Assessing influence of simulated canopy nitrogen deposition and understory removal on soil microbial community structure in a Cunninghamia lanceolata plantation

doi:10.17520/biods.2018033

Abstract

Abstract:

Soil microorganisms have been recognized as important decomposers that link above- and below-ground processes in terrestrial ecosystems. In this study, we conducted an experiment to assess the influence of canopy nitrogen deposition and understory removal in a Cunninghamia lanceolata plantation. The effects of four treatments, i.e. control (CK), understory removal (UR), nitrogen deposition (N) and nitrogen deposition plus understory removal (N × UR) on soil microbial community were investigated using phospholipid fatty acids (PLFAs). Soil samples (0-10 layer) were collected in April (spring) and October (autumn), 2016. Results showed that the total soil microbial PLFAs and the other groups (bacteria, fungi and actinomycete) of soil microbial PLFAs in autumn were significantly higher than those in spring, but fungi/bacteria ratio did not change significantly between two sampling seasons. Bacteria dominated among different PLFAs groups, followed by fungi and actinomycetes. Relative to CK treatment, UR treatment had slightly higher total PLFAs, bacterial PLFAs, gram negative bacterial PLFAs and actinomycetes PLFAs although not significant at 0.05 level. Shannon-Wiener and Pielou indices of UR, N and N × UR treatments decreased in April whereas Shannon-Wiener index was higher in October. Soil nitrate nitrogen and total phosphorus were significantly correlated with soil microbial community based on redundancy analysis. No significant effect of nitrogen deposition was observed probably due to the short period of study. But understory removal seems to promote the impact of nitrogen deposition. Seasonal variations were detected in this study suggesting that long-term experiments are required to explore the continuing effects of environmental changes on soil microbial communities and their functions.

Key words: soil microbial community, biodiversity, nitrogen deposition, understory removal, Cunninghamia lanceolata plantation

Xueming Lei, Fangfang Shen, Xuechen Lei, Wenfei Liu, Honglang Duan, Houbao Fan, Jianping Wu. Assessing influence of simulated canopy nitrogen deposition and understory removal on soil microbial community structure in a Cunninghamia lanceolata plantation[J]. Biodiv Sci, 2018, 26(9): 962-971.

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URL: https://www.biodiversity-science.net/EN/10.17520/biods.2018033

https://www.biodiversity-science.net/EN/Y2018/V26/I9/962

Figures/Tables 7

References 48

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微生物类型 Microbial group	特征磷脂脂肪酸 Phospholipids fatty acid characteristics	参考文献 References
细菌 Bacteria	i15:0, a15:0, 15:0, i16:0, 16:1 ω9c, 16:1 ω7c, 16:1 ω7t, i17:0, 17:0, a17:0, cy 17:0, 18:1 ω5c, 18:1 ω7c, i19:0, cy 19:0	Frostegård & Bååth, 1996; Zogg et al, 1997; Marhan et al, 2007; Wu et al, 2013a, b
革兰氏阳性菌 Gram-positive bacteria	i14:0, i15:0, a15:0, i16:0, i17:0, a17:0	Zak et al, 1996; Yang et al, 2016
革兰氏阴性菌 Gram-negative bacteria	16:1 ω7c, cy 17:0, 18:1 ω7c, cy 19:0	Zak et al, 1996; Wu et al, 2013a, b
真菌 Fungi	18:1 ω9c, 18:2 ω6c, 18:3 ω6c	Frostegård & Bååth, 1996
放线菌 Actinomycetes	10Me 16:0, 10Me 17:0, 10Me 18:0	Zak et al, 1996

微生物类型 Microbial group	特征磷脂脂肪酸 Phospholipids fatty acid characteristics	参考文献 References
细菌 Bacteria	i15:0, a15:0, 15:0, i16:0, 16:1 ω9c, 16:1 ω7c, 16:1 ω7t, i17:0, 17:0, a17:0, cy 17:0, 18:1 ω5c, 18:1 ω7c, i19:0, cy 19:0	Frostegård & Bååth, 1996; Zogg et al, 1997; Marhan et al, 2007; Wu et al, 2013a, b
革兰氏阳性菌 Gram-positive bacteria	i14:0, i15:0, a15:0, i16:0, i17:0, a17:0	Zak et al, 1996; Yang et al, 2016
革兰氏阴性菌 Gram-negative bacteria	16:1 ω7c, cy 17:0, 18:1 ω7c, cy 19:0	Zak et al, 1996; Wu et al, 2013a, b
真菌 Fungi	18:1 ω9c, 18:2 ω6c, 18:3 ω6c	Frostegård & Bååth, 1996
放线菌 Actinomycetes	10Me 16:0, 10Me 17:0, 10Me 18:0	Zak et al, 1996

