搜索结果: 1-3 共查到“农学 northern forests”相关记录3条 . 查询时间(0.046 秒)
Evaluating the effects of physiographic parameters on the road cross section in mountain forests (Case study: northern forests of Iran)
hillside slope rock base soil texture
2016/1/29
Road cross section, as one the main effective factors in relation to fill and cut volume, was effective in costs and disturbance of forest road constructions. In this research, the effect of a few phy...
Analytical hierarchy process to choose the best earthwork machine in northern forests of Iran
best selection earthwork machine environmental criteria analytical hierarchy process northern forests
2015/4/24
This study attempts to use the analytical hierarchy process to choose the most appropriate earthwork machine for slope classes of 30–50% and 50–70%. Required data were collected by pairwise comparison...
Northern Forests Less Effective Than Tropical Forests in Reducing Global Warming（图）
carbon sink global warming Tropical Forests
2007/7/5
June 21, 2007，Forests in the United States and other northern mid- and upper-latitude regions are playing a smaller role in offsetting global warming than previously thought, according to a study appe...