干旱区研究 ›› 2022, Vol. 39 ›› Issue (2): 605-614.doi: 10.13866/j.azr.2022.02.27

• 生态与环境 • 上一篇    下一篇

民勤青土湖区不同年限退耕地对土壤水分与物种多样性的影响

王佳1(),田青1(),王理德1,2,何洪盛1,宋达成2,郭春秀2   

  1. 1.甘肃农业大学林学院,甘肃 兰州 730070
    2.甘肃省治沙研究所,甘肃 兰州 730070
  • 收稿日期:2021-04-22 修回日期:2021-08-11 出版日期:2022-03-15 发布日期:2022-03-30
  • 通讯作者: 田青
  • 作者简介:王佳(1996-),女,硕士研究生,主要从事林业研究. E-mail: 2507326198@qq.com
  • 基金资助:
    国家自然科学基金项目(31760709);甘肃省重点研发计划(21YF5FA038);甘肃省青年科技基金项目(18JR3RA019)

Effects of different years of returning farmland on soil moisture and species diversity in Minqin Qingtu Lake area

WANG Jia1(),TIAN Qing1(),WANG Lide1,2,HE Hongsheng1,SONG Dacheng2,GUO Chunxiu2   

  1. 1. College of Forestry, Gansu Agricultural University, Lanzhou 730070, Gansu, China
    2. Gansu Desert Control Research Institute, Lanzhou 730070, Gansu, China
  • Received:2021-04-22 Revised:2021-08-11 Online:2022-03-15 Published:2022-03-30
  • Contact: Qing TIAN

摘要:

采用空间代替时间法,对民勤青土湖地区不同年限退耕地(退耕1 a、2 a、4 a、8 a、13 a、20 a、30 a、40 a和CK)土壤水分变化与植被演替特征进行了调查与分析。结果表明:(1) 随退耕年限增加,土壤含水量整体呈先减少后增加再逐渐趋于稳定。(2) 随退耕年限增加,个体数、类群数和Margalef丰富度指数呈波动式下降的趋势;Shannon多样性指数和Pielou均匀度指数总体趋势先增加后减小,再逐渐趋于稳定;Simpson优势度指数整体变化幅度较小,最终呈稳定的趋势。(3) 随退耕年限增加,植物群落经历了地肤→盐生草→狗尾草→骆驼蒿→小叶碱蓬→黑果枸 杞→红砂→盐爪爪的演替过程。(4) Simpson优势度指数和0~20 cm土层土壤含水量呈极显著负相关,Shannon多样性指数和0~20 cm土层土壤含水量呈极显著正相关,但与20~40 cm土层土壤含水量之间相关性不显著;类群数(S)Margalef丰富度指数、Pielou均匀度指数和土壤含水量之间相关性不显著。可见,干旱区植被自然演替取决于0~20 cm土层土壤的含水量。

关键词: 青土湖, 退耕地, 植被自然演替, 土壤含水量, 相关性

Abstract:

Using the spatial instead of temporal method, we investigated the characteristics of soil moisture change and vegetation succession characteristics across different years of abandoned land (returned fields 1 a, 2 a, 4 a, 8 a, 13 a, 20 a, 30 a, 40 a, and CK) in the Qingtu Lake area of Minqin. As the period of abandoned land increased, the soil water content first decreased, then increased and gradually stabilized. Additionally, as the period of abandoned land increased, the number of individuals, number of groups and Margalef richness index tended to decline; the Shannon diversity index and Pielou evenness index increased first, then decreased and gradually stabilized, whereas the Simpson dominance index only minorly changed before stabilizing. Moreover, as the period of returning farmland increased, the plant community followed a succession process: Kochia scopariaHalogeton arachnoideusSetaria viridisPeganum nigellastrumSuaeda microphyllaLycium ruthenicumReaumuria soongaricaKalidium foliatum. Overall, the Simpson dominance index and soil water content in the 0-20 cm soil layer showed a highly significant negative correlation, whereas the Shannon diversity index and soil water content in the 0-20 cm soil layer showed a highly significant positive correlation; however, there was no significant correlation with soil water content in the 20-40 cm soil layer. Additionally, there was no significant correlation between group number, Margalef richness index, Pielou evenness index, and soil water content. As such, natural vegetation succession in arid areas depends on the soil water content in the 0-20 cm soil layer.

Key words: Qingtu Lake, abandoned land, natural succession of vegetation, soil moisture content, correlation