Based on long-term measurement data of weather/ecological stations over China, this paper calculated and produced annually- and seasonally-averaged Photosynthetically Active Radiation (PAR) spatial data from 1961 to 2007, using climatological calculations and spatialization techniques. The spatio-temporal variation characteristics of annually- and seasonally-averaged PAR spatial data over China in recent 50 years were analyzed with Mann-Kendall trend analysis method and GIS spatial analysis techniques. The results show that: (1) As a whole, the spatial distribution of PAR is complex and inhomogeneous across China, with lower PAR in the eastern and southern parts of China and higher PAR in the western part. Mean annual PAR over China ranges from 17.7 mol m^-2 d^-1 to 39.5 mol m^-2 d^-1. (2) Annually- and seasonally-averaged PAR of each pixel over China are averaged as a whole and the mean values decline visibly with fluctuant processes, and the changing rate of annually-averaged PAR is –0.138 mol m^-2 d^-1/10a. The changing amplitudes among four seasons are different, with maximum dropping in summer, and the descending speed of PAR is faster before the 1990s, after which the speed slows down. (3) The analysis by each pixel shows that PAR declines significantly (α=0.05) in most parts of China. Summer and winter play more important roles in the interannual variability of PAR. North China is always a decreasing zone in four seasons, while the northwest of Qinghai-Tibet Plateau turns to be an increasing zone in four seasons. (4) The spatial distributions of the interannual variability of PAR vary among different periods. The interannual variabilities of PAR in a certain region are different not only among four seasons, but also among different periods.

This paper presents a scenario-based assessment of global future food security. To do that, the socio-economic and climate change scenarios were defined for the future and were linked to an integrated modeling framework. The crop yields simulated by the GIS-based Environmental Policy Integrated Climate (EPIC) model and crop areas simulated by the crop choice decision model were combined to calculate the total food production and per capita food availability, which was used to represent the status of food availability and stability. The per capita Gross Domestic Product (GDP) simulated by IFPSIM model was used to reflect the situation of food accessibility and affordability. Based on these two indicators, the future food security status was assessed at a global scale over a period of approximately 20 years, starting from the year 2000. The results show that certain regions such as South Asia and most African countries will likely remain hotspots of food insecurity in the future as both the per capita food availability and the capacity of being able to import food will decrease between 2000 and 2020. Low food production associated with poverty is the determining factor to starvation in these regions, and more efforts are needed to combat hunger in terms of future actions. Other regions such as China, most Eastern European countries and most South American countries where there is an increase in per capita food availability or an increase in the capacity to import food between 2000 and 2020 might be able to improve their food security situation.

This paper calculated spatial accessibility of all counties (city, urban district) in China with cost weighted distance method. Region divisions of county accessibility were conducted, and relation of traffic accessibility and population aggregation was discussed in this paper. The results indicated that county accessibility in China had mainly low values and a distribution structure of circle layer and reverse-to-natural gradient. There was an obvious correlation between county accessibility and population density in China. With these analyses, inner mechanisms of population migration in different traffic conditions and region types were revealed, and can provide useful proposals to regional planning, traffic planning and smart distribution of people in China.

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.

Based on the static opaque chamber method, the respiration rates of soil microbial respiration, soil respiration, and ecosystem respiration were measured through continuous in-situ experiments during rapid growth season in semiarid Leymus chinensis steppe in the Xilin River Basin of Inner Mongolia, China. Soil temperature and moisture were the main factor affecting respiration rates. Soil temperature can explain most CO₂ efflux variations (R²=0.376–0.655) excluding data of low soil water conditions. Soil moisture can also effectively explain most of the variations of soil and ecosystem respiration (R²=0.314–0.583), but it can not explain much of the variation of microbial respiration (R²=0.063). Low soil water content (≤5%) inhibited CO₂ efflux though the soil temperature was high. Rewetting the soil after a long drought resulted in substantial increases in CO₂ flux at high temperature. Bivariable models based on soil temperature at 5 cm depth and soil moisture at 0–10 cm depth can explain about 70% of the variations of CO₂ effluxes. The contribution of soil respiration to ecosystem respiration averaged 59.4%, ranging from 47.3% to 72.4%; the contribution of root respiration to soil respiration averaged 20.5%, ranging from 11.7% to 51.7%. The contribution of soil to ecosystem respiration was a little overestimated and root to soil respiration little underestimated because of the increased soil water content that occurred as a result of plant removal.

