The history of dune landform changes and dust activity at mid-latitudes is a good archive for exploring environmental changes and related landscape response. In this study, the dynamic changes, material sources, dust activity history and the influencing factors of typical sand dunes in the Hexi Corridor were comprehensively analyzed from the aspects of aeolian geomorphology, grain-size sedimentology, geochemistry and climatology. The results show that in the past half century, the typical crescent-shaped dunes and chains of crescent-shaped dunes in the study area have moved or swayed greatly, with an average speed ranging from 0.8 m/a (Dunhuang) to 6.2 m/a (Minqin). The dynamic changes of sand dunes are mainly affected by annual precipitation, annual average wind speed and annual gale days, which indicates that climate is the primary influencing factor of dune landform changes. The three-stage grain-size curve model of dune sands is obviously different from that of gobi sediments (two-stage), revealing the “immaturity” of the latter in sedimentology, while the former has experienced efficiently aeolian differentiation and non-local origin. The comprehensive evidences of paleogeography, sedimentology and geochemistry reveal that the source materials of sand dunes are mainly alluvial/proluvial and palaeo-fluvial sediments, including clastic sediments in the denudation/erosion zones of the north and south piedmonts. Indicators such as the proportion of surface fine particles, the coverage of surface salt crusts, and the content of erodible sandy materials indicate that the western gobi areas are not the main source areas of wind-blown dust in the central and eastern parts of the Hexi Corridor. The spatial distribution of the movement direction of sand dunes is similar to that of the regional dominant wind direction, which indicates that the difference in the dynamic evolution of dune landforms between the east and west of the Hexi Corridor should be controlled by the regional-scale wind system, that is, controlled by the dynamic mechanism rather than the difference in material sources. The warming and humidification of the Hexi climate is a synchronous response to the global warming and the strengthening of the Asian Summer Monsoon. It is also the main reason for the reduction of dust storms in the study area, which means that a potential inverse desertification process exists in the Hexi Corridor during the same period and it is also controlled by climate change. However, the process of desertification in the oasis areas during the period is caused by groundwater fluctuation affected by human activities.

The spatial distributions and variation mechanism of key soil indices in the Qinling-Daba Mountains are important indicators for the identification of the transitional effect and regional characteristics of the north-south transitional zone in China. This manuscript analyzes the spatial variations in soil organic carbon (SOC) and total nitrogen (TN) and corresponding relationships with major geographical factors based on spatial analysis and geostatistics considering data obtained from the Second National Soil Survey. The results indicate that the spatial distributions of the SOC and TN contents are consistent, and three high-content areas, one secondary high-content area and one low-content area are observed. High content values are located in the high-altitude regions of the Qinling-Daba Mountains and mountainous areas to the west of the Jialing River, the low-content area occurs on the north slope of the Qinling Mountains, and the secondary high-content area mainly encompasses both sides of the Hanjiang River and regions in the Qinling-Daba Mountains at altitudes below 1000 m. The SOC and TN contents vary between the above two ranges, with the gradual increase in content revealing a horn-shaped pattern. Considering the spatial variations and functions of vegetation, topography and climate factors, it is found that the SOC/TN range in the secondary high-content area remains consistent along the 1000 m contour line, the upper limit of the transitional mountain altitudinal belt, the 0°C isotherm line in January and the 24°C isotherm line in July. This region constitutes the main body of the transitional zone between the subtropical and warm temperate zones, and the northern boundary is roughly distributed along the Dujiangyan-Maoxian-Pingwu-Wenxian line to the west of the Jialing River and the 1000 m contour line on the southern slope of the Qinling Mountains, while the southern boundary occurs along the Dujiangyan-Beichuan-Qingchuan line to the west of the Jialing River and the 1000 m contour line on the northern slope of the Daba Mountains. SOC/TN spatial variation provides a reference for the demarcation of the subtropical and warm temperate zones, and further identification of the soil processes and ecological effects in typical regions can help reveal multidimensional transitional characteristics and variation mechanisms.

Studying an ecological restoration zoning process under the background of ecological security patterns is of great significance to the rapid adjustment and optimization of a landscape pattern. In this study, a remote sensing ecological index and a morphological spatial pattern analysis method were used to assess the quality of habitats and identify ecological sources in the city of Ningbo; ecological corridors, ecological pinch points, and ecological barrier points were extracted by using a circuit theory to construct ecological security patterns and ecological restoration zones. The results indicate: (1) There were 47 ecological sources, and 83 key ecological corridors in Ningbo, and the ecological land area was about 1898.39 km², accounting for 19.89% of the total study area. (2) The ecological source areas were distributed in “one patch and three belts”, and the low-resistance ecological corridors were concentrated in southern Yuyao city, western Haishu district, and central and western Fenghua district; the ecological network in the western and southern regions was dense. (3) There were four types of ecological restoration zones that need to be established, which were prioritized restoration zones, prioritized protection zones, key conservation zones, and general conservation zones distributed hierarchically from inner part towards outside. (4) Ninghai county, Yuyao city, and Fenghua district had large ecological land areas, however, prioritized restoration and protection zones in Ninghai and Fenghua were also large. The analysis results are expected to provide a reference for optimizing a territorial ecological space in a city.

