降雨特征对南亚热带马尾松人工林降水分配格局的影响

探究马尾松人工林降雨特征对降水分配格局的影响,为南亚热带人工林经营管理提供科技支撑。依托广西友谊关森林生态系统国家定位观测研究站降水分配观测场,采用野外定位研究方法,以30年马尾松人工林为研究对象,观测了2018年1—12月的林外降雨、林内透流、干流和冠层截留。结果表明:研究区年降雨总量1303.6 mm,马尾松林的透流、干流及截留量分别占同期降雨的60.9%,0.4%,38.7%。产生透流和干流的最小雨量分别为0.4,2.2 mm。4个降雨特征指标中(雨量、雨强、历时和2次降水间隔时间),降雨量在马尾松降水格局分布中影响最大,雨强和历时对透流量、透流率、干流量、冠层截留量及冠层截留率均有显著影响,而2次降水间隔时间仅对透流量、干流量和冠层截留量有显著影响。SPSS多元线性回归分析表明,3个冠层水文分量对降雨特征的响应并非同步,降雨特征对林内透流和截留的影响大于干流。

Effects of Rainfall Characteristics on Rainfall Partitioning in Plantation of Pinus Massoniana in South Subtropical

To provide basic hydrological data for sustainable management of south subtropical forest plantations, we measured rainfall, throughfall, stemflow and canopy interception in a 30-year old Pinus massoniana stand at Guangxi Youyiguan Forest Ecosystem Research Station from January to December 2018. The results showed that total annual rainfall was 1 303.6 mm, with throughfall, stemflow and canopy interception accounting for 60.9%, 0.4% and 38.7% of total rainfall, respectively. The minimum rainfall that produced throughfall and stemflow was 0.4 and 2.2 mm, respectively. Among the four rainfall factors (rainfall amount, rainfall intensity, rainfall duration, and interval time between two rainfall events), rainfall amount had the strongest effect on rainfall distribution pattern. Rainfall intensity and rainfall duration had a significant impact on throughfall, throughfall rate, stemflow, canopy interception, and canopy interception rate. Interval time between two rainfall events only had a significant impact on throughfall, stemflow, and canopy interception. Results of multiple linear regression analysis showed that the responses of the three components of rainfall partitioning to rainfall characteristics were not synchronized, with throughfall and canopy interception being more affected by rainfall characteristics than stemflow.