期刊：
Science of The Total Environment,2023年892:164735 ISSN：0048-9697
通讯作者：
Li, J
作者机构：
[Liu, Qinhuo; Gu, Chenpeng; Dong, Yadong; Zhao, Jing; Li, Jing; Liu, Chang; Mumtaz, Faisal] Chinese Acad Sci, Aerosp Informat Res Inst, State Key Lab Remote Sensing Sci, Beijing 100101, Peoples R China.;[Liu, Qinhuo; Gu, Chenpeng; Dong, Yadong; Zhao, Jing; Li, Jing; Liu, Chang; Mumtaz, Faisal] Univ Chinese Acad Sci, Beijing 100049, Peoples R China.;[Gao, Jixi] Minist Ecol & Environm Peoples Republ China, Satellite Applicat Ctr Ecol & Environm, Beijing 100094, Peoples R China.;[Wang, Cong] Cent China Normal Univ, Sch Urban & Environm Sci, Key Lab Geog Proc Anal & Simulat Hubei Prov, Wuhan 430079, Peoples R China.
通讯机构：
[Li, J ] C;Chinese Acad Sci, Aerosp Informat Res Inst, State Key Lab Remote Sensing Sci, Beijing 100101, Peoples R China.
关键词：
Leaf area index;Eurasian Steppe (EAS);ENSO;Vegetation change
摘要：
As the most influential atmospheric oscillation on Earth, the El Niño/Southern Oscillation (ENSO) can significantly change the surface climate of the tropics and subtropics and affect the high latitudes of northern hemisphere areas through atmospheric teleconnection. The North Atlantic Oscillation (NAO) is the dominant pattern of low-frequency variability in the Northern Hemisphere. As the dominant oscillations in the Northern Hemisphere, the ENSO and NAO have been affecting the giant grassland belt in the world, the Eurasian Steppe (EAS), in recent decades. In this study, the spatio-temporal anomaly patterns of grassland growth in the EAS and their correlations with the ENSO and NAO were investigated using four long-term leaf area index (LAI) and one normalized difference vegetation index (NDVI) remote sensing products from 1982 to 2018. The driving forces of meteorological factors under the ENSO and NAO were analyzed. The results showed that grassland in the EAS has been turning green over the past 36years. Warm ENSO events or positive NAO events accompanied by increased temperature and slightly more precipitation promoted grassland growth, and cold ENSO events or negative NAO events with cooling effects over the whole EAS and uneven precipitation decreased deteriorated the EAS grassland. During the combination of warm ENSO and positive NAO events, a more severe warming effect caused more significant grassland greening. Moreover, the co-occurrence of positive NAO with cold ENSO or warm ENSO with negative NAO kept the characteristic of the decreased temperature and rainfall in cold ENSO or negative NAO events, and deteriorate the grassland more severely.
期刊：
Computers, Environment and Urban Systems,2023年100:101921 ISSN：0198-9715
通讯作者：
Anqi Lin
作者机构：
[Hao, Fanghua; Wu, Hao; Li, Yan; Liu, Lanfa; Luo, Wenting; Lin, Anqi] Cent China Normal Univ, Hubei Prov Key Lab Geog Proc Anal & Simulat, 152 Luoyu Rd, Wuhan, Peoples R China.;[Hao, Fanghua; Wu, Hao; Li, Yan; Liu, Lanfa; Luo, Wenting; Lin, Anqi] Cent China Normal Univ, Coll Urban & Environm Sci, 152 Luoyu Rd, Wuhan, Peoples R China.;[Olteanu-Raimond, Ana-Maria] Univ Gustave Eiffel, LASTIG, ENSG, IGN, St Mande, France.;[Lin, Anqi] Cent China Normal Univ, Room 318,10 Bldg,152 Luoyu Rd, Wuhan, Peoples R China.
