Simple nitrogen (N) input/output balance calculations in agricultural systems are used to evaluate performance of nutrient management; however, they generally rely on extensive assumptions that do not consider leaching, denitrification, or annual depletion of soil N. We constructed a relatively complete N mass balance for the Big Ditch watershed, an extensively tile-drained agricultural watersh...

The accumulation of a trace metal in rice grain is not only affected by the total concentration of the soil trace metal, but also by crop variety and related soil properties, such as soil pH, soil organic matter (SOM) and so on. However, these factors were seldom considered in previous studies on mapping the pollution risk of trace metals in paddy soil at a regional scale. In this study, the sp...

  Crop yields are dependent on a number of factors such as soil type, weather conditions and farming practices. Crop yield estimates in different soil types are required to meet the needs of farmers, land appraisers, and governmental agencies in Iran as around the world. This study was conducted to model the wheat-grain yields [Triticum aestivum L.]  by soil properties in Khoy area, the north-w...

this experiment was conducted in order to study the influence of different levels of municipal solid waste compost and nitrogen rate on grain quality of sweet corn (zea mays l. saccharata) and some soil properties under marvdasht conditions during growing season of 2008-2009. the experiment was arranged as split plots based on a randomized complete block design with two factors and three replic...

This paper presents the effect of geogrid tensile strength by calculating pullout resistance and geogrid-soil interaction mechanism. In order to investigate this interface, a series of pullout tests have been conducted by large scale reformed direct shear test apparatus in both cohesive and granular soils. In numerical, finite difference software FLAC3D has been carried out on experimental test...

Large-scale simulation of the soil-derived dust emission in semi-arid regions needs to account for the in ̄uence of the soil moisture on the wind erosion threshold. Soil water retention consists of molecular adsorption on the soil grain surface and capillary forces between the grain. Interparticle capillary forces (characterized by the moisture tension) are the main factor responsible for the in...

Introduction: Ice grain size controls the geodynamic evolution of the ice I shells of large to mid-sized icy satellites. Grain size controls the viscosity of ice [1,2], and thus, the heat flux from the outer ice I shell by controlling the likelihood and efficiency of convection. In addition, the rheology of ice controls the depth to the brittle/ductile transition, which is a key control on endo...

Present production of rice is far below its reported potential yield because of being Ndeficiency, the major constraint. Because of poverty, small farmers have to rely on native soil N-supply. Between wheat harvest and rice transplanting, a dry-to-wet season transition (DWT) period exist with changing soil moisture from aerobic to anaerobic and a large amount of native soil N loss is hypothesiz...