摘要
明晰沙地人工植被蒸腾耗水规律,对于荒漠化地区生态建设具有至关重要的意义。本研究应用热扩散式插针茎流计(TDP)与自动气象站,对科尔沁沙地人工杨树林树干液流及周边环境因子进行了长期监测,分析了杨树液流的动态变化规律,揭示了液流与环境因子的响应关系。结果表明:液流日变化基本呈单峰"几"字型曲线,偶尔会出现多峰曲线;不同气象条件对液流速率具有明显影响,晴天液流速率最大,阴天次之,雨天最小;生长季液流速率与太阳辐射强度、饱和水汽压差和空气温度呈较强正相关关系,决定系数R^2分别为0.88、0.81和0.76,与空气相对湿度呈显著负相关,决定系数R^2为0.79;结合各气象因子建立Penman-Monteith(P-M)模型对杨树林地的潜在蒸散发能力进行模拟并结合树干液流实测数据进行验证,结果显示模拟效果精度较高,决定系数R^2为0.83;对地下水位变化情况进行监测显示,杨树蒸腾耗水主要依赖于地下水,地下水位在杨树蒸腾能力较强的9:00-18:00下降明显,随后水位出现不同程度的回升现象。
It is important to clarify the transpiration and water consumption of artificial vegetation for ecological construction in desertification area.In this study,we used thermal dissipation probe(TDP)and automatic weather stations to monitor long-term trunk sap flow of a poplar plantation and environmental factors in Horqin sandy land.We analyzed the dynamics of poplar sap flow and the relationship between sap flow and environmental factors.The results showed that the diurnal variation of sap flow generally followed a normal distribution,and occasionally a multi-peak curve.Weather conditions affected sap flow rate,with highest values on sunny days and lowest values on rainy days.In the growing season,sap flow rate was positively correlated with solar radiation intensity,saturated water vapor pressure difference and air temperature,with correlation coefficients R^2 of 0.88,0.81 and 0.76,respectively.There was a negative correlation between sap flow rate and air relative humidity,with a R^2 of 0.79.The Penman-Monteith(P-M)model was constructed to simulate the potential evapotranspiration of poplar plantation and verified with the filed data.The results showed that the simulation effect was of high precision,with a R^2 of 0.83.Water consumption of poplar via evapotranspiration mainly depended on groundwater.The groundwater level dropped obviously accompanied by strong evapotranspiration of poplar during9:00-18:00,after which groundwater level rose to some extent.
作者
贾天宇
刘廷玺
段利民
张亦然
童新
包永志
JIA Tian-yu;LIU Ting-xi;DUAN Li-min;ZHANG Yi-ran;TONG Xin;BAO Yong-zhi(College of Water Conservancy and Civil Engineering,Inner Mongolia Agricultural University,Hohhot 010018,China;Key Laboratory of Inner Mongolia Water Resource Protection and Utilization,Hohhot 010018,China)
出处
《生态学杂志》
CAS
CSCD
北大核心
2020年第10期3255-3264,共10页
Chinese Journal of Ecology
基金
国家自然科学基金项目(51620105003、51479086和51869017)
内蒙古自然科学基金重点项目(2018ZD05)
教育部创新团队发展计划(IRT_17R60)
科技部重点领域科技创新团队(2015RA4013)
内蒙古自治区草原英才产业创新创业人才团队
内蒙古农业大学寒旱区水资源利用创新团队(NDTD2010-6)资助。
