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Abstract
A plant functional trait study was conducted to know the existing relationship between important leaf traits namely, specific leaf area (SLA), leaf dry matter content (LDMC), and leaf life span (LL) in tropical dry evergreen forest (TDEFs) of Peninsular India. Widely accepted methodologies were employed to record functional traits. The relationships between SLA and LDMC, LDMC and LL, and SLA and LL were measured. Pearson’s coefficient of correlation showed a significant negative relationship between SLA and LDMC, and SLA and LL, whereas a significant positive relationship was prevailed between LDMC and LL. The mean trait values (SLA, LDMC, and LL) of evergreens varied significantly from deciduous species. SLA had a closer relationship with LDMC than LL. Similarly, LL had a closer relationship with SLA than LDMC. Species with evergreen leaf habits dominated forest sites under study. Evergreen species dominate the study area with a high evergreen-deciduous ratio of 5.34:1. The S strategy score of trees indicated a relatively higher biomass allocation to persistent tissues. TDEFs occur in low elevation, semiarid environment, but with the combination of oligotrophic habitat, high temperature and longer dry season these forests were flourishing as a unique evergreen ecosystem in the drier environment. The relationships found between leaf traits were in concurrence with earlier findings. Trees of TDEFs survive on the poor-nutrient habitat with a low SLA, high LDMC, and LL. This study adds baseline data on key leaf traits to plant functional trait database of India.
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Ruttan A, Lortie CJ, Haas SM. Shrubs as magnets for pollination: A test of facilitation and reciprocity in a shrub-annual facilitation system. CURRENT RESEARCH IN INSECT SCIENCE 2021; 1:100008. [PMID: 36003594 PMCID: PMC9387484 DOI: 10.1016/j.cris.2021.100008] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 09/02/2020] [Revised: 01/04/2021] [Accepted: 01/05/2021] [Indexed: 11/22/2022]
Abstract
Insect-pollinated shrub Larrea tridentata increases the pollinator visitation to annuals. The effect of Larrea tridentata on pollinator visitation is inconsistent between years. Wind-pollinated shrub Ambrosia dumosa reduces the visitation duration of flies to annuals. Surrounding annuals reduce the visitation duration of pollinators to the shrub Larrea tridentata.
The magnet species hypothesis proposes that flowering plants that are attractive to pollinators can increase the relative pollination rates of neighbouring plants by acting as ‘magnets.’ Here, we test the hypothesis that insect-pollinated shrub species Larrea tridentata and wind-pollinated shrub species Ambrosia dumosa act as magnets for the pollinator visitation of understory annual plant species in an arid ecosystem. As an extension to the magnet species hypothesis, we propose the double magnet species hypothesis in which we further test for reciprocity by the floral island created in the understory of the benefactor shrubs as an additional pollinator magnet for the shrub itself. We used an annual plant placed near each shrub and the open to measure the effect of shrubs on annuals. The double magnet species hypothesis was tested using L. tridentata with and without surrounding annuals. We measured pollinator visitation and visit duration using video and in-situ observation techniques to test whether shrubs increase pollinator visitation to understory annual plants, if insect-pollinated shrubs act as better pollinator magnets than wind-pollinated shrubs (to determine the effects of the floral resource itself), and whether shrubs with annuals in their understory have higher pollinator visitation rates relative to shrubs without annuals. We found that insect-pollinated shrubs increased the visitation rate and duration of visits by pollinators to their understory plants and that wind-pollinated shrubs decreased the duration of visits of some insect visitors, but these relationships varied between years. While the presence of annuals did not change the visitation rate of all possible pollinators to L. tridentata flowers, they did decrease the visitation duration of specifically bees, indicating a negative reciprocal effect of the understory on pollination. Thus, the concentrated floral resources of flowers on insect-pollinated shrubs can act as a magnet that attract pollinators but that in turn provide a cost to pollination of the shrub. However, while wind-pollinated shrubs may provide other benefits, they may provide a cost to the pollination of their understory. These findings support the magnet species hypothesis as an additional mechanism of facilitation by insect-pollinated shrubs to other plant species within arid ecosystems.