	处理 Treatment	含水率 SWC (%)	pH	有机碳 SOC (g/kg)	全氮 TN (g/kg)	全磷 TP (g/kg)	硝态氮 NO₃^--N (mg/kg)	铵态氮 NH₄⁺-N (mg/kg)	速效磷 AP (mg/kg)
春季 Spring	CK	40.85 ± 2.14^Aa	4.45 ± 0.11^Aa	41.16 ± 3.55^Aa	2.29 ± 0.19^Aa	0.19 ± 0.01^Bab	0.06 ± 0.01^Ab	10.97 ± 1.21 ^Aa	5.20 ± 0.60^Aa
	UR	40.80 ± 4.38 ^Aa	4.35 ± 0.01^Aa	36.08 ± 2.86^Aa	2.04 ± 0.16^Aab	0.21 ± 0.01^Ba	0.05 ± 0.01^Ab	10.74 ± 1.07^Aa	4.91 ± 0.99^Aa
	N	32.26 ± 2.41^Aa	4.34 ± 0.01^Aa	30.74 ± 4.77^Aa	1.70 ± 0.21^Ab	0.17 ± 0.01^Bb	0.09 ± 0.04^Ab	12.79 ± 2.47^Aa	3.37 ± 0.55^Aa
	N × UR	33.76 ± 2.16^Aa	4.40 ± 0.01^Aa	38.53 ± 2.82^Aa	2.20 ± 0.13^Aab	0.20 ± 0.01^Bab	0.21 ± 0.07^Aa	15.29 ± 1.65^Aa	4.04 ± 0.52^Aa
秋季 Autumn	CK	38.99 ± 3.26^Aa	4.70 ± 0.19^Aa	37.92 ± 5.78^Aa	1.75 ± 0.62^Aa	0.83 ± 0.09^Aa	0.20 ± 0.05^Aa	3.80 ± 0.35^Ba	1.38 ± 0.72^Ba
	UR	34.81 ± 1.54^Aa	4.39 ± 0.06^Aa	37.73 ± 7.78^Aa	2.15 ± 0.53^Aa	0.57 ± 0.11^Ab	0.15 ± 0.02^Aa	4.46 ± 0.32^Ba	3.46 ± 1.07^Aa
	N	32.35 ± 2.12^Aa	4.37 ± 0.03^Aa	28.57 ± 3.95^Aa	2.03 ± 0.46^Aa	0.55 ± 0.07^Ab	0.22 ± 0.02^Aa	4.22 ± 0.40^Ba	0.98 ± 0.33^Ba
	N × UR	35.75 ± 2.73^Aa	4.35 ± 0.05^Aa	34.81 ± 1.76^Aa	2.20 ± 0.30^Aa	0.87 ± 0.10^Aab	0.33 ± 0.09^Aa	4.21 ± 0.36^Ba	2.52 ± 1.01^Aa