Land ecological security (LES) is an important part of China’s ecological civilization construction, which plays a vital role in ensuring the sustainable development of its society and economy. Based on the Driving force-Pressure-State-Impact-Response (DPSIR) framework, this study quantified the spatiotemporal changes of LES in 28 counties of the southern Shaanxi Province from 2009 to 2018. The influencing factors of LES in Yangxian County were explored to clarify the mechanisms that rely on the land ecological advantages to develop organic agriculture and boost poverty alleviation. Results show that the LES of Yangxian always ranked in the top six in 28 counties of the southern Shaanxi region during 2009-2018. The LES in Yangxian increased from 0.385 in 2009 to 0.533 in 2018, and the LES level changed from relatively unsafe to safe. The indicators of rural per capita net income, grain output per unit area of arable land, and grazing intensity could explain 99.8% of the LES variance in Yangxian. Relying on ecological resources, Yangxian increased farmers’ income and boosted alleviation of poverty through innovative land policies, developing organic agriculture, and rural tourism. These findings will provide theoretical support and model reference for balancing ecological protection and poverty alleviation in restricted development zones.

Land use patterns (LUPs) are the form in which various land use types are combined spatially, evidently impacting soil water. However, the influence mechanism by which LUPs form remains unclear. In this study, the soil water content (SWC) in the 0-160-cm soil depth was observed in shrubland (SL), mature forestland (MF), grassland (GL) and young forestland (YF) sites on four slopes with different LUPs in the Yangjuangou catchment of the Chinese Loess Plateau. The SWC in SL-YF-SL (13.28%) was significantly greater than that in YF-MF (9.93%), MF-GL-YF (10.38%) and SL-MF (10.83%) and was temporally stable during the study period. The spatial distribution of SWC along the slope differed among the four LUPs. Vegetation characteristics and soil texture mainly determined the spatial variations in SWC in the shallow soil layers (0-40 cm), while topographic factors were the determinants in the deep soil layers (60-160 cm) as well as in the entire soil profile (0-160 cm). The significance of SWC differences among the various land use patterns increased with decreasing precipitation during the growing seasons. YF-MF (77.8 mm) and SL-YF-GL (73.9 mm) required more rainwater than SL-MF (68.2 mm) and MF-GL-MF (67.5 mm) to compensate for the loss of soil water on the monthly scale during the rainy season. Therefore, vegetation restoration should consider land use patterns on hillslopes for soil water conservation.

During the 21st century, artificial intelligence methods have been broadly applied in geosciences to simulate complex dynamic ecosystems, but the use of artificial intelligence (AI) methods to reproduce land-use/cover change (LUCC) in arid ecosystems remains rare. This paper presents a hybrid modeling approach to understand the complexity in LUCC. Fuzzy logic, equation-based systems, and expert systems are combined to predict LUCC as determined by water resources and other factors. The driving factors of LUCC in this study include climate change, ecological flooding, groundwater conditions, and human activities. The increase of natural flooding was found to be effective in preventing vegetation degradation. LUCCs are sensitive under different climate projections of RCP2.6, RCP4.5, and RCP8.5. Simulation results indicate that the increase of precipitation is not able to compensate for the additional evaporation losses resulting from temperature increases. The results indicate that grassland, shrub, and riparian forest regions will shrink in this study area. The change in grasslands has a strong negative correlation with the change in groundwater salinity, whereas forest change had a strong positive correlation with ecological flooding. The application of artificial intelligence to study LUCC can guide land management policies and make predictions regarding land degradation.

Groundwater resources have always been some of the most valuable resources of human settlements. Climate changes and ever-increasing water demands registered in the last century have led to diminishing levels of groundwater reserves, as well as reduced recharging potential. Therefore, in order to use groundwater aquifers in a sustainable manner, it is required to identify areas with higher replenishing potential. The current study addresses the issue of generating a map for identifying differently ranked groundwater recharging potential values, in the aquifers of the Moldavian Plain region, Romania. For the purpose of conducting the analysis, maps were created through GIS based multi-criteria Analytic Hierarchy Process (AHP) and Catastrophe Theory (CT), with seven relevant, thematic, spatial layers: precipitation distribution, lithological strata, soil texture, declivity, drainage density, land use and the distribution of groundwater level tendencies. The results of the two methods of analysis are similar. Prediction differences are of maximum 3%, in the case of extreme classes (very bad and very good) and in the case of middle classes the deviation is not greater than 0.4%. Following the validation of the results generated by the two methods that were applied, it was observed that the predictions offered by CT are more accurate. This aspect can be based on the fact that the main factors that contribute to the prediction are different. This type of workflow emphasizes the necessity of implementing appropriate groundwater management plans for mitigating reservoir scarcity/depletion, and recommending sustainable solutions for future groundwater exploitation practices.

