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Impacts of horizontal resolution and downscaling on the USLE LS factor for different terrains

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International Soil and Water Conservation Research 2020年第4期8卷 363-372页

作者： Chunmei Wang Linxin Shan Xin Liu Qinke Yang richard m.cruse Baoyuan Liu Rui Li Hongming Zhang Guowei Pang Shaanxi Key Laboratory of Earth Surface System and Environmental Carrying Capacity Northwest UniversityXi'an710127PR China College of Urban and Environmental Sciences Northwest UniversityXi'an710127PR China Key Laboratory of National Forestry Administration on Ecological Hydrology and Disaster Prevention in Arid Regions Xi'an University of TechnologyXi'an 710048PR China Department of Agronomy Iowa State UniversityAmesIA50011USA Xi'an Institute of Prospecting and mapping Xi'an710054PRChina Faculty of Geographical Science Beijing Normal UniversityBeijing100875PR China State Key Laboratory of Soil Erosion and Dryland Farming on the Loess Plateau Institute of Soil and Water ConservationNorthwest A&F UniversityYangling712100ShaanxiPR China College of Information Engineering Northwest A&F UniversityYanglingShaanxi712100China

Slope length and slope steepness are critical topographic factors(L and S)in the Universal Soil Loss Equation(USLE)and Chinese Soil Loss Equation(CSLE)for soil erosion *** slope length and slope gradient are potentially sensitive to spatial resolution when calculated in a GIS *** resolution effect on the LS factor and approaches suitable for improving the LS factor at a coarse resolution have not been well *** address this problem,the LS factor at 5-m and 30-m resolution in twenty-four watersheds with various terrains was *** a downscale model based on matching of the lower resolution LS cumulative frequency curves to a higher resolution("Histogram matching"method)was tested for its potential to improve LS factor estimation *** the larger relief mountainous area,compared to 5-m resolution,the 30-m resolution generated LS was generally overestimated by more than 20%and in lower relief areas underestimated by more than 15%.This bias is less than 10%in medium relief *** downscale model improved LS factor estimates compared to the 30-m resolution estimate by more than 10%when comparing frequency distribution curves and more than 20%in mean values in larger relief *** downscale model worked well in all regions except for the low relief areas,which intuitively are the low soil erosion potential *** results of this research help quantify the uncertainty in soil erosion estimates and may ultimately help to improve the assessment of soil erosion through its impact on LS factor estimates,especially at regional and global scales.

关键词： LS factor SRTm Resolution Downscale USLE

Guest editorial-soil erosion assessment, tools and data: A special issue from the Global Symposium on soil Erosion 2019

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International Soil and Water Conservation Research 2020年第4期8卷 333-336页

作者： Clara Lefèvre richard m.cruse Lucia Helena Cunha dos Anjos Costanza Calzolari Nigussie Haregeweyn Global Soil Partnership Secretariat Food and Agriculture Organization of the United NationsViale delle Terme di CaracallaRomeItaly Department of Agronomy Iowa State UniversityAmesIA500011USA Department of Soils Federal University of Rio de JaneiroSeropédicaRJ23890-000Brazil Intergovernmental Technical Panel on Soils Food and Agriculture Organization of the United NationsRomeItaly CNR Institute for Bioeconomy Sesto FiorentinoItaly International Platform for Dryland Research and Education Tottori University1390 HamasakaTottori680-0001Japan

This special issue on soil erosion assessment,tools and data creation,consolidation and harmonization presents advances in soil erosion research with a focus on new tools that are being used to assess soil erosion *** publication includes eleven selected contributions presented at the Global Symposium on Soil Erosion(GSER,15-17 may 2019,Rome,Italy)dealing with erosion indicators'improvement,the use of remote sensing,nuclear techniques and geochemical fingerprinting as promising methods to assess soil losses,management practices that reduce soil erosion in vineyards and olive groves plantations and their modelling,and national and regional erosion assessments.

