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Spatiotemporal characteristics and driving factors of groundwater drought in Nile River Basin (NRB)

CATENA 2025年 257卷

作者： Mesfin Mamo Haile Fadong Li Zhipin Ai Gang Chen Peifang Leng Shandong Yucheng Agro-ecosystem National Observation and Research Station Yucheng Comprehensive Experiment Station Institute of Geographic Sciences and Natural Resources Research Chinese Academy of Sciences Beijing 100101 China Key Laboratory of Ecosystem Network Observation and Modeling Institute of Geographic Sciences and Natural Resources Research Chinese Academy of Sciences Beijing 100101 China College of Resources and Environment University of Chinese Academy of Sciences Beijing 100101 China Department of Hydraulic and Water Resources Engineering Ambo University Ambo Ethiopia Department of Civil & Environmental Engineering College of Engineering Florida A&M University-Florida State University Tallahassee USA

Understanding groundwater drought characteristics and the driving factors is vital for sustainable groundwater management. Using Nile River Basin (NRB) as a testbed, this research examines spatial patterns, temporal changes, and overall trends of groundwater droughts using standardized groundwater drought index (SGDI) model in areas with distinct climate conditions. The study quantitatively assesses the influence of anthropogenic (LULC), meteorological, and teleconnection factors using correlation analysis, cross-wavelet transform, and Random Forest (RF) methods. Based on this study, groundwater droughts predominantly occurred between 2003 and 2013 with a general decreasing trend, and the occurrence of groundwater droughts was closely aligned with meteorological drought, with a propagation time of at least three months. Precipitation positively contributed to mitigating groundwater droughts across the study area but was insufficient to reverse drought intensification. Teleconnection factors significantly influenced the development of groundwater droughts, with DMI and ENSO identified as key contributors. Changes in LULC, such as a decrease in barren land, cropland, and grassland, along with an increase in vegetation and water bodies, played a key role in alleviating groundwater droughts in NRB. Conversely, the expansion of urban areas did not seem to worsen drought conditions. Quantitative analysis highlights LULC and meteorological factors as the primary drivers of groundwater droughts, though the influence of teleconnection factors, while weaker, remains important. Overall, this study highlights factors influencing groundwater droughts, supporting decision-making for sustainable groundwater management in diverse climates.

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Sucrose metabolism and hormone interaction determine the fate of different florets within central spikelet of wheat

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Journal of Integrative Agriculture 2025年

作者： Wan Sun Jie Ren Xuechen Xiao Wanqing Zhang Haoran Li Zhimin Wang Zhigan Zhao Zhencai Sun Xubo Zhang Yinghua Zhang College of Agronomy and Biotechnology China Agricultural University Beijing 100193 China Department of Agricultural and Forest Sciences and Engineering University of Lleida–AGROTECNIO-CERCA Center Lleida 25198 Spain Key Laboratory of Ecosystem Network Observation and Modeling Institute of Geographic Sciences and Natural Resources Research Chinese Academy of Sciences Beijing 100101 China Engineering Technology Research Center for Agriculture in Low Plain Areas Hebei 061800 China

