Soil Microbial Ecological Evaluation of Walnut with Different Planting Years Based on Principal Component-Cluster Analysis

doi:10.6048/j.issn.1001-4330.2022.02.026

Abstract

Abstract:

【Objective】 To evaluate the soil microbial ecology of walnut in different planting years in southern Xinjiang with a view to provided reference for the analysis of soil degradation and soil microbial ecological health in walnut orchard. 【Method】 Using the method of space-time substitution, walnut trees in Yecheng area were selected as the research object, the changes of soil physical and chemical properties, microbial quantities and soil enzyme activities in time (5,8-10,15,20-25 planting years) and space (at different soil depths) were analyzed, and the principal component-cluster analysis was used for evaluation. 【Result】 With the extension of the planting years of walnut, pH of 0-20 cm and 20-40 cm soils showed an overall acidification trend. The contents of total salt and other nutrients except available phosphorus showed obvious trend of surface accumulation, and the contents of total nitrogen and organic matter decreased at first and then increased. The number of soil cultural bacteria, actinomycetes and fungi also showed trend of surface accumulation. With the extension of planting years of walnut, the number of soil bacteria increased first and then decreased, and the numbers of actinomycetes and fungi increased. The activities of soil urease and sucrase decreased with the increase of soil depth, but there was no obvious change rule with different planting years. Principal component-cluster analysis showed that the comprehensive score of 0-20 cm soil microbial ecology ranked as walnut planting for 15 years > 20-25 years > 8-10 years > 5 years. The comprehensive score of 20-40 cm soil microbial ecology ranked as walnut planting for 20-25 years > 8-10 years > 15 years > 5 years. 【Conclusion】 The microbial ecological conditions of walnut planted in 5 years were the worst. The soil microbial ecological conditions were the best for 15 years of 0-20 cm surface soil and 20-40 cm subsurface soil.

Key words: principal component-cluster analysis; different planting years; soil microbial ecological evaluation; walnut

摘要：

【目的】 评价新疆南疆不同定植年限核桃土壤微生物生态,为分析核桃园土壤退化问题及研究区域土壤微生物生态健康的研究提供参考。【方法】 采用时空互代法,以叶城地区核桃树为研究对象,分析土壤理化性质、微生物数量和土壤酶活性等微生物生态特征在时间(5、8~10、15、20~25 年的定植年限)和空间(0~20 cm和20~40 cm土层)上的变化规律,并采用主成分-聚类分析进行评价。【结果】 随着核桃定植年限的延长,0~20 cm和20~40 cm土壤pH总体呈酸化趋势。土壤总盐和除速效磷外的其余养分含量有明显表聚现象,全氮和有机质含量呈先降低后升高趋势。土壤可培养细菌、放线菌和真菌数量也存在表聚现象,随着核桃定植年限延长,土壤细菌数量呈先升高后降低趋势,放线菌和真菌数量有增长趋势。脲酶和蔗糖酶活性均随土层深度的增加总体降低,但不同定植年限没有明显的变化规律。0~20 cm土壤微生物生态综合得分排名为核桃定植15年>20~25年>8~10年>5年;20~40 cm土壤为核桃定植20~25年>8~10年>15年>5年。【结论】 5年定植的核桃土壤微生物生态条件最差;0~20 cm表层定植15年、20~40 cm亚表层定植20~25年核桃土壤微生物生态条件最好。

关键词: 主成分-聚类分析, 不同定植年限, 土壤微生物生态评价, 核桃

CLC Number:

S664.1

GU Meiying, XU Wanli, MA Kai, Otkur Mahmut, ZHANG Zhidong, ZHU Jing, TANG Qiyong, CHU Min, ZHANG Lijuan. Soil Microbial Ecological Evaluation of Walnut with Different Planting Years Based on Principal Component-Cluster Analysis[J]. Xinjiang Agricultural Sciences, 2022, 59(2): 474-484.

顾美英, 徐万里, 马凯, 欧提库尔·玛合木提, 张志东, 朱静, 唐琦勇, 楚敏, 张丽娟. 基于主成分-聚类分析评价不同定植年限核桃土壤微生物生态[J]. 新疆农业科学, 2022, 59(2): 474-484.

