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Modeling the impacts of temperature and precipitation changes on soil CO_2 fluxes from a Switchgrass stand recently converted from cropland

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Journal of Environmental sciences 2016年第5期28卷 15-25页

作者： Liming Lai Sandeep Kumar Rajesh Chintala Vance N. Owens David Clay Joseph Schumacher Abdul-Sattar Nizami Sang Soo Lee Rashad Rafique department of Plant Science South Dakota State University Brookings South Dakota 57007 USA. North Central Sun Grant Center South Dakota State University Brookings South Dakota 57007 USA Center of Excellence in Environmental Studies (CEES) King Abdulaziz University Abdullah Sulayman Jeddah 22254 Saudi Arabia kangwon National University Chuncheon 200-701 South Korea Joint global Change Research Institute Pacific Northwest National Lab College Park Maryland 20740 USA

Switchgrass（Panicum virgatum L.） is a perennial C_4 grass native to North America and successfully adapted to diverse environmental conditions. It offers the potential to reduce soil surface carbon dioxide（CO_2） fluxes and mitigate climate change. However, information on how these CO_2 fluxes respond to changing climate is still lacking. In this study, CO_2 fluxes were monitored continuously from 2011 through 2014 using high frequency measurements from Switchgrass land seeded in 2008 on an experimental site that has been previously used for soybean（Glycine max L.） in South Dakota, USA. DAYCENT, a process-based model, was used to simulate CO_2 fluxes. An improved methodology CPTE[Combining Parameter estimation（PEST） with ＂Trial and Error＂ method] was used to calibrate DAYCENT. The calibrated DAYCENT model was used for simulating future CO_2 emissions based on different climate change scenarios. This study showed that：（i） the measured soil CO_2 fluxes from Switchgrass land were higher for 2012 which was a drought year, and these fluxes when simulated using DAYCENT for long-term（2015–2070） provided a pattern of polynomial curve;（ii） the simulated CO_2 fluxes provided different patterns with temperature and precipitation changes in a long-term,（iii） the future CO_2 fluxes from Switchgrass land under different changing climate scenarios were not significantly different, therefore, it can be concluded that Switchgrass grown for longer durations could reduce changes in CO_2 fluxes from soil as a result of temperature and precipitation changes to some extent.

关键词： Carbon dioxide Switchgrass DAYCENT Climate change

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Assessing the costs and benefits of improved land management practices in three watershed areas in Ethiopia

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International soil and Water Conservation Research 2016年第1期4卷 20-29页

作者： Abonesh Tesfaye Roy Brouwer Pieter van der Zaag Workneh Negatu department of Environmental Economics Institute for Environmental StudiesVU University AmsterdamDe Boelelaan 10871081 HV AmsterdamThe Netherlands UNESCO–IHE Institute for Water EducationDelftThe Netherlands Delft University of Technology DelftThe Netherlands Addis Ababa University College of Development StudiesCentre for Rural DevelopmentAddis AbabaEthiopia

Unsustainable land use management and the resulting soil erosion are among the most pervasive problems in rural Ethiopia,where most of the country’s people live,jeopardizing food *** various efforts to introduce soil conservation measures and assess their costs and benefits,it is unclear how efficient these measures are from an economic point of view in securing food *** paper examines the costs and benefits of three soil conservation measures applied in the country in three different rural districts facing different degrees of soil erosion problems using survey data collected from 750 farm households.A production function is estimated to quantify the costs and benefits of more sustainable land use management *** show that the soil conservation measures significantly increase productivity and hence food *** the costs and benefits,the results indicate that implementing soil conservation measures would benefit farm communities in the case study areas through increased grain productivity and food security.

关键词： soil conservation Cost–benefit analysis Cobb–Douglas production function Blue Nile Ethiopia

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陕北不同沟道土地盐碱化现状及影响因素

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地球环境学报 2020年第1期11卷 81-89页

作者：陈淑敏金钊张晶褚光琛桑维峻林杭生中国科学院地球环境研究所黄土与第四纪地质国家重点实验室西安710061 中国科学院大学北京100049 中国科学院第四纪科学与全球变化卓越创新中心西安710061 department of Ecosystem Science and management the Pennsylvania State UniversityUniversity ParkPA 16802USA

沟道土地是陕北黄土丘陵沟壑区重要的土地资源。然而,当前对黄土高原沟道土地的盐碱化问题关注不够,对盐碱化的现状、发生机制和防治措施也缺乏深入系统的认识,知识储备不能满足生产实际的需要。本文以陕北黄土丘陵沟壑区自然和人为形... 详细信息

