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Abreu RCR, Durigan G, Melo ACG, Pilon NAL, Hoffmann WA. Facilitation by isolated trees triggers woody encroachment and a biome shift at the savanna–forest transition. J Appl Ecol 2021. [DOI: 10.1111/1365-2664.13994] [Citation(s) in RCA: 6] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Affiliation(s)
- Rodolfo C. R. Abreu
- Department of Plant and Microbial Biology North Carolina State University (NCSU) Raleigh NC USA
| | - Giselda Durigan
- Laboratório de Ecologia e Hidrologia Florestal Floresta Estadual de Assis Instituto Florestal São Paulo Brazil
- Instituto de Biologia Universidade Estadual de Campinas (UNICAMP) São Paulo Brazil
| | - Antônio C. G. Melo
- Laboratório de Ecologia e Hidrologia Florestal Floresta Estadual de Assis Instituto Florestal São Paulo Brazil
| | - Natashi A. L. Pilon
- Instituto de Biologia Universidade Estadual de Campinas (UNICAMP) São Paulo Brazil
| | - William A. Hoffmann
- Department of Plant and Microbial Biology North Carolina State University (NCSU) Raleigh NC USA
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Jamison‐Daniels S, Kissling WD, Botha M, Harris MA, Gordon CE, Greve M. The role of deterministic succession during forest development within a southern African savanna. Biotropica 2021. [DOI: 10.1111/btp.12890] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Affiliation(s)
| | - W. Daniel Kissling
- Institute for Biodiversity and Ecosystem Dynamics University of Amsterdam Amsterdam The Netherlands
| | - Monique Botha
- Department of Plant and Soil Sciences University of Pretoria Pretoria South Africa
- School of Animal, Plant and Environmental Sciences University of the Witwatersrand Johannesburg South Africa
| | - Mathew A. Harris
- Department of Plant and Soil Sciences University of Pretoria Pretoria South Africa
- FABI (Forestry and Agricultural Biotechnology Institute) University of Pretoria Pretoria South Africa
| | - Christopher E. Gordon
- Centre for Biodiversity Dynamics in a Changing World Aarhus University Aarhus C Denmark
| | - Michelle Greve
- Department of Plant and Soil Sciences University of Pretoria Pretoria South Africa
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Montesinos-Navarro A, Verdú M, Querejeta JI, Valiente-Banuet A. Nurse plants transfer more nitrogen to distantly related species. Ecology 2017; 98:1300-1310. [DOI: 10.1002/ecy.1771] [Citation(s) in RCA: 24] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 01/20/2017] [Accepted: 01/30/2017] [Indexed: 11/07/2022]
Affiliation(s)
- Alicia Montesinos-Navarro
- Departamento de Ecología de la Biodiversidad; Instituto de Ecología; Universidad Nacional Autónoma de México; A.P. 70-275 C.P. 04510 México D.F México
- Centro de Investigaciones sobre Desertificación (CIDE, CSIC-UV-GV); Carretera de Moncada-Náquera Km 4.5 46113 Moncada Valencia Spain
| | - Miguel Verdú
- Centro de Investigaciones sobre Desertificación (CIDE, CSIC-UV-GV); Carretera de Moncada-Náquera Km 4.5 46113 Moncada Valencia Spain
| | - José Ignacio Querejeta
- Departamento de Conservación de Suelos y Aguas; Centro de Edafología y Biología Aplicada del Segura (CEBAS-CSIC); Campus de Espinardo, PO Box 4195 E-30100 Murcia Spain
| | - Alfonso Valiente-Banuet
- Departamento de Ecología de la Biodiversidad; Instituto de Ecología; Universidad Nacional Autónoma de México; A.P. 70-275 C.P. 04510 México D.F México
- Centro de Ciencias de la Complejidad; Universidad Nacional Autónoma de México; Ciudad Universitaria 04510 México D.F México
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Montesinos-Navarro A, Segarra-Moragues JG, Valiente-Banuet A, Verdú M. Evidence for phylogenetic correlation of plant-AMF assemblages? ANNALS OF BOTANY 2015; 115:171-7. [PMID: 25452252 PMCID: PMC4551090 DOI: 10.1093/aob/mcu228] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/26/2014] [Revised: 09/10/2014] [Accepted: 10/09/2014] [Indexed: 05/23/2023]
Abstract
