区域资源环境综合承载力研究进展与展望

区域资源环境综合承载力是人地关系和谐和可持续发展的重要基础,也是自然地理综合研究的前沿及热点内容。近年来,区域资源环境综合承载力研究取得了长足进展,体现在：①建立了综合、广泛的评价指标体系;②资源环境综合承载力与人地关系的调适;③综合研究方法的应用;④对资源环境综合承载力的时空动态研究的关注及尝试。目前,资源环境综合承载力研究应用于国土空间开发、产业规划、灾后重建、资源环境监测及预警等领域。未来仍需在完善指标体系的构建、研究尺度及动态变化等方面加强研究,以此深化综合自然地理理论及实践研究,为区域资源、社会和生态环境可持续性研究提供支撑。     

Mining transition rules of cellular automata for simulating urban expansion by using the deep learning techniques

Along with the gradually accelerated urbanization process, simulating and predicting the future pattern of the city is of great importance to the prediction and prevention of some environmental, economic and urban issues. Previous studies have generally integrated traditional machine learning with cellular automaton (CA) models to simulate urban development. Nevertheless, difficulties still exist in the process of obtaining more accurate results with CA models; such difficulties are mainly due to the insufficient consideration of neighborhood effects during urban transition rule mining. In this paper, we used an effective deep learning method, named convolution neural network for united mining (UMCNN), to solve the problem. UMCNN has substantial potential to get neighborhood information from its receptive field. Thus, a novel CA model coupled with UMCNN and Markov chain was designed to improve the performance of simulating urban expansion processes. Choosing the Pearl River Delta of China as the study area, we excavate the driving factors and the transformational relations revealed by the urban land-use patterns in 2000, 2005 and 2010 and further simulate the urban expansion status in 2020 and 2030. Additionally, three traditional machine-learning-based CA models (LR, ANN and RFA) are built to attest the practicality of the proposed model. In the comparison, the proposed method reaches the highest simulation accuracy and landscape index similarity. The predicted urban expansion results reveal that the economy will continue to be the primary factor in the study area from 2010 to 2030. The proposed model can serve as guidance in urban planning and government decision-making.     

The Progress of Resources and Environment Carrying Capacity: from Single-factor Carrying Capacity Research to Comprehensive Research

As a concept to describe development restrictions, resources and environment carrying capacity (RECC) research has developed over more than 100 years since it was first proposed at the beginning of the 20^th century. It is now regarded as a significant factor in evaluating the level of cooperation between regional population, resources, and environment; and it is currently used as an effective and operational tool to guide regional sustainable development. This article first reviews the origin of RECC and its early headway. It then reviews the historical development of RECC from single factors, such as land resources carrying capacity, water resources carrying capacity and environmental carrying capacity (environmental capacity), to more comprehensive research, such as comprehensive evaluation, emergy analysis, and ecological footprint analysis. In general, it appears that comprehensive research will become increasingly important in RECC research. However, there are several deficiencies in the current state of comprehensive research. Firstly, comprehensive RECC research lacks a common measurement standard, though some scholars have attempted to create one. Secondly, the RECC evaluation of open systems and dynamic studies should be strengthened. Thirdly, more attention should be paid to standardization, digitalization, and systematization to promote the applicability of RECC research to national practical demands.     

Regional Differentiation and Classification for Carrying Constraints on the Resources and Environment of China

Research on the relationship between national resource constraint-region types and environmental carrying capacity is essential for the continued development of Chinese industrialization and urbanization. Thus, utilizing a series of key indexes including the per-capita potential of available land resources, the per-capita potential of available water resources, the degree of environmental stress, and the degree of ecological restriction, a step-by-step, integrated measuring method is presented here to understand the constrained carrying elements of water and land resources as well as environment and ecology. Spatial differences are analyzed and area types classified at the county level across China. Results reveal that: (1) Almost 90% of China is strongly constrained by both resources and the environment, while nearly 50% of national territory is strongly constrained by two elements, especially in areas of intensive population and industry to the east of the Helan-Longmen Mountain line; (2) Densely populated areas of eastern and central China, as well as on the Tibetan Plateau, are strongly constrained by a shortage of land resources, while North China, the northwest, northeast, the Sichuan basin, and some southern cities are experiencing strong constraints because of water shortages. In contrast, the North China plain, the Yangtze River delta, northern Jiangsu, Sichuan province, Chongqing municipality, Guizhou and Guangxi provinces, the northeast plain, and the northern Loess Plateau are constrained by high levels of environmental stress. Areas of China that are strongly ecologically constrained tend to be concentrated to the southwest of the Tianshan-Dabie Mountain line, as well as in the northeast on the Loess Plateau, in the Alashan of Inner Mongolia, in northeast China, and in the northern Jiangsu coastal area; (3) Constraints on national resources and environmental carrying capacity are diverse and cross-cut China, meanwhile, multi-element spatial distribution does reveal a degree of relative centralization. With the exception of the Tibetan Plateau which is resources-ecological constraint , other areas subject to cross constraints are mainly concentrated to the east of the Helan-Longmen Mountain line.     

