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With the rapid development of urban agglomerations in northwest arid and semiarid regions of China, the scope of the urban heat island (UHI) effect has gradually expanded and gradually connected, and has formed a regional heat island (RHI) with a larger range of impact to the regional environment. However, there are few studies on the heat island effect of urban agglomerations in arid and semiarid regions, so this paper selects the urban agglomeration of Hohhot, Baotou and Ordos (HBO) of Inner Mongolia, China as the study area. Based on the 8-day composite Moderate-resolution Imaging Spectroradiometer (MODIS) surface temperature data (156 scenes in all) and land use maps for 2005, 2010, and 2015, we analyze the spatiotemporal distributions of regional heat (cool) islands (RH(C)I) and the responses of surface temperatures to land-use changes in the diurnal and interannual surface cities. The results showed that: 1) from 2005 to 2015, urban areas showed the cold island effect during the day, with the area of the cold island showing a shrinking feature; at night, they showed the heat island effect, with the area of the heat island showing a first decrease and then an increase. 2) From 2005 to 2015, the land development (unutilized land to building land) brings the greatest temperature increase (ΔT = 1.36°C) during the day, while the greatest temperature change at night corresponds to the conversion of cultivated land to building land (ΔT = 0.78°C) exhibited the largest changes at night. From 2010 to 2015, the land development (grassland to building land) bring the greatest temperature increase (ΔT = 0.85°C) during the day, while the great temperature change at night corresponds to the conversion of water areas to building land (ΔT = 1.38°C) exhibited the largest changes at night. Exploring the spatial and temporal evolution of surface urban heat (cool) islands in urban agglomerations in arid and semiarid regions will help to understand the urbanization characteristics of urban agglomerations and provide a reference for the formulation of policies for the coordinated and healthy development of the region and co-governance of regional environmental problems. [ABSTRACT FROM AUTHOR]

Three-North Shelterbelt Forest (TSF) program, is one of six key forestry programs and has a 73-year construction period, from 1978 to 2050. Quantitative analysis of the carbon sequestration of shrubs in this region is important for understanding the overall function of carbon sequestration of the forest and other terrestrial ecosystems in China. This study investigated the distribution area of shrubland in the TSF region based on remote sensing images in 1978 and 2008, and calculated the carbon density of shrubland in combination with the field investigation and previous data from published papers. The carbon sequestration quantity and rate from 1978 to 2008 was analyzed for four sub-regions and different types of shrubs in the TSF region. The results revealed that: 1) The area of shrubland in the study area and its four sub-regions increased during the past thirty years. The area of shrubland for the whole region in 2008 was 1.2 × 10 ha, 72.8% larger than that in 1978. The Inner Mongolia-Xinjiang Sub-region was the largest shrubland distribution area, while the highest coverage rate was found in the North China Sub-region. 2) In decreasing order of their carbon sequestration, the four types of shrubs considered in this study were Hippophae rhamnoides, Caragana spp., Haloxylon ammodendron and Vitex negundo var. heterophylla. The carbon sequestration of H. rhamnoides, with a maximum mean carbon density of 16.5 Mg C/ha, was significantly higher than that of the other three species. 3) The total carbon sequestration of shrubland in the study region was 4.5 × 10 Mg C with a mean annual carbon sequestration of 1.5 × 10 Mg C. The carbon density in the four sub-regions decreased in the following order: the Loess Plateau Sub-region, the North China Sub-region, the Northeast China Sub-region and the Inner Mongolia-Xinjiang Sub-region. The paucity of studies and data availability on the large-scale carbon sequestration of shrub species suggests this study provides a baseline reference for future research in this area. [ABSTRACT FROM AUTHOR]

In this paper, we proposed a framework for evaluating the performance of ecosystem strategies prepared for enhancing vulnerability reduction in the face of hazards due to climate change. The framework highlights the positive effects of human activities in the coupled human and natural system (CHANS) by introducing adaptive capacity as an evaluation criterion. A built-in regional vulnerability to a certain hazard was generated based upon interaction of three dimensions of vulnerability: exposure, sensitivity and adaptive capacity. We illustrated the application of this framework in the temperate farming-grazing transitional zone in the middle Inner Mongolia of the northern China, where drought hazard is the key threat to the CHANS. Specific indices were produced to translate such climate variance and social-economic differences into specific indicators. The results showed that the most exposed regions are the inner land areas, while counties located in the eastern part are potentially the most adaptive ones. Ordos City and Bayannur City are most frequently influenced by multiple climate variances, showing highest sensitivity. Analysis also indicated that differences in the ability to adapt to changes are the main causes of spatial differences. After depiction of the spatial differentiations and analysis of the reasons, climate zones were divided to depict the differences in facing to the drought threats. The climate zones were shown to be similar to vulnerability zones based on the quantitative structure of indexes drafted by a triangular map. Further analysis of the composition of the vulnerability index showed that the evaluation criteria were effective in validating the spatial differentiation but potentially ineffective because of their limited time scope. This research will be a demonstration of how to combine the three dimensions by quantitative methods and will thus provide a guide for government to vulnerability reduction management. [ABSTRACT FROM AUTHOR]

