若尔盖泥炭小流域地下水水位的时空变化规律

若尔盖泥炭湿地是黄河上游重要的水源涵养地，发挥着蓄水、固碳和生态的重要功能。近几十年来若尔盖泥炭湿地面积持续萎缩，其地下水水位的变化对湿地萎缩发挥着关键性作用。选取若尔盖高原的黑河上游泥炭湿地典型小流域，采用HOBO自记水位计布设5个靠近沟道和3个远离沟道的地下水水位观测点，结合2017年5-9月地下水水位观测数据以及红原站气象资料，分析该小流域内地下水水位的时空变化规律。结果表明：沟道可为周边泥炭层提供更加长效的补水时间，而且能够更快汇集地表水流；远离沟道的地下水水位变化与降雨过程趋于同步，其与降雨量的相关系数达到0.8；洼地的地下水水位变化比坡地受降雨影响小；地下水水位变化对降雨过程具有滞后响应，即随着降雨强度增大，滞后时长逐渐减小，且远离沟道比靠近沟道的观测点的滞后时长要短约18 min。

Spatio temporal variation of groundwater level in a small Zoige peatland catchment

The Zoige peatland is an important water conservation area in the upper reaches of the Yellow River, which plays a vital role of water storage, carbon sequestration, and ecological protection in the basin. The area of the Zoige peatland has been shrinking continuously during recent decades, which is mainly caused by the changes of its groundwater level. Here, taking a typical small peatland catchment in the upper Black River in Zoige Plateau as an example, we set up five monitoring points close to the natural channels and three away from them using the HOBO water level recorders. Analysis of the spatio temporal variation of groundwater levels in this small catchment was carried out based on the monitored groundwater level data of May-September 2017 and the meteorological data of Hongyuan Station. Results reveal that the natural channels can provide a longer effective time of water replenishment for the surrounding peat layer and they can accumulate the surface water flow faster. The change of groundwater level at the monitoring points away from the channels tended to be synchronized with the rainfall process, with the correlation coefficient between the groundwater level and rainfall reaching 0.8. The groundwater level change in the low lying land was less likely to be affected by precipitation than that in the slope land. The change of groundwater level had a lag response to the rainfall process, with the increase of rainfall intensity, the lag time gradually decreased, and the lag time of the monitoring points far away from the channels was about 18 min shorter than those close to the channels.