Patent transfer has been regarded as an important channel for the nations and regions to acquire external technology, and also a direct research object to depict the relationship between supply and demand of technology flow. Therefore, based on traceable patent transfer data, this article has established a dual-pipeline theoretical framework of transnational-domestic technology transfer from the interaction of the global and local (glocal) perspective, and combines social networks, GIS spatial analysis as well as spatial econometric model to discover the spatial evolution of China’s transnational technology channels and its determinant factors. It is found that: (1) The spatial heterogeneity of the overall network is significant while gradually weakened over time. (2) The eastward shift of the core cities involved in transnational technology channels is accelerating, from the hubs in North America (New York Bay Area, Silicon Valley, Caribbean offshore financial center, etc.) and West Europe (London offshore financial center etc.) to East Asia (Tokyo and Seoul) and Southeast Asia (Singapore), which illustrates China has decreased reliance on the technology from the USA and West Europe. (3) The four major innovation clusters: Beijing-Tianjin-Hebei region (Beijing as the hub), Yangtze River Delta (Shanghai as the hub), The Greater Bay Area (Shenzhen and Hong Kong as the hubs) and north Taiwan (Taipei and Hsinchu as the hubs), are regarded as global technology innovation hubs and China’s distribution centers in transnational technology flow. Among those, Chinese Hong Kong’s betweenness role of technology is strengthened due to linkage of transnational corporations and their branches, and low tax coverage of offshore finance, thus becoming the top city for technology transfer. Meanwhile, Chinese Taiwan’s core position is diminishing. (4) The breadth, intensity, and closeness of domestic technology transfer are conducive to the expansion of transnational technology import channels. Additionally, local economic level has positive effect on transnational technology transfer channels while technology strength and external economic linkage have multifaceted influences.

With the rise of smart phones, mobile applications have been widely used in daily life. However, the relationship between individuals’ mobile application usage and cities’ economic development has yet to be investigated. To study this question, this work utilizes a dataset containing users’ history of mobile application usage records (MAURs) and investigates how MAURs are related to Chinese cities’ economic development. Our analysis shows the cities’ GDP and number of MAURs are highly correlated, and at the individual level, people in wealthier cities (higher GDP per capita) tend to have more active mobile application usage (MAURs per capita). The results also demonstrate the relevance between cities’ GDP and MAURs varies significantly among different demographic groups, with male users’ relevance consistently higher than female users’ and working-age people’s relevance higher than other age groups. A boosted tree regression model is then applied to predict cities’ GDP with MAURs and proves to achieve high goodness-of-fit (over 0.8 R-square) and good prediction accuracy, especially for the economically developed and populous regions in China. To the best of our knowledge, this is the first time that the relationship between MAURs and cities’ economic development is revealed, which contributes to novel knowledge discovery for regionalization and urban development.

High-quality industrial development (HID) is a requirement of the modern economy and regional development. This paper designed a four-dimensional HID evaluation framework according to the logic of “development foundation-development theme-development subject-development guarantee.” Specifically, momentum cultivation as the foundation, efficiency improvement as the theme, and quality promotion as the subject are the three pivots driving the industrial transformation from high-speed development to high-quality development. A stable economic environment and a harmonious social environment are the guarantees of HID. Choosing the π-shaped Curve Area of the Yellow River basin in China as the study area, this paper measured the spatiotemporal pattern of HID and its four dimensions using the entropy-weighted TOPSIS method based on relevant economic indicators. Besides, the obstacle recognition model was adopted to identify the obstacles to HID. Findings include: From 2005 to 2019, the HID in the Curve Area was characterized by spatial unevenness and relative stability. The industrial structure and industrial layout were more rational in provincial capitals and large cities than in other cities. The spatial organization of the industrial economy presented an incompact polycentric structure, and the industrial association was relatively weak in the curve’s upper reaches. Almost all cities have experienced an increase in single-factor productivity, and technological progress contributed most to the total factor productivity growth. During the study period, the development momentum stabilized at high levels in Inner Mongolia while at low levels in resource-based cities. The development environment in most cities has remained stable, and the social welfare has increased and distributed more equitably in the Area. The technological introduction and the rationalization of the industrial structure were the primary obstacle factors for the Area in realizing HID, and the upgrading of the industrial location index was critical to the upper reaches of the curve. This paper was expected to provide new ideas for studying industrial transformation and practical policy proposals for regional development in the Curve Area.

