The Holocene Megathermal is divided into early, middle and late periods, each having different impacts on the Neolithic cultures due to their different climate changing trends. This study is based on a comparative analysis of the environmental evolution information recorded in the Qinghai Lake, the western edge of the Loess Plateau and Zoige and the spatial distribution of Neolithic sites of the Gansu-Qinghai region. Results show that the early and middle periods towards warm and humid promoted the development of Neolithic cultures with agriculture as the main sector in the Gansu-Qinghai region, furthermore a heyday of Yangshao Culture prosperity emerged. The Holocene entered the late period after the cold climate event at 5.9 ka BP in the Gansu-Qinghai region. Later the climate began to turn cold. However, at the 5.8–4.2 ka BP a relatively stable warm and humid climate created the conditions for the development of Majiayao Culture of the Neolithic Age in this region, thus the distribution of its cultural heritage sites expanded towards high altitudes and high latitudes. From 4.2 ka BP onwards, the climate became cold and dry, which had a significant influence on the Neolithic cultures of the Gansu-Qinghai region, leading to a dramatic change in the cultural characters and spatial distribution of Qijia Culture around 4.2 ka BP. After a nearly 300 years of cold and dry period, the unified Neolithic farming culture completely collapsed. Afterwards an industrial division of animal husbandry and farming and regional multiple cultures formed, and ultimately led to the end of primitive society and the starting of a civilized society.

The application of dams built upstream will change the input conditions, including water and sediment, of downstream fluvial system, and destroy previous dynamic quasi-equilibrium reached by channel streamflow, so indispensable adjustments are necessary for downstream channel to adapt to the new water and sediment supply, leading the fluvial system to restore its previous equilibrium or reach a new equilibrium. Using about 50-year-long hydrological, sedimentary and cross-sectional data, temporal response processes of Toudaoguai cross-section located in the upper Yellow River to the operation of reservoirs built upstream are analyzed. The results show that the Toudaoguai cross-section change was influenced strongly by upstream reservoir operation and downstream channel bed armoring thereafter occurred gradually and extended to the reach below Sanhuhekou gauging station. Besides, median diameter of suspended sediment load experienced a three-stage change that is characterized by an increase at first, then a decrease and an increase again finally, which reflects the process of channel bed armoring that began at Qingtongxia reservoir and then gradually developed downstream to the reach below Sanhuhekou cross-section. Since the joint operation strategy of Longyangxia, Liujiaxia and Qingtongxia reservoirs was introduced in 1986, the three-stage change trend has become less evident than that in the time period between 1969 and 1986 when only Qingtongxia and Liujiaxia reservoirs were put into operation alone. In addition, since 1987, the extent of lateral migration and thalweg elevation change at Toudaoguai cross-section has reduced dramatically, cross-sectional profile and location tended to be stable, which is beneficial to the normal living for local people.

We analyzed and estimated the distribution and reserves of soil organic carbon under nine different vegetation conditions including alpine meadow, meadow steppe, typical steppe, desert steppe, and temperate coniferous forest and so on, in the Ili River valley, Xinjiang according to data from field investigations and laboratory analyses in 2008 and 2009. The study results show that the soil organic carbon content in the Ili River valley varies with the type of vegetation. In the 0–50 cm soil horizon, the soil organic carbon content is the highest under the vegetation types of alpine meadow and meadow steppe, slightly lower under temperate coniferous forest and typical steppe, and the lowest under the intrazonal vegetation and desert vegetation types. The soil organic carbon content shows basically a tendency to decrease as soil depth increases under various vegetation types except in the case of the intrazonal vegetation. Similarly, the soil organic carbon density is the highest and varies little under the vegetation types of alpine meadow, meadow steppe and temperate coniferous forest, and is the lowest under the desert vegetation type. Both the soil organic carbon content and density in the topsoil of meadows in the Ili River valley are high, so protecting meadows in the Ili River valley, and especially their topsoil, should be a priority so that the potential of change in soil organic carbon in the shallow soil horizon is reduced, and this means maintenance of the stability of the soil carbon pool.

Based on the measured hydrological data from 1951 to 2008, the chain hydrological effect between Jingjiang River and Dongting Lake is analyzed by comparative method after the Three Gorges Project operation. The result indicates that 1) the scouring amount in Jingjiang River made up 78.9% of the total from Yichang to Chenglingji, and its average scouring intensity was higher than the latter; 2) the water and sand diversion rates at the three outlets of the Jingjiang River were reduced by 2.33% and 2.78% separately; 3) the proportion of multi-year average runoff and sediment through the three outlets in the total into the Dongting Lake decreased by 7.7% and 24.4% respectively; 4) in Dongting Lake, the speed of sediment accumulation was lowered by 26.7%, in flood season, the runoff amount was 20.2% less than the multi-year average value, leading to seasonal scarcity of water year by year. The former prolonged the lake life, while the latter induced droughts in summer and fall in successive years, shortage of drinking and industrial water, shipping insecurity, as well as ecological problems such as decrease of birds and quick increase of Microtus fortis; 5) The multi-year average values of sediment and flood transporting capacity at the lake outlet were respectively increased by 26.6% and 3.7%, the embankments were protected effectively. Then, to adapt to the new change of the river-lake relation, some suggestions were put forward, such as optimizing further operation program of the Three Gorges Reservoir, reexamining the idea of river and lake regulation, and maintaining connection of the river and the lake.