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.

Landscape is a dynamic phenomenon that almost continuously changes. The overall change of a landscape is the result of complex and interacting natural and spontaneous processes and planned actions by man. However, numerous activities by a large number of individuals are not concerted and contribute to the autonomous evolution of the landscape in a similar way as natural processes do. There is a well-established need to detect land use and ecological change so that appropriate policies for the regional sustainable development can be developed. Landscape change detection is considered to be effectively repeated surveillance and needs especially strict protocols to identify landscape change. This paper developed a series of technical frameworks on landscape detection based on Landsat Thematic Mapper (TM) Data. Through human-machine interactive interpretation, the interpretation precision was 92.00% in 1986 and 89.73% in 2000. Based on the interpretation results of TM images and taking Yulin prefecture as a case study area, the area of main landscape types was summarized respectively in 1986 and 2000. The landscape pattern changes in Yulin could be divided into ten types.

The features of physical geography in the transitional region between Qinling Mountains and Huanghuai Plain possess transitional characters evidently in two directions: one is from the western mountain to the eastern plain and the other is from southern subtropical zone to northern temperate zone. Torrential rain, especially strong torrential rain is frequent in the transitional region, and there are many torrential rain centers. A majority of torrential rain is distributed among 100-200 m asl. The winter temperature at 100-400 m asl is higher than that in Huanghuai Plain whose altitude is lower than that of the transitional region, and the highest temperature in January appears at 350-400 m asl. The thickness of warm slope belt in the transitional region varies from 100 m to 250 m asl. The formation of torrential rain and warm slope belt is the result of joint action of atmospheric circulation and local terrain. Frequent torrential rains and warm slope belt had tremendous influences on the soil properties, plant distribution and local climate in the transitional region.

Scenario modelling and the risk assessment of natural disasters is one of the hotspots in disaster research. However, up until now, urban natural disaster risk assessments lack common procedures and programmes. This paper selects rainstorm waterlogging as a disaster to research, which is one of the most frequently occurring hazards for most cities in China. As an example, we used a small-scale integrated methodology to assess risks relating to rainstorm waterlogging hazards in the Jing’an District of Shanghai. Based on the basic concept of disaster risk, this paper applies scenario modelling to express the risk of small-scale urban rainstorm waterlogging disasters in different return periods. Through this analysis of vulnerability and exposure, we simulate different disaster scenarios and propose a comprehensive analysis method and procedure for small-scale urban storm waterlogging disaster risk assessments. A grid-based Geographical Information System (GIS) approach, including an urban terrain model, an urban rainfall model and an urban drainage model, was applied to simulate inundation area and depth. Stage-damage curves for residential buildings and contents were then generated by the loss data of waterlogging from field surveys, which were further applied to analyse vulnerability, exposure and loss assessment. Finally, the exceedance probability curve for disaster damage was constructed using the damage of each simulated event and the respective exceedance probabilities. A framework was also developed for coupling the waterlogging risk with the risk planning and management through the exceedance probability curve and annual average waterlogging loss. This is a new exploration for small-scale urban natural disaster scenario simulation and risk assessment.

Based on the statistics of glacier area variation measured in the Chinese Tianshan Mountains since 1960, the response of glacier area variation to climate change is discussed systematically. As a result, the total area of the glaciers has been reduced by 11.5% in the past 50 years, which is a weighted percentage according to the glacier area variations of 10 drainage basins separated by the Glacier Inventory of China (GIC). The annual percentage of area changes (APAC) of glaciers in the Chinese Tianshan Mountains is 0.31% after the standardization of the study period. The APAC varies widely for different drainage basins, but the glaciers are in a state of rapid retreat, generally. According to the 14 meteorological stations in the Chinese Tianshan Mountains, both the temperature and precipitation display a marked increasing tendency from 1960 to 2009 at a rate of 0.34℃·(10a)^-1 and 11 mm·(10a)^-1, respectively. The temperature in the dry seasons (from November to March) increases rapidly at a rate of 0.46℃·(10a)^-1, but the precipitation grows slowly at 2.3 mm·(10a)^-1. While the temperature in the wet seasons (from April to October) grows at a rate of 0.25 ℃·(10a)^-1, but the precipitation increases at 8.7 mm·(10a)^-1. The annual and seasonal climatic trends accelerate the retreat of glaciers.