关键词： soil erosion dealing

Unpaved road erosion after heavy storms in mountain areas of northern China

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International Soil and Water Conservation Research 2022年第1期10卷 29-37页

作者： Chunmei Wang Baoyuan Liu Qinke Yang Guowei Pang Yongqing Long Lei Wang richard m.cruse Weiqin Dang Xin Liu Enheng Wang Shaanxi Key Laboratory of Earth Surface System and Environmental Carrying Capacity College of Urban and Environmental SciencesNorthwest UniversityXi'an710127PR China Key Laboratory of National Forestry and Grassland Administration on Ecological Hydrology and Disaster Prevention in Arid Regions Xi'an710048PR China Advanced Institute of Natural Sciences Beijing Normal University at ZhuhaiZhuhai519087PR China State Key Laboratory of Earth Surface Processes and Resource Ecology School of GeographyBeijing Normal UniversityBeijing100875PR China Department of Agronomy Iowa State UniversityAmesIA50011USA Suide Experimental Station for Soil and Water Conservation the Yellow River Conservancy CommissionYulinShaanxi719000PR China Key Laboratory of Sustainable Forest Ecosystem management-ministry of Education Northeast Forestry UniversityHarbinHeilongjiang150040PR China

more frequent extreme rainfall events associated with global climate change cause greater challenges for soil *** erosion occurs on many unpaved roads since these structures create important water flow paths during heavy *** present research aimed to investigate the intensity and influencing factors of unpaved road erosion under varied land use and management conditions(sloping cropland,terraced cropland,forest&grass).The erosion occurred in the watersheds contributing runoff water to roads after the greatest rainfall event recorded in the mountain area of northern China caused by Typhon *** research was conducted in an agricultural-forest-dominated watershed based on field investigation and UAV-based image analysis.A road erosion level classification standard was given according to the occurrence of rills,ephemeral gullies,and *** erosion happened on 67% of the unpaved roads;42% of them suffered moderate to severe erosion in which ephemeral gullies or gullies *** average erosion amount from these roads was 2280.75 t ha-1 and was significantly influenced by the watershed land use type and *** dominant factor governing unpaved road erosion associated with terraced cropland was vegetation coverage on *** area was the most important factor for road erosion in sloping cropland and forest&grass land,and road gradient was also a critical ***,and forest&grass in drainage areas significantly reduced unpaved road erosion by 85%and,47%,respectively,compared to sloping *** integrated measures should be used to prevent unpaved road *** results of this research can be applied to road protection against erosion in heavy storms.

关键词： Unpaved road erosion Heavy storm Gully Land management Climate change

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土壤侵蚀日发布系统

土壤与作物 2017年第4期6卷 312-319页

作者：陈学文 richard m.cruse Brian K.Gelder Timothy J.Sklenar Daryl E.Herzmann David E.James 李浩张兴义中国科学院东北地理与农业生态研究所黑土区农业生态重点实验室黑龙江哈尔滨150081 Iowa State University AmesIA 50011USA National Laboratory for Agriculture and Environment United States Department of AgricultureAmesIA 50011USA

土壤侵蚀发布系统作为定量研究土壤侵蚀过程的重要工具,一直是土壤侵蚀学科的前沿领域,其对于估算土壤流失速度、评估水土保持措施效益具有重要的科学意义。然而,现有土壤侵蚀发布系统多仅依靠一年内降雨事件或利用多年平均降雨数据进... 详细信息

