has the highest downward long wave radiation and downward short wave radiation, followed by spring and autumn. The lowest are in winter. As for the net surface radiation, there is obvious decrease in southeast of study area due to returning cropland to grassland. Those research conclusions can offer valuable information for the land use planning and relieving the effects of land cover change on climate change at the semiarid grassland area.

1 Institute of Geographic Sciences and Natural Resources Research, Chinese Academy of Sciences (CAS), Beijing 100101, China 2Department of Geography, Delhi School of Economics, University of Delhi, Delhi 110007, India 3School of Soil and Water Conservation, Beijing Forestry University, Beijing 100038, China 4Department of Microbiology and Plant Biology, Center for Spatial Analysis, University of Oklahoma, Norman, OK 73019, USA 5Department of Civil, Environmental and Geomatics Engineering, Florida Atlantic University, Boca Raton, FL 33431-0991, USA