Over the past 20 years, China has experienced multiple economic transitions characterized by marketization, globalization, decentralization, and urbanization; as a result, urban land development intensity (ULDI) has become a significant issue for sustainable development. As China’s largest globalized urban area, the rapid socio-economic development of the Yangtze River Delta has created a huge demand for urban land. We apply a theoretical framework for a four-dimensional analysis tool to understand the dynamic evolution of the ULDI in the context of economic transition. It reveals that marketization, globalization, decentralization, and urbanization affect the ULDI in the economic transition of Yangtze River Delta. Marketization, especially the continuous improvement of land marketization, optimizes the spatial allocation of land resources and encourages urban land users to improve ULDI. Globalization promotes the rapid growth of economy and population through an increase in foreign direct investment. In the process of decentralization, local governments rely on developing a mode of land finance, resulting in a disordered urban space and low ULDI. Population growth and agglomeration during urbanization stimulates residents’ consumption capacity and promotes economic growth, thus creating a greater demand for urban land. However, a low level of development and utilization restricts the improvement of development intensity. Economic development can improve the level of land-intensive use by promoting the adjustment, optimization, and upgrade of urban industrial structures.

A transportation hub is the key link in the construction of the comprehensive three-dimensional transportation corridor of the Yangtze River Economic Belt, and is the basic factor responsible for the promotion of this belt. A high-speed railway hub has the “last kilometer of time-space compression” effect and is the key to building an efficient, convenient, modern, and comprehensive transportation system. This study constructed a model for measuring the connection-distribution performance of the high-speed railway hub, determined the connection-distribution performance of the urban high-speed railway hub in the Yangtze River Economic Belt, and analyzed its spatial differentiation characteristics, further revealed the influencing mechanism of the connection-distribution performance of the high-speed railway hub. The main results are as follows: (1) The connection-distribution performance of the high-speed railway hub in the Yangtze River Economic Belt presented an “olive-shaped pattern” grade structure with two small ends and a large middle section, that is, the number of high-speed railway stations with high performance and average performance was small, and the number of high-speed railway stations with good performance and medium performance was large. (2) The connection-distribution performance of the high-speed railway hub in the Yangtze River Economic Belt showed a regional differentiation pattern of “high in the east and low in the west” and “high in the north and low in the south”, and showed an urban agglomeration differentiation pattern of “high in the core areas but low in the marginal areas”; moreover, spatial differences were prominent in the distribution of nine evaluation indexes of the connection-distribution performance of the high-speed railway hub. (3) GDP, urbanization rate, city level, station passenger flow and frequency of shuttle bus were key driving factors affecting the connection-distribution performance of the high-speed railway hub. At the same time, there were significant differences in the key driving factors for the connection-distribution performance grades of high-quality, good, medium and average.

China has entered the middle-to-late stage of urbanization. The scale of urban- to-urban migrants, which more refers to the urban-to-urban floating population (UUFP) across China, has significantly increased. UUFP settlement intention is a crucial issue for urbanization development. This study examines the spatial pattern and factors influencing the settlement intention of the UUFP in China based on data obtained through its dynamic monitoring in 2017 and the binary logistic model. The results show that most members of the UUFP were married, older, better educated, and had a higher income than the average person with extensive migration experience. We correlated a high settlement intention with developed economies, coastal areas, good environmental conditions, and more amenities in cities such as Beijing, Tianjin, Shanghai, and Zhuhai. Amenities were more impactful on settlement intention than economic factors, from individual and regional perspectives. The UUFP more often sought equality of education for children and social integration in its choices of destinations. However, the distance was not a hindrance to intention to settle but played a substantial role in influencing it. We suggest optimizing the stock of the UUFP in large cities, improving public education services, and promoting remote urbanization. Likewise, industrial transfer and enhanced public resources may ease the pressure of large UUFP flows into large cities.