通讯机构：
[Anqi Lin] H;Hubei Provincial Key Laboratory for Geographical Process Analysis and Simulation, Central China Normal University, 152 Luoyu Rd, Wuhan, PR China<&wdkj&>College of Urban and Environmental Sciences, Central China Normal University, 152 Luoyu Rd, Wuhan, PR China
关键词：
Urban functional zone mapping;SALT features;Ensemble learning;Volunteered geographic information
摘要：
Urban functional zone mapping is essential for providing deeper insights into urban morphology and improving urban planning. The emergence of Volunteered Geographic Information (VGI), which provides abundant semantic data, offers a great opportunity to enrich land use information extracted from remote sensing (RS) images. Taking advantage of very-high-resolution (VHR) images and VGI data, this work proposed a SATL multifeature ensemble learning framework for mapping urban functional zones that integrated 65 features from the shapes of building objects, attributes of points of interest (POIs) tags, locations of cellphone users and textures of VHR images. The dimensionality of SALT features was reduced by the autoencoder, and the compressed features were applied to train the ensemble learning model composed of multiple classifiers for optimizing the urban functional zone classification. The effectiveness of the proposed framework was tested in an urbanized region of Nanchang City. The results indicated that the SALT features considering population dynamics and building shapes are comprehensive and feasible for urban functional zone mapping. The autoencoder has been proven efficient for dimension reduction of the original SALT features as it significantly improves the classification of urban functional zones. Moreover, the ensemble learning outperforms other machine learning models in terms of the accuracy and robustness when dealing with multi-classification tasks.
摘要：
Fractional vegetation cover (FVC) has a significant role in indicating changes in ecosystems and is useful for simulating growth processes and modeling land surfaces. The fine-resolution FVC products represent detailed vegetation cover information within fine grids. However, the long revisit cycle of satellites with fine-resolution sensors and cloud contamination has resulted in poor spatial and temporal continuity. In this study, we propose to derive a spatially and temporally continuous FVC dataset by comparing multiple methods, including the data-fusion method (STARFM), curve-fitting reconstruction (S-G filtering), and deep learning prediction (Bi-LSTM). By combining Landsat and Sentinel-2 data, the integrated FVC was used to construct the initial input of fine-resolution FVC with gaps. The results showed that the FVC of gaps were estimated and time-series FVC was reconstructed. The Bi-LSTM method was the most effective and achieved the highest accuracy (R-2 = 0.857), followed by the data-fusion method (R-2 = 0.709) and curve-fitting method (R-2 = 0.705), and the optimal time step was 3. The inclusion of relevant variables in the Bi-LSTM model, including LAI, albedo, and FAPAR derived from coarse-resolution products, further reduced the RMSE from 5.022 to 2.797. By applying the optimized Bi-LSTM model to Hubei Province, a time series 30 m FVC dataset was generated, characterized by a spatial and temporal continuity. In terms of the major vegetation types in Hubei (e.g., evergreen and deciduous forests, grass, and cropland), the seasonal trends as well as the spatial details were captured by the reconstructed 30 m FVC. It was concluded that the proposed method was applicable to reconstruct the time-series FVC over a large spatial scale, and the produced fine-resolution dataset can support the data needed by many Earth system science studies.
作者机构：
[Zhu, Yuanyuan; Ao, Rongjun; Shen, Xue; Zhou, Xiaoqi; Chen, Jing; Aihemaitijiang, Yierfanjiang] Cent China Normal Univ, Key Lab Geog Proc Anal & Simulat Hubei Prov, Wuhan, Hubei, Peoples R China.;[Zhu, Yuanyuan; Ao, Rongjun; Shen, Xue; Zhou, Xiaoqi; Chen, Jing; Aihemaitijiang, Yierfanjiang] Cent China Normal Univ, Coll Urban & Environm Sci, Wuhan, Hubei, Peoples R China.
