ABSTRACT

Climatic conditions in temperate montane forests vary over multiple temporal scales. This study examines the effects of inter-annual climatic variability on the long-term water balance of a small headwater catchment with gradually changing vegetation characteristics. The research is based on direct observations of basic hydrological variables (precipitation, stream discharge), and process-based modelling of difficult-to-measure variables (forest transpiration, wet canopy evaporation, snow sublimation). The catchment water balance is evaluated in terms of the catchment water storage. The uncertainty of the estimated storage changes is expressed as a convolution of partial uncertainties associated with the individual components of catchment water balance. The results suggest a significant decrease of catchment water storage over the study period. The decrease is assumed to be caused by increasing winter temperatures, resulting in a more frequent occurrence of liquid precipitation and less prominent spring snowmelt. Considering vegetation’s conservative water-balance management proved essential for the studied environment.

摘要

温带山地森林的气候条件在多个时间尺度上有所不同。本研究考察了年际气候变化对植被特征逐渐变化的小源头流域长期水平衡的影响。该研究基于对基本水文变量（降水、河流流量）的直接观察，以及难以测量的变量（森林蒸腾、湿冠层蒸发、雪升华）的基于过程的建模。集水平衡是根据集水蓄水量来评估的。估计蓄水量变化的不确定性表示为与集水区水平衡的各个组成部分相关的部分不确定性的卷积。结果表明，在研究期间集水区蓄水量显着减少。这种减少被认为是由冬季气温升高引起的，导致液体降水更频繁地发生，春季融雪不那么明显。考虑到植被的保守水平衡管理证明对研究环境至关重要。