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Fine classification of rice paddy using multitemporal compact polarimetric SAR C band data based on machine learning methods

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Frontiers of Earth Science 2024年第1期18卷 30-43页

作者： Xianyu GUO Junjun YIN Kun LI Jian YANG Huimin ZOU Fukun YANG School of Computer and Communication Engineering University of Science and Technology BeijingBeijing 100083China Aerospace Information Research Institute Chinese Academy of SciencesBeijing 100094China department of Electronic Engineering Tsinghua UniversityBeijing 100084China College of global change and Earth System Science Beijing Normal UniversityBeijing 100875China

Rice is an important food crop for human *** distinguishing different varieties and sowing methods of rice on a large scale can provide more accurate information for rice growth monitoring,yield estimation,and phenological monitoring,which has significance for the development of modern *** polarimetric(CP)synthetic aperture radar(SAR)provides multichannel information and shows great potential for rice monitoring and ***,the use of machine learning methods to build classification models is a controversial *** this paper,the advantages of CP SAR data,the powerful learning ability of machine learning,and the important factors of the rice growth cycle were taken into account to achieve high-precision and fine classification of rice ***,CP SAR data were simulated by using the seven temporal RADARSAT-2 C-band data ***,20-two CP SAR parameters were extracted from each of the seven temporal CP SAR data *** addition,we fully considered the change degree of CP SAR parameters on a time scale(ΔCP_(DoY)).Six machine learning methods were employed to carry out the fine classification of rice *** results show that the classification methods of machine learning based on multitemporal CP SAR data can obtain better results in the fine classification of rice paddies by considering the parameters ofΔCP_(DoY).The overall accuracy is greater than 95.05%,and the Kappa coefficient is greater than *** them,the random forest(RF)and support vector machine(SVM)achieve the best results,with an overall accuracy reaching 97.32%and 97.37%,respectively,and Kappa coefficient values reaching 0.965 and 0.966,*** the two types of rice paddies,the average accuracy of the transplant hybrid(T-H)rice paddy is greater than 90.64%,and the highest accuracy is 95.95%.The average accuracy of direct-sown japonica(D-J)rice paddy is greater than 92.57%,and the highest accuracy is 96.13%.

关键词： compact polarimetric(CP)SAR rice paddy machine learning fine classification multitemporal

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Embryonic thermal manipulation:a potential strategy to mitigate heat stress in broiler chickens for sustainable poultry production

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Journal of Animal Science and Biotechnology 2024年第4期15卷 1347-1375页

作者： Sadid Al Amaz Birendra Mishra department of human Nutrition Food and Animal SciencesCollege of Tropical Agriculture and Human ResourcesUniversity of Hawaii at ManoaAgSci 2161955 East‑West RdHonoluluHI 96822USA

Due to high environmental temperatures and climate change, heat stress is a severe concern for poultry health and production, increasing the propensity for food insecurity. With climate change causing higher temperatures and erratic weather patterns in recent years, poultry are increasingly vulnerable to this environmental stressor. To mitigate heat stress, nutritional, genetic, and managerial strategies have been implemented with some success. However, these strategies did not adequately and sustainably reduce the heat stress. Therefore, it is crucial to take proactive measures to mitigate the effects of heat stress on poultry, ensuring optimal production and promoting poultry well-being. Embryonic thermal manipulation(TM) involves manipulating the embryonic environment's temperature to enhance broilers' thermotolerance and growth performance. One of the most significant benefits of this approach is its cost-effectiveness and saving time associated with traditional management practices. Given its numerous advantages, embryonic TM is a promising strategy for enhancing broiler production and profitability in the poultry industry. TM increases the standard incubation temperature in the mid or late embryonic stage to induce epigenetic thermal adaption and embryonic metabolism. Therefore, this review aims to summarize the available literature and scientific evidence of the beneficial effect of pre-hatch thermal manipulation on broiler health and performance.