Figures/Tables 7

References 35

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样品 Sample	pH	总盐 Total salt (g/kg)	全氮 Total N (g/kg)	有机质 OM (g/kg)	速效氮 Available N (mg/kg)	速效磷 Available P (mg/kg)	速效钾 Available K (mg/kg)
a-1	8.47±0.03^a	1.50±0.01^b	0.88±0.03^a	12.34±0.15^ab	70.50±0.85^b	5.50±0.53^c	80.00±2.03^d
b-1	8.53±0.04^a	2.00±0.00^a	0.45±0.01^b	8.78±0.23^c	66.00±1.02^b	9.40±0.19^b	117.00±5.34^c
c-1	8.39±0.01^a	1.40±0.01^b	0.75±0.05^a	14.04±0.31^a	99.00±0.73^a	12.80±0.69^a	203.00±7.69^a
d-1	8.41±0.02^a	0.90±0.01^c	1.00±0.02^a	14.51±0.09^a	72.00±0.89^b	6.60±0.71^c	165.00±6.03^b
a-2	8.26±0.01^b	1.40±0.00^a	0.45±0.01^a	7.01±0.18^b	49.50±1.12^b	7.60±0.32^b	82.00±5.47^b
b-2	8.53±0.03^a	1.30±0.01^a	0.38±0.04^b	7.00±0.44^b	189.00±2.36^a	14.80±0.58^a	59.00±2.18^c
c-2	8.49±0.03^a	1.40±0.02^a	0.43±0.01^a	7.65±0.27^b	49.50±0.99^b	12.40±0.81^a	130.00±8.92^a
d-2	8.41±0.02^a	1.30±0.00^a	0.56±0.03^a	9.75±0.14^a	52.50±0.84^b	6.70±0.43^b	136.00±7.05^a

样品 Sample	pH	总盐 Total salt (g/kg)	全氮 Total N (g/kg)	有机质 OM (g/kg)	速效氮 Available N (mg/kg)	速效磷 Available P (mg/kg)	速效钾 Available K (mg/kg)
a-1	8.47±0.03^a	1.50±0.01^b	0.88±0.03^a	12.34±0.15^ab	70.50±0.85^b	5.50±0.53^c	80.00±2.03^d
b-1	8.53±0.04^a	2.00±0.00^a	0.45±0.01^b	8.78±0.23^c	66.00±1.02^b	9.40±0.19^b	117.00±5.34^c
c-1	8.39±0.01^a	1.40±0.01^b	0.75±0.05^a	14.04±0.31^a	99.00±0.73^a	12.80±0.69^a	203.00±7.69^a
d-1	8.41±0.02^a	0.90±0.01^c	1.00±0.02^a	14.51±0.09^a	72.00±0.89^b	6.60±0.71^c	165.00±6.03^b
a-2	8.26±0.01^b	1.40±0.00^a	0.45±0.01^a	7.01±0.18^b	49.50±1.12^b	7.60±0.32^b	82.00±5.47^b
b-2	8.53±0.03^a	1.30±0.01^a	0.38±0.04^b	7.00±0.44^b	189.00±2.36^a	14.80±0.58^a	59.00±2.18^c
c-2	8.49±0.03^a	1.40±0.02^a	0.43±0.01^a	7.65±0.27^b	49.50±0.99^b	12.40±0.81^a	130.00±8.92^a
d-2	8.41±0.02^a	1.30±0.00^a	0.56±0.03^a	9.75±0.14^a	52.50±0.84^b	6.70±0.43^b	136.00±7.05^a

土层 Soil layer	相关系数 Correlation coefficient	pH	总盐 Total salt	全氮 Total N	有机质 OM	速效氮 Available N	速效磷 Available P	速效钾 Available K
0~20 cm	Bacteria	0.982^**	0.711	-0.628	-0.921^**	-0.841^*	-0.362	-0.744
	Actinomycetes	-0.521	-0.916^**	0.906^**	0.709	-0.173	-0.608	0.103
	Fungi	0.720	0.315	-0.398	-0.655	-0.849^*	-0.383	-0.415
	Urease	0.683	0.228	0.038	-0.455	-0.898^*	-0.878^*	-0.956^**
	Invertase	-0.546	-0.174	-0.160	0.311	0.732	0.860^*	0.955^**
20~40 cm	Bacteria	0.336	-0.361	-0.734	-0.658	0.937^**	0.680	-0.935^**
	Actinomycetes	0.326	-0.526	0.740	0.948^**	-0.255	-0.304	0.774
	Fungi	0.023	-0.824^*	0.747	0.814^*	0.055	-0.456	0.256
	Urease	0.475	-0.784	0.598	0.856^*	0.081	-0.121	0.507
	Invertase	-0.831^*	0.426	-0.134	-0.515	-0.124	-0.361	-0.546

