Soil multitrophic ecological network structure of agroforestry rubber plantation in Xishuangbanna

doi:10.17520/biods.2022626

Abstract

Abstract:

Aims: Monoculture rubber plantations present a serious threat to regional biodiversity by reducing the ecological structure and function of terrestrial ecosystems in Xishuangbanna. The present research was conducted to (1) develop mitigation strategies to improve soil health under land use intensification and (2) to clarify the diversity and network complexity of soil multitrophic organisms under the influence of different land use types.

Methods: We set sampling sites in the following land use types: monoculture rubber plantation (MRP), rubber with Camellia sinensis (RCS), rubber with Flemingia macrophylla (RFM) and tropical rainforest (TRF). We collected soil samples in the dry (March) and wet (September) seasons. Soil physico-chemical properties, soil enzyme activities, litter mass and root mass were measured. Relevant soil organisms at the multitrophic level were selected for network analysis. Co-occurrence network analysis methods were used to elucidate the complexity of different trophic levels of biological networks in the different land use types.

Results: The results showed that: (1) richness of fungi and arthropods in rubber plantations was lower than tropical rainforest but bacteria and nematode were densely populated in RFM; (2) when examining samples collected in the dry season, when compared with MRP, the soil multitrophic biological network complexity of the RCS was significantly higher (the number of edges and nodes increased by 38.26% and 37.59%, respectively). Similarly, the proportion of soil arthropods increased in the network structure. The RFM, when compared to MRP, showed significant increase in the complexity of soil multitrophic biological network (the number of edges and nodes increased by 23.38% and 31.58%, respectively). When examining samples collected in the wet season, RFM showed significantly more connecting and modular centers dominated by herbivorous nematodes, root-knot nematodes, ectomycorrhiza and rhizobia; and (3) RFM showed significant increase in the total soil carbon and nitrogen content in dry season but increase in enzymatic activities of β-1,4-glucosidase and acid phosphatase in the wet season.

Conclusion: Our study provides a methodological approach that can accurately predict biological indicators of soil quality for agro-rubber forests. Moreover, we have generated a comprehensive dataset and technical support for the establishment and improvement of sustainable environmental-friendly rubber plantations.

Key words: Xishuangbanna, land use, agroforestry, soil biota diversity, ecological network

Wenting Wang, Rong Wang, Cuiping Niu, Yang Bai, Xiaodong Yang. Soil multitrophic ecological network structure of agroforestry rubber plantation in Xishuangbanna[J]. Biodiv Sci, 2023, 31(6): 22626.

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URL: https://www.biodiversity-science.net/EN/10.17520/biods.2022626