Snowpacks samples were colleted from two glaciers: Baishui No.1 glacier and Hailuogou No.1 glacier in June, 2006. The method of sea-salt ions tracer, correlation analysis and trend analysis were used in this research in order to confirm the source of main ions, it is indicated that Na+ is mainly from marine moisture and other ions mainly originate from land dust. The non-marine source percent of Cl^-, NO^-₃, SO^2-₄, K⁺, Ca²⁺ and Mg²⁺ is 52%, 99%, 100%, 98%, 99.9% and 83%, respectively, in Hailuogou No.1 glacier, while the corresponding value in Baishui No.1 glacier is 68%, 99%, 100%, 98%, 99% and 59%. The non-marine source of ions is from dust of Central Asia arid regions carried by westerly circulation and the plateau borne-areas with Qinghai-Tibet Plateau winter monsoon in two glacial areas. How-ever, the import of local dust in glacial area has made a great contribution to ions concentra-tion in Baishui No.1 glacier, which accounts for the reason why the ions concentration in Bai-shui No.1 glacier is much higher than that of Hailuogou No.1 glacier. It is obvious that the source of each ion is different between Hailuogou No.1 glacier and Baishui No.1 glacier. There are three reasons which can explain it: firstly, the difference in the internal environment of glacial area, such as lithology, mountain-valley wind system, topographical relief and so on; secondly, the influence exerted by ions elution in snowpacks section, and ions elution in Hailuogou No.1 glacier is very strong; and thirdly, the difference caused due to varying ions transporting styles, deposition modes, chemical characteristics and post-ions-deposition process.

Lakes in China have undergone considerable environmental changes during the past 50 years, e.g. lake level, water area changes, as did in the past several thousands years. The enhanced human activities, such as land reclamation, application of chemical fertilizer, land use and cover, irrigation and industrialization in the catchment etc., have played an im-portant role on the recent decades’ changes of these lakes, although constrained to a great extent by the natural impact. Comparative study on variations of lake volume (water level, depth and area) in the eastern and western lake regions of China during 1950–2000 indicated that, lake volume in the eastern region had approximately undergone a two-stage change, i.e. a dramatic decrease from the 1950s to 1970s, and a continuous increase between the 1980s and 1990s; while, in the western region, lake volume had been decreasing nearly all the time. Further studies on some typical lakes concluded that, climatic change was a primary factor for the variations of lake volume during the past 50 years, although human activities showed important effect.

Summer monsoons (South Asian monsoon, South China Sea monsoon and Sub-tropical monsoon) are prominent features of summertime climate over southern China. Dif-ferent monsoons carry different inflow moisture into China and control the temporal and spa-tial distributions of precipitation. Analyses of meteorological data, particularly wind, tempera-ture and pressure anomalies are traditional methods of characterizing moisture sources and transport patterns. Here, we try to utilize the evidence from stable isotopes signatures to trace summer monsoons over southern China. Based on seven CHNIP (Chinese Network of Iso-topes in Precipitation) observatory stations located in southern China, monthly composite precipitation samples have been collected and analyzed for the composition of δ¹⁸O during July, 2005. The results indicated that the spatial distributions of δ¹⁸O in precipitation could properly portray the moisture sources together with their transport pathways. Moreover, the amount effect, altitude effect, temperature effect and the correlation between δ¹⁸O vs. relative humidity were discussed.

By the Empirical Mode Decomposition method, we analyzed the observed monthly average temperature in more than 700 stations from 1951–2001 over China. Simultaneously, the temperature variability of each station is calculated by this method, and classification chart of long term trend and temperature variability distributing chart of China are obtained, supported by GIS, 1 km×1 km resolution. The results show that: in recent 50 years, the temperature has increased by more than 0.4℃/10a in most parts of northern China, while in Southwest China and the middle and lower Yangtze Valley, the increase is not significant. The areas with a negative temperature change rate are distributed sporadically in Southwest China. Meanwhile, the temperature data from 1881 to 2001 in nine study regions in China are also analyzed, indicating that in the past 100 years, the temperature has been increasing all the way in Northeast China, North China, South China, Northwest China and Xinjiang and declining in Southwest China. An inverse ‘V-shaped’ trend is also found in Central China. But in Tibet the change is less significant.

Based upon the 1970 aero-photo topographic map, and TM/ETM satellite images taken in 1991 and 2000, the authors artificially interpreted boundaries of lake and glaciers in Nam Co Catchment, and quantified lake-glacier area variations in different stages by “inte-grated method” with the support of GIS. Results show that from 1970 to 2000, lake area in-creased from 1942.34 km² to 1979.79 km² at a rate of 1.27 km²/a, while glacier area de-creased from 167.62 km² to 141.88 km² at a rate of 0.86 km²/a. The increasing rate of lake in 1991–2000 was 1.76 km²/a that was faster than 1.03 km²/a in 1970–1991, while in the same period of time, the shrinking rates of glaciers were 0.97 km²/a and 0.80 km²/a respectively. Important factors, relevant to lake and glacier response to the climate, such as air tempera-ture, precipitation, potential evapotranspiration and their values in warm and cold seasons, were discussed. The result suggests that temperature increasing is the main reason for the accelerated melting of glaciers. Lake expansion is mainly induced by the increase of the gla-cier melting water, increase of precipitation and obvious decrease of potential evapotranspi-ration. Precipitation, evaporation and their linkages with lake enlargement on regional scale need to be thoroughly studied under the background of global warming and glacier retreating.

