黄土高原8种树种蒸腾速率与日蒸散量比较

Studies on Transpiration Rate and Evapotranspiration of 8 Tree Species in the Loess Plateau

以侧柏、华北落叶松、油松、新疆杨、臭椿、核桃、枣树、榆树为研究对象,在2006年7月,对供试苗木进行定时的称重、蒸腾观测。一天中,其平均蒸腾速率的大小为:新疆杨>臭椿>华北落叶松>侧柏>榆树>油松>核桃>枣树,日蒸散量的大小依次为新疆杨>侧柏>臭椿>华北落叶松>油松>核桃>枣树>榆树,蒸腾速率大者蒸腾耗水不一定大,反之亦然。新疆杨、臭椿的耗水量较大;侧柏、落叶松和油松耗水量较少、抗旱性较强;榆树、枣树和核桃,耗水量居中,应大力提倡种植,且作为经济树种可增加当地群众的收入。

The dissertation chose Patycladusorientalis, Larixprina piam-rupprechtii , Pinus tabulae formis , Populus bolleana , Ailanthusaltissirna,Zizyphus jujube,Ulmus pumila and Juglans regia on the Loess Plateau to be our subjects. In July of 2006, we had their transpiration rate and other factors. The results show：in one day, the decreasing orders of average transpiration rate of the eight tree species is Populus bolleana 〉 Ailanthus altissima 〉 Larix prinapiam-rupprechtii 〉 Patycladus orientalis〉 Ulmus pumila 〉 Pinus tabulaeformis 〉 Juglans regia 〉 Zizyphus jujube. But the decreasing orders of average daily evapotranspiration is Populus bolleana 〉 Patycladus orientalis 〉 Ailanthus altissima 〉 Larix prinapiam- rupprechtii 〉 Pinus tabulae formis 〉 Juglans regia 〉 Zizyphus jujube 〉 Ulmus pumila. So we can see that the average transpiration rate and the average daily evapotranspiration of the eight tree species is not consistent,when the former was high,the later maybe very low,just so so. The results also show that the Populus bolleana and the Ailanthu saltissima consume more water than other species,Patycladus oriental is, Larix prinapiam-rupprechtii and Pinus tabulaeformis consume lower water, the Ulmus pumila ,Zizyphus jujube and Juglans regia don＇t consume lots of water and have economic benefit to local people, so they are precede to other tree species.