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Yukawa J, Yamamura K, Fujimoto K, Tokuda M, Muroya S, Maki T, Sadoshima T, Fukuda T. Key-factors and key-stages that determine the leaf longevity of an evergreen broad-leaved tree, Neolitsea sericea (Lauraceae) at different growing sites in southern Japan. Ecol Res 2017. [DOI: 10.1007/s11284-017-1525-5] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
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She W, Zhang Y, Qin S, Wu B, Bai Y. Increased Precipitation and Nitrogen Alter Shrub Architecture in a Desert Shrubland: Implications for Primary Production. FRONTIERS IN PLANT SCIENCE 2016; 7:1908. [PMID: 28066468 PMCID: PMC5167761 DOI: 10.3389/fpls.2016.01908] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/11/2016] [Accepted: 12/01/2016] [Indexed: 06/02/2023]
Abstract
Shrublands are one of the major types of ecosystems in the desert regions of northern China, which is expected to be substantially more sensitive to global environmental changes, such as widespread nitrogen enrichment and precipitation changes, than other ecosystem types. However, the interactive effects of nitrogen and precipitation on them remain poorly understood. We conducted a fully factorial field experiment simulating three levels of precipitation (ambient, +20%, +40%) and with two levels of nitrogen deposition (ambient, 60 kg N ha-1 yr-1) in a desert shrubland in the Mu Us Desert of northern China. We used plant architectural traits (plant cover, volume, twig size and number) as proxies to predict aboveground net primary productivity (ANPP) of the dominant shrub (Artemisia ordosica Krasch), and assessed the responses of plant productivity and architectural traits to water and nitrogen addition. We found significant differences in twig size and number of A. ordosica under water and nitrogen treatments but not in shrub cover/volume, which suggest that twig size and number of the shrub species were more sensitive to environmental changes. The productivity of the overall community was sensitive to increased precipitation and nitrogen, and shrubs played a more important role than herbaceous plants in driving productivity in this ecosystem. Precipitation- and nitrogen-induced increases in vegetation production were positively associated with increases in twig size and number of the dominant shrub. Water addition enhanced the twig length of A. ordosica, while nitrogen addition resulted in increased twig density (the number of twigs per square meter). Water and nitrogen interacted to affect twig length, but not twig number and shrub ANPP. The trade-off, defined as negative covariance between twig size and number, was likely the mechanism underlying the responses of twig length and shrub ANPP to water and nitrogen interactions. Our results highlight the sensitivity of twig size and number as indicators to estimate shrub production and the mechanism underpinning desert shrub ANPP response to global environmental changes.