One of the noticeable consequences of China's opening up and integration into the world economy has been an explosive demand for intellectual dialogue and knowledge exchange between China and the outside world. Despite this new demand for globalization in knowledge production, existing geographical research undertaken within and outside China has remained by and large separated because of the formidable barriers of different ideological convictions, linguistic and cultural traditions, and paradigms and practices of knowledge production. In the studies of economic geography, the gap between China and the Western world has remained so pronounced that a “bridge” or a “common ground” is badly needed (Yeung and Lin, 2003; Liu, 2009; Lin, 2009a). This situation will become self-evident when one compares the Chinese journal Jingji Dili with the English journal Economic Geography— two journals with the same title and yet totally different contents to address different audience. Against this backdrop, World Economic Geography produced by Du Debin and his associates stands out as a timely, bold, and ground-breaking contribution that fills an awkward gap existing between China and the Western world in the studies of economic geography.

Arbuscular mycorrhizal fungi (AMF) are universally mutualistic symbionts that colonize the fine roots of most vascular plants. However, the biogeographical patterns and driving factors of AMF diversity of plant roots in grasslands are not well investigated. In this study, we used high-throughput sequencing techniques and bioinformatics to evaluate the AMF richness of 333 individual plant roots in 21 natural grassland ecosystems in northern China, including the Loess Plateau (LP), the Mongolian Plateau (MP), and the Tibetan Plateau (TP). The AMF richness showed a significant parabolic trend with increasing longitude. In regional situations, the AMF richness in the grasslands of the MP (60.4 ± 1.47) was significantly higher than those of the LP (46.4 ± 1.43) and TP (44.3 ± 1.64). Plant traits (including plant families, genera, and functional groups) explained the most variation in the AMF richness across China’s grasslands, followed by energy and water; soil properties had the least effects. The results showed the biogeographical patterns of the AMF richness and the underlying dominant factors, providing synthetic data compilation and analyses in the AMF diversity in China’s grasslands.

Land use/cover change (LUCC) is a major factor affecting net primary production (NPP). According to the LUCC of the Loess Plateau from 2005 to 2015, the LUCC patterns in 2025 in three scenarios were predicted by using the Future Land Use Simulation (FLUS) model. Furthermore, taking the average NPP of various land use/cover types in 16 years as the reference scale, the changes in NPP in multi-scenario simulations are predicted and analyzed, and the impact of different land use/cover transfers on NPP is quantified. The results are as follows: (1) The land use/cover changes greatly in the baseline and fast development scenarios, and changes relatively little in the ecological protection scenarios. (2) The changes in NPP in different scenarios reflected the significant difference in the ecological protection effect. All the three scenarios promote an NPP increase, but the ecological protection scenario can promote NPP increases the most. (3) The changes in NPP caused by LUCC in the three scenarios reflected the significant difference in the various land use/cover types protection effect. Analyzing and predicting NPP changes in multi-scenario LUCC simulations in the future can provide a theoretical basis for decision makers to judge the future changes in ecological environments and ecological protection effects against different policy backgrounds.

?ngstr?m-Prescott equation (AP) is the algorithm recommended by the Food and Agriculture Organization (FAO) of the United Nations for calculating the surface solar radiation (R_s) to support the estimation of crop evapotranspiration. Thus, the a_s and b_s coefficients in the AP are vital. This study aims to obtain coefficients a_s and b_s in the AP, which are optimized for China’s comprehensive agricultural divisions. The average monthly solar radiation and relative sunshine duration data at 121 stations from 1957-2016 were collected. Using data from 1957 to 2010, we calculated the monthly a_s and b_s coefficients for each subregion by least-squares regression. Then, taking the observation values of R_s from 2011 to 2016 as the true values, we estimated and compared the relative accuracy of R_s calculated using the regression values of coefficients a_s and b_s and that calculated with the FAO recommended coefficients. The monthly coefficients, a_s and b_s, of each subregion are significantly different, both temporally and spatially, from the FAO recommended coefficients. The relative error range (0-54%) of R_s calculated via the regression values of the a_s and b_s coefficients is better than the relative error range (0-77%) of R_s calculated using the FAO suggested coefficients. The station-mean relative error was reduced by 1% to 6%. However, the regression values of the a_s and b_s coefficients performed worse in certain months and agricultural subregions during verification. Therefore, we selected the a_s and b_s coefficients with the minimum R_s estimation error as the final coefficients and constructed a coefficient recommendation table for 36 agricultural production and management subregions in China. These coefficient recommendations enrich the case study of coefficient calibration for the AP in China and can improve the accuracy of calculating R_s and crop evapotranspiration based on existing data.

