搜索结果: 1-15 共查到“农业工程 water”相关记录58条 . 查询时间(0.187 秒)
Fallowing cattle-feed farmland simplest way to alleviate western water shortages（图）
Fallowing cattle-feed farmland simplest western water shortages
2020/3/6
The rate at which humans consume fresh water is now approaching or surpassing the rate at which water sources are naturally replenished, creating shortages for people and ecosystems.In the western U.S...
Survey of soil water distribution in a vineyard and implications for subsurface drip irrigation control
gravimetric water content Sentek Diviner spatio-temporal variability volumetric water content
2016/8/2
Controlling a subsurface drip irrigation system based on soil water monitoring is a very efficient way to supply grapevines with water for optimal thriving and high vintage quality. However, finding a...
Evaluations of the effects of soil properties and electrical conductivity on the water content reflectometer calibration for landfill cover soils
soil electrical conductivity soil index properties time domain reflectometry volumetric water content WCR calibration
2016/8/2
This study presents soil-moisture calibrations using low-frequency (15–40 MHz) time domain reflectometry (TDR) probe, referred to as water content reflectometer (WCR), for measuring the volumetric wat...
Application of historical and recent aerial imagery in monitoring water erosion occurrences in Czech highlands
Atlas EROZE model erosion modelling land-use changes remote sensing soil erosion
2016/8/2
This study is focused on the historical evolution of a heavily eroded field with discontinuous grass cover on a major thalweg (ephemeral gully). Tens of parcels originally formed a protective pattern ...
Estimation of the soil water retention curve (SWRC) using pedotransfer functions
continuous pedotransfer function soil water retention curve fitting parametric method neural network
2015/1/30
Soil hydraulic characteristics, especially the soil water retention curve and hydraulic conductivity, are essential for many agricultural, environmental, and engineering applications. Their measuremen...
Difference in Canopy and Air Temperature as an Indicator of Grassland Water Stress
water stress indicator air temperature canopy temperature soil moisture grassland vapour pressure deficit actual evapotranspiration
2015/1/28
In 2003–2005 in conditions of the moderately warm region of the Třeboň Basin (Czech Republic) the difference between canopy temperature (Tc) and air temperature at 2 m (Ta) was tested as an indic...
A Site-sPecific Agricultural water Requirement and footprint Estimator (SPARE:WATER 1.0)
ite-sPecifi c Agricultural water footprint Estimator
2014/12/12
The agricultural water footprint addresses the
quantification of water consumption in agriculture, whereby
three types of water to grow crops are considered, namely
green water (consumed rain...
世界水土保持协会（World Association of Soil and Water Conservation，WASWAC)
世界水土保持协会 World Association of Soil and Water Conservation WASWAC
2013/8/6
World Association of Soil and Water Conservation (WASWAC), as a worldwide academic society, was established in USA in August 1983. The secretariat of WASWAC was initially at the Soil and Water Conserv...
Silage-corn harvesting machinery traffi c eff ects on soil bulk density and water permeability
repeated traffi c passes silage harvester soil compaction soil physical damage soil porosity
2014/2/24
Soil compaction caused by machinery traffi c aff ects the growth of agricultural crops and also has environmental eff ects
like soil damage and erosion. Field experiments were cond...
USE OF EARTH OBSERVATION FOR GEOSPATIAL CROP WATER ACCOUNTING OF RAIN-FED AGRO-ECOSYSTEM IN INDIA
Earth observation seasonal phenology WRSI rain-fed agro-ecosystem crop yield
2014/5/6
Use of earth observation by means of remote sensing and in-situ meteorological network in integrated manner have improved ability to track water availability and associated yield reduction in rain-fed...
柴油机富氧进气燃用乳化柴油的循环变动与燃烧特性（Cycle-by-cycle Variations of a DI Engine Fueled with Water Emulsion Diesel and Oxygen Enriched Intake Air）
直喷柴油机 富氧进气 富氧燃烧 水乳化柴油
2010/12/29
在直喷柴油机上采用进气增氧（氧气在进气中的体积分数为21%、23%、25%和30%）技术，对燃用不同掺水比乳化柴油（水在乳化柴油中的体积分数为0％、10％、20％和30％）的循环变动及燃烧特性进行研究；实验工况为发动机经济转速、中等负荷，采集20个连续循环，取最大爆发压力值，计算循环变动率。研究结果表明：在纯柴油条件下，随氧含量的增加，缸内最大爆发压力增加，循环变动率降低，燃烧始点提前；在使用乳化...
长距离输水系统停泵水锤的数值模拟（Numerical Simulation of the Water Hammer Caused by Accidental Pump-stop in Long Water Supply Systems）
泵站 供水工程 水力计算 水锤压力
2010/12/29
运用瞬态水力学理论和特征线方法，结合某实际工程，对联合采用空气阀、泄压阀和二阶段缓闭蝶阀进行水锤防护的长距离有压输水管道系统的事故停泵水力过渡过程进行了计算和分析，得到管线沿程的水锤压力包络线和空化体积曲线，以及典型断面的压力时程线。计算结果表明，采用两阶段缓闭蝶阀、泄压阀和空气阀进行水锤安全防护是十分必要的，有利于抑制正水锤压力的继续升高和阻止负水锤压力的持续降低，防止断流弥合水锤的发生。但从计...
淡水与微咸水入渗特性对比分析（Infiltration Characteristic Contrast Analysis of Fresh Water and Saline Water）
微咸水 淡水 间歇入渗 连续入渗
2010/12/29
为了研究淡水与微咸水连续和间歇入渗特性的差异，采用矿化度1.33g/L的淡水与矿化度3g/L的微咸水，在黏质土壤条件下进行了一维积水连续入渗及间歇入渗试验。研究结果表明，采用微咸水入渗可以改变土壤的结构特性，从而增大土壤的入渗能力；利用一维代数入渗模型对试验资料进行处理，结果表明模型可以比较精确地描述微咸水入渗过程；入渗水为淡水时，间歇入渗减渗，而入渗水为微咸水时，间歇入渗增渗；间歇入渗的循环...
不同初始含水率条件下的微咸水入渗实验（Saline Water Infiltration with Different Initial Moisture Contents）
微咸水 初始含水率 累积入渗量 湿润锋
2010/12/29
针对矿化度均为3g/L的微咸水入渗时，土壤初始含水率对土壤入渗过程的影响，采用室内均匀土柱一维垂直入渗实验方法，分别对初始含水率为2.25%、8.18%、13.12%、16.40%的土柱入渗过程进行了研究。分析了不同土壤初始含水率对累积入渗量和湿润锋推进深度以及土柱剖面含水率的影响。采用Kostiakov模型对累积入渗量和时间的关系进行了拟合，结果表明累积入渗量与初始含水率呈负相关关系。采用幂函...
不同种植模式麦田水资源利用率及边际效益分析（Effects of Different Planting Patterns on Water Use Efficiency and Marginal Profits of Winter Wheat）
冬小麦 种植模式 水资源利用率
2010/12/29
选用山东省当前推广面积较大的“20+40”大小行、“20+40”沟播、“20+40”垄作以及常规等行距模式，研究不同种植模式对冬小麦农田水资源利用效率和边际效益的影响。结果表明，等行距、大小行、沟播和垄作种植模式的最大产量分别为7778.6、7624.8、8684.6和8893.7kg/hm2，表明沟播和垄作都具有提高冬小麦产量的潜力，但在获得最大产量时，垄作的蒸散量比沟播提高了76.6mm。...