摘要
利用PT茎流仪、LI-6400光合测定系统和LI-1400气象工作站对黄土高原水蚀风蚀复合区河北杨、小叶杨和山杏3种树木生长季节树干液流特征、叶片蒸腾速率及其环境因子进行测定。结果表明:典型天气3种树种树干液流昼夜节律明显,夜晚有微弱的稳定的树干液流存在,单双峰规律不明显,3树种树干液流启动和停止时刻基本一致,树干液流速率启动时间为7:00左右,停止时间为20:40左右;3树种平均树干液流速率分别为(3.65±0.40)kg.h-1、(2.22±0.21)kg.h-1、(1.63±0.13)kg.h-1,日单株蒸腾耗水量分别为(49.29±5.42)kg、(30.64±2.92)kg、(22.19±1.73)kg;阴雨天气对树木蒸腾耗水影响较大;树干液流与环境因子日变化规律相吻合,树干液流启动和停止特征时刻滞后于各环境因子对应的特征时刻,但滞后时间长短不一,而峰值特征时刻则早于各环境因子对应的特征时刻;树干液流与光合有效辐射、大气温度、土壤温度及风速呈显著正相关,与大气相对湿度呈显著负相关,环境因子与树干液流速率相关性依次排序为:光合有效辐射>大气温度>大气相对湿度>土壤温度>风速。
The paper aimed to study the characteristics of stem sap flow, the transpiration rate and their correlations with the environmental factors for tree species, Populus hopeiensis, P. simonii and Armeniaca ansu in the mixed area with both water and wind erosion on the Loess Plateau of northwestern China. We used PT-stem flow and LI-6400 Photosynthesis systems, and a LI-1400 meteorological station. The stem sap flow was usually weak at nighttime. The regulation of single- peak and multiple-peak was not obvious. The start and ending time of sap flow of the three species were similar, starting at 7：00 am and ended at 8：04 pm. The diurnal stem sap flow rate of P. hopeiensis＇s, P. simonii＇s and A. ansu＇s were （3.65 ± 0.40）, （2.22 ± 0.21 ） and （ 1.63± 0.13 ） kilograms per hour, respectively, resulting in daily water use of （49.29 ± 5.42）, （30.64 ±2.92） and （22.19 ± 1.73 ） kilograms, respectively. Overcast and rainy weather influenced transpiration sharply. The stem sap flow followed the environmental factors closely. The starting and the ending points of the stern sap flow fell behind the corresponding changes of environmental factors with different lags. The peaks of the stem sap flow came ealier than other environmental factors. The stem sap flow had significant positive correlations with photosynthetic active radiation, air temperature, soil temperature and wind speed, but had significant negative correlation with air relative humidity. The rank in influencing sapflow rate among environmental factors in a descending order was ： photosynthetic active radiation, air temperature, air relative humidity, soil temperature and wind speed.
出处
《生态学报》
CAS
CSCD
北大核心
2008年第9期4568-4574,共7页
Acta Ecologica Sinica
基金
国家"十一五"科技支撑计划资助项目(2006BAD09B06)
国家水利部"948"资助项目(20207)~~
关键词
黄土高原
水蚀风蚀复合区
人工植被
树干液流
影响因子
the Loess Plateau
wind-water erosion region
artificial vegetations
stem sap flow
impact factor