关键词： Broiler Embryo Epigenetics global warming Thermoregulation

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changes in albedo and its radiative forcing of grasslands in East Asia drylands

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Ecological Processes 2024年第1期13卷 237-251页

作者： Qingsong Zhu Jiquan Chen Liangxu Wu Yuting Huang Changliang Shao Gang Dong Zhe Xu Xianglan Li State Key Laboratory of Remote Sensing Science College of Global Change and Earth System Science Faculty of Geographical ScienceBeijing Normal University department of Geography Environment and Spatial Sciences Michigan State University State Key Laboratory of Efficient Utilization of Arid and Semi-Arid Arable Land in Northern China National Hulunber Grassland Ecosystem Observation and Research Station Institute of Agricultural Resources and Regional Planning Chinese Academy of Agricultural Sciences School of Life Science Shanxi University

Background Grasslands in drylands are increasingly influenced by human activities and climate change, leading to alterations in albedo and radiative energy balance among others. Surface biophysical properties and their interactions change greatly following disturbances. However, our understanding of these processes and their climatic impacts remains limited. In this study, we used multi-year observations from satellites and eddy-covariance towers to investigate the response of albedo to variables closely associated with human disturbances, including vegetation greenness（EVI） and surface soil volumetric water content（VWC）, as well as snow cover and clearness index（Ta） for their potential *** EVI and VWC during the growing season were the primary factors influencing albedo. EVI and VWC were negatively correlated with albedo, with VWC's total direct and indirect impacts being slightly smaller than those of EVI. During the non-growing season, snow cover was the most influential factor on albedo. VWC and Ta negatively affected albedo throughout the year. We estimated the impact of variations in EVI and VWC on climate to be in the range of 0.004 to 0.113 kg CO2m-2yr-1in *** This study indicates the significant impacts of climate change and human disturbances on vulnerable grassland ecosystems from the perspective of altered albedo. changes in vegetation greenness and soil properties induced by climate change and human activities may have a substantial impact on albedo, which in turn feedback on climate change, indicating that future climate policies should take this factor into consideration.

关键词： Albedo global warming potential Grassland Disturbance

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Regulating the electronic structure of Ir single atoms by ZrO_(2)nanoparticles for enhanced catalytic oxidation of formaldehyde at room temperature

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Chinese Chemical Letters 2024年第7期35卷 200-205页

作者： Shiqi Peng Yongfang Rao Tan Li Yufei Zhang Jun-ji Cao Shuncheng Lee Yu Huang Key Laboratory of Aerosol Chemistry&Physics State Key Laboratory of Loess and Quaternary Geology(SKLLQG)Institute of Earth EnvironmentChinese Academy of Sciences(CAS)Xi’an 710061China School of human Settlements and Civil Engineering Xi’an Jiaotong UniversityXi’an 710049China department of Environmental Science and Engineering Xi’an Jiaotong UniversityXi’an 710049China Faculty of Chemical Engineering Kunming University of Science and TechnologyKunming 650500China School of Environment and Energy South China University of TechnologyGuangzhou 51006China School of Environmental and Municipal Engineering Xi’an University of Architecture and TechnologyXi’an 710055China Institute of Atmospheric Physics Chinese Academy of SciencesBeijing 100190China department of Civil and Environmental Engineering The Hong Kong Polytechnic UniversityHong KongChina CAS Center for Excellence in Quaternary Science and global change Xi’an 710061China

