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.

The United States, Russia and China are militarily and economically among the most powerful countries in the post-Cold War period, and the interactions between the three powers heavily influence the international system. However, different conclusions about this question are generally made by researchers through qualitative analysis, and it is necessary to objectively and quantitatively investigate their interactions. Monthly-aggregated event data from the Global Data on Events, Location and Tone (GDELT) to measure cooperative and conflictual interactions between the three powers, and the complementary cumulative distribution function (CCDF) and the vector autoregression (VAR) method are utilized to investigate their interactions in two periods: January, 1991 to September, 2001, and October, 2001 to December, 2016. The results of frequencies and strengths analysis showed that: the frequencies and strengths of USA-China interactions slightly exceeded those of USA-Russia interactions and became the dominant interactions in the second period. Although that cooperation prevailed in the three dyads in two periods, the conflictual interactions between the USA and Russia tended to be more intense in the second period, mainly related to the strategic contradiction between the USA and Russia, especially in Georgia, Ukraine and Syria. The results of CCDF indicated that similar probabilities in the cooperative behaviors between the three dyads, but the differences in the probabilities of conflictual behaviors in the USA-Russia dyad showed complicated characteristic, and those between Russia and China indicated that Russia had been consistently giving China a hard time in both periods when dealing with conflict. The USA was always an essential factor in affecting the interactions between Russia and China in both periods, but China’s behavior only played a limited role in influencing the interactions between the USA-Russia dyad. Our study provides quantitative insight into the direct cooperative and conflictual interactions between the three dyads since the end of the Cold War and helps to understand their interactions better.

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.

Lake water level is an essential indicator of environmental changes caused by natural and human factors. The water level of Poyang Lake, the largest freshwater lake in China, has exhibited a dramatic variation for the past few years, especially after the completion of the Three Gorges Dam (TGD*However, there is a lack of more accurate assessment of the effect of the TGD on the Poyang Lake water level (PLWL) at finer temporal scales (e.g., the daily scale*Here, we used three machine learning models, namely, an Artificial Neural Network (ANN), a Nonlinear Autoregressive model with eXogenous input (NARX), and a Gated Recurrent Unit (GRU), to simulate the daily lake level during 2003-2016. We found that machine learning models with historical memory (i.e., the GRU model) are more suitable for simulating the PLWL under the influence of the TGD. The GRU-based results show that the lake level is significantly affected by the TGD regulation in the different operation stages and in different periods. Although the TGD has had a slight but not very significant impact on the yearly decline of the PLWL, the blocking or releasing of water at the TGD at certain moments has caused large changes in the lake level. This machine-learning-based study sheds light on the interactions between Poyang Lake and the Yangtze River regulated by the TGD.

It is of necessity to investigate the adjustment of flood discharge capacity in the Lower Yellow River (LYR) because of its profound importance in sediment transport and flood control decision-making, and additionally its magnitude is influenced by the channel and upstream boundary conditions, which have significantly varied with the ongoing implementation of soil and water conservation measures in the Loess Plateau and the operation of the Xiaolangdi Reservoir. The braided reach between two hydrometric stations of Huayuankou and Gaocun in the LYR was selected as the study area. Different parameters in the study reach during the period 1986-2015 were calculated, covering bankfull discharge (the indicator of flood discharge capacity), the pre-flood geomorphic coefficient (the indicator of channel boundary condition), and the previous five-year average fluvial erosion intensity during flood seasons (the indicator of incoming flow and sediment regime*Functional linkages at scales of section and reach were then developed respectively to quantitatively demonstrate the integrated effects of channel and upstream boundary conditions on the flood discharge capacity. Results show that: (1) the reach-scale bankfull discharge in the pre-dam stage (1986-1999) decreased rapidly by 50%, accompanied with severe channel aggradation and main-channel shrinkage. It recovered gradually as the geometry of main channel became narrower and deeper in the post-dam stage, with the geomorphic coefficient continuously reducing to less than 15 m^-1/2*2) The response of bankfull discharge to the channel and upstream boundary conditions varied at scales of section and reach, and consequently the determination coefficients differed for the comprehensive equations, with a smallest value at the Jiahetan station and a highest value (0.91) at reach scale. Generally, the verified results calculated using the comprehensive equations agreed well with the corresponding measured values in 2014-2015*3) The effect of channel boundary condition was more prominent than that of upstream boundary condition on the adjustment of bankfull discharge at the Jiahetan station and the braided reach, which was proved by a larger improvement in determination coefficients for the comprehensive equations and a better performance of geomorphic coefficient on the increase of bankfull discharge.

