不同保水措施对土壤水、热状况及新植核桃幼树生长的影响

Effects of Different Water Conversation Measures on Soil Water Content,Soil Temperature and Growth of Newly Planted Walnut Tree

为了探索北方退化干旱山地适宜的土壤保水措施,以2年生"绿岭"核桃嫁接苗为试材,进行保水剂、秸秆覆盖和地膜覆盖等保水措施的不同组合处理,研究了不同保水措施对土壤水、热状况及新植核桃幼树生长的影响。结果表明:所有保水措施均能不同程度地提高土壤含水量,表现为多重处理>双重处理>单一处理>对照。地膜覆盖具有保温增温效果;秸秆覆盖具有很好的保温效果,使地温维持较为恒定的状态;保水剂对地温的影响不显著。地膜覆盖可提高新栽树的成活率,秸秆覆盖会降低成活率。地膜覆盖使发芽期提前,秸秆覆盖会使发芽期延迟。到新梢停止生长,保水剂、秸秆覆盖、地膜覆盖、栽植坑内施用保水剂+秸秆覆盖、栽植坑内施用保水剂+地膜覆盖、秸秆覆盖+地膜覆盖、栽植坑内施用保水剂+秸秆覆盖+地膜覆盖处理的新植核桃幼树的新梢平均长度分别为11.22、27.17、16.38、31.51、15.91、27.27、29.31、9.83cm,有秸秆覆盖的处理(秸秆、保+秸、秸+地和保+秸+地)>有地膜覆盖而无秸秆覆盖的处理(地膜和保+地)>保水剂>对照。在干旱太行山区新垦地,栽植核桃苗最适宜的土壤保水措施为:春覆地膜夏覆秸秆。

To determine the suitable soil water conservation measures in arid and degradation mountain regions in north China,biennial‘Lyuling＇grafted walnut seedlings were used as materials to study the effects of different combinations of aquasorb,straw and plastic film on soil moisture,soil temperature and growth of newly planted young walnut trees.The results showed that all the water conservation measures could increase the soil water content in different degrees,and the water retaining effects were multiple processing〉dual treatment〉single processing〉control.Plastic film mulching had the heat insulation and temperature increasing effect;straw mulching had the ideal thermal insulation effect,so as to keep the ground temperature stable;aquasorb had no effect on soil temperature.Plastic film mulching could increase the survival rate of newly planted trees,straw mulch will reduce the survival rate.Plastic mulch would advance the germination period of newly planted walnut trees and straw mulch delayed germination period.Till the shoot growth stopping period,the average shoot lengths of the newly planted walnut trees of each treatments were 11.22 cm,27.17 cm,16.38 cm,31.51 cm,15.91 cm,27.27 cm,29.31 cm and 9.83 cm,those of the treatments that including straw mulching（straw,aquasorb＋straw,straw＋plastic film and aquasorb＋straw＋plastic film）〉the treatments that including plastic film mulching and no straw mulching（plastic film and aquasorb＋plastic film）〉aquasorb〉the control.The suitable soil water conservation measures for planting walnut trees in newly reclaimed regions in the arid Taihang Mountains was using mulching plastic film in spring and mulching straws before the hot and rainy summer.