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Early- And in-season crop type mapping without current-year ground truth: generating labels from historical information via a topology-based approach

arXiv

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arXiv 2021年

作者： Lin, Chenxi Zhong, Liheng Song, Xiao-Peng Dong, Jinwei Lobell, David B. Jin, Zhenong Department of Bioproducts and Biosystems Engineering University of Minnesota Twin Cities St PaulMN United States Ant Group Beijing China Department of Geosciences Texas Tech University LubbockTX United States Key Laboratory of Land Surface Pattern and Simulation Institute of Geographic Sciences and Natural Resources Research Chinese Academy of Sciences Beijing China Department of Earth System Science Center on Food Security and the Environment Stanford University StanfordCA United States

land cover classification in remote sensing is often faced with the challenge of limited ground truth labels. Incorporating historical ground information has the potential to significantly lower the expensive cost associated with collecting ground truth and, more importantly, enable early- and in-season mapping that is helpful to many pre-harvest decisions. In this study, we propose a new approach that can effectively transfer knowledge about the topology (i.e. relative position) of different crop types in the spectral feature space (e.g. the histogram of SWIR1 vs RDEG1 bands) to generate labels, thereby support crop classification in a different year. Importantly, our approach does not attempt to transfer classification decision boundaries that are susceptible to inter-annual variations of weather and management, but relies on the more robust and shift-invariant topology information. We tested this approach for mapping corn/soybeans in the US Midwest and paddy rice/corn/soybeans in Northeast China using landsat-8 and Sentinel-2 data. Results show that our approach automatically generates high-quality labels for crops in the target year immediately after each image becomes available. Based on these generated labels from our approach, the subsequent crop type mapping using a random forest classifier can reach the F1 score as high as 0.887 for corn as early as the silking stage and 0.851 for soybean as early as the flowering stage and the overall accuracy of 0.873 in the test state of Iowa. In Northeast China, F1 scores of paddy rice, corn and soybeans and the overall accuracy can exceed 0.85 two and half months ahead of harvest. Overall, these results highlight unique advantages of our approach in transferring historical knowledge and maximizing the timeliness of crop maps. Our approach supports a general paradigm shift towards learning transferrable and generalizable knowledge to facilitate land cover classification. © 2021, CC BY-NC-ND.

关键词： Remote sensing

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The Belt and Road:Geographical pattern and regional risks

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Journal of Geographical Sciences 2019年第4期29卷 483-495页

作者： WU Shaohong LIU Lulu LIU Yanhua GAO Jiangbo DAI Erfu FENG Aiqing WANG Wentao Institute of Geographic Sciences and Natural Resources Research CASBeijing 100101China Key Laboratory of Land Surface Pattern and Simulation CASBeijing 100101China University of Chinese Academy of Sciences Beijing 100049China National Climate Center China Meteorological AdministrationBeijing 100081China Administrative Center for China Agenda 21 Beijing 100862China

Building the Belt and Road is initiatives of China to promote win-win international cooperation in the new era, aiming at green, health, intellect and peace and the joint development with people of the countries along the route. Systematic analysis on environmental characteristics, evolutionary tendency and future risks are certainly the scientific fundamentals of sustainable development for the Belt and Road construction. Applied remote sensing monitoring, statistical analysis, this paper investigates the regional characteristics of climate, topography, soil, hydrology, vegetation cover and terrestrial ecosystems production, as well as socio-economic conditions. Based on the regional characteristics, the Belt and Road is divided into 9 sub-regions: Central and Eastern Europe sub-region with cold and humid climate, Mongolia and Russia sub-region with cold and arid climate, Central and West Asia arid sub-region, Southeast Asia sub-region with warm and humid climate, Pakistan arid sub-region, Bangladesh-India-Myanmar sub-region with warm and humid climate, Eastern China monsoon sub-region, Northwest China arid sub-region and Tibetan Plateau sub-region. Combining modeling simulation with scenario projections, natural disaster assessment methodology is used to assess the risk of extreme events including heat waves, droughts and floods in the coming 30 years(2021–2050). Results show that, on the basis of the regional framework, the western Eurasia would be a warming trend; both sides of Qinghai-Tibet Plateau in high temperature and heat waves risk; Central and Eastern Europe sub-region with cold and humid climate in high drought risk; Bangladesh-India-Myanmar sub-region with warm and humid climate as well as Eastern China in high risk of flooding.