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Affiliation(s)
- Weiwei She
- Yanchi Research Station, School of Soil and Water Conservation, Beijing Forestry UniversityBeijing, China
| | - Yuqing Zhang
- Yanchi Research Station, School of Soil and Water Conservation, Beijing Forestry UniversityBeijing, China
- Key Laboratory of State Forestry Administration on Soil and Water Conservation, Beijing Forestry UniversityBeijing, China
| | - Shugao Qin
- Yanchi Research Station, School of Soil and Water Conservation, Beijing Forestry UniversityBeijing, China
- Engineering Research Center of Forestry Ecological Engineering, Ministry of Education, Beijing Forestry UniversityBeijing, China
| | - Bin Wu
- Yanchi Research Station, School of Soil and Water Conservation, Beijing Forestry UniversityBeijing, China
- Key Laboratory of State Forestry Administration on Soil and Water Conservation, Beijing Forestry UniversityBeijing, China
| | - Yuxuan Bai
- Yanchi Research Station, School of Soil and Water Conservation, Beijing Forestry UniversityBeijing, China
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Limousin J, Yepez EA, McDowell NG, Pockman WT. Convergence in resource use efficiency across trees with differing hydraulic strategies in response to ecosystem precipitation manipulation. Funct Ecol 2015. [DOI: 10.1111/1365-2435.12426] [Citation(s) in RCA: 25] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Affiliation(s)
- Jean‐Marc Limousin
- Department of Biology MSC03 2020 1 University of New Mexico Albuquerque New Mexico 87131‐0001 USA
- Centre d'Ecologie Fonctionnelle et Evolutive CEFE UMR 5175 CNRS Université de Montpellier Université Paul‐Valéry EPHE 1919 route de Mende 34293 Montpellier 5 France
| | - Enrico A. Yepez
- Departamento de Ciencias del Agua y del Medio Ambiente Instituto Tecnologico de Sonora Ciudad Obregon Sonora 85000 Mexico
| | - Nate G. McDowell
- Earth and Environmental Sciences Division Los Alamos National Laboratory Los Alamos New Mexico 87545 USA
| | - William T. Pockman
- Department of Biology MSC03 2020 1 University of New Mexico Albuquerque New Mexico 87131‐0001 USA
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Westerband A, Dovčiak M, Quay-Velázquez GL, Medeiros JS. Aspect reduces soil moisture and tree cover, but not nitrogen mineralization or grass cover, in semiarid pinyon-juniper woodlands of the Southwestern United States. SOUTHWEST NAT 2015. [DOI: 10.1894/fmo-18.1] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022]
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Verlinden MS, Fichot R, Broeckx LS, Vanholme B, Boerjan W, Ceulemans R. Carbon isotope compositions (δ(13) C) of leaf, wood and holocellulose differ among genotypes of poplar and between previous land uses in a short-rotation biomass plantation. PLANT, CELL & ENVIRONMENT 2015; 38:144-156. [PMID: 24906162 DOI: 10.1111/pce.12383] [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: 10/29/2013] [Revised: 05/26/2014] [Accepted: 05/27/2014] [Indexed: 06/03/2023]
Abstract
The efficiency of water use to produce biomass is a key trait in designing sustainable bioenergy-devoted systems. We characterized variations in the carbon isotope composition (δ(13) C) of leaves, current year wood and holocellulose (as proxies for water use efficiency, WUE) among six poplar genotypes in a short-rotation plantation. Values of δ(13) Cwood and δ(13) Cholocellulose were tightly and positively correlated, but the offset varied significantly among genotypes (0.79-1.01‰). Leaf phenology was strongly correlated with δ(13) C, and genotypes with a longer growing season showed a higher WUE. In contrast, traits related to growth and carbon uptake were poorly linked to δ(13) C. Trees growing on former pasture with higher N-availability displayed higher δ(13) C as compared with trees growing on former cropland. The positive relationships between δ(13) Cleaf and leaf N suggested that spatial variations in WUE over the plantation were mainly driven by an N-related effect on photosynthetic capacities. The very coherent genotype ranking obtained with δ(13) C in the different tree compartments has some practical outreach. Because WUE remains largely uncoupled from growth in poplar plantations, there is potential to identify genotypes with satisfactory growth and higher WUE.
