Grassland root functional parameters vary according to a community‐level resource acquisition–conservation trade‐off

Journal of Vegetation Science - Tập 27 Số 4 - Trang 749-758 - 2016
Florian Fort1, Pablo Cruz2, Eric Lecloux2, Claire Jouany3, Ciprian Stroïa4, Jean‐Pierre Theau2, Claire Jouany2
1Montpellier SupAgro UMR 5175 CEFE Université de Montpellier – Université Paul Valéry – EPHE 1919 route de Mende F‐34293 Montpellier Cedex 5 France
2INRA UMR1248 AGIR INRA – Université de Toulouse – INPT F‐31326 Castanet‐Tolosan France
3Animal Sciences Department Ecological Natural Grassland Research Group Universidade Federal de Santa Maria Santa Maria 97150‐900 Brazil
4Department of Biology and Plant Protection Banat University of Agricultural Sciences and Veterinary Medicine “King Michael I of Romania” Timisoara Calea Aradului 119 300645 Timisoara Romania

Tóm tắt

AbstractQuestionsThe fundamental trade‐off between fine root trait attributes related to resource acquisition and conservation is well documented at species and community levels. However, relations remain unclear between this trade‐off and community adaptation to environmental factors. As a result we ask: (1) how do fertility changes influence community position along the root acquisition–conservation trade‐off; (2) how does root position along the soil profile influence its functional parameter; and (3) do fertility and soil depth have an interactive effect on community root parameters?LocationNative multi‐species temperate grassland in the French Massif Central.MethodsWe assessed botanical composition and measured community root functional parameters (at plot and soil layer levels) in 16 plots differentiated by the amounts of N and P fertilizers applied over 16 yr and a soil depth gradient. Structural equation models were used to analyse relations among environmental factors, botanical composition and root functional parameters.ResultsBotanical composition and plot‐level root functional parameters vary according to fertility and soil depth. Communities from low fertility plots display a resource conservation strategy, i.e. high root tissue density, low specific root length (SRL) and low root length density (RLD), while communities from high fertility plots display a resource acquisition strategy, i.e. opposite parameter values. This demonstrates the importance of root resource management strategies in community adaptation to resource acquisition. Roots display different parameter values with soil depth. Roots in the surface horizon have small diameters and high SRL and RLD, suggesting intensive soil exploration and a high nutrient acquisition capacity. Roots in deep horizons have large diameters and low SRL, suggesting high water transport capacity per root length unit. This pattern is affected by plot fertility, i.e. communities from high fertility plots show higher root strategy differentiation with depth than communities from low fertility plots. We hypothesize that this root specialization along the soil profile enables species to be competitive for nutrient uptake in shallow soil layers and water uptake and transport in deep soil layers.ConclusionOur study provides evidence that fertility and soil depth modified root functional parameters, in agreement with predictions from the economics spectrum theory.

Từ khóa


Tài liệu tham khảo

10.1016/j.tree.2014.10.006

10.1086/285524

10.1007/s11104-006-9002-x

10.1034/j.1600-0706.2001.930210.x

Vries D.M., 1959, Methods used in botanical grassland research in the Netherlands and their application, Herbage Abstracts, 27, 1

Ellenberg H., 1991, Zeigerwerte von Pflanzen in Mitteleuropa, Scripta Geobotanica, 18, 9

10.1111/1365-2435.12217

10.1016/j.envexpbot.2014.09.007

10.1016/B978-0-12-417104-6.00008-X

10.1046/j.0022-0477.2001.00609.x

Grime J.P., 1988, Comparative plant ecology. A functional approach to common British species

10.1007/s11258-009-9668-2

10.1093/jxb/eri280

10.1007/s11104-009-9929-9

10.1016/j.eja.2004.06.001

10.1111/j.1365-2435.2007.01339.x

10.1007/s11104-013-1836-4

10.1111/j.0030-1299.2004.13250.x

10.1111/j.1654-1103.2005.tb02350.x

10.1023/A:1015822003011

10.1111/j.1469-8137.2012.04198.x

10.1007/s11104-011-0752-8

Olsen S.R., 1954, Estimation of available phosphorus in soils by extraction with sodium bicarbonate

10.1111/1365-2745.12000

10.1111/1365-2745.12351

10.18637/jss.v048.i02

10.1016/j.agee.2006.06.007

10.1016/0003-2697(87)90649-X

10.1890/05-0822

10.1016/j.tree.2006.02.004

10.1890/0012-9615(2006)076[0381:COSALS]2.0.CO;2

Thông tin
Thông tin xuất bản

Journal of Vegetation Science

Tập 27 Số 4

749-758

Thông tin tác giả