In the central spikelet, floret primordia proximal to rachis typically develop into fertile florets, while those distal ones tend to abort. However, the mechanism driving these divergent outcomes remain unclear. To elucidate this mechanism, a two-year field experiment was conducted, analyzing the differences between fertile (floret 1) and abortive florets (floret 5) at phenotypic, physiological, cellular, and transcriptional levels. Our results showed that floret 1 (F1) developed earlier than floret 5 (F5), evidenced as distinct floret and anther cell morphology. This developmental difference was associated with distinct metabolic strategies: F1 prioritizes starch biosynthesis by enhancing photosynthetic efficiency and reducing thermal dissipation, while F5 diverts carbon to trehalose metabolism under resource constraints. Transcriptomic profiling revealed 17,711 differentially expressed genes, predominantly enriched in carbohydrate metabolism. key starch-related genes ( WAXY , SS , GBE1 ) were upregulated in F1, while trehalose synthesis genes ( TPS.5 , TPS.6 , TPP.7 ) dominated in F5, reflecting a metabolic trade-off between growth and survival. Hormonal profiling revealed elevated indole-3-acetic acid (IAA) levels in F1, driven by upregulated genes encoding enzymes of TDC and YUCCA, whereas abscisic acid (ABA) level increased in F5, mediated by NCED. Specially, tissue-specific regulation in fertile floret was clarified: lemma tissues enriched in photosynthesis genes supplied localized carbon, anthers relied on sucrose cleavage genes to sustain pollen development, and ovary activated lipid biosynthesis genes for embryogenesis. Collectively, we propose a model where IAA-starch synergy in proximal florets establishes a competitive metabolic sink, whereas ABA-T6P interplay in distal florets enforces developmental arrest, thereby optimizing resource allocation and reproductive success. The proposed regulatory framework provides novel views for improving floret fertili

关键词： fertile floret abortive floret sucrose metabolism hormone

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Impact of environmental factors on water quality at multiple spatial scales and its spatial variation in Huai River Basin, China

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Science China Earth Sciences 2018年第1期61卷 82-92页

作者： XIA Jun WANG LongFeng YU JingJie ZHAN CheSheng ZHANG YongYong QIAO YunFeng WANG YueLing Key Laboratory of Water Cycle & Related Land Surface Processes Institute of Geographic Sciences and Natural Resources Research Chinese Academy of Sciences Beijing 100101 China University of Chinese Academy of Sciences Belting 100049 China State Key Laboratory of Water Resources & Hydropower Engineering Science Wuhan University Wuhan 430072 China Key Laboratory of Ecosystem Network Observation and Modeling Institute of Geographic Sciences and Natural Resources Research Chinese Academy of Sciences Beijing 100101 China

Quantitative assessment of water quality and its spatial variation identification, as well as the discernment of primary factors affecting water quality are in its urgent in water environment management. In this study, four key water quality indicators,namely, ammonia nitrogen(NH_4^+-N), permanganate index(COD_(Mn)), total phosphorus(TP) and total nitrogen(TN) at 71 sampling sites were selected to evaluate water quality and its spatial variation identification. More concerns were emphasized on the anthropogenic factors(land use pattern) and natural factors(river density, elevation and precipitation) to quantify the overall water quality variations at different spatial scales. Results showed that the Yi-Shu-Si River sub-basin had a better water quality status than the Huai River sub-basin. The moderate polluted area nearly distributed in the upper and middle reaches of the Shaying River and Guo River. The high cluster centers which were surrounded with COD_(Mn), NH_4^+-N, TN and TP mainly also distributed in the upper and middle reaches of the Shaying River and Guo River. Redundancy analysis showed that the 200 m buffer area acted as the most sensitive area, which was easily subjected to pollution. The precipitation was identified as the most important variables among all the studied hydrological units, followed by farmland, urban land or elevation. The point source pollution was still existed although the non-point source pollution was also identified. The urban surface runoff pollution was severer than farmland fertilizer loss at the sub-basin scale in flood season, while the farmland showed "small-scale" effects for explaining overall water quality variations. This research is helpful for identifying the overall water quality variations from the scale-process interactions and providing a scientific basis for pollution control and decision making for the Huai River Basin.

