【Applied Geography】How rural community after a disaster? A case study of the easter Qinghai-Tibetan Plateau,China
论文信息：
Huizhen Su, Xueyan Zhao*, Lucang Wang, Yuheng Li. How rural community after a disaster? A case study of the easter Qinghai-Tibetan Plateau,China. Applied Geography, 2024, 165: 103238.
论文摘要：
Frequent occurrence of natural disasters has become one of the most serious challenges to human society. As rural communities are the forefront of disasters, enhancing the resilience of rural community is crucial to mitigate the impact of natural disasters and seek rapid recovery. This paper provides an analytical framework for changing trajectories of the resilience of rural communities after disasters. Taking the disaster area affected by the catastrophic debris flow in China as an example, we analyze the changing trajectories of rural community resilience after disaster in three villages with different damage levels from 2010 to 2020 based on the data from key person interviews, the disaster situation and development reports, village work records and farmers’ questionnaires. We found that the changes of community resilience after disaster show obvious stages due to the difference in the intensity of effects of government intervention and community self-organization ability during disaster relief reconstruction period and self-recovery period. The resilience of communities with different disaster losses showed an increasing trend. However, during the disaster relief and reconstruction period, the resilience of the severely affected community was improved faster, followed by the most severely affected community, while the resilience of generally affected community was improved more slowly. During the self-recovery period, the resilience of the affected general community was improved faster than that of the other two communities. The evolution process of community resilience reflects the increasing role of self-organizational capacity in post-disaster community development, aligning with the overall global trend in rural community governance. In addition, there is a significant sequence in the improvement speed of different dimensions of community resilience at different stages after disasters. During the disaster relief and reconstruction period, the resilience of community management was improved faster and the resilience of environment was slower. During the self-recovery period, the economic resilience of community was improved faster and the social resilience was improved slower. Finally, some suggestions were put forward to strengthen natural disasters prevention and community resilience in disaster-prone areas.
【Journal of Cleaner Production】Spatial identification and priority conservation areas determination of wilderness in China
论文信息：
Li Ma, Jinghu Pan*. Spatial identification and priority conservation areas determination of wilderness in China. Journal of Cleaner Productio, 2024, 451: 142069.
论文摘要：
In the context of an increasingly severe ecological crisis and accelerating ecological civilization construction, the specific regional differences as well as the natural environment of China restrict the uniform population distribution and the social economy's spatial layout, forming a large and widely distributed wilderness. The post-2020 Global Biodiversity Framework (GBF) takes the protection of wilderness areas as one of the key conservation goals and brings new opportunities for wilderness protection. Objective and accurate identification of the spatial range of wilderness and the determination of the focus of wilderness protection are significant for carrying out resource and environmental carrying capacity evaluations, biodiversity conservation, and national park system construction. At present, fewer studies pay attention to wilderness area identification and protection in China. In this study, we used the MaxEnt and Marxan models to establish a framework to identify the spatial distribution and conservation priorities of China's wilderness as well as guide wilderness conservation. The wilderness areas in China show a large-scale, concentrated distribution in space and a small, scattered distribution. From 2000 to 2020, the wilderness area decreased from 3.6323 million km2 in 2000 to 2.9142 million km2 in 2020, and the wilderness area reduction rate from 2000 to 2010 was greater than that in 2010–2020. From 2000 to 2020, the center of gravity of the wilderness area shifted 893.5 km to the southwest. Wilderness center of gravity relocated from Pingluo County, Ningxia Hui Autonomous Region to Delingha City, Qinghai Province. Considering conservation objectives and conservation costs, we determined that the wilderness area in urgent need of protection is 55,100 km2, accounting for 1.8% of the total wilderness area. It is mainly distributed in Xinjiang Uygur Autonomous Region (13,000 km2), Yunnan Province (12,000 km2), and Sichuan Province (5300 km2). This methodological framework can provide an important reference for governments in dealing with global climate change, maintaining biodiversity and ecosystem diversity, and promoting sustainable human development.
【Journal of Hydrology】An integrated approach to reconstructing snow cover under clouds and cloud shadows on Sentinel-2 Time-Series images in a mountainous area
论文信息：
Yanli Zhang* (张彦丽), Yuyu Song, Changqing Ye, Jingfeng Liu. An integrated approach to reconstructing snow cover under clouds and cloud shadows on Sentinel-2 Time-Series images in a mountainous area. Journal of Hydrology, 2023, 619: 129264.
论文摘要：
Snow is an important type of surface cover and an important freshwater resource in the arid regions of northwest China, and optical satellites are an important means for monitoring variation in snow cover. However, the radiation values measured by satellite sensors are affected by cloud cover and cloud shadows; thus, the reconstruction of snow cover under clouds and cloud shadows becomes a bottleneck problem especially in mountains areas. Based on the digital elevation model (DEM), in this paper, an integrated method of snow cover reconstruction on Sentinel-2 images is created by combining the improved SNOWL (snow line) algorithm considering unstable snow cover areas, Fmask cloud detection algorithms, and the Sen2Cor clear sky snow cover detection tool with a geospatial processing platform, GEE (Google Earth Engine). Considering the Babao River Basin as the study area, 474 Sentinel-2 scenes (10 m) were selected to obtain the snow cover spatiotemporal variations of 158 days from November 2016 to March 2021. Compared with the high-resolution GF-2 satellite images, the integrated method can extract snow under clouds and cloud shadows well, and the improved SNOWL algorithm improves the overall accuracy from 66.05 % to 84.26 %. The experimental results show that approximately half of the Babao River Basin is unstable snow cover, and areas above 3977 m are covered with snow for at least half a year
【Applied Geography】Landscape-based ecological resilience and impact evaluation in arid inland river basin: A case study of Shiyang River Basin
Yimin Wang, Jinghu Pan*. Landscape-based ecological resilience and impact evaluation in arid inland river basin: A case study of Shiyang River Basin. Applied Geography, 2024, 167: 103299.
论文摘要：
Due to extreme weather and human disturbances, the ecological conditions in the arid inland river basins of Northwest China are becoming more precarious. Furthermore, tackling a variety of ecological concerns and improving ecosystem stability depends heavily on ecological resilience (ER). We measure the spatial pattern of the overall ER of the Shiyang River Basin (SRB) by incorporating the landscape pattern into the multi-indicator evaluation system based on previous ER evaluations and combining the weights of the indicators calculated by the particle swarm optimization (PSO) algorithm. After that, we use the eXtreme Gradient Boosting (XGBoost) algorithm to analyze the impacts of the various ER factors. Results showed that among the 17 ecological sources identified in the SRB, the Qilian Mountain region hosted the largest ecological source, and all of the sources had excellent ecological values. The area with the highest ER value in the SRB is located in the Qilian Mountain region. In the overall feature importance results of the basin estimated by XGBoost, dPC obtained the highest score of 0.74; additional study of the various regions revealed the spatial heterogeneity of the ER impact factors in various regions. This study advances the methodological framework for evaluating ecological resilience from the standpoint of landscape patterns, which can enhance the arid inland river area's ecological environment quality and offer strong backing for improved management of the basin's ecological protection efforts.
【Sustainable Cities and Society】Impacts of coordinated development policies on urban heat islands in the Beijing-Tianjin-Hebei urban agglomeration, China
论文信息：
Wen Fang, Jianjun Cao*, Asim Biswas, Qi Feng, Yuyao Wang. Impacts of coordinated development policies on urban heat islands in the Beijing-Tianjin-Hebei urban agglomeration, China. Sustainable Cities and Society, 2024, 112: 105614.
论文摘要：
The accelerated process of urbanization has led to a crisis in the urban thermal environment, giving rise to the urban heat island (UHI) phenomenon. During summer, the UHI is compounded by heat waves, exacerbating heat stress. We utilized MODIS and Landsat images to extract surface temperature data during summer in the Beijing-Tianjin-Hebei urban agglomeration (BTH) from 2000 to 2021 in China. By employing spatial autocorrelation with Getis-Ord Gi*, we classified the intensities of heat islands, enabling us to explore the spatial and temporal variations in the UHI and its influencing factors. Our findings revealed the following: (1) Between 2000 and 2021, the overall UHI experienced a 7.26 % increase, and a pronounced polarization was observed, characterized by a prevalence of more intense heat and cold islands. (2) The UHI was more influenced by the interplay of anthropogenic factors, with notable contributions from impervious surfaces (16.03 %), population (15.06 %), and energy consumption (14.88 %). (3) Co-development policies enhanced the UHI, of which the components of Residential (0.432), Public facilities (0.421) and Enterprise (0.391) were major promoters. In conclusion, this study significantly advances our understanding of UHI in urban agglomerations and holds great significance for sustainable development planning.
【Ecological Indicators】Response of ecological environment quality to land use transition based on dryland oasis ecological index (DOEI) in dryland: A case study of oasis concentration area in Middle Heihe River, China
论文信息：
Wanyuan Chen, Ruifeng Zhao*, Haitian Lu. Response of ecological environment quality to land use transition based on dryland oasis ecological index (DOEI) in dryland: A case study of oasis concentration area in Middle Heihe River, China. Ecological Indicators, 2024, 165: 112214.