沟道土地是陕北黄土丘陵沟壑区重要的土地资源。然而,当前对黄土高原沟道土地的盐碱化问题关注不够,对盐碱化的现状、发生机制和防治措施也缺乏深入系统的认识,知识储备不能满足生产实际的需要。本文以陕北黄土丘陵沟壑区自然和人为形成的沟道土地为研究对象,分别是延安顾屯新造耕地(治沟造地)、延川马家湾淤地坝土地和子洲黄土洼天然古聚湫土地,在这些流域内沿沟道采集土壤样品,测定土壤的电导率(EC)、p H值、含水量及粒度,分析土壤盐碱化的现状和影响因子。结果表明:马家湾淤地坝土地盐碱化最为严重,流域中游至上游均出现不同程度的盐碱化;顾屯新造地上游出现盐碱化,盐碱化程度较马家湾轻,而黄土洼古聚湫全流域未出现盐碱化。地下水位较浅是沟道土地发生盐碱化的主要影响因素,因此陕北沟道土地盐碱化防治应着力控制地下水位,建设良好的排水系统,加强排水。

关键词：治沟造地淤地坝古聚湫地下水位土壤盐碱化黄土高原

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Sprinkler Irrigation and soil Tillage Practices in Sugarcane Plantations as Influenced by soil Texture and Water Storage in Northern Ivory Coast

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Journal of Life sciences 2013年第3期7卷 293-301页

作者： Crepin B. Pene, Souleymane N'Diaye Chantal N'Guessan-Konan department of R&D SUCAFCI/SOMDIAA Sugar Mills 33 rue des Brasseurs O1 P.O. Box 1967 Abidjan 01 Ivory Coast

soil survey investigations were carried out in Ferk6 1 as well as Ferk6 2 sugar mills of northern Ivory Coast to determine soil texture and water storage capacity for sprinkler irrigation and tillage management. A 5-year term observation experiment on reduced tillage compared with conventional tillage was also conducted in Ferk6 1 over an irrigated cane crop of 28 ha for yield optimization purpose. soil sampling was achieved after harvest or prior to re-plantation at five different spots along two transects over 30 cm depth in every farmland which covers about 30-40 ha with 432 m long cane rows as to get an average soil sample of 1.5-2 kg. soil physical properties like texture and water retention curves were determined locally in the sugar company＇s soil laboratory. It came out that the majority of soils investigated was coarse-textured for about 64% in Ferk6 1 and 85% in Ferk6 2, with a lower to medium water storage capacity （70-89 mm） over 60 cm depth which corresponds to a readily available moisture less than 60 mm. Except for the sugarcane plant crop, no significant difference in cane yields resulting from tillage practices was observed over four consecutive cropping seasons. The yield decline from plant cane to first ratoon was very high under conventional tillage （-16 t/ha） compared with the reduced tillage （＋3 t/ha）. Even higher cane yield was obtained on the second ratoon （89 t/ha） compared with the conventional tillage （83 t/ha）.

关键词： Particle size distribution physical property water retention available moisture reduced tillage irrigation management.

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A Large Scale GIS Geodatabase of soil Parameters Supporting the Modeling of Conservation Practice Alternatives in the United States

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Journal of Geographic Information System 2017年第3期9卷 267-278页

作者： Mauro Di Luzio Mike J. White Jeffrey G. Arnold Jimmy R. Williams James R. Kiniry Blackland Research Center Texas A&M AgriLife Research Temple Texas USA Grassland Research Center Agriculture Research Service United States Department of Agriculture Temple Texas USA

Water quality modeling requires across-scale support of combined digital soil elements and simulation parameters. This paper presents the unprecedented development of a large spatial scale (1:250,000) ArcGIS geodatabase coverage designed as a functional repository of soil-parameters for modeling and comparison of water quality outcomes in the United States. The set of target models include: SWAT (soil and Water Assessment Tool), APEX (Agricultural Policy Environmental Extender), and ALMANAC (Agricultural land management Alternatives with Numerical Assessment Criteria). This development relies on the Digital General soil Map (DGSM) as the source of soil information, and leverages on architectural design and associated tools created for a companion product at higher resolution from which also was extended a procedure for refilling a large number of missing derived parameters. Outlined by regional watershed layouts and supported by GIS land use layers, the core product is developed using the File Geodatabase (FGDB) data structure, which brings, via customized Python-based tools, the data directly into geoprocessing workflows. The FGDB implement efficiently stores spatial soil features, tabular model elements and linked relationships, while seamlessly providing the environment for the extraction, spatial analysis, and mapping of the models’ parameters. As an alternative, the composing spatial elements, polygons and multi-resolution rasters, and the models’ elements are offered as a file-folder system of data with completely Open Source formats. Finally, this geographic database coverage provides support for the traditional large-scale and harmonized application of the models as well as an alternative to the higher resolution companion for areas where this information is still under development.