土层 Soil layer	相关系数 Correlation coefficient	pH	总盐 Total salt	全氮 Total N	有机质 OM	速效氮 Available N	速效磷 Available P	速效钾 Available K
0~20 cm	Bacteria	0.982^**	0.711	-0.628	-0.921^**	-0.841^*	-0.362	-0.744
	Actinomycetes	-0.521	-0.916^**	0.906^**	0.709	-0.173	-0.608	0.103
	Fungi	0.720	0.315	-0.398	-0.655	-0.849^*	-0.383	-0.415
	Urease	0.683	0.228	0.038	-0.455	-0.898^*	-0.878^*	-0.956^**
	Invertase	-0.546	-0.174	-0.160	0.311	0.732	0.860^*	0.955^**
20~40 cm	Bacteria	0.336	-0.361	-0.734	-0.658	0.937^**	0.680	-0.935^**
	Actinomycetes	0.326	-0.526	0.740	0.948^**	-0.255	-0.304	0.774
	Fungi	0.023	-0.824^*	0.747	0.814^*	0.055	-0.456	0.256
	Urease	0.475	-0.784	0.598	0.856^*	0.081	-0.121	0.507
	Invertase	-0.831^*	0.426	-0.134	-0.515	-0.124	-0.361	-0.546

土层 Soil layer	因子 Factor	因子载荷Factor loadings			特征向量Eigenvectors of matrix
土层 Soil layer	因子 Factor	PC₁	PC₂	PC₃	PC₁	PC₂	PC₃
0~20 cm	Bacteria	-0.977^**	0.119	0.174	-0.370	0.060	0.171
	Actinomycetes	0.336	-0.890^*	0.307	0.127	-0.446	0.301
	Fungi	-0.741	-0.052	0.670	-0.280	-0.026	0.655
	pH	-0.975^**	0.223	0.015	-0.369	0.112	0.015
	Total salt	-0.685	0.690	-0.233	-0.259	0.346	-0.228
	Total N	0.524	-0.848^*	-0.081	0.198	-0.425	-0.079
	OM	0.875	-0.483	-0.048	0.331	-0.242	-0.047
	Available N	0.862^*	0.422	-0.282	0.326	0.212	-0.276
	Available P	0.483	0.875^*	0.029	0.183	0.439	0.029
	Available K	0.868^*	0.338	0.365	0.328	0.169	0.357
	Urease	-0.827^*	-0.541	-0.152	-0.313	-0.271	-0.149
	Invertase	0.700	0.582	0.414	0.265	0.292	0.405
20~40 cm	Bacteria	-0.735	0.567	0.373	-0.295	0.284	0.275
	Actinomycetes	0.940^**	0.313	-0.133	0.378	0.157	-0.099
	Fungi	0.748	0.340	0.570	0.301	0.171	0.421
	pH	-0.014	0.883^*	-0.469	-0.006	0.443	-0.347
	Total salt	-0.367	-0.788	-0.494	-0.148	-0.395	-0.365
	Total N	0.919^**	-0.283	0.273	0.369	-0.142	0.202
	OM	0.994^**	0.076	0.078	0.399	0.038	0.058
	Available N	-0.505	0.819^*	0.271	-0.203	0.411	0.200
	Available P	-0.608	0.681	-0.409	-0.244	0.341	-0.302
	Available K	0.833^*	-0.243	-0.497	0.335	-0.122	-0.368
	Urease	0.812^*	0.581	0.056	0.326	0.291	0.042
	Invertase	-0.512	-0.652	0.559	-0.206	-0.327	0.413