With the rapid economic development during the last 30 years in China, more and more disparities have emerged among different regions. It has been one of the hot topics in the fields of physical geography and economic geography, and also has been the task for Chinese government to handle. Nevertheless, to quantitatively assess the impacts of physio-geographical patterns (PGP) on the regional development disparity has been ignored for a long time. In this paper, a quantitative method was adopted to assess the marginal ef-fects of the PGP on spatio-temporal disparity using the partial determination coefficients. The paper described the construction of the evaluation model step by step following its key scien-tific thinking. Total GDP, per capita GDP, primary industrial output value and secondary in-dustrial output value were employed in this study as the indicators to reflect the impacts of PGP on the regional development disparity. Based on the evaluation methods built by re-searchers, this study firstly analyzed the temporal impacts of the PGP on spatio-temporal disparity of the regional development in China during the past 50 years, and then explained the spatial differences at each development stage. The results show that the spatio-temporal disparity in China is highly related to the PGP, and that the marginal contribution rate could be employed as an effective way to quantitatively assess the impact of the PGP on spa-tio-temporal disparity of the regional development.

The Gurbantunggut Desert is the largest stable and semi-stable sand desert in China, yet few data exist on vegetation pattern and species-environment relationships for these diverse desert landscapes. The sand dunes of the survey area are mainly of the longitudinal form from north to south, but checkerboard-shaped and honeycomb-shaped forms are also present, with the height of 10–50 m. We measured vegetation and soil data on north–south transects and compared them with vegetation and soil data on east–west transects. Analysis revealed that the varying trend and strength of the species diversity, dominance and cover of the plant communities in the longitudinal and transverse directions across the landscape are significantly different. The results of CCA ordination show that the microhabitats of soil organic matter (OM), soil salts (TS), sorting index (σ), topsoil water-content (SM) and pH relate to the differences in vegetation observed as differences in species assemblage from salt-intolerant ephemerals, micro-subshrubs and subshrubs to salt-tolerant shrubs and micro-arbors. The terrain (alt.) and soil texture (the contents of Mz and φ1) affect the spatial differentiation of many species. However, this spatial differentiation is not so marked on transects running longitudinally with the landscape, in the same direction as the dunes. The species of the desert vegetation have formed three assemblages under the action of habitat gradients, relating to three sections running transversely across the landscape, at right angles to the direction of the dune crests. In the mid-east section of the study area the topography is higher, with sand-lands or dune-slopes with coarse particles. Here the dominant vegetation comprises shrubs and subshrubs of Seriphidium santolium and Ephedra distachya, with large numbers of ephemeral and ephemeroid plants of Senecio subdentatus, and Carex physodes in spring and summer. On the soil of the dune-slopes in the mid-west of the study area, with coarse particles and abundant TK, the plant assemblage of Haloxylon persicum, Soranthus meyeri and Agriophyllum squarrosum is developed. The species composition in the east marginal belt of the study area has similar characteristics to the mid-west section. There is no corresponding section in the north–south transects (except for the north and south margins). This is because the habitats of most plants are located in the middle of the microhabitat gradients in the north–south direction in the desert.

Supported by MSS images in the mid and late 1970s, TM images in the early 1990s and TM/ETM images in 2004, grassland degradation in the “Three-River Headwaters” region (TRH region) was interpreted through analysis on RS images in two time series, then the spatial and temporal characteristics of grassland degradation in the TRH region were ana-lyzed since the 1970s. The results showed that grassland degradation in the TRH region was a continuous change process which had large affected area and long time scale, and rapidly strengthen phenomenon did not exist in the 1990s as a whole. Grassland degradation pattern in the TRH region took shape initially in the mid and late 1970s. Since the 1970s, this deg-radation process has taken place continuously, obviously characterizing different rules in different regions. In humid and semi-humid meadow region, grassland firstly fragmentized, then vegetation coverage decreased continuously, and finally “black-soil-patch” degraded grassland was formed. But in semi-arid and arid steppe region, the vegetation coverage de-creased continuously, and finally desertification was formed. Because grassland degradation had obviously regional differences in the TRH region, it could be regionalized into 7 zones, and each zone had different characteristics in type, grade, scale and time process of grass-land degradation.