论文摘要：
Oasis ecosystems in dryland regions take on crucial significance in human survival and development since the quality of these regions that are characterized by ecological environments directly affects the well-being and socio-economic progress of their residents. Accordingly, it is of utmost importance to evaluate changes in ecological environment quality (EEQ) and gain insights into how land use transformation affects the local ecological condition, thus guiding the sustainable development of the dryland oasis. In this study, we evaluated the EEQ of the Middle Heihe River (MHR) from 1985 to 2020 by constructing the dryland oasis ecological index (DOEI) through the Google Earth Engine (GEE) platform. Moreover, we investigated how land use transformation influenced the EEQ of the MHR. Results suggested that (1) the DOEI can effectively capture the comprehensive dynamics of long-term EEQ changes in MHR, providing a more accurate representation of land type characteristics. (2) The EEQ in MHR generally exhibited a trend of initial improvement, followed by deterioration. The desert-oasis transition zone acts as the most significant area of EEQ changes in the MHR. The mutual transformation among cropland, grassland and desert is the primary factor for EEQ in the MHR. (3) The expansion of cropland in the MHR pronouncedly affected the EEQ. However, this continuous expansion may impose greater stress on water resources while potentially threatening ecological degradation in the lower reaches of the river basin. The DOEI built through the GEE platform is capable of indicating the spatiotemporal status of the EEQ in the dryland oasis, which holds significant implications for studying the interaction between human activities and EEQ in the dryland oasis.
【Global and Planetary Change】Interannual variations in stable isotopes of atmospheric water in arid Central Asia due to changes in atmospheric circulation
论文信息：
Shengjie Wang, Gahong Yang, John Bershaw, Xiaokang Liu, Kei Yoshimura, Yanqiong Xiao, Mingjun Zhang*. Interannual variations in stable isotopes of atmospheric water in arid Central Asia due to changes in atmospheric circulation. Global and Planetary Change, 2024, 234: 104367.
论文摘要：
The oxygen isotope compositions in atmospheric water including water vapor and precipitation have been widely used to trace moisture sources and to reconstruct past climates. However, the environmental controls of stable isotopes in atmospheric water depend on the time scales. Because of limited observations in arid Central Asia, factors controlling interannual variations in atmospheric water isotopes are still not clear. Using an isotope-enabled general climate model, we do not find at the annual scale the significant relationship between temperature and δ18O values during 1979–2020 that is usually observed at the monthly scale. Under a warming background, there is no significant enriching trend in water isotopes. We found a strong positive correlation between westerly (and southerly) water vapor flux and δ18O values on an interannual scale for the area between 35°N–50°N and 50°E–80°E in the upstream direction. High and low δ18O years are characterized by different atmospheric circulations of mid-latitude Westerlies, and do not always correspond to the warm and cold years respectively. When the prevailing Westerlies are enhanced, the Westerlies circulation may carry more water vapor from the lower latitudes, leading to higher δ18O values in Central Asia. The changes in Westerlies circulation are supported by the clustered backward trajectories during enriched and depleted years. The limited precipitation isotope observations also show similar findings as the simulations on an interannual scale. The interannual variations of stable isotopes in atmospheric water in arid Central Asia reflect the changes in the mid-latitude Westerlies circulation. This should be taken into account when interpreting oxygen isotope proxies of paleoclimate records.
【Journal of Hydrology】Altitude effect of precipitation isotopes in an arid mountain-basin system: Observation and modelling around the world’s second-largest shifting desert
论文信息：
Shengjie Wang, Liwei Wang, Gahong Yang, Yanqiong Xiao, Athanassios A. Argiriou, Yudong Shi, Shijun Lei, Mingjun Zhang*. Altitude effect of precipitation isotopes in an arid mountain-basin system: Observation and modelling around the world’s second-largest shifting desert. Journal of Hydrology, 2024, 636: 131351.
论文摘要：
The stable water isotopes of precipitation provide important information about the hydrological circulation. In the arid mountain-basin system in central Asia, the altitude effect of precipitation isotopes has been a controversial topic in recent years, but the sample availability in extreme environments constrains the accurate understanding of the relationship between altitude and stable isotopes in precipitation. Based on the observation of precipitation isotopes around the Tarim Basin covered by the world’s second-largest shifting desert, we examined the relationship between altitude and isotope composition. There is an altitude effect of precipitation isotopes between the basin and the surrounding mountains, with the modelled gradient for annual mean δ18O being approximately 1.96 ‰ per 1000 m, which is weaker than the observed gradient focusing on the oases (2.75 ‰ per 1000 m). The largest modelled difference in δ18O between 1000–2000 m and 2000–3000 m above sea level occurs in August and September. The periods with a larger gradient of altitude effect usually have higher temperature and more precipitation. Across the westerlies-dominated central Asia, the below-cloud evaporation enhances the altitude gradient of precipitation isotopes for most areas. The findings are useful to understand the local and remote drivers of precipitation isotopes and the paleoaltimetry of stable isotopes in climate proxies.
【Global and Planetary Change】Drought determines the growth stability of different dominant conifer species in Central Asia
论文信息：
Dashi Du, Liang Jiao*, Xuan Wu, Ruhong Xue, Mengyuan Wei, Peng Zhang, Qian Li, Xuge Wang. Drought determines the growth stability of different dominant conifer species in Central Asia. Global and Planetary Change, 2024, 234: 104370
论文摘要：
Accelerated drought-induced tree decline and mortality in Central Asia has threatened forest health and ecological services functions under global climate change. There is also uncertainty about the response mechanisms and ecological adaptation strategies of different tree species. Therefore, we compared differences in the growth-climate sensitivity and ecological adaptations of different tree species using tree-ring width data records from 84 sites of 5 tree species in central Asia. Four main conclusions were drawn: 1) Tree growth patterns represented by basal area increment (BAI) indicated that the radial growth trends of Pieca crassifolia (PC, 0.531 cm2yr−1/10a) was significantly increasing, while those of Sabina przewalskii (SP, 0.267 cm2yr−1/10a) and Pinus sylvestris (PSY, −0.562 cm2yr−1/10a) showed the opposite growth trend and growth variability, and those of Larix sibirica (LS) and Picea schrenkiana (PSC) were insignificant. 2) Correlation analysis of climatic factors limiting radial growth indicated that drought caused by reduced precipitation was the main cause of tree growth limitation, with the strongest limitation on PC, SP, and PSY. All tree species were insensitive to temperature, and PSC, SP, and PSY showed a stable positive response to scPDSI in spring and summer of the current year. 3) Quantile regressions demonstrated that low values of drought did not correspond exactly to low values of tree growth (BAI) and were even significantly correlated with high values of growth of PC, SP and PSY. 4) PSY and SP at higher and lower elevations showed the greatest variation with the lowest resistance, the highest recovery and resilience, and maintained consistent adaptation strategies under the most severe summer drought stress. This work contributes to existing knowledge regarding tree growth-climate response patterns in arid zones under drier climates in the future.
【Cities】Spatiotemporal characteristics of residents’ intercity travel in China under the impact of COVID-19 pandemic
论文信息：
Shimei Wei, Jinghu Pan*. Spatiotemporal characteristics of residents’ intercity travel in China under the impact of COVID-19 pandemic. Cities, 2024, 152: 105206.
论文摘要：
Investigating the spatiotemporal characteristics of residents' intercity travel affected by the coronavirus disease (COVID-19) pandemic is of great significance to understanding and extending the impact of major public health affairs on intercity travelers, urban management policies, and intercity cooperative interactions. Taking 366 cities in China as an example, this study proposed a novel research framework for analyzing the spatiotemporal characteristics of intercity population flows. Using AutoNavi population migration big data sets from web crawling, the spatiotemporal structure patterns of intercity travel in China from January 1st to June 30th, 2020 were extracted by using the singular value decomposition (SVD) method. Then the spatial organization patterns of intercity travel networks in China and its five major urban agglomerations were identified by the weighted stochastic block model (WSBM). The results showed that the total volume of intercity travel in China and its five major urban agglomerations experienced a process of rapid decline followed by a slow recovery, presenting a “V-shaped” distribution since the outbreak of the COVID-19 pandemic. Three distinctive intercity travel patterns, namely the stable, holiday, and weekday-weekend intercity trip patterns, were extracted from the spatiotemporal OD matrix of intercity travel. Strong intercity travels were mainly distributed in eastern and central China, forming an intercity travel pattern in which core cities pushed and pulled each other within the national urban agglomerations. However, intercity migration flows were dominated by weak-intensity flows. Intercity trips during the holidays had a phenomenon of “escaping from the metropolis”. Meanwhile, it had significant spatial proximity and directionality. The daily intercity trips were characterized by a remarkable periodicity with seven days as a repeat. A more interesting finding is that when weekends overlap with holidays, intercity travel on the 1–2 days before the vacations has presented an effect of “suppression travel”. Furthermore, at the national scale, the stable intercity travel network has formed a polycentric core-periphery structure of “Three Cores-Six Semi-peripheries-Five Peripheries”. At the urban agglomeration scale, they formed respectively distinguished monocentric, bicentric, and polycentric core-periphery structures.
【Journal of Hydrology】Quantifying the below-cloud evaporation of raindrops using near-surface water vapour isotopes: applications in humid and arid climates in East Asia
论文信息：
Shengjie Wang, Yudong Shi, Meng Xing, Huawu Wu, Hongxi Pang, Shijun Lei, Liwei Wang, Mingjun Zhang*. Quantifying the below-cloud evaporation of raindrops using near-surface water vapour isotopes: applications in humid and arid climates in East Asia. Journal of Hydrology, 2024, 638: 131561.