This paper mainly analyzes the geomorphological changes of the tidal deposition in the Liaohe Estuary based on the multi-year bathymetric charts in 1990, 1996, 2002 and 2005 and Landsat TM images in 1987, 1994, 2002 and 2005. Evolution of the tidal depositional system during the past 20 years in the Liaohe River was studied on the basis of 50 boreholes drilling and 30 km shallow stratigraphic exploration from 2002 to 2005. The main tidal depositional body of the modern Liaohe River delta is located in the Shuangtaizihe Estuary. The stratum within the depth of 10 m includes tidal bank facies, tidal channel facies and neritic facies with paleo-delta facies underlying them. The sediments of tidal bank facies are mainly composed of sand and silt with siltation load and suspended load of about 50% respectively in proportion. The sediment of tidal channel facies and neritic facies is composed of clayey silt and silty clay which belongs to suspended load. The study area was a small bay between the old Daliaohe River, the old Dalinghe River and the Raoyanghe River complex delta since the Holocene to 1896. Many tidal banks formed and expanded rapidly after the Shuangtaizihe River was excavated by labor in 1896. The runoff and sediment discharge have decreased since the construction of brake at the Shuangtaizihe River in 1958.The Shuangtaizihe Estuary is in the state of deposition as a whole whose tidal bank is increasing and expanding southward, westward and northward. The maximum expansion speed is 87 to 683 m/a and the mean depositional rate is 0.189 m/a. Erosion occurred in some part of tidal bank with average erosional rate of 0.122 m/a. The tidal channel was filled up with sediment at a migration speed of 48–200 m/a. Geomorphologic changes have happened under the combined influences of runoff, ocean dynamics and human activities. The main source of sediment changes from river sediment to sediment driven by tidal current and longshore current.

The Loess positive and negative terrains (P–N terrains), which are widely distributed on the Loess Plateau, are discussed for the first time by introducing its characteristic, demarcation as well as extraction method from high-resolution Digital Elevation Models. Using 5 m-resolution DEMs as original test data, P–N terrains of 48 geomorphological units in different parts of Shaanxi Loess Plateau are extracted accurately. Then six indicators for depicting the geomorphologic landscape and spatial configuration characteristic of P–N terrains are proposed. The spatial distribution rules of these indicators and the relationship between the P–N terrains and Loess relief are discussed for further understanding of Loess landforms. Finally, with the integration of P–N terrains and traditional terrain indices, a series of un-supervised classification methods are applied to make a proper landform classification in northern Shaanxi. Results show that P–N terrains are an effect clue to reveal energy and substance distribution rules on the Loess Plateau. A continuous change of P–N terrains from south to north in Shaanxi Loess Plateau shows an obvious spatial difference of Loess landforms and the positive terrain area only accounted for 60.5% in this region. The P–N terrains participant landform classification method increases validity of the result, especially in the Loess tableland, Loess tableland-ridge and the Loess low-hill area. This research is significant on the study of Loess landforms with the Digital Terrains Analysis methods.

Seven cores were collected from different sediment zones of tidal flats at Xinyanggang in north Jiangsu province in August 2007. Sediment grain-size distribution and radioisotopes of 137Cs and 210Pb analysis were carried out for these cores. Sediment rates of the cores and radioisotopes distribution in surface sediment in different zones of the tidal flat were calculated from the 137Cs and 210Pb activities in sediments cores. The results indicated that each tidal zone had experienced different evolution phases, hydrological dynamics in the tidal flats made the grain-size of the surface sediment change gradually. 137Cs and 210Pb activities on the superficial layer of the cores varied spatially and the reason was discussed. On tidal flats, the fluctuation of 137Cs and 210Pb activities in the cores reflected the special sedimentary characteristics. Vegetation affects the grain-size distribution and the vertical profiles of 137Cs and 210Pb in the upper depths. 137Cs and 210Pb chronology got the comparable average sediment rates on the tidal flat. The characteristics of 137Cs and 210Pb in the cores reflected various depositional dynamical environments in different tidal zones and gave information on the different evolvement phases of the tidal zones. Based on the information of grain-size distribution, texture of the cores, sediment rates and topography, the evolution lines of the tidal flat were reconstructed.

The environmental quality of heavy metals (Pb, Cd, Cr, As, Hg) in agricultural surface soil of Chongming Island was assessed by national, local and professional standards based on a large scale investigation, in which 28 samples from vegetable plots, 65 samples from paddy fields and 9 samples from watermelon fields were collected from whole island area. Results showed that the average concentration of Pb, Cd, Cr, As and Hg was 21.6 mg·kg^-1 , 0.176 mg·kg^-1, 69.4 mg·kg^-1, 9.209 mg·kg^-1 and 0.128 mg·kg^-1, respectively. Compared with the background value of Shanghai City soil, except for Pb and Cr, all the other heavy metals average concentrations in Chongming Island agricultural surface soil exceeded their corresponding natural-background values. The concentrations of Cd, As and Hg were 33.0%, 1.2% and 26.3% higher than the background value of Shanghai City, respectively. In addition, inverse distance interpolation (IDW) tool of GIS was also applied to study the spatial variation of heavy metals. The results indicated that most of agricultural soil quality was good, and the ratio of ecological, good soil, certified soil and disqualified soil were 1.26%, 97.1%, 1.47% and 0.12%, respectively. About 10.1%, 85.7%, 27.0%, 55.4% and 55.2% soil samples exceeded the Pb, Cd, Cr, As and Hg background value of Shanghai City, respectively. Among these three land use type soils, vegetable soil was most seriously polluted by heavy metals, which is probably related to the over-application of pesticides. The annual deposition fluxes of Pb, Cd, As and Hg were 7736 μg·m^-2·a^-1, 208 μg·m^-2·a^-1, 2238 μg·m^-2·a^-1 and 52.8 μg·m^-2·a^-1, respectively. Crop straw burning was the important source of heavy metals of atmospheric deposition, and atmospheric deposition contributed a lot to heavy metals in agricultural soil in Chongming Island.