关键词： Fuzzy comprehensive assessment Environmental factors Moran＇s I Redundancy analysis Pearson＇s correlation analysis Huai River Basin

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Uncertainties in above ground tree biomass estimation

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Journal of Forestry Research 2021年第5期32卷 1989-2000页

作者： Lihou Qin Shengwang Meng Guang Zhou Qijing Liu Zhenzhao Xu College of Forestry Beijing Forestry UniversityBeijing 100083People’s Republic of China Qianyanzhou Ecological Research Station Key Laboratory of Ecosystem Network Observation and ModelingInstitute of Geographic Sciences and Natural Resources ResearchChinese Academy of SciencesBeijing 100101People’s Republic of China Jiangxi Academy of Forestry Nanchang 330022People’s Republic of China

Models of above-ground tree biomass have been widely used to estimate forest biomass using national forest inventory ***,many sources of uncertainty affect above-ground biomass estimation and are challenging to *** this study,the uncertainties associated with the measurement error in independent variables(diameter at breast height,tree height),residual variability,variances of the parameter estimates,and the sampling variability of national inventory data are estimated for five above-ground biomass *** results show sampling variability is the most significant source of *** measurement error and residual variability have negligible effects on forests above-ground biomass ***,a reduction in the uncertainty of the sampling variability has the greatest potential to decrease the overall *** power model containing only the diameter at breast height has the smallest *** findings of this study provide suggestions to achieve a trade-off between accuracy and cost for above-ground biomass estimation using field work.

关键词： Above-ground biomass Measurement error Residual variability Parameter estimates Sampling variability

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Understanding sustainability of soil and water resources in a critical zone perspective

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Science China Earth Sciences 2019年第11期62卷 1716-1718页

作者： Ganlin ZHANG Yongguan ZHU Ming'an SHAO State Key Laboratory of Soil and Sustainable Agriculture Institute of Soil ScienceChinese Academy of SciencesNanjing 210008China Key Laboratory of Urban Environment and Health Institute of Urban EnvironmentChinese Academy of SciencesXiamen 361021China Key Laboratory of Ecosystem Network Observation and Modeling Institute of Geographic Sciences and Natural Resources ResearchChinese Academy of SciencesBeijing 100101China University of Chinese Academy of Sciences Beijing 100049China

Soil and water resources are fundamental for human *** the status and the evolution of regional water and soil resources is the prerequisite for their sustainable *** is severely constrained by water and soil resources which are subject to soil forming processes under different natural factors such as climate and relief,and also influenced by diversified landuse histories and *** and security of water and soil resources are therefore influenced by both natural and anthropogenic processes.

关键词： soil management resources

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Different responses of agroecosystem greenhouse gas emissions to tillage practices in a Chinese wheat–maize cropping system

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Carbon Research 2023年第1期2卷 1-14页

作者： Li, Zhaoxin Zhang, Qiuying Li, Zhao Qiao, Yunfeng Du, Kun Yue, Zewei Tian, Chao Leng, Peifang Cheng, Hefa Chen, Gang Li, Fadong Key Laboratory of Ecosystem Network Observation and Modeling Shandong Yucheng Agro-ecosystem National Observation and Research Station Institute of Geographic Sciences and Natural Resources Research CAS Beijing100101 China College of Resources and Environment UCAS Beijing100049 China Chinese Research Academy of Environmental Sciences Beijing100012 China Peking University Beijing100091 China Department of Civil & Environmental Engineering College of Engineering Florida A&M University-Florida State University Tallahassee32306 United States

To mitigate greenhouse gas (GHG) emissions of intensified agriculture, conservation practices are gradually being implemented in Chinese wheat–maize cropping systems. However, the effects of different tillage practices on agricultural field GHG emissions and subsequent global warming potential (GWP) are poorly documented. In this study, a three-year field experiment was conducted from 2019 to 2021 to assess the effects of tillage on the emissions of carbon dioxide (CO2), methane (CH4), nitrous oxide (N2O), and eventually GWP. Compared to conventional tillage (CT), no-tillage (NT) significantly decreased CO2, CH4, and N2O emissions by 35.43%, 67.33%, 339.07%, respectively, which resulted in a decrease of 37.25% in GWP during three annual cycles. Based on the results of this study, soil could potentially act as a net source of CO2 and CH4 under both CT and NT, and a net sink of N2O under NT. Annually, non-growing season contributed 16.9%, 15.6%, and 13.8% soil CO2, CH4, and N2O fluxes, and 16.6% GWP under CT and 17.3%, 16.4%, 21.6%, and 17.3% under NT, respectively. Compared to CT, NT improved the aboveground biomass and grain yields of wheat by 21.3% and 13.3% from averaged results, respectively;no significant differences were found for maize yields. Although principal component analysis showed that soil temperature had higher correlations with CO2 emissions and GWP as compared to soil moisture, soil moisture affected GHG emissions more than soil temperature as demonstrated by the structural equation model. The modeling analysis found that NT increased soil moisture, pH, and bulk density, thus increasing soil organic carbon and decreasing total nitrogen content, eventually inhibiting GHG emissions. This research demonstrated that NT had the potential to mitigate GHG emissions, yet stability needed further investigation on long-term scales.∙ Graphical Abstract: [Figure not available: see fulltext.] © 2023, The Author(s).