https://www.biodiversity-science.net/EN/Y2023/V31/I6/22626

Figures/Tables 8

References 62

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测定项目 Item	季节 Season	橡胶林 MRP	橡胶 + 茶树 RCS	橡胶 + 大叶千斤拔 RFM	热带雨林 TRF
土壤总碳 Total carbon (TC, g/kg)	干季 Dry	15.75 ± 1.13^b	17.71 ± 1.38^b	19.47 ± 1.21^ab	22.44 ± 1.78^a
	雨季 Rain	16.29 ± 0.89^b	17.27 ± 1.09^b	18.67 ± 1.07^b	22.25 ± 1.35^a
土壤总氮 Total nitrogen (TN, g/kg)	干季 Dry	1.73 ± 0.09^b	1.87 ± 0.13^b	2.04 ± 0.09^ab	2.34 ± 0.15^a
	雨季 Rain	1.78 ± 0.08^b	1.81 ± 0.10^b	1.98 ± 0.07^b	2.36 ± 0.14^a
土壤总磷 Total phosphorus (TP, g/kg)	干季 Dry	0.35 ± 0.02^a	0.36 ± 0.03^a	0.41 ± 0.04^a	0.36 ± 0.02^a
	雨季 Rain	0.44 ± 0.05^a	0.36 ± 0.03^a	0.38 ± 0.02^a	0.39 ± 0.04^a
β-1,4-葡萄糖苷酶 β-1,4-glucosidase (BG, μmol?g^-1 dry soil?h^-1)	干季 Dry	5.03 ± 1.39^a	2.66 ± 0.33^a	6.31 ± 2.41^a	3.95 ± 0.51^a
	雨季 Rain	3.90 ± 1.41^ab	3.38 ± 0.99^b	8.28 ± 2.31^ab	9.00 ± 2.51^a
β-N-乙酰氨基葡萄糖酶 β-N-acetyl-glucosaminidase (NAG, μmol?g^-1 dry soil?h^-1)	干季 Dry	0.71 ± 0.21^a	0.93 ± 0.14^a	1.07 ± 0.35^a	0.74 ± 0.13^a
	雨季 Rain	0.87 ± 0.27^a	0.46 ± 0.13^a	1.08 ± 0.26^a	1.06 ± 0.28^a
酸性磷酸酶 Acid phosphatase (AP, μmol?g^-1 dry soil?h^-1)	干季 Dry	6.97 ± 1.59^a	5.84 ± 1.08^a	8.73 ± 1.90^a	7.21 ± 1.02^a
	雨季 Rain	4.77 ± 1.06^ab	1.93 ± 0.46^b	5.87 ± 1.51^a	6.38 ± 1.51^a
pH	干季 Dry	5.30 ± 0.13^b	5.27 ± 0.10^b	5.74 ± 0.08^a	5.26 ± 0.12^b
	雨季 Rain	5.09 ± 0.15^ab	4.95 ± 0.10^b	5.45 ± 0.06^a	5.21 ± 0.21^ab
土壤含水量 Soil moisture (SM, %)	干季 Dry	29.18 ± 1.60^a	24.38 ± 1.64^b	26.86 ± 1.40^ab	19.34 ± 1.08^c
	雨季 Rain	35.37 ± 2.17^a	31.49 ± 2.20^a	34.03 ± 2.17^a	33.64 ± 1.75^a
凋落物生物量 Litter mass (LM, kg/m²)	干季 Dry	2.42 ± 0.30^a	3.28 ± 0.60^a	2.25 ± 0.27^a	2.77 ± 0.25^a
	雨季 Rain	0.64 ± 0.13^b	0.89 ± 0.30^ab	0.75 ± 0.09^b	1.25 ± 0.09^a
减少比率 Rate of decrease (%)	6个月 6 months	73.42	72.88	66.66	54.74
根系生物量 Root mass (RM, g/100g)	干季 Dry	0.15 ± 0.05^b	0.17 ± 0.06^b	0.13 ± 0.05^b	0.27 ± 0.06^a
	雨季 Rain	0.50 ± 0.19^a	0.36 ± 0.09^a	0.34 ± 0.12^a	0.47 ± 0.14^a
增加比率 Rate of increase (%)	6个月 6 months	71.00	53.52	62.69	43.62

