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Journal of Plant Ecology 2023年第2期16卷 1-12页

作者： Xu-Yan Liu Yu-Kun Hu Beijing Key Laboratory of Wetland Services and Restoration Institute of Wetland ResearchChinese Academy of ForestryBeijing 100091China Key Laboratory of Ecosystem Network Observation and Modeling Institute of Geographic Sciences and Natural Resources ResearchChinese Academy of SciencesBeijing 100101China

多种化学元素对于植物生长和生存、群落结构及植被功能具有至关重要的作用。化学多样性,即群落中植物元素含量的变异大小,能为深入探究植物养分策略和群落构建机制提供重要见解。然而,目前对于氮和磷以外的其它元素的化学多样性认识很少... 详细信息

多种化学元素对于植物生长和生存、群落结构及植被功能具有至关重要的作用。化学多样性,即群落中植物元素含量的变异大小,能为深入探究植物养分策略和群落构建机制提供重要见解。然而,目前对于氮和磷以外的其它元素的化学多样性认识很少,而且主要集中于植物地上部分。本研究通过对沿局域土壤化学梯度下的森林沼泽林下植物群落的调查,测定优势和亚优势植物叶片和细根11种元素含量,使用n维的超体积指数,探究了叶片和细根化学多样性的变化,及其与土壤因子间的关系。研究发现植物化学多样性随着土壤铝、锰、镁和锌含量的增加而减少,而与土壤氮、磷、钾、钠和铁含量及土壤pH和碳氮比之间没有关系。在控制物种多样性和土壤水分含量的影响后,这些变化格局仍然稳固。此外,叶和根化学多样性之间存在显著正相关,两者与土壤因子的关系相似。植物根化学多样性略高于叶化学多样性,但差异不显著。这些研究结果强调了局域尺度下土壤微量元素在决定植物化学多样性中的重要作用。植物叶和根化学多样性具相似的大小和格局,表明了在局域尺度下相似的环境因子驱动了植物地上与地下化学多样性。本研究结果对进一步认识土壤养分影响下的植物群落构建和生态系统功能具有重要的意义。

关键词：地上与地下联系环境梯度细根功能多样性超体积多元素微量元素

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Exploring the effects of crop growth differences on radar vegetation index response and crop height estimation using dynamic monitoring model

Exploring the effects of crop growth differences on radar ve...

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2024 ISPRS Technical Commission I Mid-term Symposium on Intelligent Sensing and Remote Sensing Application

作者： Wang, Bo Liu, Yu Sheng, Qinghong Li, Jun Wang, Shuwei Qiao, Yunfeng He, Honglin College of Astronautics Nanjing University of Aeronautics and Astronautics Nanjing China Changshu National Agro-Ecosystem Observation and Research Station Institute of Soil Science Chinese Academy of Sciences Nanjing China Institute of Geographic Sciences and Resources Chinese Academy of Sciences Beijing China Key Laboratory of Ecosystem Network Observation and Modeling Institute of Geographic Sciences and Natural Resources Research Chinese Academy of Sciences Beijing China

Synthetic aperture radar (SAR) has emerged as a promising technology for monitoring crop plant height due to its ability to capture the geometric properties of crops. Radar vegetation index (RVI) has been extensively utilized for qualitative and quantitative remote sensing monitoring of vegetation growth dynamics. However, the combination of crop, growing environment, and temporal dynamics makes crop monitoring data a complex task. Despite the relatively simple underlying mechanisms of this phenomenon, there is still a need for more research to identify specific vegetation structures that correspond to changes in the response of vegetation indices. Building upon this premise, this study utilized a dynamic monitoring model to conduct dynamic monitoring of plant height for three common crops: rice, wheat, and maize. The findings revealed that (1) models developed for specific spatial and temporal scales of particular crop varieties may not accurately predict crop growth in different regions or with different varieties in a timely manner, due to growth variations;(2) these models maintain accuracy over a range of plant heights, such as rice at around 70cm, wheat at around 50cm, and maize at around 150cm;(3) among the three crops, planting density was identified as the main factor influencing the differences in RVI response. This research contributes to our comprehension of the dynamic response of RVI to different growth conditions in crops, and offers valuable insights and references for agricultural monitoring. © 2024 Bo Wang et al.