关键词： Geodatabase soil SWAT APEX ALMANAC

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Mapping of Potential Groundwater Recharge Zones in the Kolleru Lake Catchment, India, by Using Remote Sensing and GIS Techniques

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Natural Resources 2020年第3期11卷 127-145页

作者： Meena Kumari Kolli Christian Opp Michael Groll department of Geography Philipps-Universit&aumlt Marburg Deutschhausstraße Marburg Hesse Germany Faculty of Geography Philipps-Universit&aumlt Marburg Deutschhausstraße Marburg Hesse Germany

Water scarcity is the major problem in India where the population has been tremendously increasing, which results in invading natural resources, thus affects on hydrological processes. Because of this, significant surface water bodies have been disappearing continuously. Therefore, more pressure on groundwater resources is a consequence of that. The integration of remote sensing and geographical information system (GIS), which helps in groundwater research for the investigation of potential groundwater availability, is essential to assess, monitor, and conserve groundwater resources. This analysis reports on the mapping of various potential groundwater resources in the Kolleru Lake catchment, India, by using remote sensing and GIS techniques. For this, a survey of India toposheets and IRC-1C satellite imageries was used to prepare thematic layers of geomorphology, drainage density, lineament, slope, land-use, soil, rainfall, and NDVI converted into raster format in ArcGIS. The raster maps of these thematic layers were assigned to a weight-based factor depending on the catchment characteristics and its topographic influence. The results demonstrated that about 7% of the area is under excellent groundwater potential recharge. Good, moderate, and lower potential conditions are 42%, 38%, and 13%, respectively. The results indicated that the management of groundwater potential zones should be targeted on the middle-catchment region. Further, the results were validated with the borehole data obtained from the Government of Andhra Pradesh-Groundwater department. These results are useful for better both planning and groundwater management sources in the Kolleru Lake catchment.

关键词： Groundwater Potential Zones Kolleru Lake Catchment India Remote Sensing GIS Weighted Overlay Analysis

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黄土高原关键带土壤水分空间分异特征

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地球与环境 2016年第4期44卷 391-397页

作者：王云强邵明安胡伟 Henry Lin 黄辉中国科学院地球环境研究所黄土与第四纪地质国家重点实验室西安710061 中国科学院地理科学与资源研究所生态系统网络观测与模拟重点实验室北京100101 New Zealand Institute for Plant&Food Research Limited Private Bag 4704Christchurch 8140New Zealand department of Ecosystem Science and management the Pennsylvania State UniversityUniversity ParkPA 16802USA 湖南师范大学资源与环境科学学院长沙410006

地球关键带是人类生存和发展的关键区域。关键带发生的一系列物理、化学和生物过程与人类活动密切相关。土壤水分是黄土高原关键带的关键要素,同时又是黄土高原植被恢复与生态环境重建的决定因子。为揭示黄土高原关键带土壤水分的空间... 详细信息

地球关键带是人类生存和发展的关键区域。关键带发生的一系列物理、化学和生物过程与人类活动密切相关。土壤水分是黄土高原关键带的关键要素,同时又是黄土高原植被恢复与生态环境重建的决定因子。为揭示黄土高原关键带土壤水分的空间分异特征,采用网格（50m×50m）布点,雨季结束后采集0~500cm深度土壤样品,结合室内分析,结果表明：黄土高原小流域中73个样点0~500cm的土壤含水量分布范围介于1%~23%之间,降水对0~100cm土层的土壤水分补充明显;土壤水分在水平和垂直方向都表现出明显的空间异质性,在不同方向上的水分控制过程有所不同,是对土地利用方式、植被类型、地形要素、土壤质地等多因素综合响应的结果。充分理解关键带土壤水分空间的分异规律及其主控因素有助于该区小流域综合治理中的植被建造与布局,也有助于对该区土壤水文和生物地球化学过程的理解。

关键词：黄土高原地球关键带土壤含水量土地利用空间变异性

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A framework for the use of decision-support tools at various spatial scales for the management of irrigated agriculture in West-Africa

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Agricultural sciences 2013年第8期4卷 9-15页

作者： Joost Wellens Farid Traoré Mamadou Diallo Bernard Tychon Association pour la Promotion de l’Education et de la Formation à l’Etranger (APEFE) Brussels Belgium Département sciences et Gestion de l’Environnement Université de Liège Arlon Belgium Institut de l’Environnement et de Recherche Agricole (INERA) Ouagadougou Burkina Faso Observatoire de l’Eau Bobo-Dioulasso Burkina Faso