Tidal creeks are the main channels of land-sea ecosystem interactions, and their high dynamics are an important factor affecting the hydrological connectivity of tidal flats. Taking the Yellow River Delta as the research area, we selected remote sensing images obtained during five periods from 1998 to 2018 as the data sources. Based on the spatial analysis function in GIS, the typical morphological characteristics of tidal creeks, such as the level, length, density, curvature, bifurcation ratio, and overmarsh path length (OPL), were extracted to characterize the degree of development of the tidal creeks in the Yellow River Delta wetlands. The spatio-temporal evolution of the tidal creeks was studied, and the development process and the characteristics of the tidal creeks during the different stages of development were investigated. The results revealed that (1) The number, density, and bifurcation ratio of tidal creeks exhibit an increasing trend, but the growth of the trend is slowing. The number of tidal creeks increased by 44.9% from the initial stage of the Yellow River diversion to the late stage of the wetland restoration, but it only increased by 26.2% from the late stage of the wetland restoration to the slow expansion of the Spartina alterniflora*2) The curvature of the tidal creeks on the landward side is greater than that on the seaward side*3) The development degree of tidal creek has spatial heterogenetiy, which is Area III > Area II > Area I*4) The drainage efficiency is significantly correlated with the tidal creak density and bifurcation ratio. Based on the analysis of the various morphological parameters and the drainage efficiency, it was found that after the rapid change in the tidal creek system in the early stage, the tidal creeks entered a state of slow change, and the development state of the tidal creeks tends to be in dynamic balance. The results of this study are expected to provide scientific support for the sustainable development and utilization of coastal tidal flats.

Heavy metal pollution is hazardous for the environment and human health. However, there are few studies of heavy metal pollution caused by historic metallurgical activity. The Laoniupo site in the Bahe River valley, Guanzhong Basin, China, was an important settlement of the Shang Culture (1600-1046 BCE*We studied two stratigraphic profiles at the Laoniupo site, which were used for measurements of magnetic susceptibility, heavy metal concentrations, and AMS ¹⁴C ages to provide evidence of copper smelting activity at the site during the Shang Dynasty. The Nemerow Pollution Index and Geoaccumulation Index were calculated to assess the heavy metals record (Cu, Zn, Ni, Pb, Cr, and As) in the topsoil on the loess tableland. According to the Single Pollution Index, the topsoil was slightly polluted by As and unpolluted by Cu, Zn, Ni, Pb and Cr; according to the Nemerow Composite Pollution Index the topsoil was mildly polluted; and according to the Geoaccumulation Index, the topsoil was moderately polluted by As, slightly polluted by Cu, and unpolluted by Zn, Ni, Pb and Cr. The main cause of the heavy metal pollution in the topsoil is the presence of copper slag in the cultural layers that was disturbed by modern farming activity.

Background vales (mg/kg)

Since the Bonn 2011 conference, the “water-energy-food” (WEF) nexus has aroused global concern to promote sustainable development. The WEF nexus is a complex, dynamic, and open system containing interrelated and interdependent elements. However, the nexus studies have mainly focused on natural elements based on massive earth observation data. Human elements (e.g., society, economy, politics, culture) are described insufficiently, because traditional earth observation technologies cannot effectively perceive socioeconomic characteristics, especially human feelings, emotions, and experiences. Thus, it is difficult to simulate the complex WEF nexus. With the development of earth observation sensor technologies and human activity perception methods, geographical big data covering both human activities and natural elements offers a new opportunity for in-depth WEF nexus analysis. This study proposes a five-step framework by leveraging geographical big data mining to dig for the hidden value in the data of various natural and human elements. This framework can enable a thorough and comprehensive analysis of the WEF nexus. Some application examples of the framework, major challenges, and possible solutions are discussed. Geographical big data mining is a promising approach to enhance the analysis of the WEF nexus, strengthen the coordinated management of resources and sectors, and facilitate the progress toward sustainable development.

Wetlands are important natural resources for humans and play an irreplaceable ecological function in the terrestrial ecosystem. To curb the continued loss of wetlands globally, international organizations and many countries have taken a series of major conservation and restoration measures. This work reviews these wetland conservation and restoration measures, interprets China’s wetland conservation and restoration management policies, and proposes that future research on wetland resources in China should be conducted from the aspects of international frontiers and national strategic plans, socioeconomics, and smart services. The results show that the 27 International Wetlands Days from 1997 to 2023 provided new goals and tasks for the protection and management of wetlands. The important topics and outcomes of the 14 Conferences of the Contracting Parties to the Convention on Wetlands from 1980 to 2022 provided new directions and new challenges for wetland development. In the future, we should enhance wetland ecological functions, promote sustainable wetland development, and overcome the technical bottleneck of fragile wetland ecosystem restoration. From 1992 to 2022, China embarked on a new phase of wetland protection and restoration. The overall experience of wetland protection and restoration in China has been formed through national strategic deployment, legal policy establishment, and project planning and implementation. The needs to provide for and plan the long-term protection of wetlands at the national level, to innovate restoration and management techniques and application systems, and to effectively address the complex issues of wetland protection and restoration through collaborative division of labor among multiple departments were emphasized. Research on the future trends of wetlands should be directed towards the exploration and practice of the United Nations Sustainable Development Goals and several international conventions in support of sustainable wetland development. Wetland protection, restoration, and management services should be promoted for national strategic needs and local, high-quality social and economic development. In addition, research on cross-integration and academic innovation should be enhanced for disciplinary development, global supervision, comprehensive assessment, and smart decision making.