Developing low-loading single-atom catalysts with superior catalytic activity and selectivity in formaldehyde(HCHO)oxidation at room temperature remains ***,ZrO_(2)nanoparticles coupled low-loading Ir single atoms in N-doped carbon(Ir_(1)-N-C/ZrO_(2))was *** optimal Ir_(1)-N-C/ZrO_(2)with 0.25 wt%Ir loading delivers the high HCHO removal and conversion efficiency(>95%)at 20℃,which is higher than that over Ir_(1)-N-C with the same Ir *** specific rate can reach 1285.6 mmol gIr^(-1)h^(-1),surpassing the Ir based catalysts reported to *** functional theory calculation results and electron spin resonance spectra indicate that the introduction of Zr O_(2)nanoparticles modulate the electronic structure of the Ir single atoms,promoting O_(2)activation to·O_(2)^(–).Moreover,the Ir-C-Zr channel is favorable for the dissociation of·O_(2)^(–)to active oxygen atom(*O),and further accelerates the transformation of HCHO and intermediates(dioxymethylene and formates)to CO_(2)and H_(2)*** work provides a facile strategy to design low-loading single-atom catalysts with high catalytic activity toward HCHO oxidation.

关键词： ZrO_(2)nanoparticles Ir single atoms Electronic structure Formaldehyde Catalytic oxidation

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Toward development of ecosystem asset accounts at the national level

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Ecosystem Health and Sustainability 2019年第1期5卷 36-46,I0022页

作者： Dava Vačkářů Ioanna Grammatikopoulou department of human dimensions of global change Global Change Research Institute of the Czech Academy of SciencesBrnoCzech Republic

Ecosystem accounting has become one of the key components in the revision of international statistical *** of the System of Environmental-Economic Accounting for ecosystem services follows the rapid progress of science in this area as well as expanding applications to sustainability *** this contribution,we discuss approaches to accounting of ecosystem assets as a natural capital basis that is critical for ecosystem service *** on examples from the Czech Republic,a Central European country,we illustrate the construction of ecosystem extent accounts based on the methodology of Land and Ecosystem *** analysis is complemented by monetary ecosystem asset accounting through quantification of the present value of future ecosystem service *** condition is represented by the Mean Species Abundance indicator,which gauges the direction of ecosystem *** on the demonstration of approaches to ecosystem asset accounting,we discuss selected aspects of ecosystem condition measurements,valuation,and policy implications of ecosystem asset accounting at the national level.

关键词： Ecosystem accounting ecosystem services land cover change Mean Species Abundance value transfer Czech Republic

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自然湖泊主导全球地表水量变化

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Science Bulletin 2024年第8期69卷 1016-1019页

作者：徐南卢麾李纹宇宫鹏 College of Geography and Remote Sensing Jiangsu Province Engineering Research Center of Water Resources and Environment Assessment Using Remote Sensingand Key Laboratory of Hydrologic-Cycle and Hydrodynamic-System of Ministry of Water ResourcesHohai UniversityNanjing 210098China department of Earth System Science Institute of Global Change StudiesTsinghua UniversityBeijing 100084China department of Geography and Planning University of TorontoToronto ON M5S 3G3Canada department of Geography Department of Earth ScienceUniversity of Hong KongHong Kong 999077China State Key Laboratory of Hydroscience and Engineering Tsinghua UniversityBeijing 100084China Tsinghua University(department of Earth System Science)-Xi’an Institute of Surveying and Mapping Joint Research Center for Next-Generation Smart Mapping Beijing 100084China

Although land surface water only covers a small portion(~3.7%) of our planet,it plays many essential roles:e.g.,freshwater storage,industrial consumption,agricultural irrigation,and biodiversity maintenance [1,2].Water storage variability is associated with various natural processes and human activities on the Earth [3,4] and it is well known that reservoir regulation is the most widely distributed and fundamental human activity capable of altering the global water *** recent years,through reservoir regulation,humans have been able to obtain more freshwater from the Earth’s surface,with great benefits to human ***,however,the extent to which human activities affect the global water cycle remains *** a result,there is an urgent need to quantify and understand the role of human activities in the global water cycle to ensure that freshwater resources are managed sustainably at the global scale.

