نتایج جستجو برای: organic low input production
تعداد نتایج: 2080527 فیلتر نتایج به سال:
Temporal variations in soil microbial biomass C concentration and in activity of extracellular enzymes of the cellulolytic complex were investigated in a ®eld experiment after eight years of cultivation with either low organic matter input (low-OM) or high organic matter input (high-OM). The cultivation systems differed in whether their source of fertiliser was mainly mineral or organic, in whe...
The forms and dynamics of soil phosphorus can be greatly affected by land use changes, which often involve changes in vegetation cover, biomass production and nutrient cycling in the ecosystem. Present research evaluates the impact of land use change on the amount of total organic and inorganic P, labile, moderately labile and nonlabile P pools in semiarid soils of central Zagros. Samples were ...
the objectives of this study was to estimation of greenhouse gases (ghg) emissions and global warming in rice production and identify measures to reducing fossil energy use and greenhouse gases emissions. three rice production systems included sri, improved and conventional were studied. all activities, field operation and data in production methods and differents inputs rates were monitored an...
Improving nitrogen (N) use efficiency in crop production is important for obvious economic and environmental reasons. Nitrogen fertilization of corn usually provides the greatest return on investment of any crop input; therefore, farmers and their agricultural advisors must insure adequate N is available for the crop to maximize yields and economic returns. Soil contains N in organic (soil orga...
It is widely believed that the rate of profit across industrial sectors, while not in fact uniform as stipulated in the theory of prices of production, is independent of the sectoral organic composition of capital. It follows that the simple labour theory of value must be systematically in error as a predictor of actual sectoral aggregate prices. We offer empirical evidence from the US economy ...
In the previous article [Ammann, K. (2008) Feature: integrated farming: why organic farmers should use transgenic crops. New Biotechnol. 25, 101-107], in a plea for the introduction of transgenic crops into organic and integrated farming, it was announced that the complementary topic, namely that high tech farmers should integrate elements of organic agriculture, will be a follow up. Some selec...
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