论文摘要：
In global hydrological circulation, evaporation widely occurs from the land, the oceans, and other water surfaces. Compared to the evaporation from open water, the below-cloud evaporation of falling raindrops is more difficult to quantify. As an alternative to the traditional microphysical model, the difference in stable water isotopes between water vapour and precipitation provides a new perspective to estimate the raindrop mass loss. According to the recent observations of stable isotopes in near-surface water vapour and precipitation in five sampling stations from humid to arid climates in East Asia, we quantified the below-cloud evaporation of raindrops using both a microphysical model and an isotope inversion model. The results indicate that the isotope inversion model, relative to the microphysical model, usually underestimates the impact of below-cloud evaporation on precipitation, especially in arid inland. The sensitivity test of the two models to errors in climatic factors shows that the microphysical model was more sensitive to errors in temperature and relative humidity than the isotope inversion model. We also plot the ranges that the isotope inversion model has solutions under various meteorological and isotope inputs. The findings are useful for understanding the atmospheric processes below the cloud base and the comparability of different methods in quantifying below-cloud evaporation.
【Global and Planetary Change】Skill of isotope-enabled climate models for daily surface water vapour in East Asia
论文信息：
Shengjie Wang, Yuqing Qian, Kei Yoshimura, Hayoung Bong, Camille Risi, Zhongwang Wei, Hongxi Pang, Wei Xiao, Shijun Lei, Meng Xing, Pei Zhao, Huawu Wu, Yudong Shi, Di Wang, Mingjun Zhang*.Skill of isotope-enabled climate models for daily surface water vapour in East Asia. Global and Planetary Change, 2024, 239: 104502.
论文摘要：
The isotope-enabled general circulation models (GCM) have been widely applied to simulate the variability of stable isotopes in meteoric water at various time scales. The in-situ observations of water vapour isotopes are an important basis for assessing the performance of isotope-enabled GCMs, although they are still limited. Here we compiled the observations of near-surface water vapour isotopes on a daily scale at 17 stations in East Asia, and assessed the skill and the association between isotope error and meteorological errors on a daily scale. Generally, the spatial pattern and seasonal variability can be well simulated in the isotope-enabled GCMs. The models show better skill for warm and humid backgrounds, which also corresponds to the monsoonal regions with lower latitudes in East Asia. As spatial resolution is finer, the skill of models is better, which can be seen from the two GCMs. According to the correlation coefficient, the improvement of resolution is more obvious in summer than in winter, especially for IsoGSM. In addition, the correlation coefficient in winter is usually larger than that in summer. The daily modelling has good potential to investigate the daily or synoptic climate information in water isotopes. The findings are useful for understanding the applicability of isotope-enabled models in East Asia and the climate factors influencing the skill of isotope-enabled models on a daily basis.
【Journal of Forestry Research】Radial growth in Qinghai spruce is most sensitive to severe drought in the Qilian Mountains of Northwest China
论文信息：
Wang, Xuge, Jiao, Liang, Xue, Ruhong, Zhang, Peng, Du, Dashi, Wei, Mengyuan, Li, Qian. Radial growth in Qinghai spruce is most sensitive to severe drought in the Qilian Mountains of Northwest China. Journal of Forestry Research, 2024, 35: 1007-662X.
论文摘要：
Global warming and frequent extreme drought events lead to tree death and extensive forest decline, but the underlying mechanism is not clear. In drought years, cambial development is more sensitive to climate change, but in different phenological stages, the response relationship is nonlinear. Therefore, the dynamic relationship between tree radial growth and climatic/environmental factors needs to be studied. We thus continuously monitored radial growth of Qinghai spruce (Picea crassifolia Kom.) and environmental factors from January 2021 to November 2022 using point dendrometers and portable meteorological weather stations in the central area of the Qilian Mountains. The relationship and stability between the radial growth of Qinghai spruce and environmental factors were compared for different levels of drought in 2021 and 2022. The year 2022 had higher temperatures and less precipitation and was drier than 2021. Compared with 2021, the growing period in 2022 for Qinghai spruce was 10 days shorter, maximum growth rate (Grmax) was 4.5 μm·d−1slower, and the initiation of growth was 6 days later. Growth of Qinghai spruce was always restricted by drought, and the stem radial increment (SRI) was more sensitive to precipitation and air relative humidity. Seasonal changes in cumulative radial growth were divided into four phenological stages according to the time of growth onset, cessation, and maximum growth rate (Grmax) of Qinghai spruce. Stability responses of SRI to climate change were stronger in Stage 3 and Stage 4 of 2021 and stronger in Stage 1 (initiation growth stage) and Stage 3 of 2022. The results provide important information on the growth of the trees in response to drought and for specific managing forests as the climate warms.
【Science of the Total Environment】Extreme low air temperature and reduced moisture jointly inhibit respiration in alpine grassland on the Qinghai-Tibetan Plateau
Tonghong Wang, Xufeng Wang, Songlin Zhang*, Xiaoyu Song, Yang Zhang, Junlei Tan, Zhiguo Ren, Ziwei Xu, Tao Che, Yanpeng Yang, Zain Nawaz. Extreme low air temperature and reduced moisture jointly inhibit respiration in alpine grassland on the Qinghai-Tibetan Plateau. Science of the Total Environment, 2024, 927: 172039.
论文摘要：
Alpine grassland is the main vegetation on the Qinghai-Tibetan Plateau (QTP) and exhibits high sensitivity to extreme weather events. With global warming, extreme weather events are projected to become more frequent on the QTP. However, the impact of these extreme weather events on the carbon cycle of alpine grassland remains unclear. The long-term in-situ carbon fluxes data was collected from 2013 to 2022 at an alpine grassland site to examine the impact of extreme low air temperature (ELT) and reduced moisture (including air and soil) on carbon fluxes during the growing season. Our findings indicated that a significant increase in net ecosystem production (NEP) after 2019, with the average NEP increasing from 278.91 ± 43.27 g C m−2 year−1 during 2013–2018 to 415.45 ± 45.29 g C m−2 year−1 during 2019–2022. The ecosystem carbon use efficiency (CUE) increased from 0.38 ± 0.06 during 2013–2018 to 0.62 ± 0.11 during 2019–2022. By combining concurrently measured environmental factors and remote sensing data, we identified the factors responsible for the abrupt change in the NEP after 2019. This phenomenon was caused by an abrupt decrease in ecosystem respiration (Reco) after 2019, which resulted from the inhibition imposed by ELT and reduced moisture. In contrast, gross primary production (GPP) remained stable from 2013 to 2022, which was confirmed by the remotely sensed vegetation index. This study highlights that combined extreme weather events associated with climate change can significantly impact the NEP of alpine grassland, potentially affecting different carbon fluxes at different rates. These findings provide new insights into the mechanisms governing the carbon cycle of alpine grassland.
【Forest Ecology and Management】Different resource allocation strategies of two dominant conifer species to the heterogeneous environments in the Qinghai-Tibet Plateau
论文信息：
Jingjing Wu, Liang Jiao*, Xuli Zhu, Xichen Che, Xin Yuan, Kuan Zhang, Yarong Qin. Different resource allocation strategies of two dominant conifer species to the heterogeneous environments in the Qinghai-Tibet Plateau. Forest Ecology and Management, 2024, 563: 121986.
论文摘要：
Understanding the resource allocation strategies of dominant conifer species in mountain forest ecosystem can provide decision-making basis for mountain ecosystem conservation and sustainable use. However, the resource allocation trade-offs of different tree species under the heterogeneous environments in arid and semi-arid mountains were not fully understood. Therefore, we analyzed the stoichiometric characteristics of two dominant conifer species in the Qilian Mountains at the eastern margin of the Tibetan Plateau with three altitudes and four typical regions to explore the resource allocation strategies of ecological adaptations of dominant tree species under different environmental gradients. The results showed that there were differences in stoichiometric characteristics for different tree species, altitudes and regions. 1) Compared with Qinghai spruce, Qilian juniper stored more nutrients in the underground part when it was resistant to drought. 2) Plants tended to invest more N and P to compensate for reduced physiological efficiency as altitude increases and temperatures decrease. 3) Different dominant conifer species stored more nutrients in the roots in the western section under drought stress. However, in the eastern section with favorable moisture and temperature they invested nutrients in the leaves and stems. 4) Mean annual temperature (MAT), mean annual precipitation (MAP) and soil water content (SWC) were the common controlling factors affecting stoichiometric characteristics of the different tree species, altitudes and regions. The findings of this study provided a theoretical basis for understanding of plant adaptation mechanisms at different spatial and temporal scales and species effects, as well as technical support for forest ecological control and restoration in ecologically sensitive and fragile areas.
【SCIENCE OF THE TOTAL ENVIRONMENT】Water pollution scenarios and response options for China
论文信息：
Haoyuan Feng*, Joep F. Schyns, Maarten S. Krol, Mengjie Yang, Han Su, Yaoyi Liu, Yongpeng Lv, Xuebin Zhang, Kai Yang, Yue Che. Water pollution scenarios and response options for China. SCIENCE OF THE TOTAL ENVIRONMENT, 2024, 914: 169807.
