Browse on keywords: organic matter fertilizer
Search results on 05/24/13
1077. Broadbent, F.E. and F.J. Stevenson. 1966. Organic matter interactions.. Agricultural anhydrous ammonia: technology and use. p. 169-197..
3210. Bhatti, A.U.. 1990. Spatial variability and geostatistical estimation of soil properties and wheat yield on eroded lands in the Palouse region.. Chpt. 3, PhD. Dissertation, Dept. of Agronomy & Soils, Washington State Univ., Pullman, WA 99164.
Spatial variability of organic matter, soil P, and wheat yields was studied using classical statistical and geostatistical approaches on two commercial wheat farms in the Palouse region of eastern Washington. Geostatistics indicated strong spatial relationship of soil properties and wheat yields with a range of influence of 50-200 m. The two sites differed greatly in spatial patterns due primarily to differences in topography and the extent of erosion and topsoil loss. As a consequence of topsoil loss and reductions in organic matter, it was demonstrated that spatial patterns in yield and soil phosphorus were strongly correlated with organic matter patterns. Remote sensing of soil organic matter and the use of geostatistics offers a way to quickly assess spatial patterns in grain yield and available phosphorus.
6572. Smith, V.T., L.C. Wheeting, and S.C. Vandecaveye. 1946. Effects of organic residues and nitrogen fertilizers on a semiarid soil.. Soil Science 61:393-410.
Determined the effect of wheat straw, manure, and N fertilizer on soil organic matter, N supply of the soil, and yield and protein of wheat, over 18 years. Manure N was equal to treatment with 1600 lb/ac straw and 100 lb/ac ammonium sulfate. No treatment greatly changed wheat yield or test weight. The N content of grain increased with manure, ammonium sulfate alone, and straw plus ammonium sulfate. All treatments increased organic C except 100 lb/ac ammonium sulfate alone, and 50 lb/ac ammonium sulfate plus 800 lb/ac straw, and the check. All plots but 2 lost N during the experiment. The C/N ratio increased in every plot regardless of treatment.
10166. Anon.. 1991. Sludge fertilizers get new life from waste crisis.. Agrichemical Age, March, 1991 p. 46..
With little or no new land available for expanding existing landfills, cities, counties and industries are turning to recycling as an alternative to waste sludge disposal. Treated sewage sludge is now being used as a natural soil amendment. To be eligible for recycling, all sludge must be treated and stabilized to kill any pathogens and to eliminate odors. Treated sludge provides a good source of nutrients to the soil. To the farmer, treated sludge represents an inexpensive source of nitrogen and organic matter which reduces the need for manufactured fertilizers. The EPA supports and promotes recycling of municipal waste and has set guidelines regulating its treatment and use.
10225. Rasmussen, P.E. and H.P. Collins. 1991. Long-term impacts of tillage, fertilizer, and crop residue on soil organic matter in temperate semi-arid regions.. Advances Agronomy 45:93-134.
Organic matter is an important soil component in semi-arid regions. Virgin grassland soils lose organic matter rapidly upon first cultivation, with the greatest decline in the first 10-20 years. A new equilibrium is usually established after 50-60 years. Long-term experiments or paired comparisons are needed to evaluate change in organic matter due to managment. Organic matter loss is greater with increasing frequency of fallow and intensity of tillage. Conservation tillage generally increases organic matter, and results from studies worldwide are presented. N fertilizer generally leads to higher organic matter, since it boosts biomass production. About 18% of the applied N at Pendleton was incorporated into the organic fraction in a wheat-fallow system. Amount of crop residue influences organic matter levels far more than type of residue. Organic matter increases linearly with increasing residue additions. Semi-arid soils can sequester from 10-25% of the C added. Many agricultural soils are not receiving sufficient C additions to prevent continued organic matter loss under current management.