Root biomass distributions have long been used to infer patterns of resource uptake. These patterns are used to understand plant growth, plant coexistence and water budgets. Root biomass, however, may be a poor indicator of resource uptake because large roots typically do not absorb water, fine roots do not absorb water from dry soils and roots of different species can be difficult to different...

Different techniques for estimating seasonal water use from soil profile water depletion frequently do not account for flux below the root zone. Shallow water table contribution to supply crop water use may be important in arid and semi-arid regions. Development of predictive root uptake models, under influence of shallow water table makes it possible for planners to incorporate interaction bet...

The behavior of turfgrass-infesting scarab grubs in response to soil physical properties may affect the stress that each species exerts on turfgrass and the efficacy of control tactics. To gain a more realistic picture of the events that occur within the soil matrix, we have developed a nondestructive X-ray technique to study soil insect movement and behavior in simulated and natural soil block...

The use of pesticides in modern agriculture is unavoidable because they are required to control weeds. Pesticides are poisonous; hence, they are dangerous if misused. Understanding the fate of pesticides will be useful to use them safely. Therefore, contaminations of water and soil resources could be avoided. The fates of pesticides in soils are influenced by their sorption, decomposition and m...

The Serra do Mar complex in the southeastern Brazil is subject to frequent landslides especially on the Atlantic coast. The three dimensional organisation of the soil was studied in a 56 ha representative catchment. Upslope in situ soil material has developed from the parent rock, and downslope the soil has resulted from landslide processes. The soil mantle upslope is mainly characterised by sl...

Testing of pesticide leaching models against comprehensive field-scale measurements is necessary to increase confidence in their predictive ability when used as regulatory tools. Version 5.1 of the MACRO model was tested against measurements of water flow and the behaviour of bromide, bentazone [3-isopropyl-1H-2,1,3-benzothiadiazin-4(3H)-one-2,2-dioxide] and imidacloprid [1-(6-chloro-3-pyridylm...

A model of unsaturated soil-water movement using a prediction model of basic physical soil properties for calculating correlation functions was developed using VADOSE/W. The reliability of the model was assessed by comparing the results with those of a soil-column test. Coefficients of determination, R2, between the simulated and the measured daily evaporation for sand-mulch thicknesses of 0 (c...

:Picloram (4.amino-3,5,6-trichloropicolinic acid) is a ‘herbicide used for the control of woody and broadileaf plants and is marketed by the Dow Chemical .Companyi in formulations bearing the trade name Tordon@. Many agriculturally-impel-tant broadleaf ‘crops are susceptible lo very low levels of pi&ram lI@ab 1975: Thomson 1978). The potassium salt of picloram is very soluble in water and is sl...

The water budget in clay shale terrain is controlled by a complex interaction between the vertisol soil layer, the underlying fractured rock, land use, topography, and seasonal trends in rainfall and evapotranspiration. Rainfall, runoff, lateral flow, soil moisture, and groundwater levels were monitored over an annual recharge cycle. Four phases of soil–aquifer response were noted over the stud...

A laboratory experiment was conducted by using three herbicides, two from dinitroaniline group and one from thiocarbamate group to know their degree of downward movement (leachability) through soil columns and their contribution in ground water contamination. Soil columns were loaded with Pendimethalin, Benthiocarb and Oryzalin at doses of 10.0, 10.0 and 7.7 kg/ha, respectively. After 30 days s...