关键词： Greenhouse gas emissions

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Estimation of diffuse photosynthetically active radiation and the spatiotemporal variation analysis in China from 1981 to 2010

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Journal of Geographical Sciences 2014年第4期24卷 579-592页

作者： REN Xiaoli HE Honglin ZHANG Li YU Guirui Key Laboratory of Ecosystem Network Observation and Modeling Institute of Geographic Sciences and Natural Resources Research CAS Beijing 100101 China University of Chinese Academy of Sciences Beijing 100049 China

Photosynthetically active radiation （PAR） is the energy source of plant photosyn thesis, and the diffuse component can enhance canopy light use efficiency, thereby increasing the carbon uptake. Therefore, diffuse PAR is an important driving factor of ecosystem productivity models. In this study, we estimated the diffuse PAR of over 700 meteorological sites in China from 1981 to 2010 using an empirical model based on observational data from Chinese ecosystem Research network （CERN） and China Meteorology Administration. Then we derived the spatial data set of 10 km monthly diffuse PAR using ANUSPLIN software, and analyzed the spatiotemporal variation characteristics of diffuse PAR through GIS and trend analysis techniques. The results showed that：（1） The spatial patterns of annual average diffuse PAR during 1981-2010 are heterogeneous across China, lower in the northeast and higher in the west and south. The nationwide average value for 30 years ranges from 6.66 mol m-2 d-1 to 15.27 mol m-2 d-1, and the value in summer is the biggest while the value in winter is the smallest. （2） There is an evident increasing trend of annual diffuse PAR during recent 30 years, with the increasing amplitude at 0.03 mol m-2 d-l/10a. But a significant declining trend is shown in the first 10 years, and obvious anomalies can be seen in 1982, 1983, 1991 and 1992. And there is a downtrend in spring and an uptrend in all the other seasons. （3） The spatial distribution of temporal variation rates of diffuse PAR is inhomogeneous across the country, generally decreasing in the north and increasing in the south.

关键词： photosynthetically active radiation （PAR） diffuse fraction diffuse PAR spatiotemporal variations

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Surface water quality forecasting based on ANN and GIS for the Chanzhi Reservoir, China

Surface water quality forecasting based on ANN and GIS for t...

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2nd International Conference on Information Science and Engineering, ICISE2010

作者： Song, Shuai Zheng, Xilai Li, Fadong Natural Resources Research Key Laboratory of Ecosystem Network Observation and Modeling Institute of Geographic Sciences Beijing 100101 China Key Lab. of Marine Environment and Ecology Ministry of Education Ocean University of China Qingdao China Graduate University of Chinese Academy of Science Beijing China

ISBN: (纸本)9781424480968

Artificial neural network (ANN) based on Arc Engine (AE) of GIS is used to predict surface water quality in the Chanzhi Reservoir, Qingdao, China. The results can reflect the water quality change trends with less than 10% average relative error. Using MS SQL Server database technology combined with Geodatabase, the system achieves the fundamental geographic information and hydrological data management, and water quality prediction. It uses GIS component technology to build an efficient and stable platform which can apply to general surface water quality prediction. This software has good information extraction and query functions to help decision-makers to manage water resource better. © 2010 IEEE.