BACKGROUND AND AIMS Specificity in biotic interactions is mediated' by functional traits inducing shifts in the community species composition. Functional traits are often evolutionarily conserved, resulting in closely related species tending to interact with similar species. This tendency may initially shape the phylogenetic composition of coexisting guilds, but other intraguild ecological processes may either blur or promote the mirroring of the phylogenetic compositions between guilds. The roles of intra- and interguild interactions in shaping the phylogenetic community composition are largely unknown, beyond the mere selectivity in the interguild interactions. Plant facilitation is a phylogenetically structured species-specific process involving interactions not only between the same guild of plants, but also between plants and other guilds such as arbuscular mycorrhizal fungi (AMF). In this study it is hypothesized that reciprocal plant-AMF interactions will leave an interdependent phylogenetic signal in the community composition of both plants and AMF. METHODS A correlation was used to test for a relationship between the phylogenetic composition of plant and AMF assemblages in a patchy xeric shrubland environment shaped by plant facilitation. In addition, a null model was used to test whether this correlation can be solely explained by selectivity in plant-AMF interactions. KEY RESULTS A significant correlation was observed between the phylogenetic composition of plant and AMF assemblages. Plant phylogenetic composition in a patch was related to the predominance of plant species with high nursery quality that can influence the community assembly. AMF phylogenetic composition was related to the AMF phylogenetic diversity in each patch. CONCLUSIONS This study shows that shifts in the phylogenetic composition of plants and AMF assemblages do not occur independently. It is suggested that besides selectivity in plant-AMF interactions, inter-related succession dynamics of plants and AMF within patches could be an ecological mechanism driving community assembly. Future lines of research might explore whether interlinked above- and below-ground dynamics could be occurring across multiple guilds simultaneously.
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Affiliation(s)
- A Montesinos-Navarro
- Centro de Investigaciones sobre Desertificación (CIDE, CSIC-UV-GV), Carretera de Moncada-Náquera Km 4.5 46113 Moncada, Valencia Spain, Departamento de Ecología de la Biodiversidad, Instituto de Ecología, Universidad Nacional Autónoma de México, AP 70-275, CP 04510, México, DF, México and Centro de Ciencias de la Complejidad, Ciudad Universitaria, Universidad Nacional Autónoma de México, 04510, DF, México Centro de Investigaciones sobre Desertificación (CIDE, CSIC-UV-GV), Carretera de Moncada-Náquera Km 4.5 46113 Moncada, Valencia Spain, Departamento de Ecología de la Biodiversidad, Instituto de Ecología, Universidad Nacional Autónoma de México, AP 70-275, CP 04510, México, DF, México and Centro de Ciencias de la Complejidad, Ciudad Universitaria, Universidad Nacional Autónoma de México, 04510, DF, México
| | - J G Segarra-Moragues
- Centro de Investigaciones sobre Desertificación (CIDE, CSIC-UV-GV), Carretera de Moncada-Náquera Km 4.5 46113 Moncada, Valencia Spain, Departamento de Ecología de la Biodiversidad, Instituto de Ecología, Universidad Nacional Autónoma de México, AP 70-275, CP 04510, México, DF, México and Centro de Ciencias de la Complejidad, Ciudad Universitaria, Universidad Nacional Autónoma de México, 04510, DF, México
| | - A Valiente-Banuet
- Centro de Investigaciones sobre Desertificación (CIDE, CSIC-UV-GV), Carretera de Moncada-Náquera Km 4.5 46113 Moncada, Valencia Spain, Departamento de Ecología de la Biodiversidad, Instituto de Ecología, Universidad Nacional Autónoma de México, AP 70-275, CP 04510, México, DF, México and Centro de Ciencias de la Complejidad, Ciudad Universitaria, Universidad Nacional Autónoma de México, 04510, DF, México Centro de Investigaciones sobre Desertificación (CIDE, CSIC-UV-GV), Carretera de Moncada-Náquera Km 4.5 46113 Moncada, Valencia Spain, Departamento de Ecología de la Biodiversidad, Instituto de Ecología, Universidad Nacional Autónoma de México, AP 70-275, CP 04510, México, DF, México and Centro de Ciencias de la Complejidad, Ciudad Universitaria, Universidad Nacional Autónoma de México, 04510, DF, México