通讯机构：
[Ao, RJ ] C;Cent China Normal Univ, Key Lab Geog Proc Anal & Simulat Hubei Prov, Wuhan, Hubei, Peoples R China.;Cent China Normal Univ, Coll Urban & Environm Sci, Wuhan, Hubei, Peoples R China.
摘要：
This study introduces the principle of resilience into the study of human settlements. In this study, a comprehensive evaluation model of urban human settlements' resilience based on the provincial region of China was constructed using the Driver-Pressure-State-Impact-Response framework. The spatio-temporal evolution characteristics of urban human settlements' resilience was explored. The influencing factors were analysed by geographical detectors, and the driving mechanism was constructed. Results show that the following. (1) The resilience level of human settlements in China continued to increase, and the resilience level of each province and city changed significantly. The overall clustering effect showed a tendency to fluctuate and weaken. The distribution of cold spot areas became less and less, and the hot spots were moving from northeast China to southeast China. (2) Significant differences existed in the intensity of the impact of different indicators on the resilience system. The value of the impact factor showed an overall upward trend, and the number of key impact factors increased. (3) Improving the ability of scientific and technological innovation, accelerating the transformation and upgrading of the regional economy, increasing the training of talents and making financial inclination in scientific and technological development and industrial pollution control were all important ways for developing and maintaining the resilience of urban human settlements. This study not only introduces a new evaluation of urban human settlements from the perspective of resilience but also explores key impact indices and driving mechanisms, which provides new ideas for studying urban human settlements.
作者机构：
[Ma, Li; Ni, Yongxin; Wang, Jianwei; Lv, Xizhi; Zhang, Qiufen] Yellow River Inst Hydraul Res, Henan Key Lab Yellow Basin Ecol Protect & Restorat, Zhengzhou 450003, Peoples R China.;[Zhang, Xin; Qin, TL; Qin, Tianling] China Inst Water Resources & Hydropower Res, State Key Lab Simulat & Regulat Water Cycle River, Beijing 100038, Peoples R China.;[Ni, Yongxin] Hohai Univ, Coll Hydrol & Water Recourses, Nanjing 210098, Peoples R China.;[Nie, Hanjiang] Key Lab Geog Proc Anal & Simulat Hubei Prov, Wuhan 430079, Peoples R China.;[Nie, Hanjiang] Cent China Normal Univ, Sch Urban & Environm Sci, Wuhan 430079, Peoples R China.
通讯机构：
[Qin, TL ] C;China Inst Water Resources & Hydropower Res, State Key Lab Simulat & Regulat Water Cycle River, Beijing 100038, Peoples R China.
关键词：
distributed hydrological model;water and land resources;evapotranspiration;runoff coefficient;Sihe River Basin
摘要：
Abstract: Conflicts between humans and land use in the process of using water and conflicts between humans and water resources in the process of using land have led to an imbalance between natural ecosystems and socio-economic systems. It is difficult to understand the impact of the processes of water production and consumption on land patches and their ecological effects. A grid-type, basin-distributed hydrological model was established in this study, which was based on land-use units and coupled with groundwater modules to simulate the water production and consumption processes in different units. By combining land use and net primary productivity, the runoff coefficient and the water use efficiency (NPP/ET) of different land units were used as indicators to characterize the interaction between water and land resources. The results showed that the average runoff coefficients of cultivated land, forest land and grassland were 0.7, 0.5 and 0.9, respectively. Moreover, the average runoff coefficients of hills, plains and basins were 0.7, 0.7 and 0.8, respectively. The NPP produced by the average unit, evapotranspiration, in cultivated land, forest land and grassland was 7 (gC/(m2•a))/mm, 0.7 (gC/(m2•a))/mm and 0.2 (gC/(m2•a))/mm, respectively. These results provide quantitative scientific and technological support in favor of the comprehensive ecological management of river basins. Keywords: distributed hydrological model; water and land resources; evapotranspiration; runoff coefficient; Sihe River Basin
摘要：
Abstract This paper contributes to debates about the globalisation of higher education by providing a pioneering geographical exploration of Chinese–foreign cooperation in running transnational higher education, or TNHE, programs. Departing from widespread neoliberal and postcolonial critiques of TNHE, which tend to emphasise liberal market forces and Anglo‐American hegemony in the circulation of academic knowledge, our study examines how the Chinese state’s developmental targets, strategic policies, and political–ideological considerations have shaped the evolutionary trajectory, geographical distribution, and cross‐border connections of China’s TNHE programs. We demonstrate that the place‐based development of TNHE is mediated by governments’ interventionist policies and embedded in existing higher education regimes, especially in the context of East Asian developmental states. By maintaining a higher education system dominated by public universities and by being the ultimate examination and approval authority, the Chinese government both determines the status of TNHE in the national higher education system, constrains the typologies and sources of knowledge flows, and shapes the national landscape of TNHE development. The territorial geographies of TNHE thus reflect complicated interactions between the state and the market, the global and the local, and economic and political/cultural forces.