This paper addresses issues on adaptive water management under the impact of climate change. Based on a set of comprehensive indicators of water system, a decision making approach of multi-objects is developed and applied to quantify water adaptive management for the demands of water sustainable use, water environmental protection and eco-water requirement under the climate change. For this study in China, two key indicators are proposed, namely (1) the water resources vulnerability (V) that was represented by integrated sensitivity (S) and resilience (C) of climate change impact on water resources, and (2) the sustainability of socio-economy and water environment, marked by DD, that is integrated scaler of socio-economic development (EG) based on the amount of GDP and the water environment and relative eco-system quality (LI). To find a reasonable solution for adaptive water management, a multi-objective decision making model of adaptive water management is further developed and the multi-objective model was transformed into an integrated single optimization model through developing an integrated measure function, called as VDD=DD/V. This approach has been applied to adaptive water resources planning and management for case study of China with new policy, called as the strict management of water resources based on three red line controls, i.e., the control of total water use by the total water resources allocation, the control of lower water use efficiency by the water demand management and the control of the total waste water load by water quality management in the Eastern China Monsoon Region that covers major eight big river basins including Yangtze River, Yellow River, Haihe River and Huaihe River. It is shown that the synthetic representation of water resource vulnerability and socio-economic sustainability by the integrated objective function (VDD) and integrated decision making model are workable and practicable. Adaptive management effect of the criterion compliance rate and water use efficiency are more appreciable through new water policy of the three red line controls, which can reduce 21.3% of the water resources vulnerability (V) and increase 18.4% of the sustainability of socio- economy and water environment (DD) for the unfavorable scenario of climate change in 2030.

Based on the statistical method and the historical evolution of meteorological stations, the temperature time series for each station in Hunan Province during 1910-2014 are tested for their homogeneity and then corrected. The missing data caused by war and other reasons at the 8 meteorological stations which had records before 1950 is filled by interpolation using adjacent observations, and complete temperature time series since the establishment of stations are constructed. After that, according to the representative analysis of each station in different time periods, the temperature series of Hunan Province during 1910-2014 are built and their changes are analyzed. The results indicate that the annual mean temperature has a significant warming trend during 1910-2014 and the seasonal mean temperature has the largest rising amplitude in winter and spring, followed by autumn, but no significant change in summer. Temperature variation over Hunan Province has several significant warm-cold alternations and more frequent than that in whole China. Annual and seasonal mean temperatures except summer and autumn have abrupt warming changes in the recent 100 years. The wavelet analysis suggests that the annual and four seasonal mean temperatures in recent 100 years have experienced two climatic shifts from cold to warm.

Lakes in the Tibetan Plateau are considered sensitive responders to global warming. Variations in physical features of lake systems such as surface area and water level are very helpful in understanding regional responses to global warming in recent decades. In this study, multi-source remote sensing data were used to retrieve the surface area and water level time series of five inland lakes in the south-central part of the Tibetan Plateau over the past decades. Changes in water level and surface area of the lakes were investigated. The results showed that the water level of three lakes (Puma Yumco, Taro Co, Zhari Namco) increased, with expanding surface area, while the water levels of the other two lakes (Paiku Co, Mapam Yumco) fell, with shrinking area. The water levels of the lakes experienced remarkable changes in 2000-2012 as compared with 1976-1999. Spatially, lakes located at the southern fringe of the Tibetan Plateau showed consistency in water level changes, which was different from lakes in the central Tibetan Plateau.