| | - M Verdú
- Centro de Investigaciones sobre Desertificación (CIDE, CSIC-UV-GV), Carretera de Moncada-Náquera Km 4.5 46113 Moncada, Valencia Spain, Departamento de Ecología de la Biodiversidad, Instituto de Ecología, Universidad Nacional Autónoma de México, AP 70-275, CP 04510, México, DF, México and Centro de Ciencias de la Complejidad, Ciudad Universitaria, Universidad Nacional Autónoma de México, 04510, DF, México
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Bowman AS, Facelli JM, Sinclair R. Long-term influence of fallen logs on patch formation and their effects under contrasting grazing regimes. AUSTRAL ECOL 2014. [DOI: 10.1111/aec.12204] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Affiliation(s)
- Alexandra S. Bowman
- Ecology, Evolution and Landscape Science; School of Earth and Environmental Sciences; The University of Adelaide; Adelaide South Australia 5005 Australia
| | - José M. Facelli
- Ecology, Evolution and Landscape Science; School of Earth and Environmental Sciences; The University of Adelaide; Adelaide South Australia 5005 Australia
| | - Russell Sinclair
- Ecology, Evolution and Landscape Science; School of Earth and Environmental Sciences; The University of Adelaide; Adelaide South Australia 5005 Australia
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Liu F, Archer SR, Gelwick F, Bai E, Boutton TW, Wu XB. Woody plant encroachment into grasslands: spatial patterns of functional group distribution and community development. PLoS One 2013; 8:e84364. [PMID: 24367655 PMCID: PMC3867480 DOI: 10.1371/journal.pone.0084364] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/26/2013] [Accepted: 11/21/2013] [Indexed: 11/18/2022] Open
Abstract
Woody plant encroachment into grasslands has been globally widespread. The woody species invading grasslands represent a variety of contrasting plant functional groups and growth forms. Are some woody plant functional types (PFTs) better suited to invade grasslands than others? To what extent do local patterns of distribution and abundance of woody PFTs invading grasslands reflect intrinsic topoedaphic properties versus plant-induced changes in soil properties? We addressed these questions in the Southern Great Plains, United States at a subtropical grassland known to have been encroached upon by woody species over the past 50-100 years. A total of 20 woody species (9 tree-statured; 11 shrub-statured) were encountered along a transect extending from an upland into a playa basin. About half of the encroaching woody plants were potential N2-fixers (55% of species), but they contributed only 7% to 16 % of the total basal area. Most species and the PFTs they represent were ubiquitously distributed along the topoedaphic gradient, but with varying abundances. Overstory-understory comparisons suggest that while future species composition of these woody communities is likely to change, PFT composition is not. Canonical correspondence analysis (CCA) ordination and variance partitioning (Partial CCA) indicated that woody species and PFT composition in developing woody communities was primarily influenced by intrinsic landscape location variables (e.g., soil texture) and secondarily by plant-induced changes in soil organic carbon and total nitrogen content. The ubiquitous distribution of species and PFTs suggests that woody plants are generally well-suited to a broad range of grassland topoedaphic settings. However, here we only examined categorical and non-quantitative functional traits. Although intrinsic soil properties exerted more control over the floristics of grassland-to-woodland succession did plant modifications of soil carbon and nitrogen concentrations, the latter are likely to influence productivity and nutrient cycling and may, over longer time-frames, feed back to influence PFT distributions.
