The Remediation Mode for the Polluted Land in Inner Mongolia

This paper discusses the method of contaminated soil remediation technologies at home and abroad,analyzes the soil restoration situation in Inner Mongolia,and puts forward some suggestions on the development direction of soil repair industry for Inner Mongolia.The research methods of this article include literature review,summarization of data,comparison and analysis,and generalization and summarization.The soil restoration has made certain achievements in Inner Mongolia in recent years.But the technical level and policy level are still very imperfect,having not reached the national average.Some recommendations are proposed.The first is to improve soil repair local laws,regulations and technical standards.The second is to increase investment in scientific research in the field of soil restoration,and the introduction of new technology,to encourage independent innovation.The third is to fix soil combined with related industrial projects and avoid redundant construction.The last one is to intensify propaganda to improve public consciousness of the soil pollution prevention and control.

Review of regional carbon counting methods for the Chinese major ecological engineering programs

In order to improve environment and relieve poverty, China has launched a series of major ecological engineering programs since the 1980 s. These include the Natural Forest Conservation Program, the Sloping Cropland Conversion Program, the Desertification Combating Program, and the Protection Forest System Construction Program. There is a growing need to quantify the contributions of these programs to regional carbon stocks.However, the lack of widely accepted, robust methods is one of the key obstacles to quantification. The objective of this study was to review existing methods for quantifying regional carbon stocks and then recommend suitable ones for the Chinese ecological engineering programs. We expect that the recommended methods can be applied to elsewhere in the world where there are similar characteristics and objectives.

Deep soil water infiltration and its dynamic variation in the shifting sandy land of typical deserts in China

Soil moisture is the key resource constraint in arid ecosystems, and has been a focus of research on restoration. However, quantitative studies on the contribution of rainfall to deep soil rainfall infiltration are lacking. In this study, we used the YWB-01 Deep Soil Infiltration Water Recorder which had been invented by ourselves to measure the quantity of rain infiltration into deep soil, 150 cm below ground, in four locations in China: Mu Us Sandy Land and Ulan Buh, Tengger, and Badan Jilin deserts over a 2-year period. We found:(1) Deep soil rainfall infiltration decreased progressively from east to west and from semiarid to arid areas, with two locations completely lacking rainfall infiltration. Heavy rain was important to deep soil infiltration in shifting sandy land of arid and semiarid areas.(2) Seasonal variation of infiltration was correlated with rainfall, with a time lag that was less apparent in areas with more rainfall.(3) For single intense rainfall events, infiltration maximums occurred 40–55 h after the rainfall, during which the infiltration rates increased rapidly before reaching a peak, and then decreased slowly. Continuous infiltration could last about 150 h. Rainfall infiltration was determined by the combined action of intensity, quantity and duration. Rainfall with low intensity, long duration, and large quantity was most favorable for deep soil infiltration. Our results can be used in water resource assessments and protection during eco-restoration in the arid and semiarid areas in China.

气候因子调节荒漠土壤中丰富和稀有微生物群落的聚集过程

土壤微生物由少数的丰富类群和大量的稀有类群组成,它们对生态系统的功能和服务有不同的贡献。本研究采用高通量测序技术对荒漠土壤样品的物种组成进行DNA测序分析,揭示土壤微生物丰富类群和稀有类群的组成结构。采用相关性分析和随机森林方法进一步分析环境因子对丰富和稀有类群群落的影响。最后,利用基于零模型的β-最近类群指数(βNTI)解析土壤微生物的群落构建机制。研究结果表明,在荒漠土壤中,稀有细菌的群落构建几乎完全由确定性的同质选择过程支配;相比之下,随机过程对丰富细菌的影响更为明显。然而,无论是丰富真菌还是稀有真菌都表现出相似的群落构建模式,即确定性过程和随机过程共同决定了真菌的群落构建过程。这些结果表明,随着平均年降水量(MAP)和平均年气温(MAT)的增加,丰富细菌的群落构建过程从随机性转变为确定性。而对稀有真菌来说,随着MAT的增加,群落构建过程从确定性向随机性转变。该研究提供了MAT和MAP调节荒漠土壤中丰富和稀有微生物群落构建过程的明确证据。这些发现为进一步研究土壤微生物群落结构和生态功能奠定了理论基础。