Differential magnitude of rhizosphere effects on soil aggregation at three stages of subtropical secondary forest successions

被引：40

作者：

Liu, Ruiqiang ^{[1
]}

Zhou, Xuhui ^{[1
,2
]}

Wang, Jiawei ^{[1
]}

Shao, Junjiong ^{[1
]}

Fu, Yuling ^{[1
]}

Liang, Chao ^{[3
]}

Yan, Enrong ^{[1
]}

Chen, Xiaoyong ^{[1
]}

Wang, Xihua ^{[1
]}

Bai, Shahla Hosseini ^{[4
,5
]}

机构：

[1] East China Normal Univ, Sch Ecol & Environm Sci, Tiantong Natl Field Stn Forest Ecosyst Res, Shanghai Key Lab Urban Ecol Proc & Ecorestorat, Shanghai 200062, Peoples R China

[2] East China Normal Univ, Ctr Global Change & Ecol Forecasting, Shanghai 200062, Peoples R China

[3] Chinese Acad Sci, Inst Appl Ecol, Key Lab Forest Ecol & Management, Shenyang 110016, Liaoning, Peoples R China

[4] Univ Sunshine Coast, Fac Sci Hlth Educ & Engn, Maroochydore, Qld 4558, Australia

[5] Cent Queensland Univ, Sch Med & Appl Sci, Bundaberg, Qld 4670, Australia

来源：

PLANT AND SOIL | 2019年 / 436卷 / 1-2期

基金：

中国国家自然科学基金;

关键词：

Forest chronosequence; Forest age; Fine-root traits; Soil aggregate stability; Soil organic carbon; ARBUSCULAR MYCORRHIZAL FUNGI; MICROBIAL COMMUNITIES; FUNCTIONAL TRAITS; ORGANIC-CARBON; PLANT-ROOT; STABILITY; NITROGEN; MATTER; RESTORATION; FERTILITY;

D O I：

10.1007/s11104-019-03935-z

中图分类号：

S3 [农学（农艺学）];

学科分类号：

0901 ;

摘要：

Background and aimsRoots and their rhizosphere considerably influence soil structure by regulating soil aggregate formation and stabilization. This study aimed to examine the rhizosphere effects on soil aggregation and explore potential mechanisms along secondary forest successions.MethodsEffects of roots and their rhizosphere on soil aggregation in two subtropical secondary forest successions were examined by separating soils into rhizosphere and bulk soils. Soil aggregate mean weight diameter (MWD), soil organic carbon (SOC), soil nutrients, and fine-root traits were simultaneously measured.ResultsSoil aggregate MWD increased significantly in the bulk soils along secondary forest successions, but did not differ in the rhizosphere soils. Rhizosphere effects on soil aggregate MWD (i.e., root-induced differences between the rhizosphere and bulk soils) were thus significantly higher at the early-successional stage of subtropical forest with low soil fertility than those at the late stages with high fertility. Rhizosphere significantly increased SOC and soil total nitrogen (TN) throughout the entire secondary forest successions, which was nonlinearly correlated with soil aggregate MWD. Principal components regression analysis showed that SOC was the primary abiotic factor and positively correlated with soil aggregate MWD. As for biotic factors, fine-root length density and N concentration were two important root traits having significant effects on soil aggregate stability. An improved conceptual framework was developed to advance our understanding of soil aggregation and rhizosphere effects, highlighting the roles of soil fertility (i.e., SOC and available nutrients), root traits, and forest age in driving soil aggregation.ConclusionsImpacts of root-derived organic compounds inputs to rhizosphere on soil aggregation were stronger at the early-successional stage of subtropical forest than those at the late stages. This succession-specific pattern in rhizosphere effects largely resulted from the nonlinear relationships between soil aggregate MWD and SOC concentration with a plateau at high SOC. Incorporating the SOC-dependent rhizosphere effects on biogeochemical cycle into Earth system models might improve the prediction of forest soil C dynamics.

引用

页码：365 / 380

页数：16

共 66 条

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