abstract land use change, especially natural ecosystems transformation, has high effects on soil physico-chemical as well as biological characteristics and also, has effect on runoff and soil erosion. analysis of runoff and soil erosion dynamics can be useful in improvement of management proposals and quantifying runoff and soil erosion changes. so, this research was carried out to investigate ...

Runoff P associated with eroded soil is partly solubilized in receiving waters and contributes to eutrophication, but the significance of particulate phosphorus (PP) in the eutrophying P load is debatable. We assessed losses of bioavailable P fractions in field runoff from fine-textured soils (Cryaquepts). Surface runoff at four sites and drain-flow at two of them was sampled. In addition to di...

In recent years growing human pressure on agricultural land in the north of the Lao PDR has led to accelerated degradation processes along hillslopes, and higher sediment delivery rates to streams. Furthermore, high demand from urban centres is attracting farmers to cultivate vegetables in riparian areas. These land-use changes may have negative affects on stream water quality. The aims of this...

We investigated the mechanisms leading to rapid death of corals when exposed to runoff and resuspended sediments, postulating that the killing was microbially mediated. Microsensor measurements were conducted in mesocosm experiments and in naturally accumulated sediment on corals. In organic-rich, but not in organic-poor sediment, pH and oxygen started to decrease as soon as the sediment accumu...

The Annualized Agricultural Non-Point Source (AnnAGNPS) model has been developed to quantify watershed response to agricultural management practices. The objective of this study was to identify critical areas where conservation practices could be implemented and to predict their impact on Beasley Lake water quality in the Mississippi Delta using AnnAGNPS. Model evaluation was first performed by...

Taking the two typical tributaries in the loess plateau as an example, the hydrological effects of water and soil conservation measures were studied with parallel comparative analysis method. The results show that water and soil conservation measures can reduce annual runoff and sediment module, cut down flood peak discharge and lower sediment concentration efficiently. And meanwhile, it also c...