This study was conducted to determine if the Agricultural Policy/Environmental Extender (APEX) model could reasonably replicate the effects of silvicultural practices on streamflow and loading of sediments and nutrients. APEX was modified to enhance factors associated with forestry conditions such as rainfall interception by canopy, litter, subsurface flow, nutrient movement, and routing enrich...

Phosphorus is an essential plant nutrient and critical to agricultural production, but it is also a problem when excessive amounts enter surface waters. Summer rotational grazing and winter feeding beef pasture systems at two fertility levels (56 and 28 kg available P ha) were studied to evaluate the P losses from these systems via surface runoff and subsurface flow using eight small (0.3–1.1 h...

Fluidized gas desulfurization gypsum is a popular agricultural soil amendment used to increase calcium and sulfur contents, and reduce aluminum toxicity. Due to its surface application in conservation tillage systems and high solubility, the soluble components of gypsum may be transferred with agricultural runoff into receiving waters. The current study measured toxicity of gypsum to Ceriodaphn...

The relationship between STP (soil test P) and DRP (dissolved reactive P) in runoff has been shown to vary with soil type due to differences in soil properties. The purpose of this study was to determine if soil tests could indirectly take into account differences in soil properties and thus provide one relationship with STP and runoff DRP among a variety of soil types. Nine different soil type...

Fish and other organisms are affected by pesticides which pollute the natural water through agricultural runoff. The aim of this study was to determine the acute toxicity of botanical pesticide, neem gold, and two synthetic pesticides, permethrin and monocrotophos, which are extensively used in agricultural farms. The mortality rate of Cyprinus carpio was monitored under laboratory conditions f...

Midwest by converting upland and wetland habitats to crops and pastures, simultaneously changing hydrologic conditions and water quality, and threatening the region’s biodiversity (Table 1). Where corn is the dominant crop (in Iowa, Illinois, and Indiana, in particular), extensive networks of perforated pipes and drainage ditches were installed to drain wetlands. As a result, surface and ground...