关键词： reservoir Earth planet

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Triazine-based multicomponent metallacages with tunable structures for SO_(2) selective capture and conversion

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Aggregate 2024年第1期5卷 270-279页

作者： Ruoqian Zhang Dingyue Hu Yu Fu Qian Feng Chaoqun Mu Kai Gao Heping Ma Ming Liu Mingming Zhang State Key Laboratory for Mechanical Behavior of Materials Shaanxi International Research Center for Soft MatterSchool of Materials Science and EngineeringXi’an Jiaotong UniversityXi’anP.R.China department of Chemistry Hangzhou Global Scientific and Technological Innovation Center(HIC)Zhejiang UniversityHangzhouP.R.China School of Chemical Engineering and Technology Xi’an Jiaotong UniversityXi’anP.R.China

The design of novel materials for sulfur dioxide(SO_(2))capture and conversion with considerable efficiency under mild conditions is of great significance for human health and environmental protection yet highly ***,we report a series of triazine-based multicomponent metallacages via coordination-driven self-assembly of 2,4,6-tri(4-pyridyl)-1,3,5-triazine,cis-Pt(PEt3)2(OTf)2 and different tetracarboxylic *** the increase of the length of the tetracarboxylates,the structures of the metallacages change from pyramids to extended *** to their N-rich structure,these metallacages are further used for selective SO_(2)capture,showing good adsorption capacity and remarkable SO_(2)/CO_(2)selectivity in ambient conditions,suggesting their potential applications toward real flue gas *** metallacages are further employed for the conversion of SO_(2)into value-added compounds,showing exceptional efficiency even dilute SO_(2)is used as the *** study represents a type of structure-tunable triazinebased metallacages for SO_(2)capture and conversion,which will pave the way on the applications of metal-organic complexes for gas adsorption.

关键词： multicomponent metallacages self-assembly SO_(2) adsorption SO_(2) conversion tunable structures

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大陆岩石圈与地球深部动力过程的协同演化

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科学通报 2024年第2期69卷 200-214页

作者：刘丽军陈凌中国科学院地质与地球物理研究所岩石圈演化国家重点实验室北京100029 department of Earth Science and Environmental change University of Illinois at Urbana-ChampaignUrbana IL 61801USA 中国科学院大学地球与行星科学学院北京100049

陆地是人类最主要的栖息地,然而其下方岩石圈的性质仍存在很多未知的因素.传统的板块构造理论认为大陆漂移是受大洋板块运动所控制,大陆岩石圈与对流地幔的物质交换局限在板块边界或热点附近,而大陆内部,尤其是克拉通的构造变形主要是... 详细信息

陆地是人类最主要的栖息地,然而其下方岩石圈的性质仍存在很多未知的因素.传统的板块构造理论认为大陆漂移是受大洋板块运动所控制,大陆岩石圈与对流地幔的物质交换局限在板块边界或热点附近,而大陆内部,尤其是克拉通的构造变形主要是大陆岩石圈对深部动力过程的被动响应.该认识的一个理论基础是tectosphere模型,即大陆内部的克拉通岩石圈地幔密度小而黏度高,从而能够长期稳定存在.然而近期的研究表明,克拉通岩石圈并非如传统认为的长期保持稳定,很多克拉通都发生过不同程度的结构改变,甚至破坏.相应地,对克拉通岩石圈地幔动力学性质的认知也在发生重大转变,如发现其密度高于周围地幔并且具有分层性,而其内部也存在不同尺度的薄弱带/层,在特定的构造扰动下,克拉通岩石圈会发生失稳而形成大规模拆沉.因此,本文认为,大陆岩石圈与深部地幔在超大陆时间尺度上是协同演化的,前者可以通过拆沉和折返的形式主动参与地幔对流,进而更加深刻地影响深浅能量和物质交换.这一认识的转变表明,大陆岩石圈对深部动力过程具有主动作用,因此我们对固体地球演化、环境气候变迁等重大问题的探索需要更多地引入大陆岩石圈本身的贡献.

