干旱内陆河浅山区典型小流域降水径流观测与模拟

The arid shallow mountain area is the transitional zone of inland river basin between the alpine region and plain oasis. The relationship between precipitation and runoff is ambiguous because of lacking hydrological observation data, which caused deviation for accurate calculation of water resources for the mountainous area of inland river basin. Based on this, we will establish meteorological and hydrological observation system in a typical small catchment in shallow mountain area of arid inland river basin in this research. Then, the experiment and observation for rainfall-runoff processes will be implemented, and the temporal-spatial characteristic and the main influence factor of rainfall-runoff will be analyzed, to develop a distributed hydrological model which can accurately simulate the rainfall-runoff processes of shallow mountain area of arid inland river basin. We will simulate the rainfall-runoff processes of the study area using the developed distributed hydrological model to clarify the processes and mechanisms of the rainfall-runoff and the rule of runoff generation. The implementation of this research will promote the research level of the calculation of rainfall-runoff of the shallow mountain area which was an empirical level to a distributed hydrological level which is based on clear physical process, and the weakness of the hydrology research of inland river basin will be supplemented. The results of this research may provide reference for fine management of the water resources of inland river basin.

干旱内陆河浅山区是高山区与山前绿洲平原的过渡带，由于缺少水文观测资料，在水资源评估中该区的径流量往往依据经验进行估算，降水径流关系不清楚，导致出山径流量的计算具有很大的不确定性，给中游绿洲水资源量的准确评价造成误差。基于此，本项目拟选择干旱内陆河浅山区典型小流域建立水文观测系统，对降水径流过程进行观测与试验，并分析降水径流时空动态特征与产流影响因素，建立干旱内陆河浅山区小流域分布式水文模型，并基于观测数据对水文过程进行模拟与验证，最终阐明干旱内陆河浅山区小流域降水径流的过程机制与规律，并准确计算出山径流量，为内陆河流域精细水资源管理提供科学依据。

浅山区是内陆河流域山区的重要组成部分，是山区与绿洲平原的过渡地带，由众多狭长沟壑型小流域组成，面积占内陆河流域山区的16.2%。内陆河大部分浅山区小流域无常年性径流，但有季节性径流和暴雨洪水事件，由于缺少水文观测资料，以往水资源评估中浅山区的水资源量往往依据经验进行估算。降雨径流关系不清楚，导致浅山区径流量的计算具有很大的不确定性，给中游绿洲水资源量的准确评价造成误差。因此，本项目选择内陆河浅山区典型小流域（大口子沟小流域）进行降雨径流要素观测并模拟降雨径流过程，旨在厘清内陆河浅山区降雨径流要素的时空分布规律。本项目取得的主要进展包括：（1）建立了较为完备的浅山区小流域降雨径流观测系统，包括：自动气象站6套、小型量水堰2座、地下水观测点1个、土壤温湿度监测点5个，收集了近4年的连续观测资料；（2）对试验观测和实验室分析的数据进行了降雨径流时空特征与产流影响因素分析，获得了小流域内不同海拔梯度、不同坡向、不同植被覆盖类型条件下的降雨、土壤温湿度等要素的空间差异及时间变化过程；（3）收集了研究区内DEM、土壤类型属性数据、通过遥感解译了植被覆盖类型数据，结合观测的相关参数，建立了模型驱动数据集，并建立了小流域降雨径流过程模型，对干旱内陆河浅山区小流域的降雨径流过程进行了模拟，并基于观测数据对建立的模型进行了验证与评价。. 该项目获取的气象要素梯度变化规律、土壤特征数据等能够干旱内陆河浅山区水文过程模拟提供重要参数，为进一步准确计算内陆河浅山区水资源量提供依据，具有一定的应用价值。