Geomorphologic maps are one of the most fundamental materials of the natural environment. They have been widely used in scientific research, resource exploration and extraction, education and military affairs etc. An editorial committee was established in 2001 to collect materials for researching and compiling a set of new 1:1,000,000 geomorphologic atlas of China. A digital geomorphologic database was created with visual interpretation from Landsat TM/ETM imageries and SRTM-DEM etc. The atlas compiled from the database was finished. The main characteristics of the atlas are as follows: Firstly, Landsat TM/ETM imageries, published geomorphologic maps or sketches, geographical base maps, digital geological maps, and other thematic maps were collected, which were uniformly geometrically rectified, clipped into uniform sheets, and stored in the foundation database. Secondly, based on the legends of 15 sheets 1:1,000,000 maps published in the 1980s, a geomorphologic classification system was built by combining morphology and genesis types. The system comprised seven hierarchical layers: basic morphology, genesis, sub-genesis, morphology, micro-morphology, slope and aspect, material composition and lithology. These layers were stored in the database during visual image interpretation. About 2000 kinds of morpho- genesis and 300 kinds of morpho-structure were interpreted. Thirdly, the legend system was built, which included color, symbol bases and note bases etc., compilation standards and procedures were developed, 74 sheets of 1:1,000,000 covering all land and sea territories of China were compiled, the 1:1,000,000 geomorphologic atlas of the People’s Republic of China was finished and published. The atlas will fill the blanks in national basic scale thematic maps, and the geomorphologic database could be applied widely in many fields in the future.

Spatial relations, reflecting the complex association between geographical phenomena and environments, are very important in the solution of geographical issues. Different spatial relations can be expressed by indicators which are useful for the analysis of geographical issues. Urbanization, an important geographical issue, is considered in this paper. The spatial relationship indicators concerning urbanization are expressed with a decision table. Thereafter, the spatial relationship indicator rules are extracted based on the application of rough set theory. The extraction process of spatial relationship indicator rules is illustrated with data from the urban and rural areas of Shenzhen and Hong Kong, located in the Pearl River Delta. Land use vector data of 1995 and 2000 are used. The extracted spatial relationship indicator rules of 1995 are used to identify the urban and rural areas in Zhongshan, Zhuhai and Macao. The identification accuracy is approximately 96.3%. Similar procedures are used to extract the spatial relationship indicator rules of 2000 for the urban and rural areas in Zhongshan, Zhuhai and Macao. An identification accuracy of about 83.6% is obtained.

Afforestation in China’s subtropics plays an important role in sequestering CO₂ from the atmosphere and in storage of soil carbon (C). Compared with natural forests, plantation forests have lower soil organic carbon (SOC) content and great potential to store more C. To better evaluate the effects of afforestation on soil C turnover, we investigated SOC and its stable C isotope (δ¹³C) composition in three planted forests at Qianyanzhou Ecological Experimental Station in southern China. Litter and soil samples were collected and analyzed for total organic C, δ¹³C and total nitrogen. Similarly to the vertical distribution of SOC in natural forests, SOC concentrations decrease exponentially with depth. The land cover type (grassland) before plantation had a significant influence on the vertical distribution of SOC. The SOC δ¹³C composition of the upper soil layer of two plantation forests has been mainly affected by the grass biomass ¹³C composition. Soil profiles with a change in photosynthetic pathway had a more complex ¹³C isotope composition distribution. During the 20 years after plantation establishment, the soil organic matter sources influenced both the δ¹³C distribution with depth, and C replacement. The upper soil layer SOC turnover in masson pine (a mean 34% of replacement in the 10 cm after 20 years) was more than twice as fast as that of slash pine (16% of replacement) under subtropical conditions. The results demonstrate that masson pine and slash pine plantations cannot rapidly sequester SOC into long-term storage pools in subtropical China.

We analyzed the Normalized Difference Vegetation Index (NDVI) from satellite images and precipitation data from meteorological stations from 1998 to 2007 in the Dongting Lake wetland watershed to better understand the eco-hydrological effect of atmospheric precipitation and its relationship with vegetation. First, we analyzed its general spatio-temporal distribution using its mean, standard deviation and linear trend. Then, we used the Empirical Orthogonal Functions (EOF) method to decompose the NDVI and precipitation data into spatial and temporal modes. We selected four leading modes based on North and Scree test rules and analyzed the synchronous seasonal and inter-annual variability between the vegetation index and precipitation, distinguishing time-lagged correlations between EOF modes with the correlative degree analysis method. According to our detailed analyses, the vegetation index and precipitation exhibit a prominent correlation in spatial distribution and seasonal variation. At the 90% confidence level, the time lag is around 110 to 140 days, which matches well with the seasonal variation.