关键词： Crops

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Water sources for typical desert vegetation in the Ebinur Lake basin

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Journal of Geographical Sciences 2022年第6期32卷 1103-1118页

作者： HAO Shuai LI Fadong College of Geographic Science and Tourism Xinjiang Normal UniversityUrumqi 830054China Key Laboratory of Xinjiang Uygur Autonomous Region Xinjiang Laboratory of Lake Environment and Resources in Arid AreaUrumqi 830054China Key Laboratory of Ecosystem Network Observation and Modeling Institute of Geographic Sciences and Natural Resources ResearchCASBeijing 100101China College of Resource and Environment University of Chinese Academy of SciencesBeijing 100190China

In arid and semi-arid environments,desert vegetation plays an important role in preventing soil erosion by wind and helps maintain the stability of desert and oasis *** types of typical desert vegetation,namely Populus euphratica,Haloxylon ammodendron,Nitraria sibirica,and Halostachs caspica,corresponding to different habitats(i.e.,river bank,sand dune,desert,and salt marsh)were chosen as the model vegetation in this ***δ^(2)H andδ^(18)O for rainwater,soil water,and plant water were applied to identify the water sources and quantify the proportions of different water sources used over the entire plant growth period(from March to October).The results showed that the precipitationδ^(2)H andδ^(18)O in the Ebinur Lake basin varied from-142.5‰to-0.6‰and from-20.16‰to 1.20‰,*** largestδ^(2)H andδ^(18)O values occurred in summer and the smallest in *** soil waterδ^(2)H andδ^(18)O of the four habitats decreased gradually with increasing ***δ^(2)H andδ^(18)O values of water extracted from the stems of the four plants had similar variation trends,that is,the maximum was observed in spring and the minimum in *** the four plants,*** had the highest stable isotopic values in the stem water,followed by ***,***,and *** water sources and utilization ratios of desert vegetation varied across different growth *** the growing period,*** mainly used groundwater,whereas the water source proportions used by *** varied greatly throughout the growing *** spring,plants mainly relied on surface soil water,with a contribution rate of 80%-94%.However,in summer,the proportion of deep soil water used was 31%-36%;and in autumn,the proportion of middle soil water used was 33%-36%.*** mainly relied on topsoil water in spring and autumn,and the proportion of soil water in the middle layer slightly increased to 20%-36%in *** mainly used intermediate so

关键词： desert vegetation water use stable isotopes of hydrogen and oxygen Ebinur Lake basin

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Impact of precipitation change in the Yangtze River source area on groundwater from the perspective of ground-based and satellite-based observations

Transactions in Earth, Environment, and Sustainability

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Transactions in Earth, Environment, and Sustainability 2024年第1期2卷 3 - 23页

作者： Guangyao Shi Erfu Dai Lhasa Plateau Ecosystem Research Station Key Laboratory of Ecosystem Network Observation and Modeling Institute of Geographic Sciences and Natural Resources Research Chinese Academy of Sciences ChinaUniversity of Chinese Academy of Sciences China

In the context of global climate change, the hydrological cycle of the Yangtze River source area has produced significant changes. It is of great practical value to study the influence of regional precipitation changes and precipitation events on regional water resources, especially groundwater. This study uses base flow segmentation and GRACE groundwater reserve calculation technology to examine precipitation’s spatial and temporal variation, especially extreme precipitation events, in the Yangtze River source area. The events analyzed were the extreme precipitation-runoff-base flow response from the Yangtze River source, the extreme precipitation-terrestrial water (surface water and groundwater) response, and the comparison of these events. The findings indicated that extremely strong precipitation, maximum precipitation for five consecutive days, days of moderate rain and above moderate rain intensity precipitation, the longest number of precipitation days, and other extreme precipitation indices had a significantly increasing trend and increased intensity of extreme precipitation events, the regional differences in precipitation trended less significantly. The base flow index gradually increased at a rate of 0.0014 yr-1, suggesting the overall increase of water resources and the contribution rate of groundwater to the runoff was an increased trend . There is a high correlation between the change of water resources in the source area and the change of precipitation, and the increased precipitation influenced an increase in groundwater and regional water resources. These findings inform current knowledge of precipitation-groundwater response mechanisms in alpine and arid regions such as the Qinghai-Tibet Plateau.