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Affiliation(s)
- Feng Liu
- Key Laboratory of Aquatic Botany and Watershed Ecology, Wuhan Botanical Garden, Chinese Academy of Sciences, Wuhan, China
- Department of Ecosystem Science and Management, Texas A&M University, College Station, Texas, United States of America
- * E-mail:
| | - Steven R. Archer
- School of Natural Resources and the Environment, University of Arizona, Tucson, Arizona, United States of America
| | - Frances Gelwick
- Department of Wildlife and Fisheries Sciences, Texas A&M University, College Station, Texas, United States of America
| | - Edith Bai
- State Key Laboratory of Forest and Soil Ecology, Institute of Applied Ecology, Chinese Academy of Sciences, Shenyang, China
| | - Thomas W. Boutton
- Department of Ecosystem Science and Management, Texas A&M University, College Station, Texas, United States of America
| | - Xinyuan Ben Wu
- Department of Ecosystem Science and Management, Texas A&M University, College Station, Texas, United States of America
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Abstract
An analysis was made of the floristic composition of 45 savanna sites located throughout the southern neoarctic and neotropics. A total of 533 woody species were recorded from published and reliable unpublished floristic lists; of these, 234 species (44%) were from 10 Brazilian cerrado sites, with 187 (80%) of them restricted to the cerrado biome. The cerrados were clearly shown to be the most diverse New World savanna system with a high degree of endemism. The data were analysed using two multivariate techniques: TWINSPAN and DCA. Four phytogeographic zones were identified: Central Brazil and Bolivia extending to Southern Amazonia; north of Amazonia extending across the isthmus of Central America and including the Caribbean; Belize, Guatemala and Southern Mexico; and north of the Mexican Plateau. The analyses revealed gradients of floristic variation associated with latitude and longitude, and showed the great heterogeneity of savanna vegetation.
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Filotas E, Grant M, Parrott L, Rikvold PA. The effect of positive interactions on community structure in a multi-species metacommunity model along an environmental gradient. Ecol Modell 2010. [DOI: 10.1016/j.ecolmodel.2009.12.005] [Citation(s) in RCA: 32] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/16/2022]
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Bai E, Boutton TW, Liu F, Wu XB, Archer SR. Variation in woody plant delta(13)C along a topoedaphic gradient in a subtropical savanna parkland. Oecologia 2008; 156:479-89. [PMID: 18327619 DOI: 10.1007/s00442-008-1003-4] [Citation(s) in RCA: 28] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/05/2007] [Accepted: 02/07/2008] [Indexed: 10/22/2022]
Abstract
delta(13)C values of C(3) plants are indicators of plant carbon-water relations that integrate plant responses to environmental conditions. However, few studies have quantified spatial variation in plant delta(13)C at the landscape scale. We determined variation in leaf delta(13)C, leaf nitrogen per leaf area (N(area)), and specific leaf area (SLA) in April and August 2005 for all individuals of three common woody species within a 308 x 12-m belt transect spanning an upland-lowland topoedaphic gradient in a subtropical savanna in southern Texas. Clay content, available soil moisture, and soil total N were all negatively correlated with elevation. The delta(13)C values of Prosopis glandulosa (deciduous N(2)-fixing tree legume), Condalia hookeri (evergreen shrub), and Zanthoxylum fagara (evergreen shrub) leaves increased 1-4 per thousand with decreasing elevation, with the delta(13)C value of P. glandulosa leaves being 1-3 per thousand higher than those of the two shrub species. Contrary to theory and results from previous studies, delta(13)C values were highest where soil water was most available, suggesting that some other variable was overriding or interacting with water availability. Leaf N(area) was positively correlated with leaf delta(13)C of all species (p < 0.01) and appeared to exert the strongest control over delta(13)C along this topoedaphic gradient. Since leaf N(area) is positively related to photosynthetic capacity, plants with high leaf N(area) are likely to have low p (I)/p (a) ratios and therefore higher delta(13)C values, assuming stomatal conductance is constant. Specific leaf area was not correlated significantly with leaf delta(13)C. Following a progressive growing season drought in July/August, leaf delta(13)C decreased. The lower delta(13)C in August may reflect the accumulation of (13)C-depleted epicuticular leaf wax. We suggest control of leaf delta(13)C along this topoedaphic gradient is mediated by leaf N(area) rather than by stomatal conductance limitations associated with water availability.