Based on data collected over five years of monitoring the Lower Tarim River, we analyzed the variability of soil moisture content (SMC) and the relationship between SMC, groundwater table depth (GWD) and vegetation by using the methods of coefficient of variation (Cv), Pearson correlation and regression. The results of the variability of SMC indicate that it rose with increase in depth of soil layer – SMC in the soil layer of 0–60 cm was relatively small compared to SMC in the soil layer of 100–260 cm which showed a significant increase in variability. SMC and GWD before and after ecological water diversions exhibited significant differences at the site of the Yingsu transect and its vicinity of the watercourse, especially SMC in the soil layer of 100–260 cm increased significantly with a significant rise of GWD and reached maximum values at a GWD of about 4 m. Plant coverage and species diversity significantly improved with increases in SMC in the soil layer of 100–260 cm, both of them approached the maximum values and 92.3% of major plant species were able to grow when SMC was > 10%. To restore the ecosystem of desert riparian forest along the Lower Tarim River, the GWD must be maintained at < 4 m in the vicinity of the watercourse and at about 4 m for the rest of this arid region.

The spatial distribution and seasonal variation of the tide-induced Lagrangian Residual Circulations (LRC hereafter), wind-driven LRC, and the coupling dynamic characteristics were simulated using ECOM, given the Hellerman and Rosenstein global monthly-mean wind stresses. The results showed that the tide-induced LRC of the harmonic constituent m² bears an identical pattern in four seasons in the Bohai Sea: the surface one is weak with random directions; however, there exist a southeast current from the Bohai Strait to the Laizhou bay, and a weakly anticlockwise gyre in the south of the Bohai Strait for the bottom layer LRC. The magnitude of bottom layer tide-induced LRC is larger than the surface one, and moreover, it contributes significantly to the whole LRC in the Bohai Sea. Unlike the identical structure of the tide-induced LRC, the wind driven LRC varies seasonally under the prevailing monsoon. It forms a distinct gyre under the summer and winter monsoons in July and January respectively, but it seems weak and non-directional in April and September.

Given the great number of studies focusing on the temporal interaction between economic and environmental subsystems, it is useful to perform a quantitative spatial assessment of these subsystems. In this paper, comprehensive assessment indicators for regional economic development and environmental pollution subsystems are constructed. Then, the degree of coupling and coordination of the regional economy-environment system is calculated for 350 prefectural units in China. It is found that the economic development and environmental pollution in most prefectural units is still at a low level of coupling and coordination. According to the coupling and coordination values, the Chinese territory can be divided into four types of area: economy-environment harmonious area, economy-environment gearing area, economy-environment rivaling area and low coupling degree of economy-environment area. Based on a structural analysis of the industrial sector in the four types of areas, there is a spatial relationship between the regional industrial sector structure and the coupling-coordination level. In the economy-environment harmonious area, the sectors of manufacturing of high-technology and high value-added products, such as communications, computer and electronic equipment, transport equipment and electrical machinery, account for a large proportion of the value of local industrial output. The industrial value of the economy-environment gearing area is concentrated on the manufacturing of machinery and equipment, and contains a few polluting sectors such as ferrous and non-ferrous metallurgy, chemical manufacturing and electricity generation. The economy-environment rivaling area is the type of area where polluting sectors concentrate, such as iron and steel, petrifaction, coal mining, building materials and electricity generation. In the low coupling degree of economy-environment area, its industry is concentrated on the production and processing of primary products.

Choosing site area, cultural layer thickness, significant relics and significant remains as the variables, we applied cluster analysis to the ancient settlements of four cultural periods, respectively, which were Peiligang, Yangshao, Longshan and Xiashang, in 9000-3000 a BP, around Songshan Mountain. Through application of the SOFM (self-organizing feature map) networks, every type of ancient settlements was classified into different size-grades. By this means, the Peiligang settlements were divided into two grades, Yangshao and Longshan settlements were divided into three grades, respectively, and Xiashang settlements were divided into four grades. The results suggested that the size-grade diversity of ancient settlements was not significant during the Peiligang period in this area. Around the middle-late Yangshao period (5000 a BP), the size-grade diversity of ancient settlements began to appear, a process that continued during the Longshan period and finally matured in the Xiashang period. Moreover, the results reflected the regional differences in cultural characteristics in a particular period, which were mainly represented in that there were three Peiligang cultural systems distributed in different areas. Such differences also existed in the spatial distributive characteristics between the Xia and Shang cultures. Based on the size-grade study of ancient settlements in the Circum-Songshan area, it was found that the SOFM networks method was very suitable for size-grade classification of ancient settlements, since, using this method, adjacent cells would compete and learn from each other, a benefit that reduced the effect on classification by the inaccuracy of site acreages.