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Affiliation(s)
- M S Verlinden
- Department of Biology, Research Group of Plant and Vegetation Ecology, University of Antwerp, Wilrijk, B-2610, Belgium
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Soper FM, Richards AE, Siddique I, Aidar MPM, Cook GD, Hutley LB, Robinson N, Schmidt S. Natural abundance (δ¹⁵N) indicates shifts in nitrogen relations of woody taxa along a savanna-woodland continental rainfall gradient. Oecologia 2014; 178:297-308. [PMID: 25502440 DOI: 10.1007/s00442-014-3176-3] [Citation(s) in RCA: 17] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/19/2014] [Accepted: 11/28/2014] [Indexed: 11/28/2022]
Abstract
Water and nitrogen (N) interact to influence soil N cycling and plant N acquisition. We studied indices of soil N availability and acquisition by woody plant taxa with distinct nutritional specialisations along a north Australian rainfall gradient from monsoonal savanna (1,600-1,300 mm annual rainfall) to semi-arid woodland (600-250 mm). Aridity resulted in increased 'openness' of N cycling, indicated by increasing δ(15)N(soil) and nitrate:ammonium ratios, as plant communities transitioned from N to water limitation. In this context, we tested the hypothesis that δ(15)N(root) xylem sap provides a more direct measure of plant N acquisition than δ(15)N(foliage). We found highly variable offsets between δ(15)N(foliage) and δ(15)N(root) xylem sap, both between taxa at a single site (1.3-3.4 ‰) and within taxa across sites (0.8-3.4 ‰). As a result, δ(15)N(foliage) overlapped between N-fixing Acacia and non-fixing Eucalyptus/Corymbia and could not be used to reliably identify biological N fixation (BNF). However, Acacia δ(15)N(root) xylem sap indicated a decline in BNF with aridity corroborated by absence of root nodules and increasing xylem sap nitrate concentrations and consistent with shifting resource limitation. Acacia dominance at arid sites may be attributed to flexibility in N acquisition rather than BNF capacity. δ(15)N(root) xylem sap showed no evidence of shifting N acquisition in non-mycorrhizal Hakea/Grevillea and indicated only minor shifts in Eucalyptus/Corymbia consistent with enrichment of δ(15)N(soil) and/or decreasing mycorrhizal colonisation with aridity. We propose that δ(15)N(root) xylem sap is a more direct indicator of N source than δ(15)N(foliage), with calibration required before it could be applied to quantify BNF.
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Affiliation(s)
- Fiona M Soper
- Department of Ecology and Evolutionary Biology, Cornell University, Ithaca, NY, 14853, USA,
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Ren H, Xu Z, Zhang W, Jiang L, Huang J, Chen S, Wang L, Han X. Linking ethylene to nitrogen-dependent leaf longevity of grass species in a temperate steppe. ANNALS OF BOTANY 2013; 112:1879-1885. [PMID: 24136876 PMCID: PMC3838550 DOI: 10.1093/aob/mct223] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/20/2013] [Accepted: 08/07/2013] [Indexed: 06/02/2023]
Abstract
BACKGROUND AND AIMS Leaf longevity is an important plant functional trait that often varies with soil nitrogen supply. Ethylene is a classical plant hormone involved in the control of senescence and abscission, but its role in nitrogen-dependent leaf longevity is largely unknown. METHODS Pot and field experiments were performed to examine the effects of nitrogen addition on leaf longevity and ethylene production in two dominant plant species, Agropyron cristatum and Stipa krylovii, in a temperate steppe in northern China. KEY RESULTS Nitrogen addition increased leaf ethylene production and nitrogen concentration but shortened leaf longevity; the addition of cobalt chloride, an ethylene biosynthesis inhibitor, reduced leaf nitrogen concentration and increased leaf longevity. Path analysis indicated that nitrogen addition reduced leaf longevity mainly through altering leaf ethylene production. CONCLUSIONS These findings provide the first experimental evidence in support of the involvement of ethylene in nitrogen-induced decrease in leaf longevity.
