cadmium is one of the most toxic pollutants in the surface soil layer the accumulation of which in soils as well as in crops is of increasing concern. in addition, zinc is a micronutrient in rice nutrition which is in interaction with cd. a pot experiment was carried out to study the effects of zinc and cadmium on rice growth and as well on concentrations of zn, cd, fe and mn in soil. a factori...

This study was made in an effort to learn why saturating the soil with water causes almost immediate injury or death of many species of plants. While it has been shown that the deficient aeration accompanying flooding' injures or kills the root systems, this fact does not explain why the shoots are injured so quickly. Injury is usually attributed to desiccation, caused by decreased water absorp...

The behavior of As in paddy fields is of great interest considering high As contents of groundwater in several Asian countries where rice is the main staple. We determined the concentrations of Fe, Mn, and As in soil, soil water, and groundwater samples collected at different depths down to 2 m in an experimental paddy field in Japan during the cycle of flooded and non-flooded periods. In addit...

This study investigates percolation and seepage through the bunds of flat and terraced paddies. Field experiments were conducted in Hsin-Pu of Hsin-Chu County, Taiwan, to measure the soil water content of various types of bund. Measurements revealed that the soil was unsaturated along the sloped surface of the terrace. Experimental results also indicated that seepage face flow did not develop e...

We investigated the effects of the water status (flooded or non-flooded) and presence of the nosZ gene in bradyrhizobia on the bradyrhizobial community structure in a factorial experiment that examined three temperature levels (20°C, 25°C, and 30°C) and two soil types (andosol and gray lowland soil) using microcosm incubations. All microcosms were inoculated with Bradyrhizobium japonicum USDA6T...

We studied the resident (16S rDNA) and the active (16S rRNA) members of soil archaeal and bacterial communities during rice plant development by sampling three growth stages (vegetative, reproductive and maturity) under field conditions. Additionally, the microbial community was investigated in two non-flooded fields (unplanted, cultivated with upland maize) in order to monitor the reaction of ...

The effects of flooding harvested rice fields on waterbird communities were studied during winter. Variation in the number of waterbird species, overall densities of all waterbirds, wading birds, waterfowl, and shorebirds, and a measure of conservation value that weighted species according to their relative abundance and population trends were examined. Each variable was tested for differences ...

Arsenic (As) exposure from consumption of rice can be substantial, particularly for the population on a subsistence rice diet in South Asia. Paddy rice has a much enhanced As accumulation compared with other cereal crops, and practical measures are urgently needed to decrease As transfer from soil to grain. We investigated the dynamics of As speciation in the soil solution under both flooded an...

During 2012–13, the presence of ascomycetous species in soil was studied in Kermanshah province (W Iran). In each location, samples were collected from 0–30 cm depth and passed through 2 mm, 40 and 60 mesh sieves. Using soil plating method, 10 g of soil samples were placed in 90 ml of 0.1% water-agar containing 100 ppm NPX, mixed and serially diluted to 10-2 to 10-5 and 1 ml of each solution fl...