The 13 provinces (autonomous regions and municipalities) in northern China are located in latitude 31°–54°N and longitude 73°–136°E including Beijing, Tianjin, Hebei, Shanxi, Inner Mongolia, Jilin, Liaoning, Heilongjiang, Shaanxi, Gansu, Ningxia, Qinghai, and Xinjiang, where environments are fragile. In recent years, the eco-environmental problems such as vegetation destruction, desertification and soil erosion etc. become serious because of climate change and unreasonable human activities. In this paper, landscape pattern and its evolution in northern China from 1989 to 2003 was investigated by the combined use of RS and GIS based on the basic theory and method of landscape ecology. Land use/cover maps of the study area in 1989, 1999 and 2003 were produced by using 1 km monthly NOAA Ad-vanced Very High Resolution Radiometer (AVHRR) and SPOT/VGT Normalized Difference Vegetation Index (NDVI) dataset from national climate bureau of China which were geo-registered to Lambert azimuthal equal-area map projection and were used in the paper. Landscape evolution in the area over the study period was investigated by two methods: (a) the changes of various landscape metrics were analyzed using the landscape structure analysis program FRAGSTATS; (b) the transition matrix of landscape patch types was cal-culated with the help of the RS and GIS software. The results showed that from 1989 to 2003, the landscape within the study area had undertaken a complicated evolution in landscape structure and composition. The diversity index and evenness index increased during the pe-riod, which means that the landscape pattern tended to be diversified and even. The fragmentation index of grassland, forestland and water areas also increased significantly. This showed that the distribution and structure of forestland, grassland and water areas had been changed greatly during the period, especially grassland which became more and more fragmentized, and its fragmentation index increased from 19.23% to 88.72%. The transitions of the landscape types were mainly shown by the changes among forestland, grassland and farmland, and grassland changing into unable land. Over the study period, grassland and water areas had decreased remarkably, accounting for 15% and 37% from 1989 to 1999 and 24.79% and 49.25% from 1999 to 2003 respectively. The grassland and water resources play an important role in the eco-environment and economic development of the region. So, they must be protected carefully. According to the analysis, we can conclude that the eco-environment in the study area is obviously degenerated due to unreasonable human activities and climate changes and some measures should be taken to combat the environ-mental degradation.

The suitability evaluation of population and settlements spatial layout in the mountainous areas is an important basis on which the scale of population and settlement after Wenchuan Earthquake is determined. Based on the statistical data of field research, this paper chooses 1264 towns in 51 counties as the scope of evaluation, selects eight indices in the evaluation index system which includes post-disaster population scale, population density, urbanization rate, the percentage of migrant workers, death rate by earthquake, the percentage of minorities, elevation-slope integrated terrain and comprehensive geological condition. Besides, this paper uses AHP supported by entropy technique and fuzzy membership function model to calculate the suitability evaluation index and then divides the disaster areas into five types: highly suitable area (area accounted for 11.03%), relatively highly suitable area (15.29%), moderately suitable area (29%), less suitable area (30.08%) and unsuitable area (14.6%). According to the result of suitability evaluation, this paper puts forward several suggestions for the reconstruction as follows: the urban system and the building of new countryside should be guided by the suitability evaluation subareas; post-earthquake reconstruction avoids zones near Longmenshan fracture and high-mountain gorge areas as far as possible; the scale of population and settlement should not exceed the capacity of resources and environment; population should be resettled as close as possible by considering adequately the heterogenicity and homogeneity of regional nationality culture characteristics; densely resettle the people at plains and hilly areas; encourage the migrant workers settle in the working place with their families voluntarily; and urban system reconstruction such as industry layout and important projects of lifeline should be guided by the spatial layout suitability evaluation.

This study analyses spatial variability and trends in annual and monthly precipitation (amount and concentration) based on data from 42 stations in mainland Portugal during the period 1960-2011. Relationships between certain geographic variables (elevation, latitude and longitude) and precipitation variability were also determined in order to check for specific dependencies and spatial patterns in precipitation distribution, concentration and changing trends. Trends and relationships have been analysed using both parametric and non-parametric tests. The results showed that annual precipitation had decreased in all stations and that this trend is statistically significant for most of the time series (70% of the stations showed negative trends with at least a 0.1 significance level). The Annual Precipitation Concentration Index revealed an opposite behaviour pattern, suggesting that even though the annual trend for precipitation amount was negative overall, more than half of the udometric stations registered a more marked seasonality for precipitation during the period 1960-2011. However, only one station showed statistical significant time trend. Regarding the influence of geographical features, latitude is the most important variable, governing spatial distribution and variations in annual precipitation as well as its intra-annual changeability. These important changes in precipitation, involving both amount and concentration, may have severe consequences for ecosystems and societies.