	处理 Treatment	含水率 SWC (%)	pH	有机碳 SOC (g/kg)	全氮 TN (g/kg)	全磷 TP (g/kg)	硝态氮 NO₃^--N (mg/kg)	铵态氮 NH₄⁺-N (mg/kg)	速效磷 AP (mg/kg)
春季 Spring	CK	40.85 ± 2.14^Aa	4.45 ± 0.11^Aa	41.16 ± 3.55^Aa	2.29 ± 0.19^Aa	0.19 ± 0.01^Bab	0.06 ± 0.01^Ab	10.97 ± 1.21 ^Aa	5.20 ± 0.60^Aa
	UR	40.80 ± 4.38 ^Aa	4.35 ± 0.01^Aa	36.08 ± 2.86^Aa	2.04 ± 0.16^Aab	0.21 ± 0.01^Ba	0.05 ± 0.01^Ab	10.74 ± 1.07^Aa	4.91 ± 0.99^Aa
	N	32.26 ± 2.41^Aa	4.34 ± 0.01^Aa	30.74 ± 4.77^Aa	1.70 ± 0.21^Ab	0.17 ± 0.01^Bb	0.09 ± 0.04^Ab	12.79 ± 2.47^Aa	3.37 ± 0.55^Aa
	N × UR	33.76 ± 2.16^Aa	4.40 ± 0.01^Aa	38.53 ± 2.82^Aa	2.20 ± 0.13^Aab	0.20 ± 0.01^Bab	0.21 ± 0.07^Aa	15.29 ± 1.65^Aa	4.04 ± 0.52^Aa
秋季 Autumn	CK	38.99 ± 3.26^Aa	4.70 ± 0.19^Aa	37.92 ± 5.78^Aa	1.75 ± 0.62^Aa	0.83 ± 0.09^Aa	0.20 ± 0.05^Aa	3.80 ± 0.35^Ba	1.38 ± 0.72^Ba
	UR	34.81 ± 1.54^Aa	4.39 ± 0.06^Aa	37.73 ± 7.78^Aa	2.15 ± 0.53^Aa	0.57 ± 0.11^Ab	0.15 ± 0.02^Aa	4.46 ± 0.32^Ba	3.46 ± 1.07^Aa
	N	32.35 ± 2.12^Aa	4.37 ± 0.03^Aa	28.57 ± 3.95^Aa	2.03 ± 0.46^Aa	0.55 ± 0.07^Ab	0.22 ± 0.02^Aa	4.22 ± 0.40^Ba	0.98 ± 0.33^Ba
	N × UR	35.75 ± 2.73^Aa	4.35 ± 0.05^Aa	34.81 ± 1.76^Aa	2.20 ± 0.30^Aa	0.87 ± 0.10^Aab	0.33 ± 0.09^Aa	4.21 ± 0.36^Ba	2.52 ± 1.01^Aa

	处理 Treatment	微生物总量 Total PLFAs	细菌量 Bacterial PLFAs	革兰氏阳性菌量 G⁺ PLFAs	革兰氏阴性菌量 G^-PLFAs	真菌量 Fungal PLFAs	放线菌量 Actinomycetes PLFAs	真菌:细菌 F/B ratio
春季 Spring	CK	75.01 ± 5.44^Ba	21.02 ± 1.47^Aa	10.21 ± 0.61^Ba	8.21 ± 0.61^Aa	8.07 ± 1.21^Aa	4.91 ± 0.29^Aa	0.38 ± 0.04^Aa
	UR	78.63 ± 4.87^Ba	22.37 ± 2.15^Aa	11.87 ± 0.73^Ba	7.97 ± 0.94^Aa	7.80 ± 1.80^Aa	5.42 ± 0.31^Aa	0.34 ± 0.06^Aa
	N	71.09 ± 12.45^Ba	20.06 ± 4.30^Aa	9.89 ± 2.30^Ba	7.58 ± 1.52^Aa	7.80 ± 1.53^Aa	4.83 ± 1.14^Aa	0.40 ± 0.01^Aa
	N × UR	58.14 ± 7.12^Ba	16.44 ± 2.40^Ba	8.40 ± 1.41^Ba	5.92 ± 0.72^Ba	5.54 ± 0.54^Ba	3.63 ± 0.68^Ba	0.35 ± 0.02^Aa
秋季 Autumn	CK	132.03 ± 10.74^Ab	25.58 ± 1.59^Aa	22.38 ± 2.08^Aa	8.63 ± 0.78^Aa	8.56 ± 1.16^Aa	5.69 ± 0.26^Aa	0.34 ± 0.05^Aa
	UR	166.28 ± 9.36^Aa	28.11 ± 2.60^Aa	24.90 ± 2.23^Aa	9.58 ± 1.21^Aa	10.62 ± 0.68^Aa	6.02 ± 0.39^Aa	0.38 ± 0.02^Aa
	N	134.77 ± 14.07^Aab	26.24 ± 2.39^Aa	22.96 ± 2.75^Aa	8.51 ± 0.87^Aa	9.66 ± 1.04^Aa	5.87 ± 0.87^Aa	0.37 ± 0.03^Aa
	N × UR	128.27 ± 10.60^Ab	26.97 ± 3.75^Aa	22.26 ± 1.88^Aa	9.07 ± 1.40^Aa	9.99 ± 1.14^Aa	6.04 ± 0.90^Aa	0.38 ± 0.04^Aa