关键词： the Belt and Road regional characteristics extreme events environmental change risks

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Corrigendum to "Potentially toxic elements exposure biomonitoring in the elderly around the largest polymetallic rare earth ore mining and smelting area in China" [Sci. Total Environ. 853 (2022) 158635]

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The Science of the total environment 2024年 926卷 172174页

作者： Lijun Dai Lingqing Wang Xiaoming Wan Jun Yang Yong Wang Tao Liang Hocheol Song Sabry M Shaheen Vasileios Antoniadis Jörg Rinklebe Key Laboratory of Land Surface Pattern and Simulation Institute of Geographical Sciences and Natural Resources Research Chinese Academy of Sciences Beijing 100101 China. Key Laboratory of Land Surface Pattern and Simulation Institute of Geographical Sciences and Natural Resources Research Chinese Academy of Sciences Beijing 100101 China University of Wuppertal School of Architecture and Civil Engineering Institute of Foundation Engineering Water- and Waste-Management Soil- and Groundwater-Management Pauluskirchstraße 7 42285 Wuppertal Germany. Electronic address: wanglq@***. Department of Environment Department of Environment and Energy Sejong University Seoul 05006 Republic of Korea. University of Wuppertal School of Architecture and Civil Engineering Institute of Foundation Engineering Water- and Waste-Management Soil- and Groundwater-Management Pauluskirchstraße 7 42285 Wuppertal Germany King Abdulaziz University Faculty of Meteorology Environment and Arid Land Agriculture Department of Arid Land Agriculture 21589 Jeddah Saudi Arabia University of Kafrelsheikh Faculty of Agriculture Department of Soil and Water Sciences 33516 Kafr El-Sheikh Egypt. Department of Agriculture Crop Production and Rural Environment University of Thessaly Greece.

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The 2012 Flash Drought Threatened US Midwest Agroecosystems

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Chinese Geographical Science 2019年第5期29卷 768-783页

作者： JIN Cui LUO Xue XIAO Xiangming DONG Jinwei LI Xueming YANG Jun ZHAO Deyu College of Urban and Environment Liaoning Normal UniversityDalian116029China Department of Microbiology and PlantBiology Center for Spatial AnalysisUniversity of OklahomaNormanOK73019USA Ministry of Education Key Laboratory ofBiodiversity Science and Ecological Engineering Institute of Biodiversity ScienceFudan UniversityShanghai200433China KeyLaboratory of Land Surface Pattern and Simulation Institute of Geographic Sciences and Natural Resources ResearchChinese Academyof SciencesBeijing100101China

In the summer of 2012, the US Midwest, the most productive agricultural region in the world, experienced the most intense and widespread drought on record for the past hundred years. The 2012 drought, characterized as ‘flash drought’, developed in May with a rapid intensification afterwards, and peaked in mid-July. ~76% of crop region and 60% of grassland and pasture regions have been under moderate to severe dry conditions. This study used multiple lines of evidences, i.e., in-situ AmeriFlux measurements, spatial satellite observations, and scaled ecosystem modeling, to provide independent and complementary analysis on the impact of 2012 flash drought on the US Midwest vegetation greenness and photosynthesis carbon uptake. Three datasets consistently showed that 1) phenological activities of all biomes advanced 1–2 weeks earlier in 2012 compared to the other years of 2010–2014;2) the drought had a more severe impact on agroecosystems(crop and grassland) than on forests;3) the growth of crop and grassland was suppressed from June with significant reduction of vegetation index, sun-induced fluorescence(SIF) and gross primary production(GPP), and did not recover until the end of growing season. The modeling results showed that regional total GPP in 2012 was the lowest(1.76 Pg C/yr) during 2010–2014, and decreased by 63 Tg C compared with the other-year mean. Agroecosystems, accounting for 84% of regional GPP assimilation, were the most impacted by 2012 drought with total GPP reduction of 9%, 7%, 6%, and 29% for maize, soybean, cropland, and grassland, respectively. The frequency and severity of droughts have been predicted to increase in future. The results imply the importance to investigate the influences of flash droughts on vegetation productivity and terrestrial carbon cycling.

