نتایج جستجو برای: abandoned lands
تعداد نتایج: 19924 فیلتر نتایج به سال:
Concentrations of cellulose, lignin and nutrients in the stemwood of four clones of 7-year-old hybrid aspen (Populus tremula L. x P. tremuloides Michx.) were studied on 50 permanent experimental plots established for the afforestation of abandoned agricultural lands in Estonia. Quantitative evaluation of hybrid aspen chemical components indicated a relatively high cellulose and low acid-insolub...
The demand for agricultural products continues to grow rapidly, but further agricultural expansion entails substantial environmental costs, making recultivating currently unused farmland an interesting alternative. The collapse of the Soviet Union in 1991 led to widespread abandonment of agricultural lands, but the extent and spatial patterns of abandonment are unclear. We quantified the extent...
Soil bacterial community structures in terraced rice fields and abandoned lands in a hilly and mountainous area were analyzed using 16S rRNA gene sequences. The DGGE band patterns of each soil were similar. Based on pyrosequencing data, the richness and diversity of bacterial species were slightly higher in paddy fields than in other soils. A beta-diversity analysis clearly indicated that the b...
The extent and distribution of global forests is a matter of considerable concern. The overall rate of deforestation remains high although recent reports suggest it is fi nally beginning to decline (FAO 2011 ) . But this hides regional differences. In temperate regions net forest cover is increasing because of afforestation and natural expansion of forests. By contrast, net forest cover in most...
A sink for atmospheric carbon (i.e., CO2) in soils may derive from the application of conservation tillage and the regrowth of native vegetation on abandoned agricultural land. Accumulations of soil organic matter on these lands could offset emissions of CO2 from fossil fuel combustion, in the context of the Kyoto protocol. The rate of accumulation of soil organic matter is often higher on fert...
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