植物生态学报 ›› 2018, Vol. 42 ›› Issue (10): 1033-1042.DOI: 10.17521/cjpe.2018.0067

• 研究论文 • 上一篇    下一篇

不同放牧条件下锡林郭勒典型草原土壤水分分布特征及降水入渗估算

李晋波1,姚楠1,赵英1,2,*(),范庭1,张建国1,兰志龙1,易军1,司炳成2   

  1. 1 西北农林科技大学资源环境学院, 农业部西北植物营养与农业环境重点实验室, 陕西杨凌 712100
    2 鲁东大学资源与环境工程学院, 山东烟台 264025
  • 收稿日期:2018-03-29 出版日期:2018-10-20 发布日期:2018-09-26
  • 通讯作者: 赵英
  • 基金资助:
    国家自然科学基金(41371234)

Characteristics of soil water distribution and evaluation of recharge rate under different grazing history in the Xilin Gol Steppe

LI Jin-Bo1,YAO Nan1,ZHAO Ying1,2,*(),FAN Ting1,ZHANG Jian-Guo1,LAN Zhi-Long1,YI Jun1,SI Bing-Cheng2   

  1. 1 Key Laboratory of Plant Nutrition and the Agri-environment in Northwest China, Ministry of Agriculture, Collage of Natural Resource and Environment, Northwest A&F University, Yangling, Shaanxi 712100, China;
    2 School of Resources and Environmental Engineering, Ludong University, Yantai, Shandong 264025, China
  • Received:2018-03-29 Online:2018-10-20 Published:2018-09-26
  • Contact: Ying ZHAO
  • Supported by:
    Supported by the National Natural Science Foundation of China(41371234)

摘要:

由人类活动所导致的锡林郭勒草原草场退化、土地沙化等问题日趋严重, 区域土壤水资源评价及其科学管理显得尤为重要。为确定锡林郭勒典型草原不同放牧条件对深层土壤剖面水分动态及降水入渗补给的影响, 选取1979年以来禁牧(UG79)、1999年以来禁牧(UG99)和持续放牧(CG) 3个小区6个土壤剖面, 基于不同深度土层的质量含水量、Cl -浓度等数据, 分析了放牧对深层土壤水分特征的影响, 且利用氯质量平衡法估算了降水入渗补给量。结果表明: 1)禁牧可以提高土壤含水量, 且禁牧时间越长, 效果越显著, 尤以表层最为明显。整个土壤剖面(0-5 m)土壤质量含水量的平均值表现为UG79 > UG99 > CG, 但各处理间差异不显著; 0-2 m UG79处理土壤剖面质量含水量分别比UG99和CG处理高26.6%和33.7%, 储水量分别高87.19 mm和82.52 mm, 且UG79处理与UG99、CG差异显著, 但UG99与CG之间差异不显著; 除局部地区受土壤颗粒组成影响含水量不同外, 各处理2-5 m土层含水量和储水量差异较小; 2)不同处理土壤含水量影响因素不同, 0-2 m土层含水量主要受地表植被状况和土壤性质的综合影响, 而2-5 m土层则主要受土壤颗粒组成的影响, 但随着禁牧年限的增加, 土壤有机质(SOM)含量对土壤水分的影响越来越大。UG79整个土壤剖面含水量与土壤颗粒含量和SOM含量呈极显著相关关系, UG99与CG处理0-2 m含水量与SOM含量呈极显著相关关系, 2-5 m土壤含水量与土壤颗粒含量呈极显著相关关系, 而与SOM含量相关性不显著; 3)氯质量平衡法估算得出年降水入渗补给率为UG79 > UG99 > CG, 35年和15年禁牧分别将降水入渗补给率提高了130.2%和44.5%; 考虑干沉降的不确定性, 研究区年降水入渗补给率为1.95-7.61 mm·a -1, 仅占年降水量的0.55%-2.13%。总之, 禁牧能够增加土壤含水量和储水量, 增加降水对土壤水分的补给, 但降水不是该区地下水的主要补给源。

关键词: 土壤水分, 降水入渗率, 典型草原, 氯质量平衡法

Abstract:

Aims In the Xilin Gol Steppe, human-induced grassland degradation and land desertification are becoming increasingly severe. Critical evaluation of its impact on soil water and recharge rate is important for sustainable management of soil health and water resources in the region.
Methods In order to determine the effect of different grazing history on dynamics of deep soil moisture contents and precipitation infiltration in the Xilin Gol Steppe, three sites with different grazing history (ungrazed since 1979 or UG79, ungrazed since 1999 or UG99, and continuously grazed or CG) were selected with two sampling spots for each site. The precipitation infiltration was estimated using the chloride mass balance method.
Important findings The results showed that: 1) Average soil water content of 0-5 m was 7.1%, 6.9%, and 6.3% for UG79, UG99, and CG, respectively, with no significant difference. In the soil layer of 0-2 m, the soil water content of UG79 was 26.6% and 33.7% higher than that of UG99 and CG, respectively. The soil water content of UG79 was significantly higher than that of UG79 and UG99 (p < 0.05) with no significant difference between UG99 and CG. The soil water storage capacity of UG79 was 87.19 mm higher than UG99 and 82.52 mm higher than CG. In the deep layer of 2-5 m, no significant difference in the soil water content and the water storage among different grazing history. 2) The factors influencing soil water differed among different grazing treatments. The soil water content was mainly affected by the vegetation conditions and soil properties for the 0-2 m soil layer, but by the composition of soil particles for the 2-5 m soil layer. The effect of soil organic matter (SOM) content on soil water increased with time without grazing. Soil water content of the entire soil profile of UG79 was significantly correlated with soil texture and SOM content (p < 0.01). Soil water content of 0-2 m was significantly correlated with SOM content (p < 0.01), soil water content of 2-5 m was significantly correlated with the soil texture (p <0.01), but soil moisture content of UG99 and CG had no significant correlation with SOM content. 3) Annual recharge rate was 5.64, 3.54, and 2.45 mm·a -1 for UG79, UG99 and CG, respectively. The recharge rate increased by 44.5% and 130.2% for the site without grazing for 15 and 35 years, respectively. The recharge rate in the study area ranged from 1.95 to 7.61 mm·a -1, accounting for only 0.55%-2.13% of the precipitation. In summary, ungrazing treatment can increase soil water retention, total water storage capacity, and recharge.

Key words: soil moisture, recharge rate, steppe, Chloride Mass Balance