气候变化领域集成服务门户(CCPortal): Persistent anthropogenic legacies structure depth dependence of regenerating rooting systems and their functions

CCPortal

DOI	10.1007/s10533-020-00641-2
	Persistent anthropogenic legacies structure depth dependence of regenerating rooting systems and their functions
	Hauser E.; Richter D.D.; Markewitz D.; Brecheisen Z.; Billings S.A.
发表日期	2020
ISSN	1682563
卷号	147 期号:3
英文摘要	Biotically-mediated weathering helps to shape Earth’s surface. For example, plants expend carbon (C) to mobilize nutrients in forms whose relative abundances vary with depth. It thus is likely that trees’ nutrient acquisition strategies—their investment in rooting systems and exudates—may function differently following disturbance-induced changes in depth of rooting zones and soil nutrient stocks. These changes may persist across centuries. We test the hypothesis that plant C allocation for nutrient acquisition is depth dependent as a function of rooting system development and relative abundances of organic vs. mineral nutrient stocks. We further posit that patterns of belowground C allocation to nutrient acquisition reveal anthropogenic signatures through many decades of forest regeneration. To test this idea, we examined fine root abundances and rooting system C in organic acid exudates and exo-enzymes in tandem with depth distributions of organically- and mineral-bound P stocks. Our design permitted us to estimate C tradeoffs between organic vs. mineral nutrient benefits in paired forests with many similar aboveground traits but different ages: post-agricultural mixed-pine forests and older reference hardwoods. Fine roots were more abundant throughout the upper 2 m in reference forest soils than in regenerating stands. Rooting systems in all forests exhibited depth-dependent C allocations to nutrient acquisition reflecting relative abundances of organic vs. mineral bound P stocks. Further, organic vs. mineral stocks underwent redistribution with historic land use, producing distinct ecosystem nutritional economies. In reference forests, rooting systems are allocating C to relatively deep fine roots and low-C exudation strategies that can increase mobility of mineral-bound P stocks. Regenerating forests exhibit relatively shallower fine root distributions and more diverse exudation strategies reflecting more variable nutrient stocks. We observed these disparities in rooting systems’ depth and nutritional mechanisms even though the regenerating forests have attained aboveground biomass stocks similar to those in reference hardwood forests. These distinctions offer plausible belowground mechanisms for observations of continued C sink strength in relatively old forests, and have implications for soil C fates and soil development on timescales relevant to human lifetimes. As such, depth-dependent nutrient returns on plant C investments represent a subtle but consequential signal of the Anthropocene. © 2020, Springer Nature Switzerland AG.
英文关键词	Anthropocene; Carbon allocation; Forest regeneration; Mineral-bound phosphorus; Root exudates; Soil organic matter
学科领域	aboveground biomass; anthropogenic effect; biomass allocation; dietary mineral; exudation; fine root; forest ecosystem; mobility; organic acid; organisms by inadvertent anthropogenic effect; phosphorus; root system; rooting; soil nutrient; soil organic matter
语种	英语
scopus关键词	aboveground biomass; anthropogenic effect; biomass allocation; dietary mineral; exudation; fine root; forest ecosystem; mobility; organic acid; organisms by inadvertent anthropogenic effect; phosphorus; root system; rooting; soil nutrient; soil organic matter
来源期刊	Biogeochemistry
文献类型	期刊论文
条目标识符	http://gcip.llas.ac.cn/handle/2XKMVOVA/120381
作者单位	Department of Ecology and Evolutionary Biology, Kansas Biological Survey and the University of Kansas, Lawrence, KS 66047, United States; Nicholas School of the Environment, Duke University, Durham, NC 27708, United States; Warnell School of Forestry and Natural Resources, The University of Georgia, Athens, GA 30602, United States; Department of Agronomy, Purdue University, West Lafayette, IN 47907, United States
推荐引用方式 GB/T 7714	Hauser E.,Richter D.D.,Markewitz D.,et al. Persistent anthropogenic legacies structure depth dependence of regenerating rooting systems and their functions[J],2020,147(3).
APA	Hauser E.,Richter D.D.,Markewitz D.,Brecheisen Z.,&Billings S.A..(2020).Persistent anthropogenic legacies structure depth dependence of regenerating rooting systems and their functions.Biogeochemistry,147(3).
MLA	Hauser E.,et al."Persistent anthropogenic legacies structure depth dependence of regenerating rooting systems and their functions".Biogeochemistry 147.3(2020).