The present study investigates the concentration of Pb, Cd, Ni, Zn, and Cu in the paddy field soils collected from Tumpat, Kelantan. Soil samples were treated with sequential extraction to distinguish the anthropogenic and lithogenic origin of Pb, Cd, Ni, Zn, and Cu. ELFE and oxidizable-organic fractions were detected as the lowest accumulation of Pb, Cd, Ni, Zn, and Cu. Therefore, all the heav...

the prevalent method of irrigation in paddy fields in iran is continuous ponding, which changes to intermittent method at the time of water shortage. soil cracks are the main problem in intermittent irrigation. in this study, effects of adding rice straw on some soil physical characteristics and cracks were studied in paddy soils of the guilan province of iran. the experiment was performed as s...

A comprehensive biogeochemistry model, DNDC, was revised to simulate crop growth and soil processes more explicitly and improve its ability to estimate methane (CH4) emission from rice paddy fields under a wide range of climatic and agronomic conditions. The revised model simulates rice growth by tracking photosynthesis, respiration, C allocation, tillering, and release of organic C and O2 from...

The effect of moderate UV-irradiation (45J/m2) on species diversity of asporogenic heterotrophic bacterial isolates from paddy field soil was studied. Although the isolates from irradiated Petri dishes had less pronounced hydrolytic abilities and eutrophs were less numerous, irradiation did not result in specific selection of UV-resistant bacteria. Species diversity indices were higher for the ...

The accumulation of As in rice due to groundwater irrigation in paddy fields represents a serious health hazard in South and Southeast Asia. In Taiwan, the fate of As in long-term irrigated paddy fields is poorly understood. Groundwater, surface soil, and rice samples were collected from a paddy field that was irrigated with As-containing groundwater in southwestern Taiwan. The purpose of this ...

Arsenic (As) levels in drinking water and in irrigation water used for rice paddies can exceed the World Health Organisation (WHO) drinking water quality limit of 0.05 mg L across many regions in South East Asia. This is due to the dissolution of As-rich minerals in the groundwater hosting bedrock. In polluted groundwater, concentrations can exceed water quality limits to a factor of 900, reach...

The present study focused on isolation and characterization of Azospirillum sp. from paddy field soils of Thanjavur (Dt), Tamil Nadu. The physico-chemical characteristics of the soil samples were analysed by using standard methods. Totally nine native strains of Azospirillum were isolated. Among the nine isolated strains three strains were belonging to Azospirillum amazonense and six strains be...

This study aimed at the development of method of monitoring paddy rice planting applicable to areas located in the tropical humid climate region. The method was integrated with two steps of procedure. As the first step, we attempted to produce land use map which discriminated paddy field using multi-temporal Landsat data. In order to remove the effect of cloud cover, a new method of land use cl...