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题名	地带性多年冻土区小流域水文状况对水热季节变化的响应
作者	邴龙飞
答辩日期	2008-05-23
文献子类	博士
授予单位	中国科学院沈阳应用生态研究所
授予地点	沈阳应用生态研究所
关键词	小流域 活动层 蒸散 多年冻土 时间序列分析 融深
其他题名	Response of Hydrological Situation to the Seasonal Hydro-Temperature Changes of the Small Watershed in Permafrost Area
英文摘要	It’s the only part of the zonal permafrost of China in the northern great Hing’an Mountains, which lies in the south of the zonal permafrost in the great continent of Eurasia, and is sensitive to the global changes. The global changes will affect the soil water content of the permafrost, as well affect the hydrological phenomenon of the small watershed in it. It’s the small watershed that is the key object related to the zonal research. The changes of the active layer will result in chaos in the hydrological phenomenon of the small watershed. This research based on the DEM, then some small was divided. Several factors was discussed to simplify the equation of Water balance of the small watershed, such as precipitations, evapotranspirations and the principles of the soil water content, which developed some evidence for further research. The conclusion lists below. 1) The rise of the average temperature will affect the distribution of the soil water content in permafrost surly, as a result, some hydrological mechanism will change by it. 2) There is something relationships between the melt depth of the permafrost and the elevation. The melt depth increases while the elevation rising gradually. But there is no obvious relationship between the soil water contents and the altitude. The precipitation almost centered on from May to October. There is usually more precipitation in November and December, with a lower temperature as a result of ice precipitation form, than that in spring. The soil water content of the active layer change greatly in different altitude, which is relative to the natural surroundings. 3) There is an obvious periodical fluctuation. And almost no significant difference is observed in the same time between different years. There is a gradually increase in evapotranspiration from the beginning to the middle of the year, exception for some fine irregularities. The evapotranspiration changes very quickly from January to April, something like linear relationship. But from the middle of April to the middle of September, ET0 became fluctuant. From the middle of April on, the evapotranspiration became increase fluctuantly, to the climax in July around. Then it went down, and it would follow an linear relationship from the middle of September or the beginning of October. 4) The change of soil water content ΔW can be expressed as follows: ;where ΔW stands for the change of soil water content; R stands for the flux in the outlet of the small watershed; Rn stands for the net radiation; N stands for daylight hours; c is constant. All the result can be used for further research on the response of the wetland water content in permafrost to temperature changes in a year, which will also be useful for global change studies.; 大兴安岭北部是我国唯一一片地带性连续多年冻土分布区，也是欧亚大陆地带性多年冻土分布区的南缘，因此对气候变化的响应十分敏感。全球变暖必然会影响到冻土土壤水分状态的变化，从而对冻土区的流域水文状况产生影响；小流域是区域研究的主要对象，冻土活动层变化的最直接后果就是引起流域内水文状况发生变化。本研究利用DEM数据划分小流域，在划分出的小流域的基础上，探讨了影响流域流量变化的几个因子，包括降水、蒸散(Evapotranspiration, ET)和土壤持水，初步简化了流域水量平衡方程，可为进一步研究提供基础。主要包括以下方面的内容： a)平均温度的升高必然会影响到冻土土壤水分状态的变化，从而导致区域小流域水文状况随之变化； b)融深与海拔高度存在一定的相关关系，融深随海拔的升高而增加；土壤水分随海拔变化的规律并不明显。年内降水主要集中在每年的5月份到10月份；11月份和12月份降水一般比春季的多，这两个月份气温很低，降水形式主要是雪。不同地点不同海拔下冻土活动层土壤水分含量变化很大，这和当地的环境条件有关，如地表覆被、土壤类型、坡度、坡向等。 c)参考植被蒸散呈明显的周期性波动规律。每年同期蒸散大致维持在同一水平上。从年初到年中，流域内蒸散呈不断增加的趋势。但是变化规律又稍有不同，每年大致从1月份到4月份，蒸散随时间变化很快，几乎呈线性增加。但是从4月中旬开始，到下半年的9月中旬，ET0呈震荡变化趋势。4月中旬开始，蒸散开始震荡增加，到7月份左右达到最大，然后开始震荡降低，大约到9月中旬或10月初开始转为近似线性减少趋势。 d)土壤水分含量的变化ΔW可以表示为下式：ΔW=R-(0.260Rn-0.036N) Kc+c；其中，ΔW为土壤水分含量的变化；R流域出口处流量；Rn为太阳净辐射；N为白昼长度；Kc植被系数；c为常数。 上述研究结果可以为进一步分析年内冻土湿地水分状况对温度变化的响应提供基础，也可为气候变化条件下冻土湿地水文过程的响应研究提供参考。
语种	中文
公开日期	2010-12-15
页码	80
内容类型	学位论文
源URL	[http://210.72.129.5/handle/321005/2713]
专题	沈阳应用生态研究所_沈阳应用生态研究所
推荐引用方式 GB/T 7714	邴龙飞. 地带性多年冻土区小流域水文状况对水热季节变化的响应[D]. 沈阳应用生态研究所. 中国科学院沈阳应用生态研究所. 2008.

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