西方樺 的英文怎麼說
中文拼音 [xīfānghuà]
西方樺
英文
black birch-
Based on the principle of significant effect of soil fertility factors on forest growth, soil physical factors ( natural water content, bulk density, total porosity, capillary porosity, aggregate degree, coarse silt and physical clay ), chemical factors ( om. total n, alkali - hytrolyzable n, total p, humus and ha / fa ) and biological factors ( urease, acidphosphotase, invertase and microbes ) were selected as evaluation index system of soil fertility. applying principal component analysis, soil ifi of subalpine coniferous forest was calculated
從土壤物理、化學、生物學三方面出發，建立了川西亞高山針葉林不同演替階段土壤肥力評價指標體系，應用主成分分析，計算出不同演替階段土壤肥力綜合指標值（ ifi ） ，各演替階段大小順序為： 10年生雲杉林地跡地原始林地次生樺木林地30年生雲杉林地20年生雲杉林地50年生雲杉林地60年生雲杉林地40年生雲杉林地。
分享友人