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Affiliation(s)
- Haiyan Ren
- State Key Laboratory of Forest and Soil Ecology, Institute of Applied Ecology, The Chinese Academy of Sciences, Shenyang, 110164, China
- State Key Laboratory of Vegetation and Environmental Change, Institute of Botany, The Chinese Academy of Sciences, Beijing, 100093, China
| | - Zhuwen Xu
- State Key Laboratory of Forest and Soil Ecology, Institute of Applied Ecology, The Chinese Academy of Sciences, Shenyang, 110164, China
| | - Wenhao Zhang
- State Key Laboratory of Vegetation and Environmental Change, Institute of Botany, The Chinese Academy of Sciences, Beijing, 100093, China
| | - Lin Jiang
- School of Biology, Georgia Institute of Technology, Atlanta, GA 30332, USA
| | - Jianhui Huang
- State Key Laboratory of Vegetation and Environmental Change, Institute of Botany, The Chinese Academy of Sciences, Beijing, 100093, China
| | - Shiping Chen
- State Key Laboratory of Vegetation and Environmental Change, Institute of Botany, The Chinese Academy of Sciences, Beijing, 100093, China
| | - Lixin Wang
- Department of Earth Sciences, Indiana University-Purdue University, Indianapolis (IUPUI), Indianapolis, IN 46202, USA
| | - Xingguo Han
- State Key Laboratory of Forest and Soil Ecology, Institute of Applied Ecology, The Chinese Academy of Sciences, Shenyang, 110164, China
- State Key Laboratory of Vegetation and Environmental Change, Institute of Botany, The Chinese Academy of Sciences, Beijing, 100093, China
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Liu G, Xie X, Ye D, Ye X, Tuvshintogtokh I, Mandakh B, Huang Z, Dong M. Plant functional diversity and species diversity in the Mongolian steppe. PLoS One 2013; 8:e77565. [PMID: 24116233 PMCID: PMC3792920 DOI: 10.1371/journal.pone.0077565] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/13/2013] [Accepted: 09/03/2013] [Indexed: 11/19/2022] Open
Abstract
BACKGROUND The Mongolian steppe is one of the most important grasslands in the world but suffers from aridization and damage from anthropogenic activities. Understanding structure and function of this community is important for the ecological conservation, but has seldom been investigated. METHODOLOGY/PRINCIPAL FINDINGS In this study, a total of 324 quadrats located on the three main types of Mongolian steppes were surveyed. Early-season perennial forbs (37% of total importance value), late-season annual forbs (33%) and late-season perennial forbs (44%) were dominant in meadow, typical and desert steppes, respectively. Species richness, diversity and plant functional type (PFT) richness decreased from the meadow, via typical to desert steppes, but evenness increased; PFT diversity in the desert and meadow steppes was higher than that in typical steppe. However, above-ground net primary productivity (ANPP) was far lower in desert steppe than in the other two steppes. In addition, the slope of the relationship between species richness and PFT richness increased from the meadow, via typical to desert steppes. Similarly, with an increase in species diversity, PFT diversity increased more quickly in both the desert and typical steppes than that in meadow steppe. Random resampling suggested that this coordination was partly due to a sampling effect of diversity. CONCLUSIONS/SIGNIFICANCE These results indicate that desert steppe should be strictly protected because of its limited functional redundancy, which its ecological functioning is sensitive to species loss. In contrast, despite high potential forage production shared by the meadow and typical steppes, management of these two types of steppes should be different: meadow steppe should be preserved due to its higher conservation value characterized by more species redundancy and higher spatial heterogeneity, while typical steppe could be utilized moderately because its dominant grass genus Stipa is resistant to herbivory and drought.
