不同水分处理下防护林树种叶水势、茎水势及土水势的研究

摘要

[Objective] This study took the tree species of protection forest from the big agricultural region in Karamay as experimental materials to investigate leaf, stalk and soil water potential to the tree species of protection forest under different water treatments. [ Method ] Two different furrow irrigation treatments ( with 50 m3 /(each·667 m2 )and 100 m3/(each·667 m2)irrigation volume, respectively) were set, and diurnal variations to investigate leaf, stalk and soil water potential to the tree species of protection forest were measured. [Result] Diurnal variations in leaf water potential, Popoulus Russkii Jabl and Elaeagus oxycarpa Schlecht S leaf water potential are respectively - 2.03 Mpa and - 3.23 Mpa with treatment one at 08 ;00, leaf water potential are respectively 3. 32 Mpa and - 11. 65 Mpa at 20; 00. Leaf water potential of Elaeagus oxycarpa Schlecht decreased significantly; Popoulus Russkii Jabl and Elaeagus oxycarpa Schlecht 's leaf water potential did not decrease significantly with the two treatments from 08:00 am to 20; 00 pm. The stalk water potential and leaf water potential is similar under different water treatments; Soil water potential at the soil depth (from 30 cm to 90 cm) increased with the rise of soil depth (decline in Elaeagus oxycarpa Schlecht) , while the tree roots'ability to absorb moisture decrease with soil depth (from 30 cm to 90 cm) increased ( Rise in Elaeagus oxycarpa Schlecht). [ Conclusion]From the changes of the leaf, stalk and soil water potential, drought - tolerance degrees of the tree species of protection forest are Elaeagus oxycarpa Schlecht > Populus euphratica Oliv > Ulmus pumila L. > Popoulus Russkii Jabl. Main factors are related to the tree species of protection forest itself ( such as leaf area, root, etc. ). When to irrigate the trees remained to be researched in future.%[目的]以克拉玛依防护林树种为试材,探讨不同水分处理下不同防护林树种的叶水势、茎水势和土水势的日变化及其相关性.[方法]试验设置2种水分处理(沟灌):处理一(50 m3/(667 m2·次))和处理二(100 m3/(667 m2·次)),采用露点水势仪测定防护林树种的叶水势、茎水势和土水势的日变化.[结果]叶水势日变化中,处理一在08:00时俄罗斯杨和沙枣树的叶水势分别为-2.03和- 3.23 MPa,在20:00时叶水势分别为-3.32和- 11.65 MPa,沙枣树叶水势下降明显；处理二08:00 ～20:00俄罗斯杨和沙枣树的叶水势下降均不明显.二种处理树种茎水势日变化与叶水势变化相似；土水势随着土壤深度(30～90 cm)的增加呈上升趋势(沙枣树下降),树种根系吸收水分能力随着土壤深度(30 ～90 cm)的增加而下降(沙枣树吸收水分增强).[结论]从叶、茎及土水势变化来看,树种抗旱程度为沙枣树＞胡杨＞白榆＞俄罗斯杨,主要原因与树种自身因素(如叶面积,根系等)有关.