关键词： Yangtze River source precipitation extreme precipitation water resources groundwater

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Seed nutrient is more stable than leaf in response to changing multiple resources in an alpine meadow

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Ecological Processes 2023年第1期12卷 589-597页

作者： Jiapu Li Dashuan Tian Kailiang Yu Hongbo Guo Ruiyang Zhang Jinsong Wang Qingping Zhou Shuli Niu Key Laboratory of Ecosystem Network Observation and Modeling Institute of Geographic Sciences and Natural Resources ResearchChinese Academy of SciencesBeijing 100101China College of Resources and Environmental Sciences Nanjing Agricultural UniversityNanjing 210095China College of Resources and Environment University of Chinese Academy of SciencesBeijing 100101China Institute of Qinghai-Tibetan Plateau Southwest Minzu UniversityChengdu 610041China High Meadows Environmental Institute Princeton UniversityPrinceton 02138USA

Background It has been long thought that nitrogen(N),phosphorus(P)concentrations and their ratios(N:P)in metabolically active or functional organs(i.e.,leaves)are less responsive to environmental *** attention,however,has been paid to the reproductive organs-seeds,while seeds may maintain their nutrients more stable for the evolutionary fitness of next *** Here,we conducted a field experiment of N,P addition and drought in an alpine meadow,aiming to compare the difference of leaf and seed nutrients and stoichiometric ratios in response to these resource treatments and their *** dominant species were selected among grass and forb functional groups,including Elymus nutans,Deschampsia caespitosa,Artemisia roxburghiana and Polygonum *** Under natural conditions,leaf N and P concentrations were consistently lower than seed among ***,leaf nutrients were much more sensitive than seed nutrients to N and P ***,N or P addition accordingly increased leaf N or P concentration by 22.20-44.24%and 85.54-93.61%,while only enhanced seed N or P concentration by 5.15-17.20%and 15.17-32.72%,*** N or P concentration was significantly reduced by P or N addition,but seed nutrients remained *** contrast,drought did not change both organ ***,nutrient addition and drought had synergistic interactions on leaf nutrients,but not on seed *** This study highlights that seed nutrient concentrations could be more stable than metabolically active leaf organ when facing multidimensional resource *** complements the traditional view on the‘Stable Leaf Nutrient Hypothesis’with the involvement of reproductive *** less responsiveness of seed nutrients suggests the adaptive strategy to ensure the success of next generations and long-term plant demographic stability.

关键词： Alpine meadow Leaf Multiple resource change Nitrogen concentration N:P ratio Phosphorus concentrations Seed

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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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Divergent effects of climate change on cropland ecosystem water use efficiency at different elevations in southwestern China

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Journal of Geographical Sciences 2022年第8期32卷 1601-1614页

作者： TAO Jian ZHU Juntao ZHANG Yangjian DONG Jinwei ZHANG Xianzhou School of Public Administratio n Shand ong Tech no logy and Business UniversityYantai 264005ShandongChina Nagqu Alpine Grassland Research Station Key Laboratory of Ecosystem Network Observation and ModelingInstitute of Geographic Sciences and Natural Resources ResearchCASBeijing 100101China Key Laboratory of Land Surface Pattern and Simulation Institute of Geographic Sciences and Natural Resources ResearchCASBeijing 100101China

Understanding climatic effects on cropland water use efficiency at different elevations is imperative for managing agricultural water and production in response to ongoing climate change in climate-sensitive areas with complex topography, such as southwestern China. We investigated climatic effects on cropland water use efficiency in southwestern China at each 100-m elevation bin during 2001–2017. The maximum water use efficiency was 1.71 gC kg^(–1) H_2O for the 1900–1999 m elevation bin under the growing season temperature and precipitation of 14.58±0.32℃ and 965.40±136.45 mm, respectively. The water use efficiency slopes were dominated by the evapotranspiration slopes at elevations below 1999 m but were controlled by the gross primary productivity slopes at elevations above 2000 m. This difference was caused by the substantial responses of evaporation to climate change at lower elevations and the increased climatic sensitivity of gross primary productivity at higher elevations. In comparison to those at other elevations, croplands at lower elevations were more vulnerable to extreme drought because of the dominant role fluctuating evapotranspiration played in water use efficiency. The findings will improve cropland water management in the study area.