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Affiliation(s)
- Guofang Liu
- State Key Laboratory of Vegetation and Environmental Change, Institute of Botany, Chinese Academy of Sciences, Beijing, China
| | - Xiufang Xie
- State Key Laboratory of Vegetation and Environmental Change, Institute of Botany, Chinese Academy of Sciences, Beijing, China
- University of Chinese Academy of Sciences, Beijing, China
| | - Duo Ye
- State Key Laboratory of Vegetation and Environmental Change, Institute of Botany, Chinese Academy of Sciences, Beijing, China
- University of Chinese Academy of Sciences, Beijing, China
| | - Xuehua Ye
- State Key Laboratory of Vegetation and Environmental Change, Institute of Botany, Chinese Academy of Sciences, Beijing, China
| | | | - Bayart Mandakh
- Institute of Botany, Mongolian Academy of Sciences, Ulaanbaatar, Mongolia
| | - Zhenying Huang
- State Key Laboratory of Vegetation and Environmental Change, Institute of Botany, Chinese Academy of Sciences, Beijing, China
| | - Ming Dong
- State Key Laboratory of Vegetation and Environmental Change, Institute of Botany, Chinese Academy of Sciences, Beijing, China
- College of Life and Environmental Sciences, Hangzhou Normal University, Hangzhou, China
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Hirose T, Oikawa S. Mean residence time of leaf number, area, mass, and nitrogen in canopy photosynthesis. Oecologia 2012; 169:927-37. [DOI: 10.1007/s00442-012-2266-3] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/02/2011] [Accepted: 01/19/2012] [Indexed: 11/29/2022]
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Zhu Q, Jiang H, Peng C, Liu J, Wei X, Fang X, Liu S, Zhou G, Yu S. Evaluating the effects of future climate change and elevated CO2 on the water use efficiency in terrestrial ecosystems of China. Ecol Modell 2011. [DOI: 10.1016/j.ecolmodel.2010.09.035] [Citation(s) in RCA: 50] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/18/2022]
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Hall SJ, Sponseller RA, Grimm NB, Huber D, Kaye JP, Clark C, Collins SL. Ecosystem response to nutrient enrichment across an urban airshed in the Sonoran Desert. ECOLOGICAL APPLICATIONS : A PUBLICATION OF THE ECOLOGICAL SOCIETY OF AMERICA 2011; 21:640-660. [PMID: 21639034 DOI: 10.1890/10-0758.1] [Citation(s) in RCA: 20] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/30/2023]
Abstract
Rates of nitrogen (N) deposition have increased in arid and semiarid ecosystems, but few studies have examined the impacts of long-term N enrichment on ecological processes in deserts. We conducted a multiyear, nutrient-addition study within 15 Sonoran Desert sites across the rapidly growing metropolitan area of Phoenix, Arizona (USA). We hypothesized that desert plants and soils would be sensitive to N enrichment, but that these effects would vary among functional groups that differ in terms of physiological responsiveness, proximity to surface N sources, and magnitude of carbon (C) or water limitation. Inorganic N additions augmented net potential nitrification in soils, moreso than net potential N mineralization, highlighting the important role of nitrifying microorganisms in the nitrate economy of drylands. Winter annual plants were also responsive to nutrient additions, exhibiting a climate-driven cascade of resource limitation, from little to no production in seasons of low rainfall (winter 2006 and 2007), to moderate N limitation with average precipitation (winter 2009), to limitation by both N and P in a season of above-normal rainfall (winter 2008). Herbaceous production is a potentially important mechanism of N retention in arid ecosystems, capable of immobilizing an amount equal to or greater than that deposited annually to soils in this urban airshed. However, interannual variability in precipitation and abiotic processes that limit the incorporation of detrital organic matter into soil pools may limit this role over the long term. In contrast, despite large experimental additions of N and P over four years, growth of Larrea tridentata, the dominant perennial plant of the Sonoran Desert, was unresponsive to nutrient enrichment, even during wet years. Finally, there did not appear to be strong ecological interactions between nutrient addition and location relative to the city, despite the nearby activity of nearly four million people, perhaps due to loss or transfer pathways that limit long-term N enrichment of ecosystems by the urban atmosphere.
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Affiliation(s)
- Sharon J Hall
- School of Life Sciences, Arizona State University, Tempe, Arizona 85287-4501, USA.