Anthropogenic greenhouse gases (GHG) emission and related global warming issues have been the focus of international communities for some time. The international communities have reached a consensus to reduce anthropogenic GHG emissions and restrain global warming. The quantitative assessment of anthropogenic GHG emissions is the scientific basis to find out the status of global GHG emission, identify the commitments of each country, and arrange the international efforts of GHG emission reduction. Currently the main assessment indicators for GHG emission include national indicator, per capita indicator, per GDP indicator, and international trade indicator etc. The introduction to the above indicators is put forward and their merits and demerits are analyzed. Based on the GHG emission data from the World Resource Institute (WRI), the US Energy Information Administration (EIA), and the Carbon Dioxide Information Analysis Center (CDIAC), the results of each indictor are calculated for the world, for the eight G8 industrialized countries (USA, UK, Canada, Japan, Germany, France, Italy and Russia), and the five major developing countries including China, Brazil, India, South Africa and Mexico. The paper points out that all these indicators have some limitations. The Indicator of Industrialized Accumulative Emission per Capita (IAEC) is put forward as the equitable indicator to evaluate the industrialized historical accumulative emission per capita of every country. IAEC indicator can reflect the economic achievement of GHG emission enjoyed by the current generations in every country and their commitments. The analysis of IAEC indicates that the historical accumulative emission per capita in industrialized countries such as UK and USA were typically higher than those of the world average and the developing countries. Emission indicator per capita per GDP, consumptive emission indicator and survival emission indicator are also put forward and discussed in the paper.

The summer day-by-day precipitation data of 97 meteorological stations on the Qinghai–Tibet Plateau from 1961 to 2004 were selected to analyze the temporal-spatial dis-tribution through accumulated variance, correlation analysis, regression analysis, empirical orthogonal function, power spectrum function and spatial analysis tools of GIS. The result showed that summer precipitation occupied a relatively high proportion in the area with less annual precipitation on the Plateau and the correlation between summer precipitation and annual precipitation was strong. The altitude of these stations and summer precipitation ten-dency presented stronger positive correlation below 2000 m, with correlation value up to 0.604 (α=0.01). The subtracting tendency values between 1961–1983 and 1984–2004 at five altitude ranges (2000–2500 m, 2500–3000 m, 3500–4000 m, 4000–4500 m and above 4500 m) were above zero and accounted for 71.4% of the total. Using empirical orthogonal function, summer precipitation could be roughly divided into three precipitation pattern fields: the Southeast Plateau Pattern Field, the Northeast Plateau Pattern field and the Three Rivers' Headstream Regions Pattern Field. The former two ones had a reverse value from the north to the south and opposite line was along 35°N. The potential cycles of the three pattern fields were 5.33a, 21.33a and 2.17a respectively, tested by the confidence probability of 90%. The station altitudes and summer precipitation potential cycles presented strong negative corre-lation in the stations above 4500 m, with correlation value of –0.626 (α=0.01). In Three Rivers Headstream Regions summer precipitation cycle decreased as the altitude rose in the sta-tions above 3500 m and increased as the altitude rose in those below 3500 m. The empirical orthogonal function analysis in June precipitation, July precipitation and August precipitation showed that the June precipitation pattern field was similar to the July’s, in which southern Plateau was positive and northern Plateau negative. But positive value area in July precipita-tion pattern field was obviously less than June’s. The August pattern field was totally opposite to June’s and July’s. The positive area in August pattern field jumped from the southern Pla-teau to the northern Plateau.

This paper studies the variation of runoff of Red River Basin and discusses the influence of “corridor-barrier” functions of valleys and mountains on variation of runoff by using GIS and statistic methods based on the monthly precipitation, temperature and evaporation data from 1960 to 2000 at 32 meteorological stations in Red River Basin, and the annual runoff data of Yuanjiang River, Lixian River and Panlong River from 1956 to 2000. The results show out: (1) Under the effect of “corridor-barrier” functions of valleys and mountains in Red River Basin, the patterns of annual precipitation and runoff depth distribution in spatial change a NW–SE direction, which is similar with the trend of the Red River valley and Ailao mountains. (2) In the long temporal scale averaged over years, the most obvious effects of the “corridor-barrier” functions is on runoff variation, and the second is on the precipitation, but not obvious on the temperature. (3) Under the superposed effect of climate changes and the “corridor-barrier” functions of valleys and mountains in Red River Basin, the difference of runoff variation is obvious in the east–west direction: the runoff variation of Yuanjiang River along the Red River Fault present an ascending trend, but the Lixian River on the west side of the Fault and the Panlong River on the east present a descending trend; the annual runoff in Yuanjiang River and Panlong River had a quasi-5a periods, and Panlong River had a quasi-8a periods; the runoff variation are quite inconsistent in different periods among the three river basins.