论文摘要：
China has formulated several policies to alleviate the water pollution load, but few studies have quantitatively analyzed their impacts on future water pollution loads in China. Based on grey water footprint (GWF) assessment and scenario simulation, we analyze the water pollution (including COD, NH3-N, TN and TP) in China from 2021 to 2035 under different scenarios for three areas: consumption-side, production-side and terminal treatment. We find that under the current policy scenario, the GWF of COD, NH3-N, TN, and TP in China could be reduced by 15.0 % to 39.9 %; the most effective measures for GWF reduction are diet structure change (in the consumption-side area), and the wastewater treatment rate and livestock manure utilization improvement (in the terminal treatment area). However, the GWF will still increase in 8 provinces, indicating that the current implemented policy is not universally effective in reducing GWF across all provinces. Under the technical improvement scenario, the GWF of the four pollutants will decrease by 54.9 %–71.1 % via improvements in the current measures related to current policies and new measures in the production-side area and the terminal treatment area; thus, GWF reduction is possible in all 31 provinces. However, some policies face significant challenges in achieving full implementation, and certain policies are only applicable to a subset of provinces. Our detailed analysis of future water pollution scenarios and response options to reduce pollution loads can help to inform the protection of freshwater resources in China and quantitatively assess the effectiveness of policies in other fields.
【Agricultural and Forest Meteorology】Grassland biomass allocation across continents and grazing practies and its response to climate and altitude
论文信息：
Jianjun Cao, Yumei Li, Asim Biswas, Nicholas M. Holden, Jan F. Adamowski, Fengchu Wang, Shuyan Hong, Yanyan Qin*. Grassland biomass allocation across continents and grazing practies and its response to climate and altitude. Agricultural and Forest Meteorology, 2024, 356: 110176.
论文摘要：
Biomass allocation in grasslands is key to understanding plant response to environmental changes and grazing management. Yet, global studies on how this split between above-ground and below-ground biomass varies across continents and grazing practices are notably scarce. We employ a comprehensive field-oriented grassland database to examine differences in total net primary productivity (TNPP), above-ground net primary productivity (ANPP), below-ground net primary productivity (BNPP), and the BNPP to ANPP ratio across continents and between grazed and non-grazed grasslands. Oceania showed the greatest ANPP (916 g·m−2·a−1), while Asia had the lowest (192 g·m−2·a−1). BNPP values were similar among Oceania, Africa, and Asia (~600 g·m−2·a−1), significantly exceeding those in Europe (289 g·m−2·a−1) and North America (408 g·m−2·a−1). South America, Africa, and Oceania had the highest TNPP (around 1418 g·m−2·a−1 to 1466 g·m−2·a−1), while Europe had the lowest TNPP (344 g·m−2·a−1). The BNPP to ANPP ratio was highest in South America (4.17) and Asia (3.46). Global differences in TNPP and BNPP between grazed and non-grazed grasslands were minimal, but ANPP (169 g·m−2·a−1 and 198 g·m−2·a−1, respectively) and the BNPP to ANPP ratio (4.87 and 2.40, respectively) differed significantly. Across continents and grazing practices, climate had a greater role in regulating grassland biomass allocation than altitude, and warming may have a more detrimental impact on grazed grasslands than non-grazed grasslands. Distinct biomass allocation trends under various continental and grazing conditions exert effects on the economic and ecological functions of grasslands. Our study underscores the need for balanced grassland utilization strategies at a global scale. This involves optimizing grazing in high ANPP grasslands and protecting those with significant BNPP, thereby contributing to a sustainable and ecologically sound use of grasslands in the future.
【Journal of Cleaner Production】A context-dependent response of soil carbon and nitrogen to grazing exclusion: An evidence from a global meta-analysis
论文信息：
Jianjun Cao, Luyao Wang, Jan F. Adamowski, Asim Biswas, Mohammad Reza Alizadeh, Qi Feng*. A context-dependent response of soil carbon and nitrogen to grazing exclusion: An evidence from a global meta-analysis. Journal of Cleaner Production, 2024, 434: 139792.
论文摘要：
Grazing exclusion (GE) is commonly used worldwide in the management of degraded grasslands. While the effects of GE on soil organic carbon (SOC) and soil total nitrogen (STN) are intensively studied, little consensus has emerged due to highly variable background conditions. Drawing on 4081 observations from over 200 experiments worldwide, we applied a hierarchical meta-analysis to evaluate the effect of GE on SOC and STN. Overall, GE significantly increased SOC (14.74%) and STN (28.75%) compared to traditional grazing. However, the effect was mainly dependent on GE duration, site elevation and the mean annual precipitation. The improvement in SOC and STN were greatest when the duration of GE exceeded 10 years and the mean annual temperature, precipitation and elevation ranged between 0°C and 10 °C, less than or equal to 300 mm, and 1500 m–2500 m, respectively. In temperate and desert grasslands, long-term GE (>10 years) improved SOC and STN, whereas in meadow grasslands, short-term GE (≤5 years) contributed the most to their improvement. Long-term GE (>10 years) had a significant positive effect on SOC and STN in historically lightly and heavily grazed areas, but not in historically moderately grazed areas. As the response of SOC and STN under GE duration can vary from positive to negative based on different conditions, an appropriate GE duration implementation strategy should be developed in a context-dependent manner during future restoration of degraded grasslands.
【Soil & Tillage Research】Response of leaf, litter, and root ecological stoichiometries to grazing exclosure duration on the Qinghai-Tibetan Plateau
论文信息：
Jiabao Cui, Yumei Li, Jan F. Adamowski, Jianjun Cao*, Asim Biswas, Jiwei Wang, Xiaofang Zhang. Response of leaf, litter, and root ecological stoichiometries to grazing exclosure duration on the Qinghai-Tibetan Plateau. Soil & Tillage Research, 2024, 241: 106123.
论文摘要：
To understand the intricacies of nutrient cycling and advance grassland restoration strategies, this study delves into the varying responses of leaf, litter, and root ecological stoichiometries to different durations of grazing exclosure (GE) on the ecologically vital Qinghai-Tibetan Plateau in eastern China. The investigation encompassed GE durations of 0 (seasonal grazing), 13, 22, and 39 years, revealing pivotal alterations in ecological stoichiometries. Notably, GE markedly augmented leaf and root carbon (C) levels and the carbon to nitrogen (C:N) ratio, while diminishing leaf and root nitrogen (N), and root N to phosphorus (N:P) ratios. Intriguingly, with prolonged GE, root C and C:N exhibited a minor decline, and root N slightly increased, albeit remaining significantly lower than in seasonally grazed areas. Leaf N, along with litter P, C:P, and N:P ratios, displayed remarkable stability over time. This suggests that ecological stoichiometries of different plant components responded differently to GE duration. Across plant components, soil NH 4 + N emerged as a predominant factor influencing their stoichiometries, underscoring the complex interplay between vegetation and soil. There was the interconnectedness of C, N, and P among leaf, litter, and roots, highlighting understanding of these elements’ cycles. This research, the first of its kind to assess the impact of extensive GE durations on leaf, litter, and root ecological stoichiometries on the Qinghai-Tibetan Plateau, offers insights for understanding ecological stoichiometries at the ecosystem level or between the above-ground part and below-ground part and for alpine grassland management.
【Science of The Total Environment】Wet events increase tree growth recovery after different drought intensities
论文信息：
Peng Zhang, Liang Jiao*, Ruhong Xue, Mengyuan Wei, Xuge Wang, Qian Li. Wet events increase tree growth recovery after different drought intensities. Science of The Total Environment, 2024, 924: 171595.
论文摘要：
Understanding the dynamics of tree recovery after drought is critical for predicting the state of tree growth in the context of future climate change. While there has been a great deal of researches showing that drought events can cause numerous significant negative effects on tree growth, the positive effects of post-drought wetting events on tree growth remain unclear. Therefore, we analyzed the effect of wet and dry events on the radial growth of trees in Central Asia using data on the width of tree rings. The results showed that 1) Drought is the main limiting factor for radial growth of trees in Central Asia, and that as the intensity and sensitivity of drought increases, tree resistance decreases and recovery rises, and more frequent droughts reduce tree resistance. 2) Tree radial growth varied significantly with wet and dry conditions, with wet events before and after drought events significantly enhancing tree radial growth. 3) When drought is followed by a wetting event, the relationship between tree resistance and recovery is closer to the line of full resilience, with a significant increase in recovery, and compensatory growth is more likely to occur. Thus, wetting events have a significant positive effect on tree radial growth and are a key factor in rapid tree growth recovery after drought.
【Science of the Total Environment】Identifying carbon sequestration’s priority supply areas from the standpoint of ecosystem service flow: A case study for Northwestern China’s Shiyang River Basin
论文信息：
Jia Liang, Jinghu Pan*. Identifying carbon sequestration’s priority supply areas from the standpoint of ecosystem service flow: A case study for Northwestern China’s Shiyang River Basin. Science of the Total Environment, 2024, 927: 172283.