In this study, the interplay between ecosystem services and human well-being in Seni district, which is a pastoral region of Nagqu city on the Qinghai-Tibet Plateau, is investigated. Employing the improved InVEST model, CASA model, coupling coordination model, and hierarchical clustering method, we analyze the spatiotemporal patterns of ecosystem services, the levels of resident well-being levels, and the interrelationships between these factors over the period from 2000 to 2018. Our findings reveal significant changes in six ecosystem services, with water production decreasing by 7.1% and carbon sequestration and soil conservation services increasing by approximately 6.3% and 14.6%, respectively. Both the habitat quality and landscape recreation services remained stable. Spatially, the towns in the eastern and southern areas exhibited higher water production and soil conservation services, while those in the central area exhibited greater carbon sequestration services. The coupling and coordination relationship between ecosystem services and human well-being improved significantly over the study period, evolving from low-level coupling to coordinated coupling. Hierarchical clustering was used to classify the 12 town-level units into five categories. Low subjective well-being townships had lower livestock breeding services, while high subjective well-being townships had higher supply, regulation, and support ecosystem services. Good transportation conditions were associated with higher subjective well-being in townships with low supply services. We recommend addressing the identified transportation disparities and enhancing key regulatory and livestock breeding services to promote regional sustainability and improve the quality of life for Seni district residents, thus catering to the diverse needs of both herdsmen and citizens.

Traditional music is an important component of cultural heritage. However, studies have scarcely explored the tourism development potential and the obstacle factors of traditional music. This study takes Xiangxi as the research site, constructs an evaluation index system, and utilizes survey and geographical methods. The major research results are as follows: First, the average potential of resource endowment, tourism industry development, and socio-economic conditions are 0.28, 0.36, and 0.24, respectively. The potential of resource endowment is higher in the west and lower in the east, that of tourism industry development is higher in the north and south and lower in the center, and that of socio-economic conditions is higher in the south and lower in the north. Second, the comprehensive potential is 0.29, which is higher in the northwest and southwest regions. Coordination in most administrative units is at a medium level, and most regions have obvious advantages in resource endowment. Third, the primary obstacle factor is socio-economic conditions (39.21%), followed by resource endowment (30.73%) and tourism industry development (30.06%). The administrative units can be classified into four groups: socio-economic condition obstacle, resource endowment and tourism industry development obstacles, resource endowment and socio-economic condition obstacles, and tourism industry development and socio-economic condition obstacles. The highest priority goals for Xiangxi involve economic development and the integration of modern technologies to stimulate passenger flow. For regions with limited traditional music items (eastern area of Xiangxi), tourism development should be restrained and other resources with stronger inherent advantages should be exploited. This study explored the quantification of traditional music tourism potential, representing a novel breakthrough in this field of research. The indicator system and research methods used in this study can provide guidance and methodological references for cultural heritage research. The suggestions proposed in this article contribute to the rational development and effective protection of cultural heritage resources and the healthy development of the tourism industry.

The transboundary influence of environmental change is a critical issue in the Lancang-Mekong region. As the largest river-connected lake in the lower Mekong, the ecological change and influence of Tonle Sap Lake have received widespread attention and discussion, especially after 2008, when the hydrological regime of the Lancang-Mekong River mainstream underwent distinct changes. However, the linkage and coupling mechanism between the lake riparian environment and mainstream water level change are still unclear. In this study, the interannual spatiotemporal changes in land cover in the Tonle Sap Lake riparian zone (TSLRZ) and their relationship with mainstream water levels were analysed. The results showed that the expansion of farmland was the most notable change in 1988-2020. After 2008, the land cover changes intensified, manifested as accelerated farmland expansion, intensified woodland fragmentation and significant water body shrinkage. Furthermore, the responses of the water body, degraded land, wasteland and grassland areas to the mainstream water levels weakened after 2008. Evidently, the land cover changes in the TSLRZ in the last 30 years were less related to the mainstream water level change than to local reclamation and logging. These results can offer a new scientific basis for the transboundary influence analysis of hydrological change.

