This paper describes a composed error model for estimating the conditional distribution of yield loss to serve as an insect damage function. The two-part error separates yield variability due to pest damage from other non-pest factors such as soil heterogeneity, non-uniform application of agronomic practices, and measurement errors. Various common functional forms (linear, quadratic, Cobb-Dougl...

Soil nutrient depletion is a major concern in terms of resource utilization and optimization of production in the middle hills of Nepal. Soil and nutrient losses from agricultural land is responsible for pollution of surface waters and this reduces the productive capacity of land. A field experiment was initiated in May 2001 on acidic sandy loam soil in Kavre district; Nepal to investigate the ...

The study and control of soil erosion and the associated environmental degradation is a difficult problem because it involves a very wide body of knOWledge. The use of knowledge based expert systems in this domain may improve the current efforts by providing an efficient tool for inter-disciplinary technology transfer and application. Domain expert systems may also be used as substitutes for hu...

Soil erosion and sedimentation processes can be considered as serious eco-environmentalproblems. This study aimed to estimate the basin-wide erosion using the Revised UniversalSoil Loss Equation (RUSLE). The soil erosion parameters included rainfall erosivity mapgenerated from the rainfall data, soil erodibility extracted from the soil map, land cover andmanagement map produced from supervised ...

suspended sediment resulted from distributed soil erosions facilitates nutrient transportation and influences soil depletion. phosphorus (p) is one of the major limiting nutrients controlling eutrophication of surface water. irregular p load pulsed by heavy rainfall may damage the ecological quality of downstream waters. p transport study during rainfall events is important in both predicting a...

in the universal soil loss equation (usle), soil erodibility factor (k) is estimated through nomograph. using the nomograph in calcareous soils may lead to uncertainty in estimating the erodibility factor. this study was conducted in hashtrud, (north west of iran) from march 2005 to march 2006. field measurements were carried out in an agricultural area of 30 km × 30 km. thirty six land grids w...

The revised universal soil loss equation (RUSLE), the sediment delivery distributed (SEDD) model, and ArcView GIS were used to estimate the impacts of no-till practice on soil erosion and sediment yield in Pataha Creek Watershed, a typical dryland agricultural watershed in southeastern Washington. The results showed that the average cell soil loss decreased from 11.09 to 3.10 t/ha yr for the wh...

The Loess Plateau lies in the North of China and is one of the most serious regions of soil erosion in the world. Severe loss of soil and water not only has its devastating effect on farming, forestry, stock-breeding and ecological environment of the area concerned, but also is the root of poverty for local people. The Loess Plateau has a long cultivation history, hence population growth, veget...

Bioremediation is an effective measure in dealing with such contamination, particularly those from petroleum hydrocarbon sources. The effect of soil amendments on diesel fuel degradation in soil was studied. Diesel fuel was introduced into the soil at the concentration of 5 % (w/w) and mixed with three different organic wastes tea leaf, soy cake, and potato skin, for a period of 3 months. Withi...