Pilot reforms gradually implemented through key nodes have become an important pattern of regional development in China since the policy of reform and opening up was introduced in 1978. On the basis of an analysis of the evolution processes and characteristics of regional development policies in post-reform China, this paper develops the concept and analytical framework of national node strategies (NNS), defined as regional development strategies centered on specific spatial nodes, by addressing their theoretical basis and research scope. The regional economic impacts of NNS were explored quantitatively through the examples of the Shenzhen Special Economic Zone, Pudong New Area and Tianjin Binhai New Area in different stages of the reform and opening up. The results indicate that the evolution of China’s regional development policies can be divided into three stages: the exploration stage led by Special Economic Zones (SEZs), the expansion stage dominated by Economic Development Zones and the optimization stage featuring State-level New Areas and National Comprehensive Reform Pilot Areas. During all the three stages, NNS have played an important demonstrative and leading role and promoted the rapid evolution of China’s regional development policies from localized to widespread implementation, and the role of the government has also changed accordingly. As an innovative application and development of the growth pole theory in transitional China, NNS have become engines of regional development as well as important conduits of institutional innovations. NNS and regional development have achieved a benign coupling and formed a gradated regional development model. Empirical research indicates that NNS are an important method used by the government to guide and regulate regional economic development, with complex and diverse economic effects that differ depending on the stage of regional development and the spatial scale of analysis.

Analysis of carbon emission mechanism based on regional perspectives is an important research method capable of achieving energy savings and emission reductions. Xinjiang, an important Chinese energy production base, is currently going through a period of strategic opportunities for rapid development. Ensuring stable socio-economic development while achieving energy savings and meeting emission reductions targets, is the key issue currently facing the region. This paper is based on the input-output theory, and conducts a structural decomposition analysis on the factors affecting energy-related carbon emissions in Xinjiang from 1997 to 2007; this analysis employs a hybrid input-output analysis framework of “energy - economy - carbon emissions”. (1) Xinjiang’s carbon emissions from energy consumption increased from 20.70 million tons in 1997 to 40.34 million tons in 2007; carbon emissions growth was mainly concentrated in the production and processing of energy resources, the mining of mineral resources, and the processing industry. (2) The analysis of the direct effects of the influencing factors on carbon emissions showed that the change in per capita GDP, the final demand structure, the population scale, and the production structure were the important factors causing an increase in carbon emissions, while the decrease in carbon emission intensity during this period was the important influencing factor in stopping the growth of carbon emissions. This showed that while the sizes of Xinjiang’s economy and population were growing, the economic structure had not been effectively optimized and the production technology had not been efficiently improved, resulting in a rapid growth of carbon emissions from energy consumption. (3) The analysis of the indirect effects of the influencing factors of carbon emission showed that the inter-provincial export, fixed capital formation, and the consumption by urban residents had significant influence on the changes in carbon emissions from energy consumption in Xinjiang. (4) The growth of investments in fixed assets of carbon intensive industry sectors, in addition to the growth of inter-provincial exports of energy resource products, makes the transfer effect of inter-provincial “embodied carbon” very significant.

Rainfall erosivity is an important climatic factor for predicting soil loss. Through the application of high-resolution pluviograph data at 5 stations in Huangshan City, Anhui Province, China, we analyzed the performance of a modified Richardson model that incorporated the seasonal variations in parameters α and β. The results showed that (1) moderate to high seasonality was presented in the distribution of erosive rainfall, and the seasonality of rainfall erosivity was even stronger; (2) seasonal variations were demonstrated in both parameters α and β of the Richardson model; and (3) incorporating and coordinating the seasonality of parameters α and β greatly improved the predictions at the monthly scale. This newly modified model is therefore highly recommended when monthly rainfall erosivity is required, such as, in planning soil and water conservation practices and calculating the cover-management factor in the Universal Soil Loss Equation (USLE) and Revised Universal Soil Loss Equation (RUSLE).

Drought is one of the most complex natural hazards affecting agriculture, water resources, natural ecosystems, and society. The negative societal consequences of drought include severe economic losses, famine, epidemics, and land degradation. However, few studies have analyzed the complexity of drought characteristics, both at multiple time scales and with variations in evapotranspiration. In this study, drought occurrences were quantified using a new drought index, the Standardized Precipitation Evapotranspiration Index (SPEI), based on observed data of monthly mean temperature and precipitation from 1961 to 2013 in Henan province, central China. Based on the SPEI values of each weather station in the study, the frequency and severity of meteorological droughts were computed, and the monthly, seasonal, and annual drought frequency and intensity over a 53-year period were analyzed. The spatial and temporal evolution, intensity, and the primary causes of drought occurrence in Henan were revealed. The results showed that the SPEI values effectively reflected the spatial and temporal pattern of drought occurrence. As the time scale decreased, the amplitude of the SPEI increased and droughts became more frequent. Since 1961, drought has occurred at the annual, seasonal, and monthly scales, and the occurrence of drought has increased. However, regional distribution has been uneven. The highest drought frequency, 35%, was observed in the Zhoukou region, while the lowest value, ~26%, was measured in central and western Henan. The most severe droughts occurred in the spring and summer, followed by autumn. Annually, wide-ranging droughts occurred in 1966-1968, 1998-2000, and 2011-2013. The drought intensity showed higher values in north and west Henan, and lower values in its east and south. The maximum drought intensity value was recorded in Anyang, and the minimum occurred in Zhumadian, at 22.18% and 16.60%, respectively. The factors with the greatest influence on drought occurrence are increasing temperatures, the Eurasian atmospheric circulation patterns, and the El Ni?o effect.