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Affiliation(s)
- Edith Bai
- Department of Ecosystem Science and Management, Texas A&M University, College Station, TX 77843-2138, USA.
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Population Ecology of Hybrid Mesquite (Prosopis Species) in Western Australia: How Does it Differ from Native Range Invasions and What are the Implications for Impacts and Management? Biol Invasions 2006. [DOI: 10.1007/s10530-005-3427-7] [Citation(s) in RCA: 36] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/01/2022]
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Zou CB, Barnes PW, Archer S, McMurtry CR. Soil moisture redistribution as a mechanism of facilitation in savanna tree-shrub clusters. Oecologia 2005; 145:32-40. [PMID: 15942764 DOI: 10.1007/s00442-005-0110-8] [Citation(s) in RCA: 84] [Impact Index Per Article: 4.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/24/2004] [Accepted: 03/24/2005] [Indexed: 10/25/2022]
Abstract
Plant-soil water relations were examined in the context of a selective removal study conducted in tree-shrub communities occupying different but contiguous soil types (small discrete clusters on shallow, duplex soils versus larger, extensive groves on deep, sandy soils) in a subtropical savanna parkland. We (1) tested for the occurrence of soil moisture redistribution by hydraulic lift (HL), (2) determined the influence of edaphic factors on HL, and (3) evaluated the significance of HL for overstory tree-understory shrub interactions. Diel cycling and nocturnal increases in soil water potential (Psisoil), characteristic signatures of HL, occurred intermittently throughout an annual growth cycle in both communities over a range of moisture levels (Psisoil=-0.5 to -6.0 MPa) but only when soils were distinctly stratified with depth (dry surface/wet deep soil layers). The magnitude of mean (+/-SE) diel fluctuations in Psisoil (0.19+/-0.01 MPa) did not differ on the two community types, though HL occurred more frequently in groves (deep soils) than clusters (shallow soils). Selective removal of either Prosopis glandulosa overstory or mixed-species shrub understory reduced the frequency of HL, indicating that Prosopis and at least one other woody species was conducting HL. For Zanthoxylum fagara, a shallow-rooted understory shrub, Prosopis removal from clusters decreased leaf water potential (Psileaf) and net CO2 exchange (A) during periods of HL. In contrast, overstory removal had neutral to positive effects on more deeply-rooted shrub species (Berberis trifoliolata and Condalia hookeri). Removal of the shrub understory in groves increased A in the overstory Prosopis. Results indicate the following: (a) HL is common but temporally dynamic in these savanna tree-shrub communities; (b) edaphic factors influencing the degree of overstory/understory development, rooting patterns and soil moisture distribution influence HL; (c) net interactions between overstory and understory elements in these woody patches can be positive, negative and neutral over an annual cycle, and (d) Prosopis-mediated HL is an important mechanism of faciliation for some, but not all, understory shrubs.