论文摘要：
Finding important supply areas helps maintain the ecological security of the region and promotes the creation of healthy ecosystems. By considering the ecosystem service flows (ESF), priority provisioning area studies can be approached from a new perspective. This study describes the real supply in terms of flows. The goal was to reveal the priority-ranked supply pattern of ecosystem carbon sequestration services (ECSS) in the Shiyang River Basin (SRB). First and foremost, soil respiration models and Carnegie-Ames-Stanford Approach (CASA) model were used to examine the supply of ECSS, and a combination of natural and human factors was used to determine the demand for ECSS. Second, Python was used to illustrate the ECSS flow trajectories and flows. Lastly, and utilized in conjunction with System Conservation Planning (SCP) to determine supply regions of importance. The results show that, first, the spatial distribution of ECSS supply and demand clearly demonstrates heterogeneity. This is reflected in the spatial characteristics of supply, which are “high in the south and low in the north,” and demand, which is “high in the urban areas and low in the suburbs.” Second, the middle and lower portions of the basin, where there is little precipitation and little vegetation, are home to the majority of the locations with poor carbon sequestration fluxes. These areas accounted for almost 60 % of the entire watershed area over time. Third, the first priority area of ECSS occupies 19.3 % of the basin's total area, while the second priority area occupies 21.46 %. For the major supply regions, strict ecological protection laws must be implemented going forward in order to ensure the ability to sustain ECSS supply. The long-term growth of SRB as well as ecological and environmental management can benefit from this research's foundational role in policymaking.
【Earth system science data】Dataset of stable isotopes of precipitation in the Eurasian continent
论文信息：
Longhu Chen, Qinqin Wang, Guofeng Zhu*, Xinrui Lin, Dongdong Qiu, Yinying Jiao, Siyu Lu, Rui Li, Gaojia Meng, Yuhao Wang. Dataset of stable isotopes of precipitation in the Eurasian continent. Earth system science data, 2024, 16: 1543-1557.
论文摘要：
Stable isotopes in precipitation can effectively reveal the process of atmospheric water circulation, serving as an effective tool for hydrological and water resource research, climate change, and ecosystem studies. The scarcity of stable isotope data in precipitation has hindered comprehension of the regional hydrology, climate, and ecology due to discontinuities on a temporal scale and unevenness on a spatial scale. To this end, we collated stable hydrogen and oxygen isotope data in precipitation from 842 stations in Eurasia from 1961 to 2022, totalling 51 752 data records. Stable isotopes in precipitation across various regions of Eurasia, as a whole, decrease with increasing latitude and distance from the coast. In the summer, stable isotopes in precipitation are relatively enriched, while in the winter, they are relatively depleted. In recent decades, the stable isotope values of Eurasian precipitation show an overall trend of increasing variation with the advancement of years, which is associated with global warming. Geographical location, underlying surface conditions, seasons, and atmospheric circulation are all factors that determine the characteristics of stable isotopes in precipitation. The dataset of stable isotopes in Eurasian precipitation provides a powerful tool for understanding changes in regional atmospheric water circulation and assists in conducting hydrological, meteorological, and ecological studies in related regions. The datasets are available at https://doi.org/10.17632/rbn35yrbd2.2 (Zhu, 2024).
【Journal of Environmental Management】Estimation of carbon emissions from different industrial categories integrated nighttime light and POI data—a case study in the yellow river basin
论文信息：
Wei Wei, Dibo Chen*, Xing Zhang, Libang Ma, Binbin Xie, Junju Zhou, Mintong Wang, Xiaoxu Wei, Shilong Yang, Peng Yan. Estimation of carbon emissions from different industrial categories integrated nighttime light and POI data—a case study in the yellow river basin. Journal of Environmental Management, 2024, 370: 122418.
论文摘要：
Global industrial activities contribute significantly to carbon emissions, impacting climate change and necessitating innovative methods for precise emission monitoring and management at both regional and international levels. Based on nighttime light data, POI data, land use data and energy statistics, this study calculated the carbon emissions of different industrial categories in the Yellow River Basin from 2005 to 2020 and analyzed the temporal and spatial characteristics of their changes to reveal the carbon emission patterns of different industrial categories in the basin. This study analyzes the carbon emissions of various industrial categories from a spatial perspective, addressing the limitations of traditional industrial carbon emission assessments at the spatial scale. The results showed that although the growth rate of industrial carbon emissions in the Yellow River Basin has slowed down significantly, it has not yet reached the peak, with the carbon emissions increasing from 400,0647t in 2005 to 519,216,200t in 2020. The mechanical and electronic manufacturing industry had the largest carbon emissions, which accounting for 37.08% of the total carbon emissions. Medical pharmaceuticals had the fewest, only accounting for 1.16% of the total carbon emissions. The spatial distribution of carbon emissions showed a cluster distribution, and the emissions gradually decrease from the center to the periphery. In addition, the carbon emissions of the construction industry, medical pharmaceutical industry and mechanical and electronic manufacturing industry were concentrated in and around the cites, and were closely related to urban development, infrastructure and technological progress. Furthermore, the study reveals that the relationship between carbon emissions and population structure across different industrial categories is complex. A stable relationship exists between carbon emissions and the population within the mechanical and electronic manufacturing, metallurgy, and chemical industries. However, for the clothing, furniture, and pharmaceutical industries, population is not the sole influencing factor on their carbon emissions. This study provides a new perspective on low-carbon green and sustainable development strategies for industrial carbon emissions in the Yellow River Basin, and emphasizes the importance of constructing detailed, diversified and innovative management strategies in the face of climate change challenges.
【Health and Place】The transmission network and spatial-temporal distributions of COVID-19: A case study in Lanzhou, China
论文信息：
Liangjie Yang*, Xiao Yu, Yongchun Yang, Ya Ling Luo, Lingling Zhang. The transmission network and spatial-temporal distributions of COVID-19: A case study in Lanzhou, China. Health and Place, 2024, 86: 103207.
论文摘要：
Public emergencies exert substantial adverse effects on the socioeconomic development of cities. Investigating the transmission characteristics of COVID-19 can lead to evidence-based strategies for future pandemic intervention and prevention. Drawing upon primary COVID-19 data collected at both the street level and from individuals with confirmed cases in Lanzhou, China, our study examined the spatial-temporal distribution of the pandemic at a detailed level. First, we constructed transmission networks based on social relationships and spatial behavior to elucidate the actual natural transmission chain of COVID-19. We then analyze key information regarding pandemic spread, such as superspreaders, superspreading places, and peak hours. Furthermore, we constructed a space-time path model to deduce the spatial transmission trajectory of the pandemic while validating it with real activity trajectory data from confirmed cases. Finally, we investigate the impacts of pandemic prevention and control policies. The progression of the pandemic exhibits distinct stages and spatial clustering characteristics. People with complex social relationships and daily life trajectories and places with high pedestrian flow and commercial activity venues are prone to becoming superspreaders and superspreading places. The transmission path of the pandemic showed a pattern of short-distance and adjacent transmission, with most areas not affected. Early-stage control measures effectively disrupt transmission hotspots and impede the spatiotemporal trajectory of pandemic propagation, thereby enhancing the efficacy of prevention and control efforts. These findings elucidate the characteristics and transmission processes underlying pandemics, facilitating targeted and adaptable policy formulation to shape sustainable and resilient cities.
【Ecological Indicators】Construction and stability evaluation of ecological networks in the Loess Plateau
论文信息：
Liangjie Yang, Fangning Zhang, Lishuang Qin. Construction and stability evaluation of ecological networks in the Loess Plateau. Ecological Indicators, 2024, 159: 111697.
论文摘要：
Enhanced and optimized ecological security patterns in ecologically fragile areas are conducive to promoting their sustainable development. A valuable strategy for achieving multi-dimensional coexistence and stability of regional functions is constructing ecological networks and optimizing them. Given its susceptibility to human activities and climate change, enhancing the ecological security pattern of the Loess Plateau is particularly crucial. This study selects nine indicators from natural and human activity perspectives and constructs an ecological network using MCR and gravity models. Then, complex network analysis is performed to examine the ecological network topology and stability under deliberate attacks and random failures in the Loess Plateau. The results indicate that ecological sources are primarily located in the central and northern regions of the Loess Plateau, and the links adhere to the proximity effect theory, displaying an inverse relationship with the spatial distance separating the sources. Both preferential attachment and a power-law distribution are observed in the degree distribution of the ecological network. Additionally, deliberate attacks and random fault simulations lead to a significant decrease in both connectivity and transmission efficiency of the ecological network. The failure of hub nodes exerts a diverse range of influences on the ecological network. This study enhances our understanding of ecosystem interactions and presents crucial insights for ecological conservation and restoration strategies.
【Ecological Indicators】Evaluation of alpine wetland ecological degradation based on alpine wetland degradation index: A case study in the first meander of the Yellow River
论文信息：
Ruifeng Zhao, Jingfa Wang, Linghui Li, Lihua Zhang, Haitian Lu, Xiaoyu Jiang, Xidong Chen, Ziyi Han, Cairang Dang-zhi, Hong Wang, Lamao Yang-jian. Evaluation of alpine wetland ecological degradation based on alpine wetland degradation index: A case study in the first meander of the Yellow River. Ecological Indicators, 2024, 158: 111414.
