乌兰布和沙漠地区灌水对成龄霸王生长及光合作用的影响

摘要

[Objective]To reveal the effects of irrigation on growth and photosynthesis of adult Zygophyllum xanthoxylum. [Method]By field test, through different irrigation treatments on Zygophyllum Xanthoxylum in the Experimental Center of Dorestry, CAF, the effects of irrigation amount [Spring irrigation: W1 15 kg/plant,W2 45 kg/plant,W3 75 kg/plant,W4 150 kg/plant, winter irrigation: W5 75 kg/plant, No irrigation (CK) ]on aboveground biomass, RWC, Pn, Tr and WUE were studied under artificial deep pit and subsurface irrigation. [Result]The results showed that with the increase of irrigation water, the ground biomass increasing. Leaf relative water content from large to small were W3, W2, W4, CK, W5, W1. Under natural conditions and artificial irrigation conditions, daily variation of Pn and Tr showed a "twin peak" curve, and there was obvious "midday depression" phenomenon. Pn from large to small were W3, W2, W4, W1,CK, W5;Tr from large to small were W3, W2, W1, W4, W5, CK. WUE from large to small were W3, W2, CK, W1, W5, W4. [Conclusion]Comprehensive analysis showed that the optimum irrigation time was the germination period of Zygophyllum xanthoxylum, and the best irrigation treatment was spring irrigation 75 kg/plant.%[目的]揭示灌水对成龄霸王生长及光合作用的影响.[方法]采用野外试验,通过对中国林科院沙林中心第一实验场植物园中成龄霸王[Zygophyllum xanthoxylum(Burge) Maxim]进行不同灌水量处理,研究人工深层坑渗灌条件下灌水量[开春水: W1 15 kg/株、W2 45 kg/株、W3 75 kg/株、W4 150 kg/株,埋冬水:W5 75 kg/株,无灌溉(CK)]对成龄霸王地上生物量、叶片相对含水量(RWC)、叶片净光合速率(Pn)、蒸腾速率(Tr)和水分利用效率(WUE)的影响.[结果]随着灌水量的增加,成龄霸王地上生物量不断增加;各处理的叶片RWC从大到小依次为W3、W2、W4、CK、W5、W1;自然条件和人工灌水条件下,霸王叶片 Pn、Tr的日变化均呈"双峰"曲线,且有明显的"午休"现象.各处理Pn日均值从大到小依次为W3、W2、W4、W1、CK、W5;Tr日平均值从大到小依次为W3、W2、W1、W4、W5、CK.WUE日平均值从大到小依次为W3、W2、CK、W1、W5、W4.[结论]综合分析,最适宜的灌水时间是成龄霸王萌芽期,最佳的坑渗灌量为开春水75 kg/株.