Proxy records of the oxygen isotopic composition of meteorological precipitation (δ¹⁸O_p) preserved in archives such as ice cores, lacustrine carbonates and stalagmite calcite are important for paleoclimatic studies. Therefore, knowledge of the variations and controlling mechanisms of modern δ¹⁸O_p on different time scales is necessary. Here, we investigate the linear correlations between δ¹⁸O_p and corresponding temperature and precipitation on monthly and inter-annual timescales, using data from the Urumqi (1986-2003) and Hotan stations of the Global Network of Isotopes in Precipitation (GNIP), and δ¹⁸O data from 4 ice cores in the adjacent Tianshan Mountains. Consistent with previous reported results, modern δ¹⁸O_p variations on a seasonal time scale in the Tianshan region are mainly controlled by a ‘temperature effect’ (indicated by a significant positive correlation between δ¹⁸O_p and temperature), with more positive δ¹⁸O_p values occurring in summer. However, on an inter-annual timescale, there is a weak inverse correlation between weighted average annual δ¹⁸O_p and annual average temperature at Urumqi station. This finding is supported by the inversely varying trends of δ¹⁸O data from 4 ice cores in the central and eastern Tianshan Mountains compared to annual average temperatures in the same region during the past 40-50 years. The data from Urumqi station and the 4 ice cores demonstrate that there is inverse correlation between δ¹⁸O_p and temperature on inter-annual to decadal time scales. Analysis of water vapor sources and pathways for the warm year of 1997 and the cold year of 1988 reveal that relatively more water vapor for the Tianshan region was derived from long-distance transport from high-latitude sources than during the warm year of 1997; and that more water vapor was transported from more proximal sources from mid- to low-latitude areas during the cold year of 1988. In addition, the δ¹⁸O_p values are more negative in the high latitude areas than those in mid- to low-latitude areas in the Eurasian continent at the upper wind direction of Tianshan Mountains region, according to the weighted averaged warm season (May to September) δ¹⁸O_p values for 14 GNIP stations in the years 1997 and 1988. Due to the distribution of δ¹⁸O_p within the Eurasian continent, the relative shift of water vapor sources between warm and cold years convincingly explains the observed variations of δ¹⁸O_p in the Tianshan Mountains region. Therefore, we conclude that variations in δ¹⁸O_p in this region are mainly controlled by changes in water vapor sources which are ultimately caused by northward and southward shifts in the Westerly circulation.

Land function change has been the focus of scientific research and policy making worldwide. Agricultural development and land use demand at present in China shared common characteristics with the countries such as Japan, South Korea, USA, and European developed countries, which have undergone cultivated land function transition. Whether cultivated land function transition occurred is of significance for land change science and cultivated land protection in China. However, there has been no explicit methodology for cultivated land function change research. This paper firstly presents a methodology by integrating policy development analysis based on the normative connotation of cultivated land function or termed cultivated land function demand and quantitative assessment based on the positive connotation of cultivated land function or termed cultivated land function supply. Then, cultivated land function transition is diagnosed by analyzing cultivated land function change in 1949-2012. Results show that cultivated land function transition overall occurred in 2006. Specifically, the normative cultivated land function or cultivated land function demand fragmented into seven types in 1985 and upgraded in 2004. Total value of the positive cultivated land function or cultivated land function supply turned to rise with an increase from 2.40 to 2.45 as the coefficients of variability (CV) of the value of the seven functions decreased from 2.94 to 2.29 in 2006-2012. The two-year gap between these two aspects of transition mainly resulted from the time lag effects of policy implementation. In the process of the transition, co-ordination and malposition of supply and demand of cultivated land function coexisted with supply lag and function morphology distortion. Considering the transition experiences in the developed countries mentioned above, suggestions on multifunctional cultivated land management are proposed. Moreover, route of land use transition research is discussed.

The Conversion of Land Use and its Effects at Small regional extent (CLUE-S) model is a widely used method to simulate land use change. An ordinary logistic regression model was integrated into the CLUE-S model to identify explanatory variables without considering the spatial autocorrelation effect. Using image-derived maps of the Changsha- Zhuzhou-Xiangtan urban agglomeration, the CLUE-S model was integrated with the ordinary logistic regression and autologistic regression models in this paper to simulate land use change in 2000, 2005 and 2009 based on an observation map from 1995. Significant positive spatial autocorrelation was detected in residuals of ordinary logistic models. Some variables that were much more significant than they should be were selected. Autologistic regression models, which used autocovariate incorporation, were better able to identify driving factors. The Receiver Operating Characteristic Curve (ROC) values of autologistic regression models were larger than 0.8 and the pseudo R² values were improved, compared with results of logistic regression model. By overlapping the observation maps, the Kappa values of the ordinary logistic regression model (OL)-CLUE-S and autologistic regression model (AL)-CLUE-S models were larger than 0.75. The results showed that the simulation results were indeed accurate. The Kappa fuzzy (Kfuzzy) values of the AL-CLUE-S models (0.780, 0.773, 0.606) were larger than the values of the OL-CLUE-S models (0.759, 0.760, 0.599) during the three periods. The AL-CLUE-S models performed better than the OL-CLUE-S models in the simulation of land use change. The results showed that it is reasonable to integrate autocovariates into CLUE-S models. However, the Kfuzzy values decreased with prolonged duration of simulation and the maximum range of time was not discussed in this paper.