关键词： food security terrestrial carbon cycling eddy covariance Vegetation Photosynthesis Model sun-induced fluorescence(SIF)

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Publisher Correction: Increasing severity of large-scale fires prolongs recovery time of forests globally since 2001

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Nature ecology & evolution 2025年 2025 May 6页

作者： Qiancheng Lv Ziyue Chen Chaoyang Wu Josep Peñuelas Lei Fan Yongxian Su Zeyu Yang Manchun Li Bingbo Gao Jianqiang Hu Chaoqun Zhang Yuheng Fu Qiao Wang State Key Laboratory of Remote Sensing and Digital Earth Faculty of Geographical Science Beijing Normal University Beijing China. State Key Laboratory of Remote Sensing and Digital Earth Faculty of Geographical Science Beijing Normal University Beijing China. zychen@***. The Key Laboratory of Land Surface Pattern and Simulation Institute of Geographical Sciences and Natural Resources Research Chinese Academy of Sciences Beijing China. wucy@***. CSIC Global Ecology Unit CREAF-CSIC-UAB Barcelona Spain. School of Geographical Sciences Southwest University Chongqing China. State Key Laboratory for Ecological Security of Regions and Cities Research Center for Eco-Environmental Sciences Chinese Academy of Sciences Beijing China. School of Geography and Ocean Science Nanjing University Nanjing China. College of Land Science and Technology China Agricultural University Beijing China.

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Rural land use transition of mountainous areas and policy implications for land consolidation in China

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Journal of Geographical Sciences 2019年第10期29卷 1713-1730页

作者： ZHANG Bailin SUN Piling JIANG Guanghui ZHANG Ruijuan GAO Jiangbo School of Economics and Management Tianjin Polytechnic UniversityTianjin 300387 China School of Geography and Tourism Qufu Normal UniversityRizhao 276826 Shandong China State Key Laboratory of Earth Surface Processes and Resource Ecology School of Natural ResourcesFaculty of Geographical Science Beijing Normal UniversityBeijing 100875 China Key Laboratory of Land Surface Pattern and Simulation Institute of Geographic Sciences and Natural Resources Research CASBeijing 100101 China

The cultivation of mountainous land results in water loss and soil erosion. With rapid urbanization and industrialization in China, labor emigration relieves the cultivation of mountainous areas in regions with high poverty and leads to a significant land use transition. This research built an analysis framework for 'land use transition – driving mechanism – effects –responses' for mountainous areas of China undergoing land use transition and then proposed the direction of mountainous land consolidation. The results showed that the turning point of land use morphology was the core of rural land use transition in mountainous areas. The expansion of cropland and the contraction of forestland have transitioned to the abandonment of cropland and the expansion of forestland;this transition was the main characteristic of the dominant land use change. land marginalization and land ecological functional recovery were the main characteristics of the recessive land use transition in mountainous areas. Socioeconomic factors were the primary driving forces during land use transition in mountainous areas, with labor emigration being the most direct force. The rising costs of farming and the challenging living conditions causing labor emigration were fundamental driving forces. Rural land use transition in mountainous areas reduced the vulnerability of the ecological function of land ecosystems. The advantages and disadvantages of the socioeconomic effects should focus on rural development of mountainous areas as well as the livelihood of farmers;this should be further supported by empirical and quantitative research. Rural land use transition of mountainous areas improves natural restoration and is related to socioeconomic development. Rural land consolidation of mountainous areas should conform to land use transition,with the goal of shifting from the increase of cultivated land to the synergies of ecological and environmental protection.

关键词： land use transition driving force effect land consolidation mountainous area

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Farmland Abandonment Research Progress: Influencing Factors and simulation Model

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Journal of Resources and Ecology 2019年第4期10卷 345-352页

作者： SONG Wei ZHANG Ying Key Laboratory of Land Surface Pattern and Simulation Institute of Geographic Sciences and Natural Resources Research Chinese Academy of Sciences Beijing 100101 China Chinese Academy of Surveying & Mapping Beijing 100830 China

Farmland abandonment is a global problem and considered one of the most important areas in land use change research. Farmland abandonment research currently focuses on understanding the factors that affect farmland abandonment and developing scientific models to simulate farmland abandonment. The study reviewed the natural and political factors driving farmland abandonment and summarized the main models for farmland abandonment simulation together with their advantages and disadvantages. We discuss the main ecological effects of farmland abandonment and propose farmland abandonment research directions. The study found that:(1) the influence of labor cost change and ageing labor force on farmland abandonment needs further investigation,(2) simulation models for farmland abandonment must include the decision-making mechanism of individual farmers and focus on macro large-scale abandonment prediction models, and(3) the influence of farmland abandonment on landscape culture must be investigated in detail.