To investigate the diurnal variation of summer precipitation in the Qilian Mountains in the northeast Tibetan Plateau, the hourly precipitation amount for this region during the summers of 2008-2014 are analyzed using an hourly merged precipitation product at 0.1°×0.1° resolution. The main results are as follows. (1) The spatial distribution and temporal variation of mean hourly precipitation amount and frequency are generally similar and hourly precipitations in the eastern and middle portions are larger and more frequent than that in the western portion. The high value area of precipitation intensity is obviously different from that of precipitation amount and frequency. (2) The spatial distribution of daytime precipitation is generally similar to that of nighttime precipitation, and the daytime precipitation is heavier than the nighttime precipitation. (3) The change rate of precipitation has a maximum at 20:00 Beijing time, and a minimum at 12:00. The hourly precipitation amount significantly correlated with frequency, especially for the middle and eastern portions.

This paper reports the phenological response of forest vegetation to climate change (changes in temperature and precipitation) based on Moderate Resolution Imaging Spectroradiometer (MODIS) Enhanced Vegetation Index (EVI) time-series images from 2000 to 2015. The phenological parameters of forest vegetation in the Funiu Mountains during this period were determined from the temperature and precipitation data using the Savitzky-Golay filter method, dynamic threshold method, Mann-Kendall trend test, the Theil-Sen estimator, ANUSPLIN interpolation and correlation analyses. The results are summarized as follows: (1) The start of the growing season (SOS) of the forest vegetation mainly concentrated in day of year (DOY) 105-120, the end of the growing season (EOS) concentrated in DOY 285-315, and the growing season length (GSL) ranged between 165 and 195 days. There is an evident correlation between forest phenology and altitude. With increasing altitude, the SOS, EOS and GSL presented a significant delayed, advanced and shortening trend, respectively. (2) Both SOS and EOS of the forest vegetation displayed the delayed trend, the delayed pixels accounted for 76.57% and 83.81% of the total, respectively. The GSL of the forest vegetation was lengthened, and the lengthened pixels accounted for 61.21% of the total. The change in GSL was mainly caused by the decrease in spring temperature in the region. (3) The SOS of the forest vegetation was significantly partially correlated with the monthly average temperature in March, with most correlations being negative; that is, the delay in SOS was mainly attributed to the temperature decrease in March. The EOS was significantly partially correlated with precipitation in September, with most correlations being positive; that is, the EOS was clearly delayed with increasing precipitation in September. The GSL of the forest vegetation was influenced by both temperature and precipitation throughout the growing season. For most regions, GSL was most closely related to the monthly average temperature and precipitation in August.

The knowledge of geomorphological evolution from an estuary to a river delta is necessary to form the formulation of comprehensive land-ocean interaction management strategies. In this study, the dominant factor controlling the geomorphological variability and the threshold sediment flux (TSF) to form a river delta in Hainan Island, southern China, including accommodation space, sediment supply, and reworking forces, was investigated by the method of big data analytics. The results indicated the 25 estuaries in consideration can be divided into three geographical groups, i.e. the multi-factors-controlled northern mixed estuaries, wave-dominated western estuaries with river deltas, and typhoon-dominated eastern coastal lagoon estuaries. For alluvial plain (AP) estuaries, the order of magnitude of TSFs is the smallest (10¹ kt·yr^-1), for barrier-lagoon (BL) ones is the highest (> 10² kt·yr^-1), and for drowned valley (DV) ones is moderate (10²kt·yr^-1). The river deltas associated with DV systems should be relatively large, and those related to BLs should be small, with the AP deltas being between the above mentioned types. The present study provides a technique to evaluate the role played by TSF for the formation of river deltas in micro-tidal and wave-dominated and typhoon-influenced coastal environments.