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Background: Grazing exclusion is an efficient practice to restore degraded grassland ecosystems by eliminating external disturbances and improving ecosystems' self-healing capacities, which affects the ecological processes of soil-plant systems. Grassland degradation levels play a critical role in regulating these ecological processes. However, the effects of vegetation and soil states at different degradation stages on grassland ecosystem restoration are not fully understood. To better understand this, desert steppe at three levels of degradation (light, moderate, and heavy degradation) was fenced for 6 years in Inner Mongolia, China. Community characteristics were investigated, and nutrient concentrations of the soil (0–10 cm depth) and dominant plants were measured. Results: We found that grazing exclusion increased shoots' carbon (C) concentrations, C/N, and C/P, but significantly decreased shoots' nitrogen (N) and phosphorus (P) concentrations for Stipa breviflora and Cleistogenes songorica. Interestingly, there were no significant differences in nutrient concentrations of these two species among the three degraded desert steppes after grazing exclusion. After grazing exclusion, annual accumulation rates of aboveground C, N, and P pools in the heavily degraded area were the highest, but the aboveground nutrient pools were the lowest among the three degraded grasslands. Similarly, the annual recovery rates of community height, cover, and aboveground biomass in the heavily degraded desert steppe were the highest among the three degraded steppes after grazing exclusion. These results indicate that grazing exclusion is more effective for vegetation restoration in the heavily degraded desert steppe. The soil total carbon, total nitrogen, total phosphorus, available nitrogen, and available phosphorus concentrations in the moderately and heavily degraded desert steppes were significantly decreased after six years of grazing exclusion, whereas these were no changes in the lightly degraded desert steppe. Structural equation model analysis showed that the grassland degradation level mainly altered the community aboveground biomass and aboveground nutrient pool, driving the decrease in soil nutrient concentrations and accelerating nutrient transfer from soil to plant community, especially in the heavily degraded grassland. Conclusions: Our study emphasizes the importance of grassland degradation level in ecosystem restoration and provides theoretical guidance for scientific formulation of containment policies. [ABSTRACT FROM AUTHOR]

Global surface temperature is increasing significantly under climate change with increasingly uneven distribution of precipitation, which has been making an important impact on the sustainable development of the dryland agriculture in semi-arid regions. The Inner Mongolia Autonomous Region (IMAR) has the largest area ratio of semi-arid regions in China, and spring wheat is one of its major grain crops, and the negative impacts of climate change pose a serious threat to its production. In order to reduce this threat, we assessed the impact thresholds and risks posed by the main climatic factors to spring-wheat production, and put forward quantitative adaptive countermeasures. The results showed that, from 1961 to 2012, the appropriate impact thresholds of average temperature, precipitation, fertilization level, and water supply level were 15.6 °C, 333 mm, 319.5 kg/ha, and 743.7 mm, respectively. Compared with the average values in 1996–2012, the maximum fertilization level and water supply level could be increased by 162.2 kg/ha and 406.5 mm, respectively, to improve the adaptive yield of spring wheat. The risks of adverse impacts of temperature rise, precipitation decrease, and their combined effect on spring-wheat production were found to be 11.1%, 9.3%, and 10.3%, respectively. The whole IMAR showed a high risk of adverse impacts of temperature rise and the combined action of temperature rise and precipitation decrease on spring-wheat production. In particular, the spring-wheat production in the northeastern, eastern, and central areas were found to be at the highest risk to the impacts of climate change. Based on the determined appropriate thresholds of fertilization level and water supply level, it was determined that in the northeastern area, the maximum fertilization level and water supply level could be increased by 229.9 kg/ha and 441.4 mm, respectively, to increase the adaptive yield of spring wheat. In the eastern area, the two factors could be increased by 142.2 kg/ha and 464.3 mm, respectively. In the central area, they could be increased by 242.2 kg/ha and 513.7 mm, respectively. In the southwestern area, they could be increased by 41.4 kg/ha and 201.7 mm, respectively. [ABSTRACT FROM AUTHOR]

The mineral system modeling approach for prospectivity mapping is an efficient and economic method to assess undiscovered mineral potential quantitatively. It is a procedure of modeling, acquiring, and coupling the proxies of footprints of mineral systems at multiple scales (e.g., regional, district, and deposit scales). In this approach, the critical issue from multiple scales is that the data collected are asymmetrical from the superficial to the deep or from mine to its brown fields, so that it is hard to employ and integrate them. To complete this study, firstly, multi-tactic 3D geological modeling methods, including the explicit, the implicit, and inversion, were used to build geological models in the condition of asymmetrical datasets at the deposit and district scales. Secondly, indicators acquired in drill-intensive fields among multisource datasets composed of geology, geochemistry, geophysics and alteration data were transferred to studies in deep and brown fields. Finally, deep (~ 1,100 m) and circumjacent potentials of mine were targeted in the Haoyaoerhudong gold deposit situated in the Urad Middle Banner area, Inner Mongolia, which is one of the largest black-rock-series-type gold mines in China. This proposed procedure is more visual, clear, intuitive, and transferable to drive mineral system approach to exploration discovery than previous GIS-based studies. [ABSTRACT FROM AUTHOR]

Natural radioactivity due to 226Ra, 232Th and 40K in the common building materials collected from Baotou city of Inner Mongolia, China was measured using gamma-ray spectrometry. The radiation hazard of the studied building materials was estimated by the radium equivalent activity (Raeq), internal hazard index (Hin) and annual effective dose (AED). The concentrations of the natural radionuclides and Raeq in the studied samples were compared with the corresponding results of other countries. The Raeq values of the building materials are below the internationally accepted values (370 Bq kg−1). The values of Hin in all studied building materials are less than unity. The AEDs of all measured building materials are at an acceptable level. [ABSTRACT FROM AUTHOR]

• A GIS-based professional package for mineral resources assessment was developed. • SDE and Terrain Rendering were used to manage datasets and visualization. • A gold mineral resources assessment was conducted in Inner Mongolia by the GIS tool. This paper describes a software tool and its application to the China National Mineral Resource Assessment Initiative (CNMRAI). The initiative was carried out throughout China from 2007 to 2013, creating collaborations among geological societies from institutions such as academies, universities, companies, and local geological surveys. A geographic information system (GIS)-based tool was designed, providing functions for database management of the multiple original spatial datasets, modelling, targeting, estimation, and visualization to assist participants in assessing mineral resource potentials. During this initiative, geologists used the tool to generate mineral potential maps and assess undiscovered resources for the 25 major types of mineral resources in China. First, the requirements of the tool were introduced; second, the framework and major functions of the tool were delineated and developed; and third, a case study of gold resource assessment from a project of the CNMRAI in the Bayan Obo region, Inner Mongolia, China, was discussed. In addition, the mineral potential map was displayed by terrain rendering. This paper also provides interpretations of the results of a prospectivity analysis based on conceptual geological models. Discussions of the new requirements and techniques for modelling and assessing will be used to further develop the Mineral Resources Assessment Software (MRAS). [ABSTRACT FROM AUTHOR]