论文摘要：
The alpine wetlands are vital in regulating climate, maintaining biodiversity, stabilizing ecosystem balance, maintaining water resources and ecological security. However, influenced by extreme climate and human activities, the ecological degradation of alpine wetlands seriously threatens the sustainable development of the region. Nowadays, it is urgent to develop an ecological monitoring index suitable for high-altitude alpine wetlands, and timely carry out long-term remote sensing monitoring and evaluation on the ecological degradation and restoration of alpine wetlands. Based on Landsat images of Google Earth Engine (GEE) year by year, we constructed the Alpine Wetland Degradation Index (AWDI) and studied the ecological change process of alpine wetland in the first meander of the Yellow River during 1990–2022 with the help of the Unary linear regression, the Theil-Sen median and the Mann-Kendall test methods. In addition, we also discussed the main driving factors of ecological degradation of alpine wetlands with the help of the Pearson correlation analysis and Geodetector. Our research found that the AWDI based on long-time series MNDWI, NDVI, FVC and WET has significant accuracy in evaluating the ecological degradation of alpine wetlands (POA= 95.69 %, Kappa = 0.9460). In the past 33 years, the ecological situation of the alpine wetland in the first meander of the Yellow River has experienced a process of degradation first and then improvement. Precipitation is the main factor that affects the ecological change of the alpine wetland, and the role of human activities can not be ignored. Our AWDI can quickly and accurately reveal the ecological degradation process of alpine wetlands, and then provide a scientific basis and case reference for the evaluation, restoration, management and protection of alpine wetland degradation.
【地理学报】植被对气候变化响应的地形调控作用
论文信息：
熊雪婷, 李传华*, 陈佳豪. 植被对气候变化响应的地形调控作用. 地理学报, 2023. 78(9): 2256-2270.
论文摘要：
地形很大程度上导致了区域气候变化的空间异质性，从而影响植被对气候变化的响应。本文以青藏高原三江源地区为研究区，利用结构方程模型，探讨地形因子通过气温、降水对归一化差值植被指数的调控作用。研究表明：三江源地区坡度、坡向主要通过调控降水影响植被对气候变化的响应，而海拔主要通过调控气温影响植被对气候变化的响应。海拔的影响最大，其减缓了植被对气候变化的响应，总效应为-0.35；坡度次之，其加剧了植被对气候变化的响应，总效应为0.31；坡向的调控作用最小，总效应为0.03；地形因子的总影响为-0.01，即3类地形因子具有抵消效应。三江源地区在坡度5°～15°、阴坡和海拔3000～3500 m的条件下，地形因子对植被的调控作用最大，其效应分别为0.23、0.08和0.39。在坡度5°～15°和海拔4500～5000 m时，坡向通过调控降水使得植被对气候变化的响应最大；在坡度5°～15°、阴坡和海拔小于4000m时，海拔通过调控气温加剧植被对气候的响应，在海拔大于4000 m时，海拔主要通过调控降水来减缓植被对气候的响应。本文可为山区植被对气候变化响应规律的研究提供基础。
【地理学报】基于腾讯迁徙大数据的中国城市网络研究
论文信息：
王录仓*, 刘海洋, 刘清. 基于腾讯迁徙大数据的中国城市网络研究. 地理学报, 2021: 76(4): 853-869.
论文摘要：
随着经济全球化和区域一体化的快速发展,城市间的交流日益密切,要素的流动性和互赖性促进了城市网络的形成,并成为一种新的区域组织模式和空间结构。本文基于2018年腾讯人口迁徙数据,构建了372×372关系数据矩阵,并从不同交通方式出发,系统刻画了中国城市网络格局。研究表明:(1)网络关联度高的城市主要集中在胡焕庸线以东区域,尤其是长三角、珠三角、京津冀、成渝等城市群地区的聚集程度最高,成为中国城市网络格局的主控力量;而西北半壁的城市处于被支配地位。(2)依据迁徙量,将中国城市网络划分为国家级、大区级、区域级、地方级和基座级网络。城市网络结构随交通方式而变化,当网络等级下移时,节点城市趋于增多,网络密度加大,但网络范围趋于缩小,网络等级与迁徙路径存在着密切的关联性,国家级网络与空运相关,区域级网络与铁路运输相呼应,地方级网络与汽车运输相关。(3)不同运输方式的经济时空距离决定了网络结构,是引致网络随路径不同而产生分异的基本因素。
【地理学报】中国能源碳足迹时空格局演化及脱钩效应
论文信息：
潘竟虎*, 张永年. 中国能源碳足迹时空格局演化及脱钩效应. 地理学报, .2021: 76(01): 206-222.
论文摘要：
利用 DMSP-OLS 夜间灯光数据和碳排放统计数据，构建碳排放面板数据模型，模拟了2000—2013 年中国的碳排放量。运用探索性时空数据分析（ESTDA）框架体系，从时空交互视角分析 2001—2013 年碳足迹的空间格局和时空依赖动态演化；利用改进的Tapio脱钩模型对 3个时间段 336 个地级单元环境碳负荷与经济增长之间的脱钩效应进行综合分析。研究表明：① 2000—2013 年，中国的碳排放在时空演变上既表现出稳中有进的总体特征，也存在快速增长的阶段特征。② 碳足迹和碳赤字均呈逐年增长趋势，年均增长率分别为4.82%和5.72%；碳足迹和碳赤字整体北方大于南方，不同的行政单元尺度下碳足迹和碳赤字空间异质性特征明显。各地级单元碳足迹变异系数逐步增大，存在极为显著的空间自相关特征。③ LISA 时间路径相对长度北方大于南方，且呈由沿海地区向中西部地区递增的趋势；LISA时间路径弯曲度整体上则由沿海地区向内陆地区递减。④ 综合脱钩指数整体以弱脱钩型为主，但弱脱钩型城市数量持续减少，扩张连接、扩张负脱钩区域数量逐渐增多且向中西部及东北地区聚集分布；全国平均脱钩弹性值逐步增长，变异系数持续下降。
【地理学报】中国地级及以上城市网络结构韧性测度
论文信息：
魏石梅, 潘竟虎*. 中国地级及以上城市网络结构韧性测度. 地理学报, 2023: 76(06): 1394-1407.
论文摘要：
随着城市间关系趋向于网络化发展以及外部急性冲击和慢性压力的增加,城市网络结构韧性作为衡量区域韧性的重要手段,致力于评估城市网络系统在面对突发故障或扰动时,能够抵御、吸收和恢复原有网络特征和重要功能的能力。以中国346个地级及以上城市为研究对象,采用2017年百度指数、腾讯人口迁徙大数据等,在构建信息、交通、经济和综合城市联系网络的基础上,从城市节点和网络层面对其层级性和匹配性进行测度,并对中断场景下网络的传输性和多样性进行分析,进而针对各网络从不同视角提出网络结构优化策略和建议。结果表明:(1) 2017年中国346个地级及以上城市的信息、交通、经济和综合联系网络整体上呈现以胡焕庸线为界的东密西疏的分布格局,但空间结构各有特点。(2)信息、交通和经济三大网络的层级性排名依次为经济>信息>交通网络。大城市及省会城市因其信息技术的快速创新与传播、产业经济的高度发展与集聚及交通基础设施的快速配备与完善在网络中具有更高的层级。(3)信息、交通、经济三大网络均具有异配性特征。信息网络中高权重节点与低权重节点间的跨区域交流机会更多,因而具有最高的异配韧性。(4)信息网络的传输与多样韧性稍高于经济网络,远高于交通网络。同一城市节点的故障或中断在影响网络传输性的同时,也会累及网络的多样性.
【地理学报】黄土高原生态系统服务供需关系的时空变化
论文信息：
赵雪雁*, 马平易, 李文青, 杜昱璇. 黄土高原生态系统服务供需关系的时空变化. 地理学报, 2021: 76(11): 2780-2796.
论文摘要：
明晰生态系统服务供需匹配关系,对实现区域生态安全与社会经济可持续发展具有重要推动作用。本文以黄土高原为案例区,应用InVEST模型、ArcGIS、GeoDA等分析工具,分析黄土高原粮食供应、水源涵养、碳固存、土壤保持等服务的供需量及其匹配关系的时空变化,旨在为黄土高原国土空间格局优化提供决策依据。结果表明:1990—2018年,（1）黄土高原除水源涵养服务供给量外,其他生态系统服务供需量均呈上升趋势,且各生态系统服务供给量及土壤保持服务需求量均呈东南高、西北低的分布特征,而粮食供应、水源涵养、碳固存服务需求量呈四周高、中间低的分布特征;（2）各类生态系统服务供需比均呈下降趋势。空间分布上,粮食供应、碳固存服务在黄土高原四周人口密集区供不应求,而其他区域供大于求;水源涵养服务在该区西北部供不应求,但东南部供大于求;土壤保持服务供不应求区集中于鄂尔多斯高原及海北州北部;（3）各类生态系统服务供需均以低低空间匹配为主;（4）粮食供应、水源涵养、碳固存服务供需比的空间分布均以高高集聚为主,而土壤保持服务以低低集聚和高高集聚为主。除土壤保持服务供需比的空间集聚性有所增强外,其他生态系统服务均呈减弱趋势。
【地理学报】河湟地区乡村聚落位序累积规模模型的实证研究
黄万状, 石培基*. 河湟地区乡村聚落位序累积规模模型的实证研究. 地理学报, 2021: 76(06): 1489-1503.