The research on ecosystem service values (ESVs) estimation in arid region is weak. We took the Alxa League of China's Inner Mongolia Autonomous Region, an extreme arid region, as an example and constructed an equivalent coefficient method to assess its ESVs from 1975 to 2015, by determining the standard unit of ESVs and the basic equivalent of the value of different ecosystem services per unit area based on the regional characteristics, literature research, expert knowledge and land use data. The results show that the ESVs first decreased from 83 170.4 million yuan (RMB) in 1975 to 82 337.8 million yuan (RMB) in 2000 and then increased to 84 033.6 million yuan (RMB) in 2015, and the ESV of sparse grassland and desert account for about 33% and 29% of the total ESVs, respectively. Among the four service types, the regulating services, support services, supply services and cultural services account for 66.5%, 22.8%, 6.0% and 4.7%, respectively. The changes of ESVs in Alxa League are determined by the socio-economic development and ecological changes. This study provides a new method to estimate the ESVs in arid region by integrating existing methods and regional characteristics, such as the cost of water for arid ecosystems. [ABSTRACT FROM AUTHOR]

The semi-arid grasslands in Inner Mongolia, China have been degraded by long-term grazing. A series of ecological restoration strategies have been implemented to improve grassland service. However, little is known about the effect of these ecological restoration practices on soil carbon and nitrogen storage. In this study, characteristics of vegetation and soil properties under continued grazing and exclusion of livestock for six years due to a nationwide conservation program-'Returning Grazing Lands to Grasslands (RGLG)' were examined in semi-arid Hulun Buir grassland in Inner Mongolia, China. The results show that removal of grazing for six years resulted in a significant recovery in vegetation with higher above and below-ground biomass, but a lower soil bulk density and pH value. After six years of grazing exclusion, soil organic C and total N storage increased by 13.9% and 17.1%, respectively, which could be partly explained by decreased loss and increased input of C and N to soil. The effects of grazing exclusion on soil C and N concentration and storage primarily occurred in the upper soil depths. The results indicate that removal of grazing pressure within the RGLG program was an effective restoration approach to control grassland degradation in this region. However, more comprehensive studies are needed to evaluate the effectiveness of the RGLG program and to improve the management strategies for grassland restoration in this area. [ABSTRACT FROM AUTHOR]

Land change science (LCS) strives to understand and model land-use change, which will further advance the understanding of multiple issues in the socio-ecological systems. Based on GIS/RS techniques, autologistic model, and household survey method, this study investigated major land use changes and their causes from 1978 to 2008 in Uxin Banner (county-level), Inner Mongolia in China and then developed an understanding of the relationships between household livelihood and land-use pattern. Results showed that cultivated land increased from 1988 to 2000, and leveled off after 2000. Built-up land increased stably for the period 1978–2008. The change of grassland and bare land differed among the three periods. From 1978 to 1988, grassland increased by 23.3%, and bare land decreased by 20.48%. From 1988 to 2000, bare land expanded by 1.7%, but grassland declined by 1.3%. From 2000 to 2008, an increase in grassland area by 1.8% was observed, but a decrease in bare land area by 9.0% was witnessed. The autologistic models performed better than logistic models as indicated by lower Akaike Information Criterion (AIC) values. Factors associated with human activities significantly correlated with the change of cultivated land, forest land, grassland, and built-up land. The produce prices and extensive cultivated land use are major issues in the farming area. This study suggests that completing land circulation systems and maintaining the stability of price are effective solutions. By contrast, reclamation and overgrazing are major concerns in the pastoral areas. Implementing environmental policies effectively, transferring population out of rural pastoral areas, and developing modern animal husbandry are effective ways to address these issues. [ABSTRACT FROM AUTHOR]

Under the increasing pressure of water shortage and steppe degradation, information on the hydrological cycle in steppe region in Inner Mongolia, China is urgently needed. An intensive investigation of the temporal variations of δD and δO in precipitation was conducted in 2007-2008 in the Xilin River Basin, Inner Mongolia in the northern China. The δD and δO values for 54 precipitation samples range from +1.1‰ to −34.7‰ and −3.0‰ to −269‰, respectively. This wide range indicates that stable isotopes in precipitation are primarily controlled by different condensation mechanisms as a function of air temperature and varying sources of vapor. The relationship between δD and δO defined a well constrained line given by δD = 7.89 δ O + 9.5, which is nearly identical to the Meteoric Water Line in the northern China. The temperature effect is clearly displayed in this area. The results of backward trajectory of each precipitation day show that the vapor of the precipitation in cold season (October to March) mainly originates from the west while the moisture source is more complicated in warm season (April to September). A light precipitation amount effect existes at the precipitation event scale in this area. The vapor source of precipitation with higher d-excesses are mainly from the west wind or neighboring inland area and precipitation with lower d-excesses from a monsoon source from the southeastern China. [ABSTRACT FROM AUTHOR]