Effects of compound sand control measures on soil bacterial community structure and function

doi:10.11686/cyxb2023140

Abstract

Abstract:

In this research， the soil of artificial Haloxylon ammodendron forest （Asd） in mobile dune land was taken as the control， and soils from two other compound sand control systems ［nylon grid sand barrier+artificial H. ammodendron forest （Nn） and clay sand barrier+artificial H. ammodendron forest （Cy）］ were selected as experiment treatments. Illumina high-throughput sequencing and PICRUSt2 function prediction technology were used to explore the effects of the compound sand control measures on soil bacterial community structure and function， and redundancy analysis was used to explain the main physical and chemical factors affecting soil bacterial community structure and function. It was found that： 1） The bacterial communities in soil samples from the two composite sand control measures comprised 35 phyla， 90 classes， 172 orders， 259 families and 436 genera. Actinobacteria， Proteobacteria and Chloroflexi were the dominant soil bacterial taxa in the study area， with an average relative abundance of 71.84%. The relative abundance of Actinobacteria was the highest， accounting for 32.16%-37.09%. The occurrences of Bacteroidetes and Cyanobacteria in the Cy plot were significantly higher than those in the Asd plot （P<0.05）. 2） The Chao1 index of soil bacterial diversity in the two plots was significantly higher than that in the mobile dune soil （P<0.05）， but the principal coordinate analysis showed that the soil bacterial community structure of the three plots was similar. 3） Among the 17 secondary functions， carbohydrate metabolism and other functions were the main ecological functions of soil bacteria and showed highly redundant characteristics in different sand control measures areas. 4） Compared with mobile dune soils， the soil organic matter and other nutrients in the area with composite sand control measures showed a common trend of significant increase in bacterial occurrence （P<0.05）， and redundancy analysis showed that physicochemical factors such as soil organic matter and fast-acting potassium levels significantly affected the structure and ecological function of bacterial communities. 5） The dominant phylum among the soil bacteria was significantly correlated with most metabolic functions， and the Mantel test showed a significant positive correlation between differences in soil bacterial community structure and differences in functional potential. In conclusion， the implementation of composite sand control measures improved the desert soil microenvironment， and the research results provide a theoretical basis to manage the ecological restoration of the sandy soil microenvironment.

Key words: soil bacteria, community structure, sand control measures, sandy land restoration

An-lin WANG, Rui MA, Yan-jun MA, Teng LIU, Yong-sheng TIAN, Zheng-hu DONG, Qiao-di CHAI. Effects of compound sand control measures on soil bacterial community structure and function[J]. Acta Prataculturae Sinica, 2024, 33(3): 46-60.

Figures/Tables 14

References 62

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环境因子 Environmental factors	治沙措施 Sand control measures
环境因子 Environmental factors	Asd	Nn	Cy
pH	8.22±0.30b	8.83±0.19a	8.96±0.22a
SOM （g·kg^-1）	1.04±0.07b	1.41±0.13a	1.53±0.30a
TN （g·kg^-1）	0.08±0.01b	0.14±0.03a	0.18±0.03a
TP （g·kg^-1）	0.18±0.02b	0.22±0.04b	0.26±0.03a
AP （mg·kg^-1）	1.25±0.19a	1.33±0.25a	1.36±0.34a
AK （mg·kg^-1）	112.29±11.34b	148.96±14.51a	155.77±18.29a
H （cm）	125.33±11.30c	155.01±8.01b	187.65±17.55a
VG （%）	30.40±2.49b	36.42±2.82a	39.77±3.08a

环境因子 Environmental factors	治沙措施 Sand control measures
环境因子 Environmental factors	Asd	Nn	Cy
pH	8.22±0.30b	8.83±0.19a	8.96±0.22a
SOM （g·kg^-1）	1.04±0.07b	1.41±0.13a	1.53±0.30a
TN （g·kg^-1）	0.08±0.01b	0.14±0.03a	0.18±0.03a
TP （g·kg^-1）	0.18±0.02b	0.22±0.04b	0.26±0.03a
AP （mg·kg^-1）	1.25±0.19a	1.33±0.25a	1.36±0.34a
AK （mg·kg^-1）	112.29±11.34b	148.96±14.51a	155.77±18.29a
H （cm）	125.33±11.30c	155.01±8.01b	187.65±17.55a
VG （%）	30.40±2.49b	36.42±2.82a	39.77±3.08a

功能Function	Asd	Nn	Cy
新陈代谢Metabolism	81.98±0.36a	81.73±0.15a	81.78±0.20a
遗传信息处理Genetic information processing	11.74±0.24a	11.75±0.38a	11.78±0.33a
细胞过程Cellular processes	3.74±0.30a	3.99±0.28a	3.83±0.26a
环境信息处理Environmental information processing	1.98±0.08a	2.06±0.11a	2.03±0.07a

功能Function	Asd	Nn	Cy
新陈代谢Metabolism	81.98±0.36a	81.73±0.15a	81.78±0.20a
遗传信息处理Genetic information processing	11.74±0.24a	11.75±0.38a	11.78±0.33a
细胞过程Cellular processes	3.74±0.30a	3.99±0.28a	3.83±0.26a
环境信息处理Environmental information processing	1.98±0.08a	2.06±0.11a	2.03±0.07a

项目 Item	指标 Index	轴1 Axis 1	轴2 Axis 2	轴3 Axis 3	轴4 Axis 4
土壤细菌群落与理化因子Soil bacterial communities and physicochemical factors	土壤细菌群落特征值Soil bacterial community characteristic values	0.6824	0.0008	0.0004	0.0001
	土壤细菌群落累计解释量Cumulative interpretation of soil bacterial community （%）	68.24	68.32	68.36	68.37
	土壤细菌群落与环境因子的相关性Correlation between soil bacterial community and environmental factors	0.8278	0.6393	0.5542	0.6547
	土壤细菌群落与环境因子累计解释量Cumulative explained amount of soil bacterial community and environmental factors （%）	99.80	99.92	99.97	99.99
	典范特征值Canonical eigenvalue	68.37
	总特征值Total eigenvalue	99.99
土壤细菌代谢功能与理化因子Soil bacterial metabolic functions and physicochemical factors	土壤细菌代谢功能特征值Soil bacterial metabolic function characteristic values	0.3787	0.0390	0.0250	0.0113
	土壤细菌代谢功能累计解释量Cumulative interpretation of soil bacterial metabolic function （%）	37.87	41.77	44.27	45.39
	土壤细菌代谢功能与环境因子的相关性Correlation between soil bacterial metabolic function and environmental factors	0.7772	0.6107	0.5843	0.6210
	土壤细菌代谢功能与环境因子累计解释量Cumulative explained amount of soil bacterial metabolic functions and environmental factors （%）	80.78	89.10	94.43	96.83
	典范特征值Canonical eigenvalue	45.39
	总特征值Total eigenvalue	96.83