关键词： farmland abandonment driving factors model simulation eco-environmental effects research progress

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Urban structural evolution over a century in Changchun city, Northeast China

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Journal of Geographical Sciences 2018年第12期28卷 1877-1895页

作者：匡文慧颜凤芹 Key Laboratory of Land Surface Pattern and Simulation Institute of Geographic Sciences and Natural Resources Research CAS Northeast Institute of Geography and Agroecology CAS

Knowledge on urban land-use change and its driving forces has vital significance in the practice of urban planning and management. However, the characteristics of historical, long-term changes and their quantitative relationships with the urban environment are still poorly understood. Based on multi-source data, including remote sensing imageries, large-scale topographic maps, historical maps, multi-temporal city maps, and other urban thematic maps, high-quality spatial information on urban land use in the built-up area of Changchun has been extracted for 1898, 1932, 1954, 1976, 1990, 2002, and 2012 by means of geographic information systems and remote sensing. We found that the land-use structure and spatial configuration has undergone tremendous alterations according to urban function in the 100-year history of Changchun city. The built-up area of Changchun expanded from 2.26 km^2 in 1898 to 328.12 km^2 in 2012, increasing about 144 times over the past century. Historically, the development of Changchun can be categorized into three stages: the initial forming stage, the old industrial development stage, and the modern metropolis development stage. Commercial and industrial land expanded rapidly following the founding of the People's Republic of China in 1949, with an increase from 1.74 km^2 in 1954 to 15.91 km^2 in 2012, and from 16.45 km^2 in 1954 to 107.05 km^2 in 2012, respectively. Although there was substantial growth in residential land use(from 1.81 km^2 in 1898 to 113.95 km^2 in 2012), the area percentage of residential land decreased continuously(from 80.09% in 1898 to 34.73% in 2012). Moreover, it was noted that the spatial configuration and structural percentage for commercial, industrial, and residential lands and others had tremendous divergences at different stages. These divergences of land-use structure occurred between the stages and were associated with social regimes and the functional orientation of urban society across the 100 years of histor

关键词： urban expansion land use urban structure driving factors Changchun city China

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Phytotoxic Effect of Yttrium-Oxide Nanoparticles on the Morphology, Oxidative Stress and Growth of Tomato Seedlings ( Lycopersicon Esculentum )

SSRN

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SSRN 2022年

作者： Wang, Xueping Liu, Xiaojie Wang, Lingqing Yang, Xiao Yang, Jun Yan, Xiulan Liang, Tao Hansen, Hans Chr Bruun Yousaf, Balal Shaheen, Sabry M. Bolan, Nanthi Rinklebe, Jörg Key Laboratory of Land Surface Pattern and Simulation Institute of Geographical Sciences and Natural Resources Research Chinese Academy of Sciences Beijing100101 China Sino-Danish College University of Chinese Academy of Sciences Beijing100049 China Department of Plant and Environmental Sciences University of Copenhagen Thorvaldsensvej 40 Frederiksberg CDK-1871 Denmark School of Earth and Space Sciences University of Science and Technology of China Anhui Hefei230026 China University of Wuppertal School of Architecture and Civil Engineering Institute of Foundation Engineering Water- and Waste-Management Laboratory of Soil- and Groundwater-Management Pauluskirchstraße 7 Wuppertal42285 Germany King Abdulaziz University Faculty of Meteorology Environment and Arid Land Agriculture Department of Arid Land Agriculture Jeddah21589 Saudi Arabia University of Kafrelsheikh Faculty of Agriculture Department of Soil and Water Sciences Kafr El-Sheikh33516 Egypt Faculty of Science University of Newcastle Callaghan NSW Australia Department of Environment Department of Environment and Energy Sejong University Seoul05006 Korea Republic of