土壤侵蚀发布系统作为定量研究土壤侵蚀过程的重要工具,一直是土壤侵蚀学科的前沿领域,其对于估算土壤流失速度、评估水土保持措施效益具有重要的科学意义。然而,现有土壤侵蚀发布系统多仅依靠一年内降雨事件或利用多年平均降雨数据进行潜在土壤侵蚀程度估算,无法对一次平均水平的土壤侵蚀事件进行定量描述,更无法回答土壤侵蚀在何时何地发生,侵蚀动态如何变化,以及降雨、地形、土壤、作物管理方式和极端事件的时空变化对土壤侵蚀的影响。作为土壤侵蚀发布系统领域最新研究进展的土壤侵蚀日发布系统DEP(Daily Erosion Project),解决了以往土壤侵蚀发布系统中出现的上述问题。DEP基于侵蚀模型、地理信息、土地利用、植被变化等信息,逐日模拟降雨、径流、剥离、土壤流失等定量指标,结合第二代气象雷达云图生成土壤侵蚀分布图,实现以日为步长的土壤侵蚀发布,成为首个土壤侵蚀日发布系统,已在美国成功应用。本文详细介绍了土壤侵蚀日发布系统,并对实例进行了分析,探讨了该系统在我国土壤侵蚀发布研究与应用中的前景。

关键词：土壤侵蚀发布系统 WEPP 激光雷达第二代气象雷达数字高程模型支流集水区

Effects of Topography and Land Use Change on Gully Development in Typical mollisol Region of Northeast China

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Chinese Geographical Science 2016年第6期26卷 779-788页

作者： LI Hao richard m.cruse LIU Xiaobing ZHANG Xingyi Key Laboratory of mollisols Agroecology Northeast Institute of Geography and AgroecologyChinese Academy of SciencesHarbin 150081China University of Chinese Academy of Sciences Beijing 100049China Department of Agronomy lowa State UniversityAmes500011 lowaUSA

Due to high intensity agricultural exploitation since the middle of the 20 th century, farmland gullies have become a pervasive form of water erosion in Northeast China. Yet few researches are concentrated on how topography and land use affect long-term gully development in this region. In this study, gully distribution in a village with an area of 24.2 km^2 in the central mollisols area of Northeast China in different times were compared by Aerial photography(1968), Quickbird image(2009) and field survey, and factors affecting gully development including land use and topography were analyzed. The results showed that the total gully number decreased from 104 to 69, while occupying area rose from 34.8 ha to 78.4 ha from 1968 to 2009. Fundamental gully distribution had been formed by 1968 as most of 2009′s gullies were evolved from 1968′s gullies′ merge and width expansion process, and new gullies those initiated after 1968 occupied only 7% of total gully area in 2009. Gully area increasing ratio in grassland was the highest and that in forestland was the lowest. The threshold catchment area between simple and complex gully development was around 15 ha to 25 ha. This threshold value sets apart catchment areas that will develop simple or complex gullies in areas with similar environmental conditions. Gully control measurements were urgent because if appropriate gully control implements would not be applied, present gully erosion crisis could be doubled within 50 years.

关键词： gully erosion land use topographic threshold mollisols Northeast China

mollisols Properties and Changes in Ukraine and China

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Chinese Geographical Science 2011年第3期21卷 257-266页

作者： Yuri S KRAVCHENKO ZHANG Xingyi LIU Xiaobing SONG Chunyu richard m.cruse Key Laboratory of mollisols Agroecology Northeast Institute of Geography and Agroecology Chinese Academy of Sciences Harbin 150081 China National University of Life and Environmental Sciences of Ukraine Kyiv 03041 Ukraine Department of Agronomy Iowa State University Ames 500011 IA USA

Soils are the foundation of civilizations and the basis for human food *** in Ukraine and Northeast China are two out of the four major mollisol regions in the *** natural areas from which mollisols developed are the prairies and steppes that experience temperate and freezing *** review paper introduces the general climate,vegetation,and topography of mollisols regions in Ukraine and Northeast China,analyzes their properties,including soil texture,soil organic matter content,soil bulk density,pH,cation exchange capacity and other chemical properties,and compares the property changes and management practices of mollisols in relation to sustainable grain production.