测定项目 Item	季节 Season	橡胶林 MRP	橡胶 + 茶树 RCS	橡胶 + 大叶千斤拔 RFM	热带雨林 TRF
土壤总碳 Total carbon (TC, g/kg)	干季 Dry	15.75 ± 1.13^b	17.71 ± 1.38^b	19.47 ± 1.21^ab	22.44 ± 1.78^a
	雨季 Rain	16.29 ± 0.89^b	17.27 ± 1.09^b	18.67 ± 1.07^b	22.25 ± 1.35^a
土壤总氮 Total nitrogen (TN, g/kg)	干季 Dry	1.73 ± 0.09^b	1.87 ± 0.13^b	2.04 ± 0.09^ab	2.34 ± 0.15^a
	雨季 Rain	1.78 ± 0.08^b	1.81 ± 0.10^b	1.98 ± 0.07^b	2.36 ± 0.14^a
土壤总磷 Total phosphorus (TP, g/kg)	干季 Dry	0.35 ± 0.02^a	0.36 ± 0.03^a	0.41 ± 0.04^a	0.36 ± 0.02^a
	雨季 Rain	0.44 ± 0.05^a	0.36 ± 0.03^a	0.38 ± 0.02^a	0.39 ± 0.04^a
β-1,4-葡萄糖苷酶 β-1,4-glucosidase (BG, μmol?g^-1 dry soil?h^-1)	干季 Dry	5.03 ± 1.39^a	2.66 ± 0.33^a	6.31 ± 2.41^a	3.95 ± 0.51^a
	雨季 Rain	3.90 ± 1.41^ab	3.38 ± 0.99^b	8.28 ± 2.31^ab	9.00 ± 2.51^a
β-N-乙酰氨基葡萄糖酶 β-N-acetyl-glucosaminidase (NAG, μmol?g^-1 dry soil?h^-1)	干季 Dry	0.71 ± 0.21^a	0.93 ± 0.14^a	1.07 ± 0.35^a	0.74 ± 0.13^a
	雨季 Rain	0.87 ± 0.27^a	0.46 ± 0.13^a	1.08 ± 0.26^a	1.06 ± 0.28^a
酸性磷酸酶 Acid phosphatase (AP, μmol?g^-1 dry soil?h^-1)	干季 Dry	6.97 ± 1.59^a	5.84 ± 1.08^a	8.73 ± 1.90^a	7.21 ± 1.02^a
	雨季 Rain	4.77 ± 1.06^ab	1.93 ± 0.46^b	5.87 ± 1.51^a	6.38 ± 1.51^a
pH	干季 Dry	5.30 ± 0.13^b	5.27 ± 0.10^b	5.74 ± 0.08^a	5.26 ± 0.12^b
	雨季 Rain	5.09 ± 0.15^ab	4.95 ± 0.10^b	5.45 ± 0.06^a	5.21 ± 0.21^ab
土壤含水量 Soil moisture (SM, %)	干季 Dry	29.18 ± 1.60^a	24.38 ± 1.64^b	26.86 ± 1.40^ab	19.34 ± 1.08^c
	雨季 Rain	35.37 ± 2.17^a	31.49 ± 2.20^a	34.03 ± 2.17^a	33.64 ± 1.75^a
凋落物生物量 Litter mass (LM, kg/m²)	干季 Dry	2.42 ± 0.30^a	3.28 ± 0.60^a	2.25 ± 0.27^a	2.77 ± 0.25^a
	雨季 Rain	0.64 ± 0.13^b	0.89 ± 0.30^ab	0.75 ± 0.09^b	1.25 ± 0.09^a
减少比率 Rate of decrease (%)	6个月 6 months	73.42	72.88	66.66	54.74
根系生物量 Root mass (RM, g/100g)	干季 Dry	0.15 ± 0.05^b	0.17 ± 0.06^b	0.13 ± 0.05^b	0.27 ± 0.06^a
	雨季 Rain	0.50 ± 0.19^a	0.36 ± 0.09^a	0.34 ± 0.12^a	0.47 ± 0.14^a
增加比率 Rate of increase (%)	6个月 6 months	71.00	53.52	62.69	43.62

参数 Parameter	干季 Dry season				雨季 Rain season
	橡胶林	橡胶 + 茶树	橡胶 + 大叶千斤拔	热带雨林	橡胶林	橡胶 + 茶树	橡胶 + 大叶千斤拔	热带雨林
	MRP	RCS	RFM	TRF	MRP	RCS	RFM	TRF
边数目 Number of edges	531	860	530	879	557	642	727	707
正相关边数目 Number of positive edges	445	713	461	767	437	538	575	530
负相关边数目 Number of negative edges	86	147	69	112	120	104	152	177
正相关性比例 Proportion of positive edges	0.84	0.83	0.87	0.87	0.78	0.84	0.79	0.75
平均路径长度 Average path length	4.39	4.17	4.90	3.74	4.16	4.39	4.01	4.19
节点数目 Number of nodes	270	334	293	316	270	295	291	299

参数 Parameter	干季 Dry season				雨季 Rain season
	橡胶林	橡胶 + 茶树	橡胶 + 大叶千斤拔	热带雨林	橡胶林	橡胶 + 茶树	橡胶 + 大叶千斤拔	热带雨林
	MRP	RCS	RFM	TRF	MRP	RCS	RFM	TRF
边数目 Number of edges	531	860	530	879	557	642	727	707
正相关边数目 Number of positive edges	445	713	461	767	437	538	575	530
负相关边数目 Number of negative edges	86	147	69	112	120	104	152	177
正相关性比例 Proportion of positive edges	0.84	0.83	0.87	0.87	0.78	0.84	0.79	0.75
平均路径长度 Average path length	4.39	4.17	4.90	3.74	4.16	4.39	4.01	4.19
节点数目 Number of nodes	270	334	293	316	270	295	291	299