The potential toxicity and ecological risk of rare-earth nanoparticles in the environment have received increasing attention due to their extensive application and inevitable releases. In this work, the physiological toxicity of yttrium oxide nanoparticles (Y2O3 NPs) at different levels (1, 5, 10, 20, 50 and 100 mg·L -1 ) was investigated on the typical commercial crop - tomatoes ( Lycopersicon esculentum ) seedlings. After the exposure of 15 days in Y2O3 NPs, the morphology, physiology, oxidative stress , and translocation mechanism were evaluated. Results revealed that Y2O3 NPs had phytotoxic impacts on germination of seeds and similar phytotoxic effects on morphology (i.e., bud elongation, root elongation and root activity), physiology (i.e., chlorophyll, superoxide dismutase and soluble protein content) and oxidative stress (proline, malondialdehyde). The inhibition rates of different concentrations of Y2O3 NPs in shoot biomass and root biomass varied from 0.2% to 6.3% and 1.0% to 11.3%, respectively. The translocation factor elucidated that Y2O3 NPs significantly suppressed tomato seedlings' shoot and root growth and transferred from root to shoot. These observations were consistent with the process of concentration-dependent uptake, bioaccumulation factor and confirmed by the transmission electron microscopy image. These results illustrated that Y2O3 NPs penetrated the epidermis and entered the cell wall, which occurred in intercellular space and cytoplasm of the mesophyll cell of tomato seedlings by endocytosis. Partial least squares structural equation modeling revealed that the concentration of NPs significantly negatively affects the morphology and physiology, leading to the change of biomass of plants. This study points out that the phytotoxic effect of Y2O3 NPs on morphology, physiology, oxidative stress, and translocation mechanism of tomatoes seedlings demonstrate the possible food chain transfer of Y 2 O 3 NPs. © 2022, The Authors. All rights reserved

关键词： Toxicity

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Analysis of differentiation effect of surface thermal environment in intensive mining areas based on NDVI-DFI model

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Nongye Gongcheng Xuebao/Transactions of the Chinese Society of Agricultural Engineering 2020年第3期36卷 160-168页

作者： Hou, Chunhua Li, Fuping Feng, Yifan Gu, Haihong Yuan, Xuetao Song, Wen Liu, Huixin College of Mining Engineering North China University of Science and Technology Tangshan063210 China Hebei Key Laboratory of Mining Developmeng and Security Technology Tangshan063210 China Hebei Industrial Technology Institute of Mine Ecological Remediation Tangshan063210 China Co. Ltd. Qingdao266109 China Key Laboratory of Land Surface Pattern and Simulation Institute of Geographic Sciences and Natural Resources Research Chinese Academy of Sciences Beijing100101 China North China University of Science and Technology Library Tangshan063210 China

Currently, the dimidiate pixel model is used in most studies to discuss vegetation fractional coverage (VFC) and explore its relationship with urban heat islands. Few studies have used the three-component pixel model to invert vegetation fractional coverage (VFC) and discuss the relationship between VFC and the differentiation effect of the surface thermal environment in mining-intensive areas. In this study, VFC was inverted based on the normalized difference vegetation index (NDVI)-dry fuel index (DFI) three-component pixel model using landsat satellite remote sensing images from 2000 to 2018. Mixed pixels were decomposed into photosynthetic vegetation (PV), non-photosynthetic vegetation (NPV), and bare soil (BS). The radiative transfer equation (RTE) was used to invert the surface temperature. The basic principle of this method is to remove the atmospheric influence and use the atmospheric radiation transfer equation;surface heat radiation intensity observed by the satellite is converted to the corresponding surface temperature. The parameters involved are mainly atmospheric profile parameters and surface specific emissivity. Heat-island index (HI) was used to grade the mean LST of the 2000-2018 study area. The relationship between the spatial-temporal changes in VFC and the differentiation effect of the surface thermal environment in the study area was analyzed using hierarchical statistics, a red-blue difference image method, correlation analysis, and regression analysis. On this basis, the influence mechanism of spatial-temporal variation in the VFC on the differentiation effect of surface thermal environment was studied. The results showed that the NDVI-DFI feature space of the study area conformed to the basic assumption of the three-component pixel model. The correlation matrix showed that there was a strong correlation between the changes in land surface temperature (LST) and VFC (the fractional cover of PV, fractional cover of NPV, and fractional cover of

关键词： Remote sensing

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