关键词： mollisols soil properties soil organic matter tillage mollisols management

Call for joint international actions to improve scientific understanding and address soil erosion and riverine sediment issues in mountainous regions

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International Soil and Water Conservation Research 2023年第3期11卷 586-588页

作者： Fan Zhang Baoyuan Liu Liping Zhu richard cruse Dongfeng Li Panos Panagos Pasquale Borrelli Yakov Kuzyakov Shaoshan An State Key Laboratory of Tibetan Plateau Earth System Environment and Resources(TPESER)Institute of Tibetan Plateau ResearchChinese Academy of SciencesBeijingChina Beijing Normal University BeijingChina Agronomy Department at Iowa State University AmesIAUnited States Department of Geography National University of SingaporeKent RidgeSingapore European Commission Joint Research CentreIspraItaly Department of Environmental Sciences Environmental GeosciencesUniversity of BaselBaselSwitzerland Department of Science Roma Tre UniversityRomeItaly Department of Soil Science of Temperate Ecosystems Department of Agricultural Soil ScienceGeorg-August-University of GottingenGermany Research Center of Water and Soil Conservation and Ecological Environment Chinese Academy of Sciences&Ministry of EducationYanglingShaanxiChina

During the International Workshop on Soil Erosion and Riverine Sediment in mountainous Regions held in November 2022,scientists from many countries shared their state-of-the-art knowledge and brainstormed to improve scientific understanding for coping with climate change and anthropogenic *** summarized in this discussion includes proposed key scientific questions and suggested joint actions to reduce soil erosion and riverine sediment problems in mountainous regions.

关键词： soil mountainous summarized

Understanding Science Through the Computational Lens

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Journal of Computer Science & Technology 2011年第4期26卷 569-577页

作者： richard m.Karp Department of Electrical Engineering and Computer Sciences University of California

This article explores the changing nature of the interaction between computer science and the natural and social sciences. After briefly tracing the history of scientific computation, the article presents the concept of computational lens, a metaphor for a new relationship that is emerging between the world of computation and the world of the sciences. Our main thesis is that, in many scientific fields, the processes being studied can be viewed as computational in nature, in the sense that the processes perform dynamic transformations on information represented as digital data. Viewing natural or engineered systems through the lens of their computational requirements or capabilities provides new insights and ways of thinking. A number of examples are discussed in support of this thesis. The examples are from various fields, including quantum computing, statistical physics, the World Wide Web and the Internet, mathematics, and computational molecular biology.

关键词： computational process computer science and other sciences computational lens

metamorphic consequences of secular changes in oceanic crust composition and implications for uniformitarianism in the geological record

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Geoscience Frontiers 2018年第4期9卷 1009-1019页

作者： richard m.Palin Brendan Dyck Department of Geology and Geological Engineering Colorado School of Mines Department of Earth Sciences Simon Fraser University

Cooling of the Earth＇s mantle since the meso-Archean is predicted by thermal and petrological models to have induced a secular change in the composition of primary mantle-derived magmas-and thus bulk oceanic crust; in particular, suggesting a decrease in maficity over time. This hypothesis underpins several recent studies that have addressed key geological questions concerning evolving plate tectonic styles, the rates and timing of continental crust formation, comparative planetology, and the emergence of complex life on Earth. major, minor, and trace element geochemical analyses of（meta）mafic rocks preserved in the geological record allows exploration of this theory, although no consensus currently exists about the magnitude of this change and what compositions-if anything-constitute representative examples of Paleo-, meso-, or Neo-Archean primitive oceanic crust. In this work, we review the current state of understanding of this issue, and use phase equilibria to examine the different mineral assemblages and rock types that would form during metamorphism of basalt of varying maficity in subduction zone environments. The presence（or absence） of such metamorphic products in the geological record is often used as evidence for（or against） the operation of modern-day subductiondriven plate tectonics on Earth at particular time periods; however, the control that secular changes in composition have on the stability of mineral assemblages diagnostic of subduction-zone metamorphism weakens such uniformitarianistic approaches. Geodynamic interpretations of the Archean metamorphic rock record must therefore employ a different set of petrological criteria for determining tectonothermal histories than those applied to Proterozoic or Phanerozoic equivalents.

关键词： Archean mantle cooling Oceanic crust Basalt metamorphism Uniformitarianism