摘要
:
Grapevines are extensively grown in the arid region of China, but little information is available on the diurnal, seasonal and interannual variability of vineyard evapotranspiration (<i>ET</i>). To address this question, two viney...
展开
Grapevines are extensively grown in the arid region of China, but little information is available on the diurnal, seasonal and interannual variability of vineyard evapotranspiration (<i>ET</i>). To address this question, two vineyards in the arid region of northwest China were taken as an example to study the variation of <i>ET</i> using Bowen ratio-energy balance method in 2005-2008. Results indicate that the Bowen ratio method provided accurate estimate of vineyard <i>ET</i> as the instrument was correctly installed. Irrigation and rainfall increased daily <i>ET</i> by 38 and 175%, respectively, but frost decreased it by 32%. Daily <i>ET</i> had a maximum value of 1.6-3.5 mm/d at the berry development stage, and a minimum value of 0.8-1.7 mm/d at the early and later stages. The total <i>ET</i> was 226-399 mm over the growing season. The ratio of transpiration to evapotranspiration was 0.52 and the modified crop coefficient (<i>K</i><i><sub>cm</sub></i>) was 0.71-0.88 (except 2005) over the whole growing stage. Larger interannual difference of <i>ET</i> and <i>K</i><i><sub>cm</sub></i> mainly resulted from the difference of irrigation and rainfall between different years.
收起