干旱区研究 ›› 2012, Vol. 29 ›› Issue (4): 641-647.

• 生物资源 • 上一篇    下一篇

荒漠草原不同地形条件下土壤水分和地上生物量的时空分异

方楷1, 宋乃平1, 魏乐1,2, 安慧1   

  1. 1. 宁夏大学西北土地退化与生态恢复国家重点实验室培育基地,宁夏 银川 750021;
    2. 宁夏大学学术期刊中心,宁夏 银川 750021
  • 收稿日期:2011-05-31 修回日期:2011-07-18 出版日期:2012-07-15 发布日期:2012-09-11
  • 通讯作者: 宋乃平. Email: songnp@163.com
  • 作者简介:方楷(1986-), 男, 宁夏银川人, 硕士研究生, 主要从事草地生态恢复方面的研究. E-mail: 295382189@qq.com
  • 基金资助:

    国家自然科学基金项目(30960075) 资助

Spatiotemporal Distribution of Soil Moisture Content and Aboveground Biomass under Different Terrains in Desert Steppe

 FANG  Kai1, SONG  Nai-Ping1, WEI  Le1,2, AN  Hui1   

    1. Breeding Base of State Key Laboratory for Preventing Land Degradation and Ecological Regeneration, Ningxia University, 
      Yinchuan 750021, China; 
    2. Academic Journal Center,  Ningxia University, Yinchuan 750021, China
  • Received:2011-05-31 Revised:2011-07-18 Online:2012-07-15 Published:2012-09-11

摘要: 运用方差分析、多重比较、Pearson相关系数及克里格插值方法,在时间和空间尺度上分析了荒漠草原地形因素对土壤水分及草地生物量异质性的影响以及土壤水分和生物量的关系。结果表明:荒漠草原地区土壤水分垂直分布规律明显,土壤水分的变异系数在0~20 cm最小、60~80 cm最大;地上生物量在整个生长季的空间异质性较大。3种地形条件下土壤水分含量及时空分布格局各不相同,说明地形是土壤水分异质性的关键影响因子;地形对植物的生长动态规律影响很大,却对地上生物量的空间分异影响较小。不同生育期,土壤水分与地上生物量的关系不同,生长初期地上生物量与60~100 cm土壤水分显著负相关,说明生长初期的土壤水分是植物生长的关键影响因子,并且植物生长耗水主要来自60~100 cm土层;生长旺期和末期的生物量与土壤含水量相关性较弱,这可能与干旱区植物耐旱器官的建成有关。

关键词: 荒漠草原, 地形, 土壤水分, 生物量, 时空分布, 盐池, 宁夏

Abstract: It is of significance to investigate soil moisture content and aboveground biomass under different terrains in desert steppe for understanding the effects of terrain on spatiotemporal heterogeneity of soil moisture content and aboveground biomass. Based on the TDR and field survey, we analyzed the heterogeneity of soil moisture content and aboveground biomass under 3 different terrains using the multivariate analyses, such as the oneway ANOVA, multiple comparison and Kriging interpolation. We also used the person correlation coefficient to analyze the relationship between soil moisture content and aboveground biomass and to clarify the effects of soil moisture content in different soil layers on vegetation at different growth stages.  The  results  are as follows: (1) The vertical distribution of soil moisture content was obvious, and CV was the lowest in soil layer of 0-20 cm but the highest in soil layer of  60-80 cm. The spatial heterogeneity of aboveground biomass was significant in whole growth season; (2) Soil moisture content and its spatiotemporal distribution pattern were different among the 3 different terrains, it means that terrain was the key factor affecting soil moisture content; (3) Terrain was not the main factor affecting the spatial variation of grassland productivity, and it affected significantly the dynamic vegetation growth but slightly the aboveground biomass; (4) The relationship between soil moisture content and aboveground biomass was different at different growth stages. Water consumption for vegetation growth at the initial growth stage was mainly from soil layer of 60-100 cm; there was a weak correlation between soil moisture content and biomass at other growth stages, which may be related to the formation time of drought-tolerant organs of plants.

Key words: desert steppe, terrain, soil moisture content, biomass, spatiotemporal, Yanchi country, Ningxia