摘要
桤木人工林在山丘区的根瘤固氮活性3～6μmol/(g·h),活性受多种因素影响,变幅相当大,而变化规律仍明显.五年生桤木固氮量1～4mg/(株·h).固氮量取决于结瘤量,pH和质地亦影响显著.壤质的低钙质紫色土固氮能力较高,重壤质的酸性紫色土和黄壤固氮能力较低.十年生桤木林采伐迹地上,桤木固氮改良土壤,并促进后续植物的生长.
The N2-fixation activity of the alder plantation in the hill and mountain region of Sichuan Basin was 3 - 6μmol/(g·h) generally. It was influenced by the developmental stage.tree age. seasonal change and ecological conditions etc. Its variable range was considerable,but regularity was evident. The amount of nitrogen fixation in the 5a alder was 1 - 4mg/(plant·h) and increased with tree age. The magnitude of N2-fixation depended on the weight of nodulation to considerable extent. The interaction of the soil pH, texture with available N respectively was main factor of effect on N2-fixing amount . The pH and available N as a single factor also had significant effect. Overall,higher N2-fixation capacity of symbiont occurred in the loamy and low calcareous purplish soils, but in a heavy loamy or clay acid purplish soils and yellow earth it decreased markedly. The growth rate in height of the Eutommia on land after catting the alder has been better than on the cultivated soils. The alder nitrogen fixation promoted growth of the after crop.
出处
《山地学报》
CSCD
1996年第S1期30-35,共6页
Mountain Research
关键词
桤木
固氮
多元分析
Alder
nitrogen fixation
multivariate analysis
