黄土区草被生长过程中土壤抗冲性及其与影响因素的关系

发布时间：2018-07-31 13:14

【摘要】：采用室内盆栽与原状土冲刷相结合的方法,设置了裸地对照(CK)、低种植密度黑麦草(H1)和高种植密度黑麦草(H2)3种处理,对3种处理在不同生长阶段的土壤理化性质和根系变化进行研究,分析了黄土区草被生长过程中土壤抗冲性及其与影响因素的相关关系。结果表明:(1)处理CK的容重、有机质含量和水稳性团聚体在4个生长阶段波动变化,但变化范围较小;随生长周期的延长,H1和H2处理的土壤容重呈下降趋势,有机质含量、水稳性团聚体、根表面积密度(RSAD,root surface area density)和根生物量密度(RWD,root weight density)呈增加趋势;在4个生长阶段,H1和H2处理各根径的RSAD表现为随根系径级的增大而减小。(2)CK和H2处理的土壤抗冲指数(ASI,anti-scourability index)在4个生长阶段无显著性变化;H1处理的ASI随生长时间的延长表现为逐渐增加的趋势,且在第16周,对ASI的影响最显著。(3)ASI与土壤容重呈幂函数递减关系,与有机质含量、水稳性团聚体呈幂函数递增关系,与RSAD、RWD之间均呈指数递增函数关系。(4)ASI与容重、水稳性团聚体、1.0~2.0,2.0~5.0,5mm径级的RSAD之间均无显著差异,与有机质含量、RSAD及RWD呈显著正相关(p0.05),与1mm径级的RSAD呈极显著正相关(p0.01)。
[Abstract]:Three treatments of low density ryegrass (H1) and high density ryegrass (H2) were set up by using pot culture and scouring of undisturbed soil. The soil physical and chemical properties and root system changes of three treatments in different growth stages were studied, and the relationship between soil erosion resistance and influencing factors during the growth of grass cover in loess region was analyzed. The results showed that: (1) the bulk density of CK, organic matter content and water-stable aggregate fluctuated in the four growth stages, but the range of change was small, and the soil bulk density decreased with the increase of growth cycle, and the organic matter content decreased with the extension of the growth cycle. The root surface area density (RSAD root surface area density) and root biomass density (RW DX root weight density) of water-stable aggregates showed an increasing trend. (2) the soil anti-scourability index of CK and H2 treatments had no significant change in the four growth stages. The ASI of H1 treatment decreased with the growth time. (2) the soil anti-scourability index of CK and H _ 2 treatments had no significant change during the four growth stages. The length of the root diameter of H1 treatment decreased with the increase of root diameter. (2) the soil anti-scourability index of CK and H _ 2 treatments had no significant change during the four growth stages. Long shows a gradual increasing trend, In the 16th week, the effect of ASI on ASI was most significant. (3) ASI showed a power function decreasing relationship with soil bulk density, a power function increasing relationship with organic matter content and water stable aggregate, and an exponential increasing function relationship between ASI and RSAD RWD. (4) ASI and bulk density. There was no significant difference between the RSAD of water stable aggregates (1.0 ~ 2.0 ~ 2.0 ~ 5.0 ~ 5.0mm), but there was a significant positive correlation (p0.05) with the content of organic matter and RWD, and a very significant positive correlation with the RSAD of 1mm (p0.01).
【作者单位】：陕西师范大学旅游与环境学院;
【基金】：国家自然科学基金项目“黄土区典型乡土草本植物对土壤侵蚀动力学过程的调控机理研究”(41571260);国家自然科学基金项目“黄土丘陵沟壑区植物间正相互作用对坡面植被格局的影响”(41501290) 陕西省自然科学基金项目“黄土高原草被控制坡沟系统径流侵蚀动力机制及有效性研究”(2014KJXX-52)
【分类号】：S157

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