期刊：
Journal of Soils and Sediments,2023年23(2):880-890 ISSN：1439-0108
通讯作者：
Xiufu Shuai
作者机构：
[Shuai, Xiufu] Cent China Normal Univ, Sch Urban & Environm Sci, Hubei Prov Key Lab Geog Proc Anal & Simulat, 152 Luoyu Rd, Wuhan 430079, Hubei, Peoples R China.
通讯机构：
[Xiufu Shuai] H;Hubei Province Key Lab. for Geographical Process Analysis and Simulation, School of Urban and Environmental Science, Central China Normal Univ, Wuhan, China
摘要：
Purpose Triple-layer model (TLM) is distinct from other surface complexation models (SCMs) with the charged beta-layer between solid surface and diffuse layer. However, its structure of electrical double layer, i.e., three capacitors connected in series, produced an uncharged beta-layer according to the rule of capacitors in the electrical circuit theory. The objective of this study was to modify TLM with the development of a new structure of electrical double layer and mathematical models for the charge-potential relationships. Methods The rule of capacitors in the electrical circuit theory was used to modify the electrical double layer in TLM. Published acid-based titration experiments on goethite in KNO3 solution by Yates and Healy (J Colloid Interface Sci 52:222-228, 1975) was used to demonstrate the modified TLM. Simulation study of the modified TLM for goethite was carried out by changing pH from 4.0 to 10.0 and ionic strength of KNO3 solution from 0.001 to 0.100 mol.l(-1). Results The finite size of ions in aqueous solution determined the parallel connection of the two capacitors, which were described by the constant capacitance model (CCM) and the diffuse layer model (DLM). A new concept termed as ion size factor delta, which was governed by the radius r of hydrated ion, was proposed to quantify the percentages of surface area occupied by the CCM and DLM capacitors. A new characteristic relationship of the modified TLM was derived to be a linear relationship between net surface charge and square root of ionic strength when the surface potential was small. The experimental results verified the characteristic relationship, and the ion size factor was validated by the success in estimating the dielectric constant of the CCM capacitor and the radii of hydrated ions (K+ and NO3-). The CCM capacitor occupied 33.8% of the area of goethite surface. Simulation results showed that substantial amount of charge was at the compact layer, and it contributed 14.6% to 74.4% of the net surface charge. Conclusion New electrical double layer with structure of connection of the two capacitors in parallel eliminated the internal flaw of the classical TLM, modified the classical TLM into a general model which unified CCM and DLM, and supported the core of the classical TLM (i.e., the charged compact layer and the diffuse layer).
作者机构：
[Lei Hu] School of Remote Sensing and Information Engineering, Wuhan University, Wuhan 430079, China;Huawei Cloud & AI, Beijing 100085, China;Key Laboratory for Geographical Process Analysis & Simulation of Hubei Province, Central China Normal University, Wuhan 430079, China;College of Urban and Environmental Sciences, Central China Normal University, Wuhan 430079, China;Author to whom correspondence should be addressed.