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Ren H, Xu Z, Huang J, Clark C, Chen S, Han X. Nitrogen and water addition reduce leaf longevity of steppe species. ANNALS OF BOTANY 2011; 107:145-55. [PMID: 21084404 PMCID: PMC3002476 DOI: 10.1093/aob/mcq219] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/11/2010] [Revised: 09/30/2010] [Accepted: 10/04/2010] [Indexed: 05/10/2023]
Abstract
BACKGROUND AND AIMS Changes in supplies of resources will modify plant functional traits. However, few experimental studies have addressed the effects of nitrogen and water variations, either singly or in combination, on functional traits. METHODS A 2-year field experiment was conducted to test the effects of nitrogen and water addition on leaf longevity and other functional traits of the two dominant (Agropyron cristatum and Stipa krylovii) and three most common species (Cleistogenes squarrosa, Melilotoides ruthenica and Potentilla tanacetifolia) in a temperate steppe in northern China. KEY RESULTS Additional nitrogen and water increased leaf nitrogen content and net photosynthetic rate, and changed other measured functional traits. Leaf longevity decreased significantly with both nitrogen addition (-6 days in 2007 and -5·4 days in 2008; both P < 0·001) and watering (-13 days in 2007 and -9·9 days in 2008; both P < 0·001), and significant differences in leaf longevity were also found among species. Nitrogen and water interacted to affect leaf longevity and other functional traits. Soil water content explained approx. 70 % of the shifts in leaf longevity. Biomass at both species and community level increased under water and nitrogen addition because of the increase in leaf biomass production per individual plant. CONCLUSIONS The results suggest that additional nitrogen and water supplies reduce plant leaf longevity. Soil water availability might play a fundamental role in determining leaf longevity and other leaf functional traits, and its effects can be modified by soil nitrogen availability in semi-arid areas. The different responses of species to resource alterations may cause different global change ramifications under future climate change scenarios.
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Affiliation(s)
- Haiyan Ren
- State Key Laboratory of Vegetation and Environmental Change, Institute of Botany, Chinese Academy of Sciences, Xiangshan, Beijing 100093, China
- Graduate University of the Chinese Academy of Sciences, Yuquanlu, Beijing 100049, China
| | - Zhuwen Xu
- Institute of Applied Ecology, Chinese Academy of Sciences, Shenyang, 110016, China
| | - Jianhui Huang
- State Key Laboratory of Vegetation and Environmental Change, Institute of Botany, Chinese Academy of Sciences, Xiangshan, Beijing 100093, China
| | - Christopher Clark
- School of Life Sciences and Global Institute of Sustainability, Arizona State University, Tempe, AZ 85287–4501, USA
| | - Shiping Chen
- State Key Laboratory of Vegetation and Environmental Change, Institute of Botany, Chinese Academy of Sciences, Xiangshan, Beijing 100093, China
| | - Xingguo Han
- State Key Laboratory of Vegetation and Environmental Change, Institute of Botany, Chinese Academy of Sciences, Xiangshan, Beijing 100093, China
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Suárez N. Leaf lifetime photosynthetic rate and leaf demography in whole plants of Ipomoea pes-caprae growing with a low supply of calcium, a 'non-mobile' nutrient. JOURNAL OF EXPERIMENTAL BOTANY 2010; 61:843-55. [PMID: 20080828 PMCID: PMC2814114 DOI: 10.1093/jxb/erp351] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/03/2009] [Revised: 11/05/2009] [Accepted: 11/09/2009] [Indexed: 05/12/2023]
Abstract
The adaptive significance of leaf longevity has been established in relation to restrictive nutrients that can be retranslocated within the plant. However, the effect of deficiencies in 'non-mobile' nutrients on leaf lifespan and photosynthetic carbon gain is uncertain. Calcium is frequently given as an example of an essential nutrient with low phloem mobility that may alter the leaf senescence process. This study has been designed to estimate leaf lifespan, leaf production (L(p)) and leaf death (L(d)) rates, the age structure of leaves, and the decline in maximum photosynthetic rate (A(max)) with age in plants of Ipomoea pes-caprae growing with a full supply of nutrients and with a low Ca supply. The Ca deficiency produced reductions in L(p) and leaf lifespan compared with control plants. In spite of the differences in the demographic parameters between treatments in control and low-Ca plants, the percentage of leaves of a given leaf age class is maintained in such a way that the number of leaves per plant continues to increase. No relationship was found between Ca supply and A(max). However, the decline in A(max) with leaf senescence was rather sudden in control plants compared with plants growing with a low Ca supply. The importance of simultaneously using the total leaf demographic census and the assimilation rate along with leaf lifespan data in order to understand the performance of whole plants under constrained conditions is discussed.