The Kou watershed, situated in the Southwestern part of Burkina Faso, has succumbed since a couple of decades in a typical theater play of anarchistic water management. With its 1800 km2, this small watershed holds the second largest city of Burkina Faso (Bobo-Dioulasso), a former State ran irrigated rice scheme and several informal agricultural zones. Despite the abundance on water resources, most water users find themselves regularly facing to water shortages due to an increase in population and low irrigation efficiencies. Local stakeholders are hence in need of easy-to-use and low-cost decision support tools for the monitoring and exploitation of the water resources at different spatial and user levels. A top-to-bottom string of adapted water management tools has been successfully installed to tackle the problems: from watershed (top) to field level (bottom), passing by the 1200 ha irrigation scheme. land use maps have been derived from time-series of free satellite images. Combined with data from a network of hydrologic gauging stations, regional water use maps were established. SIMIS was put in place for the public-private management of the regions irrigated rice scheme. Day to day water use on irrigated plots was followed by soil humidity and crop canopy measurements. A simple field-cropwater balance model Aqua Crop was used by extension workers to draft optimal irrigation charts. Each tool was applied independently, requiring only limited data;but their combined results contributed to an improved integrated water management.

关键词： Irrigation Remote Sensing Multi-Level Decision-Support Tool

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Effects of different land use types on potential evapotranspiration in the Beijing-Tianjin-Hebei region, North China

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Journal of Geographical sciences 2019年第6期29卷 922-934页

作者： HAN Jingyan ZHAO Yong WANG Jianhua ZHANG Bing ZHU Yongnan JIANG Shan WANG Lizhen Institute of Hydrology and Water Resources Department of Hydraulic EngineeringTsinghua University State Key Laboratory of Simulation and Regulation of Water Cycle in River Basin China Institute of Water Resources and Hydropower Research Tianjin Key Laboratory of Water Resources and Environment Tianjin Normal University

Potential evapotranspiration(ET_0) is vital for hydrologic cycle and water resource assessments as well as crop water requirement and irrigation demand assessments. The Beijing-Tianjin-Hebei region(Jing-Jin-Ji)–an important, large, regional, economic community in China has experienced tremendous land use and land cover changes because of urbanisation and ecological restoration, affecting the hydrologic cycle and water resources of this region. Therefore, we analysed ET_0 in this region using climate data from 22 meteorological stations for the period 1991–2015 to understand this effect. Our findings show that ET_0 increased significantly at a rate of 7.40 mm per decade for the region. Based on the major land use type surrounding them, the meteorological stations were classified as urban, farmland, and natural stations using the 2015 land use dataset. The natural stations in the northern mountainous area showed a significant increase in ET_0, whereas most urban and farmland stations in the plain area showed a decrease in ET_0, with only a few of the stations showing an increase. Based on the different ET_0 trends for different land use types, these stations can be ranked as follows: urban stations(trend value:-4.663 to-1.439) > natural stations(trend value: 2.58 to 3.373) > farmland stations(trend value:-2.927 to-0.248). Our results indicate that land use changes affect meteorological parameters, such as wind speed and sunshine duration, which then lead to changes in ET_0. We noted that wind speed was the dominant parameter affecting ET_0 at all the natural stations, and wind speed and sunshine duration were the dominant parameters affecting ET_0 at most of the urban stations. However, the main controlling parameters affecting ET_0 at the farmland stations varied. These results present a scope for understanding land use impact on ET_0, which can then be applied to studies on sustainable land use planning and water resource management.

关键词： land use potential evapotranspiration meteorological parameters water resource management Jing-Jin-Ji region

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Preliminary Trial of Cover Cropping and Weed Control for Organic Rice

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American Journal of Plant sciences 2017年第11期8卷 2758-2768页

作者： Gena R. Mahato Anna McClung Sixte Ntamatungiro Surendra Singh Meghnath Pokharel Vince Wiley Bihu Huang department of Agriculture University of Arkansas at Pine Bluff Pine Bluff USA Dale Bumpers National Rice Research Center Stuttgart USA University of Tennessee Knoxville USA Kansas State University Manhattan USA

The experiment site at UAPB agronomy farm was left undisturbed for several years for organic rice experiment. soil samples taken in September 2015 showed that the experiment site was deficient with plant nutrients (NPK). Therefore, an organic fertilizer, Nature (8-5-5) was applied before planting mixture of crimson clover and winter wheat as cover crop in fall 2015. Biomass samples taken from the cover cropped land (CCL) and fallow land (FL) resulted in decrease in weed biomass by 33.36% and increase in total biomass by 46.78% in CCL than FL. Cover crops were incorporated one month before the rice sowing in June 2016. Fifteen rice cultivars were experimented for weed competition under water seeding cultivation method. Water seeding method was not effective to control the weeds as weeds dominated most of the rice plots since seedling stage. However, two rice cultivars namely Jasmine 85 and Rondo showed strong weed competition due to higher plant stand and better seedling establishment.

关键词： Organic Farming Water Seeding Flooding Plastic Mulch Covering Weed Pressure Varietal Selection Biomass

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