自然资源学报 ›› 2021, Vol. 36 ›› Issue (2): 490-500.doi: 10.31497/zrzyxb.20210217

• 其他研究论文 • 上一篇    下一篇

东部湿润区典型小流域土地利用的土壤水效应

周才钰(), 许有鹏(), 刘鹏飞, 王强, 王杰   

  1. 南京大学地理与海洋科学学院,南京 210023
  • 收稿日期:2019-06-05 修回日期:2019-11-20 出版日期:2021-02-28 发布日期:2021-04-28
  • 通讯作者: 许有鹏 E-mail:caiyu615@163.com;xuyp305@163.com
  • 作者简介:周才钰(1996- ),女,陕西汉中人,硕士,研究方向为水文水资源学。E-mail: caiyu615@163.com
  • 基金资助:
    国家重点研发计划专项项目(2018YFC1508201);国家自然科学基金项目(41771032)

Effect of land use types on soil moisture in typical small watershed of humid region of Eastern China

ZHOU Cai-yu(), XU You-peng(), LIU Peng-fei, WANG Qiang, WANG Jie   

  1. School of Geography and Ocean Science, Nanjing University, Nanjing 210023, China
  • Received:2019-06-05 Revised:2019-11-20 Online:2021-02-28 Published:2021-04-28
  • Contact: XU You-peng E-mail:caiyu615@163.com;xuyp305@163.com

摘要:

不同土地利用类型下土壤水变化机制对流域水文过程与生态环境有较大影响。基于我国东部湿润区野外综合观测土壤墒情数据,探讨了不同土地利用类型下土壤水的动态变化特征。结果表明:(1)总体上,杨梅林土壤含水量在32%~37%之间波动;农田土壤含水量在20%~30%波动。坡耕地土壤含水量稳定在27%~35%之间;竹林土层土壤含水量大致稳定在25%~32%之间。垂直剖面上,表层(10 cm、20 cm)土壤水分变化大,深层(60~80 cm)土壤水分变化较小。表层土壤水分时间变化特征的波动幅度较深层土壤大。(2)不同降雨强度下,竹林土壤水分对降雨的响应程度大于杨梅林、农田和坡耕地。降雨强度越大,土壤水分响应程度越大;降雨停止后,土壤水分消退起伏下降,深层土壤水分变化较表层稳定。(3)通过增墒系数和减墒系数对土壤水分变化进行量化,发现竹林的消退最明显,其余三种土地利用类型变化幅度相当。杨梅林、农田和竹林均是表层变化较深层大,坡耕地变化更为复杂。研究结果将为我国东部湿润地区产汇流机理及防洪减灾研究提供一定参考。

关键词: 土壤水分, 降雨, 土地利用类型, 湿润区小流域

Abstract:

The urbanization process in Eastern China has been accelerating in recent years, leading to underlying surface changes affecting soil moisture in the region. Knowledge of soil moisture is critical to understanding many of the hydrological processes that are of interest in soil hydrology, meteorology, and ecology research. Long-term time series of in situ soil moisture measurements themselves can reveal trends in the water cycle related to climate or land cover change. In this study, we used rainfall and soil moisture data collected at waxberry forests, bamboo forests, farmland, and slope cropland sites in the Hualong River region of Eastern China in 2015 to 2018 to analyse the response of soil moisture to rainfall event size at different soil depths. The results showed the following: (1) In general, the soil moisture content of waxberry forests was slightly higher than that of farmland, slope cropland, and bamboo forests. In the vertical section, the soil moisture in the surface layer (10-20 cm) changed greatly while the soil moisture in the deep layer (60-80 cm) changed little. Meanwhile, the temporal variation of surface soil moisture was larger than that of deep soil moisture. (2) Under different rainfall intensities, the soil moisture of bamboo forests responded more substantially to rainfall than did waxberry forests, farmland, and slope cropland. The greater the rainfall intensity, the greater the response degree of soil moisture. The soil moisture was in a fluctuant downward trend after the rainfall stopped. (3) Quantification of soil moisture by increasing coefficient and reducing coefficient demonstrated that the bamboo forest had the most obvious regression. The other three types of land use varied equally. The soil moisture of waxberry forests, farmland, and bamboo forests changed more dramatically at the surface layer than at the deeper depths. In addition, the soil moisture in the deep layer of slope cropland was affected by the infiltration of surface soil water in the process of regression; this change was complicated, which needs further studies. These research results provide a theoretical basis for the quantitative description of the soil hydrological conversion process, the mechanism of runoff and stream flow, agricultural production, and water resources allocation in the monsoonal Eastern China.

Key words: soil moisture, rainfall, land use types, humid watershed