关键词： cropland water use efficiency southwestern China elevational gradient

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Climate change reductions in lake ice cover duration and thickness help regulate the carbon sink potential of plateau type lakes

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National Science Open 2024年第5期3卷 114-129页

作者： Di Shen Yafeng Wang Junjie Jia Shuoyue Wang Kun Sun Yang Gao College of Earth and Environment Science Lanzhou UniversityLanzhou 730000China State Key Laboratory of Tibetan Plateau Earth System Environment and Resources(TPESER)Institute of Tibetan Plateau ResearchChinese Academy of SciencesBeijing 100101China Key Laboratory of Ecosystem Network Observation and Modeling Institute of Geographic Sciences and Natural Resources ResearchChinese Academy of SciencesBeijing 100101China College of Resources and Environment University of Chinese Academy of SciencesBeijing 100049China

Lake ice changes in winter under the influence of global climate change,but how lake ice changes will regulate water gross primary productivity(GPP)and carbon sequestration capacity is still ***,we evaluated and analyzed the geographic spatial pattern and dynamic changes of lake ice and GPP on the Qinghai-Tibetan Plateau(QTP)in the past 20 *** show that lake ice duration on the QTP is 123.36±2.43 d on average,although longer for lakes at higher altitudes,of moderate size,and with shallower *** ice thickness is between 55-66 cm on average,and its GPP on the QTP is between 0.17-3.35 g C m^(-2)d^(-1).In the context of global climate change,reductions in lake ice cover duration and changes in ice thickness on the QTP increased phytoplankton GPP during the winter freeze period while decreasing Carbon dioxide(CO_(2))emissions during the melting period.

关键词： Qinghai-Tibetan Plateau lake ice gross primary productivity carbon sequestration

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Contribution of irrigation to the production of maize, wheat, and rice in the major global producing countries

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National Science Review 2024年第11期11卷 44-46页

作者： Zhipin Ai Julien Boulange Xin Zhao Fadong Li Rashid Mahmood Kiril Manevski Yonghui Yang Guirui Yu Key Laboratory of Ecosystem Network Observation and Modeling Institute of Geographic Sciences and Natural Resources ResearchChinese Academy of Sciences College of Resources and Environment University of Chinese Academy of Sciences United Graduate School of Agricultural Science Tokyo University of Agriculture and Technology Earth System Division National Institute for Environmental Studies Water Engineering and Management Asian Institute of Technology Sino-Danish College University of the Chinese Academy of Sciences Department of Agroecology Aarhus University Center for Agricultural Resources Research Institute of Genetics and Developmental Biology Chinese Academy of Sciences

Global megatrends in population growth and climate change, together with regional conflicts, are driving an increasing and unequal demand for food and consequently pose a serious threat to food security worldwide. Studies have shown that increasing cropland productivity, rather than expanding cropland area, may be a more viable strategy to promote food security [1]. From an agronomic perspective, irrigation can greatly enhance crop yield and productivity,

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From tree to forest:Multiple carbon sink constraints

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The Innovation 2023年第4期4卷 19-20页

作者： Hui Liu Lin Zhang Qin Ma Wei Zhao Yiping Chen Guangdong Provincial Key Laboratory of Applied Botany Key Laboratory of Vegetation Restoration and Management of Degraded EcosystemsSouth China Botanical GardenChinese Academy of SciencesGuangzhou 510650China South China National Botanical Garden Guangzhou 510650China State Key Laboratory of Tibetan Plateau Earth System Environmentand Resources(TPESER)Institute of Tibetan Plateau ResearchChinese Academy of SciencesBeijing 100101China School of Geography Nanjing Normal UniversityNanjing 210023China Key Laboratory of Ecosystem Network Observation and Modeling Institute of Geographic Sciences and Natural Resources ResearchChinese Academy of SciencesBeijing 100101China School of Geospatial Engineering and Science Sun Yat-Sen UniversityZhuhai 519082China

Forests are the largest carbon sinks among terrestrial *** sequestrate carbon primarily through tree growth but are currently under severe threat from global ***,Tavares et al.1 identified a crucial trait,the xylem hydraulic safety margin(HSM),for predicting the risk of drought-induced tree mortality and biomass in Amazon *** also found that old-growth forests with wide HSMs build more biomass,while fast-growing forests are exposed to greater hydraulic risks and have a higher mortality rate.

关键词： forest tree carbon

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