Alfalfa is a good green manure source, but its effect on rice growth has not been fully elucidated. Two green manure species, alfalfa and broad bean (Vicia faba L.), and two N fertilizer levels, alone or combination, were applied to a rice field. The results indicated that alfalfa had more pronounced effects on increasing soil labile phosphorus (P) fractions (including NaHCO3-Pi, NaOH-Pi), P up...

Data from 139 research sites throughout the Inland Northwest were analyzed for effects of ash cap on site productivity, nutrient availability and fertilization response. Stand productivity and nitrogen (N) fertilizer response were greater on sites with ash cap than on sites without. Where ash was present, depth of ash had no effect on site productivity or N fertilizer response. Site productivit...

In this study, poultry manure compost and organic fertilizer were added to soils derived from basalt, granite, and river alluvial deposits for use as soil parent materials. Following incubation periods of 30 or 60 days at 25 °C, the physical and chemical properties and adsorption characteristics of the soils were studied. The results indicated that the application of poultry manure compost or o...

A highly effective biological fertilizer (bio-fertilizer) can be produced cheaply in countries that have a source of a suitable type of zeolitic rock (tuff). Such rocks occur worldwide in areas of past or current volcanism. In the event of explosive volcanic activity huge volumes of silicic glass and other debris are projected into the atmosphere. Reaching high altitude the fine material is sep...

The prospect of using wastewater containing high loads of soluble organic matter (OM) for removing residual agricultural chemicals (fertilizer, pesticide, or herbicide) in farm soil, although promising, could have adverse effects on soil agricultural quality as a result of development of redoximorphic features in the soil profile. In this study, the effect of organic carbon supplement for biore...

Global gridded crop models (GGCMs) are increasingly used for agro-environmental assessments and estimates of climate change impacts on food production. Recently, the influence of climate data and weather variability on GGCM outcomes has come under detailed scrutiny, unlike the influence of soil data. Here we compare yield variability caused by the soil type selected for GGCM simulations to weat...

Soil microbial communities under three agricultural management systems (conventionally tilled cropland, hayed pasture, and grazed pasture) and two fertilizer systems (inorganic fertilizer and poultry litter) were compared to that of a w150-y-old forest near Watkinsville, Georgia. Both 16S rRNA gene clone libraries and phospholipid fatty acid (PLFA) analyses indicated that the structure and comp...

BACKGROUND: While recognizing the economic obstacles that currently block widespread use, many concerned with improving agricultural productivity and food security in Sub-Saharan Africa (SSA) are focusing on fertilizer as a remedy for declining soil quality and stagnant yields. Some have suggested that SSA needs to increase fertilizer use from 9 to at least 30 kg/ha during the next decade. Othe...

In South Africa during the past four decades considerable research has taken place on the nutrient requirements of sugarcane. Consequently marked changes have occurred in patterns of fertilizer use. The value of N, P and K fertil~zers for cane production is reviewed using field experimental data. Correlations established between soil and leaf analysis and crop responses to various nutrients are...

Rice (Oryza sativa L.) grown on a clay soil in a direct-seeded, delayed-flood system as used in the southern U.S. requires 30 to 60 lb/acre more nitrogen (N) fertilizer to achieve maximal grain yields compared to rice grown on silt loam soils. Seasonal N fertilizer accumulation studies are almost non-existent for rice grown on clay soils. Therefore, a two-year field study was conducted to evalu...