通讯机构：
[Feifei Peng] K;Key Laboratory for Geographical Process Analysis & Simulation of Hubei Province, Central China Normal University, Wuhan 430079, China<&wdkj&>College of Urban and Environmental Sciences, Central China Normal University, Wuhan 430079, China<&wdkj&>Author to whom correspondence should be addressed.
摘要：
Semantic change detection (SCD) holds a critical place in remote sensing image interpretation, as it aims to locate changing regions and identify their associated land cover classes. Presently, post-classification techniques stand as the predominant strategy for SCD due to their simplicity and efficacy. However, these methods often overlook the intricate relationships between alterations in land cover. In this paper, we argue that comprehending the interplay of changes within land cover maps holds the key to enhancing SCD’s performance. With this insight, a Temporal-Transform Module (TTM) is designed to capture change relationships across temporal dimensions. TTM selectively aggregates features across all temporal images, enhancing the unique features of each temporal image at distinct pixels. Moreover, we build a Temporal-Transform Network (TTNet) for SCD, comprising two semantic segmentation branches and a binary change detection branch. TTM is embedded into the decoder of each semantic segmentation branch, thus enabling TTNet to obtain better land cover classification results. Experimental results on the SECOND dataset show that TTNet achieves enhanced performance when compared to other benchmark methods in the SCD task. In particular, TTNet elevates mIoU accuracy by a minimum of 1.5% in the SCD task and 3.1% in the semantic segmentation task.
作者机构：
[Li, Zhuofan] Xinyang Normal Univ, Coll Tourism, Xinyang 464000, Peoples R China.;[Li, Zhuofan] Cent China Normal Univ, Key Lab Geog Proc Anal & Simulat Hubei Prov, Wuhan 430079, Peoples R China.
关键词：
rural regional system;rural restructuring;rural transformation;Jianghan Plain in China
摘要：
Abstract: The rural decline accompanying industrialization and urbanization is a lingering puzzle in human society, while promoting rural restructuring and transformation is considered the primary task of contemporary rural development. It is the historical mission of rural geography research in the new era to scientifically understand the characteristics of contemporary rural development and accurately explain the patterns of rural reconstructing and transformation. In this paper, the Jianghan Plain in China is selected for the case study. Characteristic indexes are selected based on the “structure–function” correlation to interpret rural restructuring. Measurement benchmarks are unified through functional value marketization to interpret rural transformation. Multiple statistical analysis is adopted to identify the action paths and decipher the correlation mechanisms. The case study yields the following findings. (1) The rural restructuring on Jianghan Plain has spatial and temporal differences. Rural restructuring has roughly gone through the social restructuring-led, economic restructuring-led, and spatial restructuring-led evolution stages, showing spatially divergent patterns with high rural comprehensive restructuring index (RRC) areas concentrated around the main traffic arteries and linear low RRC areas along the Yangtze River banks. (2) Rural restructuring and transformation on Jianghan Plain show significant correlation effects. During the study period, the rural transformation magnitude (RTM) continues to increase and shows a spatial map similar to that of rural restructuring, with economic-spatial restructuring-led and economic-social restructuring-led as the main modes of rural transformation. (3) The correlation mechanism of rural restructuring and transformation on Jianghan Plain has characteristics typical of less-developed agricultural areas. The economic restructuring led by agricultural land changes and the social restructuring led by rural population outward migration remain the main paths of rural transformation, and the agricultural function still plays an important role in some rural areas. The quantitative measurement of rural region functions in this study need further optimization, and the refinement and accuracy of regional function accounting needs further exploration. The research results are expected to provide a scientific basis for stimulating rural development and promoting sustainable rural development in contemporary developing countries. Keywords: rural regional system; rural restructuring; rural transformation; Jianghan Plain in China