This paper brought out a new idea on the retrieval of suspended sediment concentration, which uses both the water-leaving radiance from remote sensing data and the grain size of the suspended sediment. A principal component model and a neural network model based on those two parameters were constructed. The analyzing results indicate that testing errors of the models using the two parameters are 0.256 and 0.244, while the errors using only water-leaving radiance are 0.384 and 0.390. The stability of the models with grain size parameter is also better than the one without grain size. This research proved that it is necessary to introduce the grain size parameter into suspended sediment concentration retrieval models in order to improve the retrieval precision of these models.

Based on four phases of TM images acquired in 1990, 1995, 2000 and 2005, this paper took Kitakyushu in Japan as a case study to analyze spatial change of land use landscape and corresponding effects on environmental issues guided by landscape ecology theory in virtue of combining technology of Remote Sensing with GIS. Firstly, land use types were divided into 6 classes (farmland, mountain, forestland, water body, urban land and unused land) according to national classification standard of land use, comprehensible ability of TM image and purpose of this study. Secondly, following the theory of landscape ecology analysis, 11 typical landscape indices were abstracted to evaluate the environmental effects and spatial feature changes of land use. Research results indicated that land use has grown more and more diversified and unbalanced, human activities have disturbed the landscape more seriously. Finally, transfer matrix of Markov was applied to forecast change process of land use in the future different periods, and then potential land use changes were also simulated from 2010 to 2050. Results showed that conversion tendency for all types of land use in Kitakyushu into urban construction land were enhanced. The study was anticipated to help local authorities better understand and address a complex land use system, and develop improved land use management strategies that could better balance urban expansion and ecological conservation.

Land use change plays an important part in the studies of global environmental change and regional sustainable development. The change of soil quality can particularly reflect the impacts of human socio-economic activities on environment. Taking the coastal plain of south Hangzhou Bay as a study case, we analyzed the effects of land use changes on organic matter (OM), total nitrogen (TN), total phosphorus (TP), available phosphorus (AP), available potassium (AK), total salinity (TS), pH value in soil genetic layers, and assessed soil quality change related to different land use types from 1982 to 2003. The results show that: (1) The general change tendency of soil quality in the coastal plain of south Hangzhou Bay declined obviously in A layer and slightly rise in B (or P) layer and C (or W) layer. The contents of TP decreased generally in all soil genetic layers, but the variety difference of other soil quality indices was relatively great. (2) The change of soil quality in the areas where land use changed is far more remarkable than that with land use unchanged. The value of quality variety is A layer >B (or P) layer >C (or W) layer. (3) The changes of soil tillage, cultivation, fertilization, irrigation and drainage activities related to land use may make some soil-forming processes disappeared and bring in other new processes which will affect the soil quality and soil genetic layers directly.

Based on dynastic period division and AMS¹⁴C dating performed on the sedimen-tary layers at Zhongba and Yuxi sites, and also the analysis of Na, Ca and Mg of 201 sedi-mentary samples from Zhongba site and that of Ca and Na in 47 sedimentary samples from Yuxi by using an inductively coupled plasma–mass spectrometry (ICP), we found that there were 35 time periods when the contents of Ca and Na were reversely correlated, i.e. when-ever the content of Ca was the highest, the content of Na was the lowest, and vice versa. Among them, there were 21 time periods when the content of Ca was the highest, and Na was the lowest, indicating that there were about 21 prosperous periods of ancient salt pro-duction at Zhongba site since 3000BC. Other 14 time periods with the peak values of Na while the low values of Ca indicate 14 declined periods of salt production at Zhongba site since 3000BC. The conclusion obtained from the reverse relationship between Ca and Na contents in this paper is consistent with that “the salt production at Zhongba site started in the new stone age, developed in the Xia and Shang dynasties, reached at the heyday in periods from the Western Zhou to the Han Dynasties, maintained stable to develop in the Tang and the Song dynasties, and gradually declined after the Song Dynasty because the sea salt were conveyed into Sichuan region, however, still had production in the 1970s–1980s”, educed from archeological exploration. All the above mentioned results indicate that there is a re-verse relationship obviously between the contents of Na and Ca in sediments at Zhongba site for ancient salt production, which can

This study examined livelihood diversification and cropland use pattern in Keerma village, located in Jinchuan County, eastern Tibetan Plateau. Through stratified random sampling survey, participatory rural appraisal, investigation of households’ plots and statistical methods, 63 households and 272 cropland plots were systemically investigated and sampled. The results show: (1) Different types of household have variety livelihood strategies, portfolio and income. Livelihood diversification and introducing and expanding off-farm activities can be the future trend, whereas, adverse natural environment, socio-economic conditions and peasants’ capabilities together affect sustainable livelihood and land use. (2) Each livelihood strategy has its own impact on land use, mainly affecting land use type and land use intensification level. (3) Diversification into off-farm activities could be the key of building sustainable livelihood and the essential approach of realizing sustainable land use in the region.