Significant changes to the world’s climate over the past few decades have had an impact on the development of plants. Vegetation in high latitude regions, where the ecosystems are fragile, is susceptible to climate change. It is possible to better understand vegetation’s phenological response to climate change by examining these areas. Traditional studies have mainly investigated how a single meteorological factor affects changes in vegetation phenology through linear correlation analysis, which is insufficient for quantitatively revealing the effects of various climate factor interactions on changes in vegetation phenology. We used the asymmetric Gaussian method to fit the normalized difference vegetation index (NDVI) curve and then used the dynamic threshold method to extract the phenological parameters, including the start of the season (SOS), end of the season (EOS), and length of the season (LOS), of the vegetation in this study area in the Tundra-Tagar transitional zone in eastern and western Siberia from 2000 to 2017. The monthly temperature and precipitation data used in this study were obtained from the climate research unit (CRU) meteorological dataset. The degrees to which the changes in temperature and precipitation in the various months and their interactions affected the changes in the three phenological parameters were determined using the GeoDetector, and the results were explicable. The findings demonstrate that the EOS was more susceptible to climate change than the SOS. The vegetation phenology shift was best explained by the climate in March, April, and September, and the combined effect of the temperature and precipitation had a greater impact on the change in the vegetation phenology compared with the effects of the individual climate conditions. The results quantitatively show the degree of interaction between the variations in temperature and precipitation and their effects on the changes in the different phenological parameters in the various months. Understanding how various climatic variations effect phenology changes in plants at different times may be more intuitive. This research provides as a foundation for research on how global climate change affects ecosystems and the global carbon cycle.

The variation of land surface temperature (LST) has a vital impact on the energy balance of the land surface process and the ecosystem stability. Based on MDO11C3, we mainly used regression analysis, GIS spatial analysis, correlation analysis, and center-of -gravity model, to analyze the LST variation and its spatiotemporal differentiation in China from 2001 to 2020. Furthermore, we employed the Geodetector to identify the dominant factors contributing to LST variation in 38 eco-geographic zones of China and investigate the underlying causes of its pattern. The results indicate the following: (1) From 2001 to 2020, the LST climate average in China is 9.6℃, with a general pattern of higher temperatures in the southeast and northwest regions, lower temperatures in the northeast and Qinghai-Tibet Plateau, and higher temperatures in plains compared to lower temperatures in mountainous areas. Generally, LST has a significant negative correlation with elevation, with a correlation coefficient of -0.66. China’s First Ladder has the most pronounced negative correlation, with a correlation coefficient of -0.76 and the lapse rate of LST is 0.57℃/100 m. (2) The change rate of LST in China during the study is 0.21℃/10 a, and the warming area accounts for 78%, demonstrating the overall spatial pattern a “multi-core warming and axial cooling”. (3) LST’s variation exhibits prominent seasonal characteristics in the whole country. The spatial distribution of average value in winter and summer differs significantly from other seasons and shows more noticeable fluctuations. The centroid trajectory of the seasonal warming/cooling area is close to a loop shape and displays corresponding seasonal reverse movement. Cooling areas exhibit more substantial centroid movement, indicating greater regional variation and seasonal variability. (4) China’s LST variation is driven by both natural influences and human activities, of which natural factors contribute more, with sunshine duration and altitude being key factors. The boundary trend between the two dominant type areas is highly consistent with the “Heihe-Tengchong Line”. The eastern region is mostly dominated by human activity in conjunction with terrain factors, while the western region is predominantly influenced by natural factors, which enhance/weaken the change range of LST through mutual coupling with climate, terrain, vegetation, and other factors. This study offers valuable scientific references for addressing climate change, analyzing surface environmental patterns, and protecting the ecological environment.

Lake surface water-heat exchange and its climatic attribution critically influence alpine lakes’ evaporation mechanism and water storage balance with climate change. Here, this paper first explored the hourly, daily, and monthly water-heat flux variations of the lake surface and their correlations with meteorological factors based on the eddy covariance turbulent flux observation over the Yamzhog Yumco, an alpine lake in south Tibet in the non-freezing period (April-December) in 2016 and 2017. We found that the average latent heat flux was much higher than the sensible heat flux on the lake surface from April to December. Meanwhile, the water-heat flux exhibited remarkable seasonal variation, with a prominent role of higher air temperature and humidity in summer jointly controlling the lake-air energy exchange. Moreover, the main controlling meteorological factors for the water-heat flux variation of the lake surface differed with diversified timescales. First, the lake-air temperature difference was the most significant meteorological factor related to sensible heat flux on the half-hourly, daily, and monthly timescales. Second, the latent heat flux was strongly positively correlated with wind speed and the synergies of wind speed and water vapor pressure deficit on the daily and half-hourly timescales. Third, the lake surface heat flux was significantly negatively correlated with net radiation flux on the daily and monthly scales. The negative correlation can be attributed to the seasonal variation of the water surface net radiation, and the phase difference in heat flux intensity caused by the lake-air temperature difference and heat capacity contrast. Our findings will hopefully improve the understanding of energy exchange and evaporation mechanisms for alpine lakes in a warming climate.

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.