关键词：
Nitrogen leaching;nitrogen uptake;nitrogen use efficiency;Nitrogen balance;Paddy yield
摘要：
Nitrogen loss from paddy fields contributes to most of the nitrogen pollution load in the Ningxia Yellow River irrigation area, threatening the water quality of the Yellow River. Consequently, optimizing the nitrogen management practices in this area is essential, which can maintain paddy grain productivity and reduce nitrogen loss simultaneously. Five treatments with different nitrogen application rates and nitrogen fertilizer types were set in this study, including conventional urea application with zero nitrogen application rate (CK, 0 kg hm(-2)), nitrogen expert-based fertilization application strategy (NE, 210 kg hm(-2)), optimized nitrogen fertilizer application strategy recommended by local government (OPT, 240 kg hm(-2)), and farmer's experience-based nitrogen fertilizer application strategy (FP, 300 kg hm(-2)), and controlled-release urea application (CRU, 180 kg hm(-2)). The data from one growth season field experiment in 2021 revealed the dynamics of nitrogen concentration, paddy yield and its nitrogen uptake characteristic, and nitrogen balance in the paddy field under different nitrogen application practices. Most nitrogen leaching was observed during the seedling and tillering stages in the form of nitrate nitrogen (NO3-N). Compared with the FP, the CRU and OPT significantly reduced the nitrogen concentrations of total nitrogen (TN), ammonium nitrogen (NH4+-N), and NO3-N in the surface and soil water and reduced the nitrogen leaching at 100 cm soil depth. Meanwhile, the paddy grain yield in CRU (7737 kg hm(-2)) and OPT (7379 kg hm(-2)) was not significantly decreased compared with FP (7918 kg hm(-2)), even though the nitrogen uptake by grain and straw was higher in FP (135 kg hm(-2)) than in other treatments (52.10 similar to 126.40 kg hm(-2)). However, the grain yield in NE (6972 kg hm(-2)) was decreased compared with the FP. The differences in grain yield among these treatments were mainly attributed to the ear number and grain number changes. Also, the highest nitrogen use efficiency (40.14%), apparent nitrogen efficiency (19.53 kg kg(-1)), and nitrogen partial productivity (43.98 kg kg(-1)) were identified in CRU than in other treatments. Considering increased grain yield and reducing nitrogen loss in the paddy field simultaneously, the treatments of CRU (i.e., 180 kg hm(-2) nitrogen application rate with controlled-release urea) and OPT (i.e., 240 kg hm(-2) nitrogen application rate with conventional urea) were recommended for nitrogen fertilizer application in the study area.
摘要：
With ongoing climate change, aridity is increasing worldwide, affecting biodiversity and ecosystem function in drylands. However, how the depth-profile microbial community structure and metabolic limitations change along aridity gradients are still poorly explored. Here, 16S rRNA and ITS amplicon sequencing and ecoenzymatic stoichiometry analysis were used to investigate both bacterial and fungal diversities and resource limitations in 1 m depth profiles across a wide aridity gradient (0.51-0.78) in a semiarid region. Results showed a sharp decrease in microbial diversity with soil depth, accompanied by an increase in microbial phosphorus (P) vs. N (nitrogen) limitation and a decrease in microbial carbon (C) vs. nutrient limitation. Aridity led to a strong shift in microbial community composition, but aridity has a threshold effect on microbial resource limitation through impacts on soil pH and C/P or N/P. When the aridity threshold (1-precipitation/evapotranspiration) exceeds 0.65, relationship between aridity and microbial resource demand was decoupled; but at aridity threshold = 0.65, microbial relative C limitation and C-acquiring enzyme activity dropped. These results suggest that aridity might have a stronger influence on microbial community composition, than on diversity, shaped by inherent soil biotic factors (i.e., MBC:MBP or MBN:MBP). These findings suggest that soil microbial diversity or enzymatic stoichiometry may be not necessary to mirror changes in water availability in the drylands, while aridity would be well explained by microbial community composition.