关键词： Reservoirs (water)

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Climate change induced range shifts of Galliformes in China

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Integrative Zoology 2010年第2期5卷 154-163页

作者： Renqiang LI Huidong TIAN Xinhai LI Key Laboratory of Ecosystem Network Observation and Modeling Institute of Geographic Sciences and Natural Resources ResearchChinese Academy of SciencesBeijingChina State Key Laboratory of Integrated Pest Management on Pest Insects and Rodents Institute of ZoologyChinese Academy of SciencesBeijingChina Key Laboratory of the Zoological Systematics and Evolution Institute of ZoologyChinese Academy of SciencesBeijingChina Graduate University of Chinese Academy of Sciences BeijingChina

Climate change will cause range shifts of many species in the *** might be particularly vulnerable to climate change,as they have low dispersal *** is known about their possible responses to the future *** used a generalized additive model to predict the current and future ranges of all 63 Galliformes in China,based on a comprehensive species occurrence database and a combination of climate *** environmental variables(*** and human footprint index)were also considered,as well as the latitude and longitude of the *** component analysis was conducted to illustrate the association between environmental variables and Galliformes *** the Special Report on Emissions Scenarios(SRES)A2 climate change scenario for 2071–2100,we projected that 29 species would have range shifts over 50%,including 13 endemic *** at higher elevation face greater range *** shifts are greater than those in other *** suggest conservationists pay special attention to the 29 Galliformes that face extensive range shifts,especially the endemic species among them.

关键词： climate change Galliformes generalized additive model principal component analysis range shift

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Selective harvesting at rational intervals promotes carbon sequestration in temperate coniferous and broad-leaved mixed forests in China

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Journal of Forestry Research 2021年第3期32卷 1025-1033页

作者： Jihua Hou Junxia Tian Li Xu Zihao Zhang Zhi Chen Nianpeng He Beijing Key Laboratory of Forest Resources and Ecosystem Processes Beijing Forestry UniversityBeijing 100083People’s Republic of China Key Laboratory of Ecosystem Network Observation and Modeling Institute of Geographic Sciences and Natural Resources ResearchChinese Academy of SciencesBeijing 100101People’s Republic of China College of Resources and Environment University of Chinese Academy of SciencesBeijing 100049People’s Republic of China Key Laboratory of Vegetation Ecology Ministry of EducationNortheast Normal UniversityChangchun 130024People’s Republic of China

Evidence-based selective cutting at prescribed intervals as part of good forest management can enhance the carbon sequestration capacity of the *** effect of forest management on carbon sequestration has,however,not been ***,carbon content of various organs was measured for 323 tree species,247 shrub species,and233 herb species in seven temperate coniferous and broadleaved mixed forests that were subjected to selective cutting with restoration durations of 100,55,45,36,25,14,and6 years to explore dynamic changes in carbon *** results showed that biomass carbon allocation in different organs followed a pattern:trunk>root>branch>leaf for all *** longer restoration durations,more carbon accumulated in different organs and in ***,when the restoration duration exceeded 50 years,carbon storage in ecosystem was larger than that in primary forests with 100-year cutting intervals,suggesting that a reasonable selective cutting interval can increase forest carbon *** diameter at breast height(DBH)and forest carbon storage were significantly positively correlated,and carbon storage of selectively cut forests exceeded that of primary forests when the stand mean DBH exceeded 15.66 ***,mean DBH of forests can be an indicator for combining sustainable forest management and forest carbon ***,the classic coefficients of 0.45 and 0.50 used to estimate carbon sequestration underestimated values by 2.65%and overestimated by 8.16%,respectively,in comparison with the measured carbon content from different plant organs.

关键词： Selective cutting Forests Diameter at breast height Carbon Storage Management Restoration

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