نتایج جستجو برای: soil conservation measures
تعداد نتایج: 624460 فیلتر نتایج به سال:
Variation of streamflow and sediment load in the Yellow River basin has received considerable attention due to its drastic reduction during the past several decades. This paper presents a detailed investigation on the changes of streamflow and sediment load from 1952 to 2011 using monthly observations at four gauging stations along the Yellow River. The results show significant decreasing trend...
In dryland cropping systems, optimal yields require that nutrient supply matches the soil’s yield potential supported by available moisture. Conservation tillage systems that leave at least 30 percent of the soil surface covered by residue dramatically increase moisture retained in the soil compared to crop-fallow systems. This enables producers to plant two, three, or four consecutive crops, o...
Elevated atmospheric carbon dioxide (CO2) can affect both the quantity and quality of plant tissues produced, which will impact the cycling and storage of carbon (C) within plant/soil systems and thus the rate of CO2 release back to the atmosphere. Research is needed to more accurately quantify the effects of elevated CO2 and associated feedbacks on soil CO2 efflux in order to predict the poten...
Most of the current studies on soil conservation measures mainly focus their control effect, neglecting impact water quantity. In present study, latest seven years (2014–2020) monitored data from 22 runoff plots in upstream catchment Miyun Reservoir, Beijing were used to evaluate effects slope, rainfall, and loss, some implications given this water-scarce region. Excluding measures, loss increa...
The concept of integrity, as a factor which sustains values and significance of cultural heritage, is regarded as a key criterion in the process of urban heritage conservation and thus, the need for clarification of its factors has been emphasized in the international conventions, documents and scientific papers. Review and analysis of documents, conventions and theories concerning the role ...
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