Estimation of the ecological water requirement for natural vegetation in the Ergune River basin in Northeastern China from 2001 to 2014
Estimation of the ecological water requirement for natural vegetation in the Ergune River basin in Northeastern China from 2001 to 2014
复制标题
2001-2014年东北额尔古纳河流域自然植被生态需水量估算
DOI：
10.1016/j.ecolind.2017.04.014
复制
发表时间：
2018-09-01
影响因子：
6.9
通讯作者：
Li, Xiaohui
中科院分区：
文献类型：
--
作者：
Chi, Dengkai;Wang, Hong;Li, Xiaohui
植被是盆地最基本的组成部分。因此，植被生态需水量（EWR）直接影响流域水资源的合理配置。本文将Penman-Monteith方法与GIS和遥感技术相结合，动态计算植被系数，并引入土壤水分限制系数，为自然植被EWR的计算提供了完整而准确的方法。然后计算了额尔古纳河流域植被的EWR和生态水分亏缺（EWD）并分析了时空变化。 （1）主要植被类型为针叶林、阔叶林、草原、草甸四种，占流域总面积的87%。 EWR分别为2.11×10(10)m(3)、0.76×10(10)m(3)、3.39×10(10)m(3)和10(10)m(3)。 (2)2001—2014年针叶林和阔叶林蒸散量分别减少7.93 mm a(-1)和6.88 mm a(-1),而草本植被则呈现小幅增加趋势。额尔古纳河流域植被总EWR几乎没有变化。 (3)额尔古纳河流域植被缺水分布广泛。这是由于研究区半干旱和寒冷的条件，降水量无法满足植被的EWR。呼伦湖北部、海拉尔河东部、额尔古纳河干流西部地区植被缺水胁迫较为突出，可通过雨水收集措施缓解。 (4)确定EWR的分布与生长季降水的时间分配不一致。初期和发展阶段水分亏缺胁迫均较高，后期相对较低。我们发现呼伦湖水系（额尔古纳河流域的一个分区）的植被在各个阶段都经历了严重的缺水。我们建议通过建造蓄水库来储存雨水，以供旱季使用。
Vegetation is the most basic component of a basin. The ecological water requirement (EWR) of vegetation consequently has a direct impact on the judicious allocation of water resources in basin. In this paper, we combined the Penman-Monteith method with GIS and remote sensing techniques to dynamically calculate the vegetation coefficient and introduced the soil moisture limitation coefficient, which together provides a complete and accurate approach in calculating the EWR of natural vegetation. We then calculated the EWR and the ecological water deficit (EWD) of vegetation in the Ergune River basin and analyzed spatiotemporal variations. (1) The four main vegetation types were coniferous forest, broad-leaved forest, steppe, and meadow, which accounted for 87% of the basin's total area. EWR were 2.11 x 10(10) m(3), 0.76 x 10(10) m(3), 3.39 x 10(10) m(3), and 10(10) m(3), respectively. (2) Evapotranspiration from coniferous and broad-leaved forests decreased by 7.93 mm a(-1) and 6.88 mm a(-1) from 2001 to 2014, respectively, while herbaceous vegetation exhibited a slightly increasing trend. Total EWR of vegetation in the Ergune River Basin remained almost unchanged. (3) The water deficit of vegetation in the Ergune River basin was widely distributed. This was due to the semi-arid and cold conditions of the study area, where precipitation could not meet the EWR of vegetation. Water deficit stresses on vegetation were more prominent in the northern Hulun Lake, the eastern Hailar River, and the western mainstream section of the Ergune River, which could be alleviated by rainwater harvesting measures. (4) We determined that the distribution of EWR and the time allocation of precipitation in growth season were incongruous. Water deficit stresses were high in both the initial and developing stages, while it was relatively low in the latter stage. We found it was in the Hulun Lake System (sub-region of the Ergune River basin) that vegetation experienced a significant water deficit during all stages. We recommend to store rainwater by constructing water storage repositories for use in dry seasons.