Based on remote sensing data of the Yangtze River Delta (YRD) in the years of 1991, 2001 and 2008, the paper built an index system of land use potential restraint factors in YRD, according to geological condition, terrain condition, water area, natural reserve area and basic farmland, and evaluated construction land potential based on the platform of GIS spatial analysis model. The results showed that: (1) the construction land increased rapidly since 1991 and reached 24,951.21 km² in 2008, or 21.27% of the total area. Among all the cities in the YRD, Shanghai took the greatest percentage, followed by Jiangsu and Zhejiang. Spatially, areas where government departments are located became the growth center of construction land. Prefecture-level cities were the fastest growth region and the changing trend showed circle layered characteristics and significant increase with Shanghai and Suzhou as the core. (2) The higher the quality of construction land potentials (CLP), the smaller the number of CLP units. High sensitive area accounted for the largest percentage (40.14%) among all types of constraint regions and this was followed by medium sensitive region (31.53%) of the whole region. (3) The comprehensive CLP in the YRD was 24,989.65 km², or 21.76% of the total YRD. The land use potential showed spatial distribution imbalance. CLP of Zhejiang was obviously larger than that of Jiangsu. CLP was insufficient in regional central city. Moreover, CLP in the YRD formed a circle layered spatial pattern that increasingly expanded centered in prefecture-level cities. Low potential area expanded from north to south. High potential area was mainly located in south YRD. Areas with zero potential in the YRD formed a northwest-southeast “Y-shaped” spatial pattern in north Hangzhou Bay. (4) CLP per capita in YRD was 0.045 ha/person and also unevenly distributed. Some 25.57% of the study units at county level nearly had no construction land and 8.24% of the units had CLP per capita below the national average level. CLP per capita in less than 25% of the county-level units was larger than the YRD average level, which were mainly located in Zhejiang. Therefore, research on the construction potential area in YRD was favorable for analysis of the development status and potential space of this region under the background of rapid urbanization and industrialization.

Land suitability assessment (LSA) is one of the key processes of land-use planning. Given its particularity of land suitability assessment for post-earthquake reconstruction, this paper takes into account geological conditions, risk of disasters, water and land resources conditions, and eco-environmental suitability and emphasizes safety factor in the assessment. Taking the April 20, 2013 Mw 6.6 Lushan earthquake as a case, this assessment establishes factors system, uses GIS spatial analysis techniques and data of geology, topography, resources, and eco-environment to evaluate the land suitability for reconstruction. The results show that: (1) the spatial characteristics of land suitability for reconstruction at grid scale and administrative scale manifest that most of the piedmont plains in the east are suitable for large-scale population aggregation, industrialization, and urbanization development; and (2) for the six hard-hit counties, Mingshan is the preferred region for large-scale post-earthquake reconstruction due to its high construction index and suitable land per capita, and some plots of land in the valleys could be selected for in-situ small-scale reconstruction in Lushan. The land suitability assessment for post-earthquake reconstruction would be significant to making sound reconstruction planning for achieving sustainable regional development in the Mw 6.6 Lushan earthquake stricken area. This study could be used as a reference for the regions with similar events.

About 80% of global wetland resources are degrading or disappearing; thus the wetland ecosystem has become one of the most seriously threatened ecosystems in the world. As an area sensitive to global changes and acting as a security barrier for the Asian ecosystem, the Tibetan Plateau has about 13.19×10⁴ km² of wetlands of special significance within China. With the increasing application of remote sensing technology to wetland research, Tibetan Plateau wetland research has entered a period of rapid development. This paper summarizes the remote sensing research literature of the Tibetan Plateau wetlands from 1992 to 2014, and is intended to provide references for future research into the wetlands of the Tibetan Plateau. We have reviewed monitoring methods, research topics, and existing problems. Our review has revealed the following characteristics: (1) Over the past 40 years, the research paradigm of the Tibetan Plateau wetlands has undergone dynamic changes in the monitoring of wetland areas, landscape patterns and the eco-environment based on remote sensing technology. Attention has also been focused on constructing models with an ecological system perspective and analyzing three patterns of change trends within the Tibetan Plateau wetlands. (2) The results of Tibetan Plateau wetland research based on remote sensing were as follows: (a) between 1970 and 2006, the Tibetan Plateau wetland area decreased overall at a rate of 0.23%/a, and the landscape diversity declined at a rate of 0.17%/a; (b) by contrast, between 1976 and 2009, the lake area of the inland river basins in the Tibetan Plateau increased at a rate of 0.83%/a; and (c) the change trend in the Tibetan Plateau wetlands was controlled by climate change. Current problems relating to remote sensing (RS)-based research in the Tibetan Plateau wetlands are computer interpretation accuracy and the processing precision of cloud removal, and the lack of a comprehensive overview of the Tibetan Plateau wetland system. Finally, based on the review, some key activities for future study have been proposed, as follows: (1) Strengthening the integration of the Tibetan Plateau wetland research with remote sensing research; (2) discussing the response and adaptation mechanisms of the Tibetan Plateau wetland ecosystem within the context of global change; (3) strengthening the integration of remote sensing (RS), geographic information system (GIS), and global positioning system (GPS), and promoting the construction of a Tibetan Plateau wetland information platform.