Analysis of the Water Environmental Capacity of Zhongba-Nyingchi Section of the Yarlung Tsangpo River

The Yarlung Tsangpo River, the longest river in Tibet, houses most of the population and economy in Tibet Autonomous province. Under the rapid development of economy and society in Tibet, the pollution in the Yarlung Tsangpo River basin has rapidly increased. Evaluating water quality and water environmental capacity is needed for water resource management in Tibet. This study used a single factor evaluation method to evaluate water quality of the Zhongba-Nyingchi section of the Yarlung Tsangpo River based on measured data of COD_Cr, NH3-N and TP in the study area. Based on these data, determinations of ideal water environmental capacity, emissions of pollutants and remaining water environmental capacity of the study area were made by a one-dimensional steady water quality model under either section-head control or cross-section control. The data indicate that most of the monitoring sections in the study area experienced good water quality. The three pollutants all had large remaining water environmental capacity generally, but TP exceeded state levels in the two upstream functional areas, and levels above state standards of COD_Cr and TP were found in several calculation cells of the two downstream functional areas. Therefore, emissions of pollutants need to be reduced to protect the water environment quality of the Yarlung Tsangpo River.     

Overflow probability of the Salt Lake in Hoh Xil Region

After the bursting of Huiten Nor in Hoh Xil Region in September, 2011, the topic on whether the water overflowed from the Salt Lake would enter into the Chumaer River and become the northernmost source of the Yangtze River has aroused wide concern from public and academic field. Based on Landsat TM/ETM+/OLI remote sensing images during 2010–2015, SRTM 1 arc-second data, Google Earth elevation data and the observation data from the Wudaoliang meteorological station, the study initially analyzed the variations of the Salt Lake and its overflowing condition and probability. The results showed that the area of the Salt Lake expanded sharply from October 2011 to April 2013, and then it stepped into a stable expansion period. On October 27, 2015, the area of the Salt Lake had arrived at 151.38 km², which was about 3.35 times the area of the lake on March 3, 2010. The Salt Lake will overflow when its area reaches the range from 218.90 km² to 220.63 km². Due to the differences between SRTM DEM and Google Earth elevation data, the water level of the Salt Lake simulated would be 12 m or 9.6 m higher than the current level when the lake overflowed, and its reservoir capacity would increase by 23.71 km³ or 17.27 km³, respectively. Meanwhile, the overflowed water of the Salt Lake would run into the Qingshui River basin from its eastern part. Although the Salt Lake does not overflow in the coming decade, with watershed expansion of the Salt Lake and the projected precipitation increase in Hoh Xil region, the probability of water overflow from the Salt Lake and becoming a tributary of the Yangtze River will exist in the long term.     

The role of adaptive capacity in incremental and transformative adaptation in three large U.S. Urban water systems

Urban water systems need to serve increasing numbers of people under a changing climate. Studies of systems facing extreme events, such as drought, can clarify the nature of adaptive capacity and whether this might support incremental (marginal changes) or transformative adaptation (fundamental system shifts) to climate change. We conducted comparative case studies of three major metropolitan water systems in the United States to understand how actions taken in response to drought affected adaptive capacity and whether the adaptive capacity observed in these systems fosters the preconditions needed for transformative adaptation. We find that while there is ample evidence of existing and potential adaptive capacity, this can be either enabled or diminished by the specific actions taken and their cascading effects on other parts of the system. We also find social dimensions, such as public acceptance, learning, trust, and collaboration, to be as critical as physical elements of adaptive capacity in urban water systems. Finally, we suggest that changes in practices initiated during drought, combined with sustained engagement, collaboration, and education, can lead to substantial and long-lasting changes in values around water, a precursor to transformative adaptation.     

X射线荧光光谱法测定铁矿中铁等多种元素

采用熔融片制样,加入钴元素(Co Kα)作铁的内标,用X射线荧光光谱法测定铁等多种元素。用多种类型铁矿标准样品作为校准,理论α系数内标法及康普敦散射作内标校正基体效应。方法的最大绝对误差AE(TFe)≤0.23%,满足了ISO 9507对TFe分析结果准确度的要求[AE(TFe)≤0.3%]。     

X射线荧光光谱法测定锌铝硅合金中硅和铁

采用岛津MXF-2400型多道X荧光光谱仪测定锌铝硅合金中硅及铁的含量,对样品分析面进行了选择,考察了分析面光洁度、样品放置时间对测定的影响条件。方法样品前期处理简便,分析速度快,灵敏度高,硅和铁的相对标准偏差(RSD,n=11)分别为1.15%和0.44%。与其他方法对照,结果相符。     

Regional search, selection and geological characterization of a large anticlinal structure, as a candidate site for CO2-storage in northern Germany

This paper reports on the regional screening, selection and geological characterisation of a potential on-shore CO₂ storage site (saline aquifer) in north-eastern Germany. The main objective of this study was to identify and investigate a candidate storage site, capable to accommodate the total amount of approximately 400 million tons of CO₂. Such a volume is produced by a modern, lignite-fired power plant within its operation lifetime of approximately 40 years. Within north-eastern Germany, several saline aquifers of Triassic, Jurassic and Cretaceous age have been evaluated with respect to their regional occurrence, storage potential and basic reservoir properties. Subsequent to a ranking, considering different criteria, the anticlinal structure Schweinrich holding suitable saline aquifers of the uppermost Triassic and lowest Jurassic has been selected from a number of identified candidate sites. According to results of the geological site characterisation, including structural geological investigations and 3D reservoir modelling, the structure Schweinrich seems to be a suitable site for industrial large scale CO₂ storage. Further data acquisition (new wells and 3D seismics) and research (more detailed and comprehensive modelling) is needed in order to prove the structural integrity of the storage site and assure long-term safety.