关键词：大陆岩石圈大洋俯冲地幔柱拆沉深浅耦合协同演化

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A U.S.‒China coal power transition and the global 1.5℃ pathway

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Advances in Climate change Research 2022年第2期13卷 179-186页

作者： Ryna Yiyun CUI Nathan HULTMAN Di-Yang CUI Haewon MCJEON Leon CLARKE Jia-Hai YUAN Wen-Jia CAI Center for global Sustainability School of Public PolicyUniversity of MarylandCollege ParkMD20742USA Joint global change Research Institute Pacific Northwest National LaboratoryCollege ParkMD20740USA School of Economics and Management North China Electric Power UniversityBeijing102206China department of Earth System Science Tsinghua UniversityBeijing100084China

As the world seeks to increase ambition rapidly to limit global warming to 1.5℃,joint leadership from the world's largest greenhouse gas(GHG)emitters-the United States(U.S.)and China-will be critical to deliver significant emissions reductions from their own countries as well as to catalyze increased international *** a period of uncertainty in international climate policy,these countries now both have current leadership that supports ambitious climate *** this context,a feasible,high-impact,and potentially globally catalytic agreement by the *** China to transition away from coal to clean energy would be a major contribution toward this global *** undertake a plant-by-plant assessment in the power sector to identify practical coal retirement pathways for each country that are in line with national priorities and the global 1.5℃ *** plant-by-plant analysis shows that the 1.5℃-compatible pathways may result in an average retirement age of 47 years for the *** plants and 22 years for Chinese coal plants,raising important questions of how to compare broader economic,employment,and social *** also demonstrate that such pathways would also lead to significant emissions reductions,lowering overall global energy-related CO_(2) emissions by about 9%in 2030 relative to 2020.A catalytic effect from the possibility of other countries taking compatible actions is estimated to reduce global emissions by 5.1 Gt CO_(2) in 2030 and by 10.1 Gt CO_(2) in 2045.

关键词： U.S.‒China Coal power transition Climate mitigation Paris agreement Integrated assessment modeling

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Indoor air particles in research vessel from Shanghai to Antarctic: Characteristics, influencing factors, and potential controlling pathway

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Journal of Environmental Sciences 2023年第4期126卷 784-793页

作者： Xudong Wu Fange Yue Jiancheng Wang Xiawei Yu Hongwei Liu Weihua Gu Mingming Han Juan Li Zhouqing Xie Anhui Key Laboratory of Polar Environment and global change Department of Environmental Science and EngineeringUniversity of Science and Technology of ChinaHefei 230026China department of Anesthesiology the First Affiliated Hospital of University of Science and Technology of ChinaHefei 230001China Center for Excellence in Urban Atmospheric Environment Institute of Urban EnvironmentChinese Academy of SciencesXiamen 361021China

Despite millions of seafarers and passengers staying on ships each year, few studies have been conducted on the indoor air quality inside ship hulls. In this study, we investigated the levels and size distribution of indoor particulate matter during two cruises of the research vessel “Xuelong” from Shanghai to Antarctica. The results showed that the particle size less than 2.5 μm(PM_(2.5)), and particle size less than 10 μm(PM_(10)) concentrations in different rooms of the ship widely varied. We observed high particulate matter(PM) levels in some of the rooms. The mass concentration distribution was dominated by 1–4 μm particles, which may have been caused by the hygroscopic growth of fine particles. The dominant factors influencing PM concentrations were indoor temperature, relative humidity, and human activity. We quantified contributions of these factors to the levels of indoor particles using a generalized additive model. In clean rooms, the levels of indoor particles were controlled by temperature and relative humidity, whereas in polluted rooms, the levels of indoor particles were mainly influenced by temperature and human activity, which implied that controlling temperature and human activity would efficiently reduce the levels of indoor particles.

关键词： Indoor air Ship Influencing factor Generalized additive model(GAM) Quantification Controlling pathway

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