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Affiliation(s)
- C B Zou
- Department of Rangeland Ecology and Management, Texas A&M University, College Station, TX, 77843-2126, USA
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PHILLIPS PATRICIAL, BARNES PAULW. Spatial Asymmetry in Tree-shrub Clusters in a Subtropical Savanna. AMERICAN MIDLAND NATURALIST 2003. [DOI: 10.1674/0003-0031(2003)149[0059:saitsc]2.0.co;2] [Citation(s) in RCA: 12] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/19/2022]
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Boutton TW, Archer SR, Midwood AJ. Stable isotopes in ecosystem science: structure, function and dynamics of a subtropical Savanna. RAPID COMMUNICATIONS IN MASS SPECTROMETRY : RCM 1999; 13:1263-1277. [PMID: 10407309 DOI: 10.1002/(sici)1097-0231(19990715)13:13<1263::aid-rcm653>3.0.co;2-j] [Citation(s) in RCA: 32] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/23/2023]
Abstract
Stable isotopes are often utilized as intrinsic tracers to study the effects of human land uses on the structural and functional characteristics of ecosystems. Here, we illustrate how stable isotopes of H, C, and O have been utilized to document changes in ecosystem structure and function using a case study from a subtropical savanna ecosystem. Specifically, we demonstrate that: (1) delta 13C values of soil organic carbon record a vegetation change in this ecosystem from C4 grassland to C3 woodland during the past 40-120 years, and (2) delta 2H and delta 18O of plant and soil water reveal changes in ecosystem hydrology that accompanied this grassland-to-woodland transition. In the Rio Grande Plains of North America, delta 13C values of plants and soils indicate that areas now dominated by C3 subtropical thorn woodland were once C4 grasslands. delta 13C values of current organic matter inputs from wooded landscape elements in this region are characteristic of C3 plants (-28 to -25/1000), while those of the associated soil organic carbon are higher and range from -20 to -15/1000. Approximately 50-90% of soil carbon beneath the present C3 woodlands is derived from C4 grasses. A strong memory of the C4 grasslands that once dominated this region is retained by delta 13C values of organic carbon associated with fine and coarse clay fractions. When delta 13C values are evaluated in conjunction with 14C measurements of that same soil carbon, it appears that grassland-to-woodland conversion occurred largely within the past 40-120 years, coincident with the intensification of livestock grazing and reductions in fire frequency. These conclusions substantiate those based on demographic characteristics of the dominant tree species, historical aerial photography, and accounts of early settlers and explores. Concurrent changes in soil delta 13C values and organic carbon content over the past 90 years also indicate that wooded landscape elements are behaving as sinks for atmospheric CO2 by sequestering carbon derived from both the previous C4 grassland and the present C3 woody vegetation. Present day woodlands have hydrologic characteristics fundamentally different from those of the original grasslands. Compared to plants in remnant grasslands, tree and shrub species in the woodlands are rooted more deeply and have significantly greater root biomass and density than grasslands. delta 18O and delta 2H values of plant and soil water confirm that grassland species acquire soil water primarily from the upper 0.5 m of the soil profile. In contrast, trees and shrubs utilize soil water from throughout the upper 4 m of the profile. Thus, soil water that formerly may have infiltrated beyond the reach of the grassland roots and contributed to local groundwater recharge or other hydrologic fluxes may now be captured and transpired by the recently formed woodland plant communities. The natural abundances of stable isotopes revealed fundamental information regarding the impacts of human land use activities on the structure and function of this subtropical savanna. Stable isotopes provided direct, spatially explicit evidence for dramatic changes in ecosystem physiognomy and demonstrated some functional consequences for the hydrologic cycle. Furthermore, grassland-to-woodland conversion has been geographically extensive in the worlds' drylands, suggesting that these ecosystem-level changes in vegetation structure, carbon cycling, and hydrology may have implications for regional/global biogeochemistry and climate.
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Affiliation(s)
- T W Boutton
- Department of Rangeland Ecology and Management, Texas A&M University, College Station 77843-2126, USA.
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