论文摘要：
科学确定乡村聚落体系是落实乡村振兴战略和促进农业农村现代化的关键之一,研究乡村聚落规模分布规律有助于乡村聚落体系优化。基于理论假设推导出了位序累计规模模型的准确表达及其规律,在此基础上,比较研究了位序累计规模模型和乡村位序—规模法则在河湟地区的适用性和准确性,厘清了河湟地区乡村聚落规模分布的特征和演变规律。研究显示:（1）位序累积规模模型是一个单调递增的凹函数（P≥1）,函数表达式随着聚落规模分布的帕累托系数变化而变化。当1≤Pi）+b,拟合系数a与首位聚落规模呈正相关;当P≥1.20225时,S=bealn（Ni）,聚落规模变异系数和首位聚落规模与拟合系数a呈负相关关系,而与拟合系数b则呈正相关关系。（2）位序累积规模模型在河湟地区乡村聚落规模分布研究中具有良好的适用性和准确性,而乡村位序—规模法则不适用。（3）河湟地区乡村聚落规模分布为接近于帕累托系数为2的均衡分布且总体趋于集聚。未来河湟地区应有序推进乡村聚落向自然和社会经济条件较为优越区域适度集聚,合理制定区域乡村聚落布点规划和实用性村庄规划,走人与自然和谐共生、城乡融合发展的具有河湟地区特色的乡村振兴道路。
【地理学报】祁连山冰川服务价值评估及其时空特征
论文信息：
孙美平*, 马维谦, 姚晓军, 张明军, 李忠勤, 秦大河. 祁连山冰川服务价值评估及其时空特征. 地理学报, 2021: 76(01): 178-190.
论文摘要：
冰川为干旱区人类福祉和社会经济发展提供必不可少的资源与服务,开展冰川服务价值评估及时空特征研究对于区域社会经济可持续发展和环境保护具有重要意义。基于祁连山第一次和第二次冰川编目数据,通过构建冰川服务价值评估体系,并结合单位面积服务价格法、价值当量因子法和冰川服务价值变化指数等方法,评估祁连山冰川服务价值及时空变化。结果表明:①2016年祁连山冰川服务价值为243.54亿元,气候调节和径流调节构成该地区冰川最主要的服务,其次是淡水资源供给和水力发电,四者分别占总价值的60.58%、33.14%、3.47%和1.75%,其他类型服务价值约为2.59亿元。②在祁连山各水系中,疏勒河流域冰川服务价值最高(77.71亿元,占31.91%),其次为哈尔腾河流域(43.21亿元,占17.74%)和北大河流域(32.81亿元,占13.47%)。在行政区划上,青海省的祁连山冰川服务价值高于甘肃省11.38亿元,其中海西蒙古族藏族自治州和酒泉市境内的冰川服务价值较高,分别为111.24亿元(占45.68%)和77.58亿元(占31.86%)。③1956—2010年期间,祁连山冰川服务价值量损失4.35亿元,且冰川服务价值变化呈现经向地带性分异规律,价值损失自西向东呈加快趋势。
【地理学报】乡村政治能人治理能力与产业融合发展的耦合关系及作用机制
论文信息：
马利邦*, 李梓妍, 王录仓, 石志浩. 乡村政治能人治理能力与产业融合发展的耦合关系及作用机制. 地理学报, 2022: 77(08): 1987-2005.
论文摘要：
乡村治理是中国治理体系的底层与基座，产业融合发展是乡村振兴的核心，也是考量乡村治理绩效的重要方面。在现行的“乡政村治”治理模式下，政治能人替代传统乡贤成为新的乡村治理主体，探究其治理能力与产业融合发展之间的耦合关系及作用机制，对实现乡村振兴战略、构建“三治合一”的治理体系具有重大而深远的意义。本文在系统检视政治能人—产业融合发展耦合关系和作用机制框架的基础上，分别建构了政治能人治理能力、乡村产业融合发展的测评指标体系，以甘肃省金昌市139个行政村为评价单元，采用地理探测器模型，揭示了治理能力与产业融合发展的耦合关系及作用机制。研究表明：（1）139个行政村中，“内生”型（En型）和“内生+嵌入”型（En-Em型）村庄分别占45.3%和54.7%，两类村庄中，内涵特征指标值差异较小，而外延指标值En-Em型村庄较En型村庄大；（2）产业融合以中低水平为主，且En-Em型村庄产业融合的基础、广度和深度以及效果均好于En型村庄；（3）单因子探测显示两类村庄乡村产业融合受外延因子的影响较内涵因子大，且En-Em型村庄较En型村庄弱；双因子交互作用探测显示内涵因子在En型村庄中的作用较En-Em型村庄强，而外延因子相反，表明嵌入型政治能人治理能力对产业融合的作用较为显著。
【地理学报】中国居民城际出行网络的空间结构特征
论文信息：
潘竟虎*, 魏石梅, 张蓉, 杨亮洁. 中国居民城际出行网络的空间结构特征. 地理学报, 2022: 77(10): 2494-2513.
论文摘要：
利用腾讯迁徙数据构建居民城际出行网络，分析了不同时段、不同交通方式下中国居民城际出行网络的空间结构特征以及主要城市群的对内、对外居民城际出行模式。研究发现，2018年中国居民城际出行网络呈“东密西疏”空间分布格局，形成以京、沪、穗—深、蓉—渝等高中心性城市为顶点的顶层跨区级“钻石型”网络结构。“春运”时段城际出行的重心相较日常出行更偏向于西南，居民城际日均出行规模亦高于其他时段，特殊节假日城际出行具有显著的空间邻近效应。不同出行方式下的出行人口、出行范围和出行交通网络差异显著，航空、铁路、公路出行分别承担国家级、区域级和地方级城际出行的人口集散。主要城市群对内出行网络呈现“核心—邻近—边缘”空间格局，以多中心双核出行模式为主，对外出行网络则呈现“跨区—邻域—地方”的格局，以单中心单核出行模式为主。
【地理学报】中国陆地生态敏感性时空演变特征
李振亚, 魏伟, 周亮, 刘春芳, 郭泽呈, 庞素菲, 张静. 中国陆地生态敏感性时空演变特征. 地理学报, 2022: 77(01): 150-163.
论文摘要：
生态敏感性作为评价区域生态环境问题的重要指标之一,对区域的生态治理与管理工作具有重要意义。本文从自然生态系统、自然—社会复合生态系统、社会生态系统等视角选取生物多样性、水热环境、土壤盐渍化、土地荒漠化、土壤侵蚀和人类干扰6个指标,运用全排列多边形图示指标法对2000—2018年间中国陆地生态敏感性进行计算,并运用格网编码法对其时空演变特征进行分析。研究结果表明:（1） 2000—2018年间中国陆地生态敏感性总体稳定,生态敏感值稳定在0.33～0.34之间;但得益于21世纪以来中国实施了一系列生态环境治理与预防工作,敏感值在2000—2018年间持续下降,表明中国陆地生态敏感性状况正在逐渐好转。（2）中国陆地生态敏感性空间异质性显著,呈现出东低西高、南低北高城区高、郊区低的空间分布格局。中国西部区域和北方区域自然环境恶劣,生态自我调节能力较差,易受外界因素的影响,而人类聚居区生态自我调节能力虽然较强,但由于人类活动强度较大,其敏感性反而较高。（3）中国陆地生态敏感性受土壤（地）环境因素影响较大,但人类干扰因素影响力也在逐年递增,这表明在经济快速发展的同时,中国的生态环境保护与治理工作仍然任重道远.
【地理学报】1.5 ka以来青藏高原东北部风沙活动增强的时空差异
论文信息：
唐道斌, 杨坤美, 曾兰华, 刘向军, 辛存林*, 徐砚田. 1.5 ka以来青藏高原东北部风沙活动增强的时空差异. 地理学报, 2023: 78(09): 2284-2298.
论文摘要：
1.5 ka以来，青藏高原东北部风沙活动增强是因气候变化还是人类活动所致，抑或二者共同作用，目前还不得而知。本文根据自然环境和人口分布将青藏高原东北部分为两个区域：I区主要包括青海湖盆地、共和盆地和河湟谷地，区内水热条件较好、人口较多；II区主要包括黄河源区和柴达木盆地，区内气候寒冷干燥、人口较少。本文归纳整理这两个区域的风成沙年龄、风沙活动记录、古气候代用指标和人类活动等相关的代用记录，分析青藏高原东北部1.5 ka以来风沙活动增强的时空差异及影响因素。结果表明：1.5 ka以来，青藏高原东北部风沙活动增强存在时空差异，I区的风沙活动在相对暖湿的1.5～1.0 ka期间显著增强，而II区的风沙活动直到1.0 ka以来才开始逐渐增强。I区的风沙活动开始增强的时间比II区早了0.5 ka。综合分析发现，人类活动增强对自然植被的破坏是I区的风沙活动增强比II区提前0.5 ka的原因。1.0ka以来Ⅱ区的风沙活动增强主要是气候变化所致。本文对1.5 ka以来青藏高原东北部风沙活动增强的时空差异的认识，可为未来全球变暖趋势下该地区的生态环境治理和风沙活动变化预测提供参考.
【地理学报】郑州7·20特大暴雨灾害对中国铁路运网的冲击过程和机制
论文信息：
刘海洋, 王录仓, 常跟应. 郑州7·20特大暴雨灾害对中国铁路运网的冲击过程和机制. 地理学报, 2024: 79(03): 617-634.
