Oxygen and carbon isotopic compositions of ambient carbon dioxide in two tropical forests in the Amazonian basin were determined at the beginning and the end of the dry season. One site, Fazenda Vitoria, is typical of a seasonal forest with a pronounced dry season from May to November whereas the other site, Reserva Ducke, has a milder dry season. Samples collected at night revealed that in the...

The nutrient status of grazing beef cattle from four selected soil order regions of Florida was examined. Liver, blood, hair and feces samples from 14 heifers and 14 cows, plus forage samples, were collected during two periods of the year from nine ranches located in four different regions. Soil samples were collected during one period. The soil order regions were the Histosol (southeast), Spod...

Laboratory experiments were conducted by applying 1,2-dibromo-3-chloropropane (DBCP) to sealed vials of soil infested with Meloidogyne javanica. A minimum initial concentration of 0.25 mug of DBCP/g of oven-dry soil killed all nematodes within 35 days. A concentration of 1.0 mug/g killed all nematodes within 28 days. The rate of degradation of this chemical was determined by treatment of steame...

In this study, to remove the effects of topography and surface roughness to observed spectrum initially, a method using the normalised reflectance (pseudoreflectance) was employed. Then, we examined the removal of the vegetation effects (such as green vegetation and dry vegetation) and a method to estimate soil pseudo-reflectance spectrum, because the ground surface shows the mixture of soil an...

The weather patterns of the west side of the Sierra Nevada Mountains (cold, wet winters and hot, dry summers) strongly influence how water is partitioned between transpiration and evaporation and result in a specific strategy of water use by ponderosa pine trees (Pinus ponderosa) in this region. To investigate how year-round water fluxes were partitioned in a young ponderosa pine ecosystem in t...

The water balance equation dictates that streamflow may be reduced by transpiration. Yet temporal disequilibrium weakens the relationship between transpiration and streamflow in many cases where inputs and outputs are unbalanced. We address two critical knowledge barriers in ecohydrology with respect to time, scale dependence and lags. Study objectives were to correlate components of the water ...

Phytoextraction is gaining acceptance as a cost-effective and environmentally friendly phytoremediation strategy for reducing toxic metal levels from contaminated soils. Cognizant of the potential of this phytoremediation technique as an alternative to expensive engineering-based remediation technologies, experiments were conducted to evaluate the suitability of some plants as phytoextraction s...

background & aim: in order study the effect of thiobacillus, sulphur and organic materials on vegetative growth and essence production in lemon balm (melissa officinalis l.) was conducted in pots in field condition at shahrekord, iran on 2008. experimental: the factors were ten soil treatments inclusive 200 kg/ha sulphur, 400 kg/ha sulphur, 600 kg/ha sulphur, 200 kg/ha sulphur + thiobacill...