堆腐城市生活垃圾对莴笋生长影响的主分量分析

在不同的土壤上，城市生活垃圾对莴笋生长的影响不同。在石灰性土壤上，莴笋产量与垃圾用量间的关系符合对数模型，其边际产量随垃圾用量增加而减少，与一般肥料效应相似；而在强酸性土壤上，莴笋产量与垃圾用量间的关系可用抛物线模型模拟，在试验用量范围内，其边际产量随垃圾用量的增加而增加，显著高于一般肥料效应。通过主分量分析，查明垃圾促进莴笋生长的原因如下：①降低土壤粘性；②改善土壤营养条件；③对于酸性土壤，垃圾

PRINCIPAL COMPONET ANALYSIS FOR THE EFFECT OF URBAN DOMESTIC REFUSE COMPOST ON LETTUCE GROWTH

There are different effects of urban domestic refuse on lettuce growth in different soils. In calcarious soil, the correlations between the refuse application rates and lettuce yield were expressed by logarithmic models perfectly and the marginal yield decreased as the refuse application increased, similar to the effect of fertilizer. In the strong acid soil, however, the correlation can be expressed by parabola model perfectly and the marginal yields increased with the refuse application within the range of the refuse application rates used in the experiment, significant above the effect of general fertilizer.Through principal component analysis, the reasons refuse promoted growth of lettuce were found as follows : ① Since the refuse contains a considerable amount of nutrients, the soils amended with the refuse will provide more nutrients for crops. ② The pH increased in acid soil and the content of clay in soils decreased with refuse application, which will possess favourable effect on vegetables, especially those growing on heavy soil or acid soil. Tab 8, Ref 8