论文摘要：
特大暴雨是极端天气，其引发的洪涝灾害给社会经济带来严重损失。铁路是国民经济的大动脉，铁路枢纽既是线路连接的中枢，也是客货流集散的中心。发生在枢纽地区的特大暴雨，在网络关联效应等规律的支配下，将灾害影响通过线路向外传导并放大，从而波及整个铁路网。本文基于列车停运数据，系统分析了郑州“7·20”特大暴雨灾害对中国铁路运网的冲击过程和灾情传播机制。结果表明：（1）从冲击初期到冲击中期，中国铁路运网受冲击节点逐渐增多，停运强度从暴雨冲击中心向外围递减，停运线路从局部线路向关联网络扩散，停运网络从受冲击中心中原地区沿“米”型网络向外围蔓延；冲击末期，停运节点数量减少，停运强度降低，停运强度高值节点和停运网络从外围向暴雨冲击中心收缩。（2）不同承灾体面对同一冲击时，运网形态和结构作出的响应存在分异，高铁更敏感，其恢复力更强。（3）停运网络层级性显著，择优链接效应明显，灾情首先传导至直接关联节点和关联线路再进行扩散；层级性减弱时择优链接效应也随之减弱，集聚性降低，区域小集团数量减少，一体化程度增强，传输效率提升；层级性增强则相反。（4）由于运网的一体性、关联性、沿线传导性等特征，导致运网受灾害冲击时，不仅仅在灾害中心发生停运现象，还会涉及相关节点、线路及其关联区域。本文可为提升中国铁路运输综合防灾、减灾能力，实现安全、可靠运营提供科学依据。
【地理学报】空间污名化过程与形成机制研究
论文信息：
李巍*, 杨文, 王录仓, 漆建武, 王宗相. 空间污名化过程与形成机制研究. 地理学报, 2024: 79(06): 1449-1463.
论文摘要：
身份污名化与领土污名化研究由来已久，但对于二者之间互动关系的探讨却相对不足。本文在回溯和梳理污名化由来的基础上，试图从地理学视角探讨人—地污名化的关系，并提出空间污名化的概念，系统诠释了空间污名化的地理过程与形成机制。研究认为：（1）空间污名化是在特定的历史环境与认知水平下，施污者通过贬低地方的感知价值与身份构建，对空间及其依附的人和物进行不全面、不准确、不客观的认知过程，从而形成符号化的污名指向。（2）在地理空间格局的异质性背景下，空间污名化具有意象构建、主体分离、群体互动、空间定位以及符号化的过程，并在不同方向、距离与尺度上，形成本地或异地的直接污名化和间接污名化类型。（3）空间不平等、权利剥削与斗争、恐惧与逃避以及恋地与社会秩序是空间污名化的基础，人—地间通过感知、识别、定位与标记的复杂互动，推动污名化的空间集中与内化，这就形成了产生、传播、反应与再生产不断循环的空间污名化机制。面对普遍的空间污名化现状，解决的关键在于重建新的叙事体系，正确认识人地关系，最终在“人类命运共同体”意识的倡导下实现“去空间污名化”。
【中国科学数据】2000–2019年三江源地区冰川矢量数据集
论文信息：
张圆, 姚晓军*, 周苏刚, 张大弘. 2000–2019年三江源地区冰川矢量数据集. 中国科学数据, 2021: 06(02): 183-194.
论文摘要：
三江源地区(89°45'-102°23'E,31°39'-36°12'N)位于青藏高原中东部和青海省南部,是我国重要的水源涵养区和生态环境保护关键地区,发育在该地区的冰川是长江、黄河和澜沧江(境外称湄公河)的重要水源补给。基于Landsat TM/OLI遥感影像数据和SRTM1弧秒DEM数据,采用波段比值法并结合人工目视修订获得了该地区2000年、2010年和2019年冰川边界矢量数据,并给出了各条冰川的名称、所在山系和流域、面积、高程及遥感影像数据源等信息。本数据集包括三江源地区三期冰川边界矢量数据和2000-2019年各条冰川的面积变化数据,可作为三江源地区冰川变化和冰川水资源评估等研究的基础数据.
【中国科学数据】1977–2018年柴达木盆地冰川矢量数据集
论文信息：
周苏刚, 姚晓军*, 张圆, 张大弘, 段红玉. 1977–2018年柴达木盆地冰川矢量数据集. 中国科学数据, 2021: 06(02): 175-182.
论文摘要：
柴达木盆地(34°41′N–39°20′N,87°49′E–101°11′E)位于青藏高原东北部,地跨青海省、甘肃省和新疆维吾尔自治区三省(自治区),四周被祁连山、阿尔金山和昆仑山所环绕,为封闭的内陆盆地。盆地海拔介于2391–6826 m之间,平均海拔4615 m。柴达木盆地发育有大量现代冰川,冰川融水是盆地众多河流的重要补给源,亦是地方社会经济发展和人民生活的重要保障,因此该区域冰川变化对水资源及其合理利用具有重要影响。本数据集基于柴达木盆地1977–2018年Landsat遥感影像和ASTER GDEM高程数据,提取1977年、2002年和2018年冰川边界矢量数据,可为研究该区域冰川现状、时空分布特征、冰川变化及对气候变化响应规律提供基础数据.
【中国科学数据】2020年青海省冰川边界及长度数据集
论文信息：
薛娇, 姚晓军*, 褚馨德, 庞文龙, 张聪, 周苏刚. 2020年青海省冰川边界及长度数据集. 中国科学数据, 2022: 07(02): 131-143.
论文摘要：
青海省(31°39′–39°19′N, 89°35′–103°04′E)地处青藏高原东北部，其境内的昆仑山、唐古拉山、祁连山、阿尔金山和阿尼玛卿山等高海拔山地现代冰川普遍发育。在全球气候变暖背景下，青海省境内冰川呈现退缩态势，及时准确了解冰川规模现状是科学评价冰川变化对气候变化响应规律及合理制订水资源利用政策的基础。本数据集基于2018–2021年GF-1/2/6高分辨率遥感影像和SRTM DEM数字高程模型数据，利用深度学习和冰川中流线自动提取方法制作青海省冰川边界和长度矢量数据，精度分别为99.01%和98.89%，可反映青海省2020年冰川现状，为该地区冰川变化和气候变化等研究提供数据支持.
【科学通报】一种提高积雪深度估算精度的D-InSAR方法
论文信息：
张彦丽*, 胡嘉正, 陈刚, 马宇鹏, 赵攀. 一种提高积雪深度估算精度的D-InSAR方法. 科学通报, 2022: 67(25): 3064-3080.
论文摘要：
积雪深度（雪深）是反映积雪时空变化规律的重要参数,是全球及区域气候变化与水文循环等研究不可或缺的观测变量.差分合成孔径雷达干涉（differential interferometric synthetic aperture radar, D-In SAR）技术利用降雪前后微波穿透积雪层形成的差分干涉相位与雪深建立几何函数关系,被广泛地应用于区域小尺度雪深估算研究.然而,其估算精度受干涉像对相干性、局地地形和积雪介电常数等因素的影响.本研究基于高分辨率Sentinel-1 SAR数据,通过引入高相干系数区域、Sentinel-2光学影像、Google Earth影像和地表覆盖类型选取地面控制点优化雪深差分干涉相位解缠精度,利用卫星局地入射角和实测积雪密度降低斜距-相位关系模型经验误差,估算得到青藏高原东北部八宝河流域2021年消融期雪深时空分布,同时根据卫星同步积雪实测资料详细探讨了雪深估算误差来源.122个地面雪深实测数据（气象站点+野外测量）验证结果表明,优化后的D-In SAR差分干涉处理能提高雪深估算精度, RMSE为3.9 cm, MAPE为20.03%, R~2达到0.92.但雪深估算值总体存在低估现象（MBE%=-16.8%）,雪深最大低估误差为9.1 cm.进一步研究发现,雪深估算精度除了D-In SAR系统失相干影响因素外,还受积雪微波穿透性和剖面结构、温度及湿度等积雪参数的影响.本方法能快速监测厘米级的雪深变化,且由于积雪异质性会限制差分干涉估算雪深的能力,更适用于干燥均质的积雪层,可为D-In SAR雪深估算研究提供科学的参考依据.
【地理学报】乡村聚落与耕地共生理论模型及案例区情景模拟
论文信息：
马利邦*, 张文博, 王祥, 陈贤斐, 白静. 乡村聚落与耕地共生理论模型及案例区情景模拟. 地理学报, 2024: 79(05): 1265-1285.
论文摘要：
乡村聚落与耕地作为描述乡村发展的重要子系统，两者互利共生对于乡村可持续发展至关重要。在甘肃省环境异质性背景下，以1384个乡（镇）为研究单元，引入共生理论构建乡村聚落与耕地共生框架，构建乡村聚落、耕地、共生环境评价指标体系，借助Lotka-Volterra模型识别其共生模式。新一轮国土空间规划背景下，借助SD-FLUS耦合模型对比分析2035年惯性发展情景（BD）和规划发展情景（PD）下共生模式演变趋势。研究发现：（1） 2000—2020年甘肃省乡村聚落、耕地发展水平呈先增后减趋势，共生环境容量呈持续下降趋势；五大农业区划3个指标差异显著，河西灌溉农业区（IA）具有明显发展优势。（2） 2000—2020年甘肃省乡村聚落与耕地共生模式整体呈互利共生向互害共生转变，互利共生占比由59.80%下降至38.97%；区域间主导模式差异显著，高寒牧区（AP）、陇南山地农业区（MA）、IA以互利共生为主，陇中旱作农业区（DA）、陇东雨养农业区（RA）分别以聚落偏害、耕地偏利为主；2000—2020年各区域主导模式均趋于多元化且呈现出由互利共生向互害共生转移的发展共性。（3）不同情景下共生模式差异显著，BD情景下五大区域延续历史粗放发展模式，互利共生模式占比均持续减少，而PD情景下因共生单元、环境容量水平的提升，共生模式向互利共生进化。