This study applies a hydroeconomic optimization method for water resources management in the highly water stressed Haihe River basin. A multi-objective, multi-temporal deterministic hydroeconomic optimization model has been built to quantify the economic trade-offs and reveal “minimum cost strategies” when reducing groundwater abstraction to sustainable levels. A complex basin representation, with ~140,000 decision variables is formulated where each decision variable represents a flow-path from a water source to a sink. Available water sources are runoff generated by the sub-basins upstream the nine major surface water reservoirs, the inter-basin transfers from Yellow River and South to North Water Transfer Project (SNWTP) and the natural groundwater recharge to the three main groundwater aquifers. Water demands, i.e. sinks, are aggregated for each model sub-basin in categories of the major agricultural users, domestic, industrial and ecological water demands. Each demand is associated with a curtailment cost and groundwater abstraction with a pumping cost. Groundwater overdraft is constrained in each model scenario, ranging from unlimited overdraft in the plain area groundwater aquifer to sustainable abstractions over an 8-year period. Inflow upstream Yuqiao reservoir, and the inter-basin transfers from SNWTP and Yellow River are identified as the water resources with the highest increase in average shadow prices when limiting groundwater overdraft. An increase in inflow shadow prices of 37.5% indicates that these water sources will be most valuable if sustainable groundwater abstraction should be achieved. The shadow prices of water sources reveal when and where in the Haihe River basin users are curtailed if water resources are managed in the most optimal way. Average shadow prices of 1.6 yuan/m³ for all surface water sources in the sustainable abstraction scenarios shows that overdraft can be avoided by curtailment of users with a willingness-to-pay ≤1.6 yuan/m³. The shadow prices of the existing surface water reservoirs represented in the model shows that no costs can be saved from expanding their capacities. Finally, the cost of achieving sustainable groundwater abstraction with present water resource availability is found to be minimum 8.2 billion yuan/year.

Energy is consumed at every stage of the cycle of water production, distribution, end use, and recycled water treatment. Understanding the nexus of energy and water may help to minimize energy and water consumption and reduce environmental emissions. However, the interlinkages between water and energy have not received adequate attention. To address this gap, this paper disaggregates and quantifies the energy consumption of the entire water cycle process in Beijing. The results of this study show that total energy consumption by water production, treatment and distribution, end use, and recycled water reuse amounts to 55.6 billion kWh of electricity in 2015, or about 33% of the total urban energy usage. While water supply amount increased by only 10% from 2005 to 2015, the related energy consumption increased by 215% due to water supply structural change. The Beijing municipal government plans to implement many water saving measures in the area from 2016 to 2020, however, these policies will increase energy consumption by 74 million kWh in Beijing. This study responds to the urgent need for research on the synergies between energy and water. In order to achieve the goal of low-energy water utilization in the future, water and energy should be integrated in planning and management.

Among the most devastating extreme weather events, cold surge (CS) events frequently impact northern China. It has been reported that extreme weather events will increase in the global warming context. However, the direct evidence of this hypothesis is limited. Here, we investigated the changes in frequency, number, duration, and temperature of CS events in northern China using the daily minimum temperature dataset of 331 stations from 1960 to 2016. The results indicate that the annual CS events in terms of frequency and number decreased, and the duration shortened as the starting date was later and the ending date earlier. Meanwhile, the annual CS temperature increased. In addition, spatial trends in the CS events in terms of frequency, number, and duration decreased while the CS temperature increased in most regions of northern China. We interpreted these variations as a response to global warming. However, the extreme CS events in terms of frequency, number and the earliest starting date and the latest ending date showed little change though the extreme CS temperature increased, implying climate warming had not limited extreme CS events. The adverse effect of CS events on agriculture and human health remain concerning.

In this study, we analyzed glacier changes in the Aksu River Basin during the period 1975-2016, based on Landsat MSS/TM/ETM+/OLI imagery analysis and the Chinese Glacier Inventory (CGI). The results showed that the total number, area, and volume of the studied glaciers in the Aksu River Basin decreased by 202 (7.65%), 965.7 km² (25.88%), and 74.85-78.52 km³ (23.72%-24.3%), respectively. The rate of glacier retreat in the basin was slower in the north, northwest and west, but reached the highest in the east (measuring 0.86% yr^-1). Furthermore, there were significant regional differences in the distribution and change of glaciers, the Kumalak River Basin had the largest glacier number and area, about 63.15% and 76.47% of the studied basin, and the rate of glacier retreat in the Kumalak River Basin was 0.65% yr^-1, it was higher than the Toxkan River Basin which reached 0.57% yr^-1. We found the shrinkage rate of glacier for different periods in the past 41 years, during 1975-1990 the glaciers showed the greatest retreat, while the rate of glacier area retreat slowed down significantly from 1990 to 2000. In recent 16 years since 2000, the rate of glacier retreat in the Toxkan River Basin was higher compared with 1990-2000. The RGI50-13.04920 glacier of Kumalak River Basin had been in a state of retreat since 1990. Over the past 41 years, the temperature and precipitation in the Aksu River Basin increased obviously, and the warming temperatures were clearly the main reason for glacier retreat in the region, while the increased precipitation in the mountain area may have a direct relation with the retreating rate of glaciers.

The coordinated development of urban and rural territorial systems has long been a scientific issue of concern in geography and socioeconomic development in China. Based on Territorial Function Theory, this paper establishes a theoretical framework to support the coordinated development of urban and rural territorial systems, analyzes the trend of functional evolution, discusses the impact of efficient allocation and orderly element flow on system equivalence development, and puts forward approaches and policy suggestions for equilibrium development in the future. The main conclusions are as follows: (1) The evolution of urban and rural territorial functions has experienced four stages: rural to rural, rural to urban transition, rural to urban, and urban to urban. In this process, territorial functions have been developed to be hierarchical and advanced. (2) Functional evolution enables urban and rural comparative advantages to be transformed from value difference to value equivalence. Increasing the flow intensity and reconstructing the flow space have become the necessary conditions for the coordination of development. (3) Land is the most important resource in China, and land system reform is the key to achieving equivalence development of urban and rural territorial systems, thereby determining the future equilibrium development of the two systems.