نتایج جستجو برای: soil drainage 0028
تعداد نتایج: 219466 فیلتر نتایج به سال:
abstract by increasing the world population and more need to supply food, farmers attend to use of chemical fertilizers, organic manures and pesticides. also, applications of these agents without attention to their side effects, cause more problems to human health and environment. nitrate is one of the most important elements of organic manures, which leach through soil to surface and ground wa...
Soil saturated hydraulic conductivity (k) and effective porosity (f) are the most important parameters to simulate the processes associated with irrigation, drainage, hydrology, leaching and other agricultural and hydrological processes. Present methods to measure these parameters are often difficult, time consuming and costly. Therefore, a method which provides more accurate estimates of these...
Plant salt stress is a condition where excessive salts in soil solution cause inhibition of plant growth or plant death. On a world scale, no toxic substance restricts plant growth more than does salt. Salt stress presents an increasing threat to plant agriculture. Among the various sources of soil salinity, irrigation combined with poor drainage is the most serious, because it represents losse...
Tom Scherer Extension Agricultural Engineer The presence of salts and high water tables in North Dakota soils due to an extended climactic wet cycle recently has stimulated interest in the installation of tile drainage systems. The tile controls the water table and encourages the leaching and removal of salts from the soil above the tile lines. This improves soil productivity, culminating in im...
Nonpoint source contamination of surface and groundwater resources with nitrate-N (NO3-N) has been linked to agriculture across the midwestern USA. A 4-yr study was conducted to assess the extent of NO3-N leaching in a central Iowa field. Water flow rate was monitored continuously and data were stored on an internal datalogger. Water samples for chemical analysis were collected weekly provided ...
Many hydrological studies of forested ecosystems focus on the study of the forest canopy and have partitioned gross precipitation into throughfall and stemflow. However, the presence of forest litter can alter the quantities of water available for soil infiltration and runoff. Little information exists regarding the value of storage and drainage parameters for litter layers. Vegetation paramete...
Countermeasures to urban flooding should consider long-term perspectives, because climate change impacts are unpredictable and complex. Urban green spaces have emerged as a potential option to reduce urban flood risks, and their effectiveness has been highlighted in notable urban water management studies. In this study, flooded areas in Seoul, Korea, were divided into four flooded area types by...
Despite the use of best management practices for nitrogen (N) application rate and timing, significant losses of nitrate nitrogen (NO3(-)-N) in drainage discharge continue to occur from row crop cropping systems. Our objective was to determine whether a autumn-seeded winter rye (Secale cereale L.) cover crop following corn (Zea mays L.) would reduce NO3(-)-N losses through subsurface tile drain...
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