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Affiliation(s)
- N Suárez
- Departamento de Biología de Organismos, Universidad Simón Bolívar, Apartado 89.000, Caracas 1080-A, Venezuela.
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Ventura J, Gutiérrez-Sanchez G, Rodríguez-Herrera R, Aguilar CN. Fungal cultures of tar bush and creosote bush for production of two phenolic antioxidants (Pyrocatechol and Gallic acid). Folia Microbiol (Praha) 2009; 54:199-203. [DOI: 10.1007/s12223-009-0031-8] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/19/2008] [Revised: 03/02/2009] [Indexed: 10/20/2022]
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Jones JB, Diane W. MICROHABITAT-SPECIFIC CONTROLS ON SOIL RESPIRATION AND DENITRIFICATION IN THE MOJAVE DESERT: THE ROLE OF HARVESTER ANT NESTS AND VEGETATION. WEST N AM NATURALIST 2006. [DOI: 10.3398/1527-0904(2006)66[426:mcosra]2.0.co;2] [Citation(s) in RCA: 14] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022]
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19
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Plasticity in Resource Allocation and Nitrogen-use Efficiency in Riparian Vegetation: Implications for Nitrogen Retention. Ecosystems 2006. [DOI: 10.1007/s10021-006-0159-1] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/26/2022]
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Increases in Desert Shrub Productivity under Elevated Carbon Dioxide Vary with Water Availability. Ecosystems 2006. [DOI: 10.1007/s10021-005-0124-4] [Citation(s) in RCA: 46] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/24/2022]
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21
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Barker DH, Vanier C, Naumburg E, Charlet TN, Nielsen KM, Newingham BA, Smith SD. Enhanced monsoon precipitation and nitrogen deposition affect leaf traits and photosynthesis differently in spring and summer in the desert shrub Larrea tridentata. THE NEW PHYTOLOGIST 2006; 169:799-808. [PMID: 16441760 DOI: 10.1111/j.1469-8137.2006.01628.x] [Citation(s) in RCA: 25] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/06/2023]
Abstract
Leaf-level CO2 assimilation (A(area)) can largely be predicted from stomatal conductance (g(s)), leaf morphology (SLA) and nitrogen (N) content (N(area)) in species across biomes and functional groups. The effects of simulated global change scenarios, increased summer monsoon rain (+H2O), N deposition (+N) and the combination (+H2O +N), were hypothesized to affect leaf trait-photosynthesis relationships differently in the short- and long-term for the desert shrub Larrea tridentata. During the spring, +H2O and +H2O +N plants had lower A(area) and g(s), but similar shoot water potential (Psi(shoot)) compared with control and +N plants; differences in A(area) were attributed to lower leaf N(area) and g(s). During the summer, +H2O and +H2O +N plants displayed higher A(area) than control and +N plants, which was attributed to higher Psi(shoot), g(s) and SLA. Throughout the year, A(area) was strongly correlated with g(s) but weakly correlated with leaf N(area) and SLA. We concluded that increased summer monsoon had a stronger effect on the performance of Larrea than increased N deposition. In the short term, the +H2O and +H2O +N treatments were associated with increasing A(area) in summer, but also with low leaf N(area) and lower A(area) in the long term the following spring.
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Affiliation(s)
- D H Barker
- Department of Biological Sciences, University of Nevada Las Vegas, Las Vegas, NV 89154-4004, USA.
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22
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Shen W, Wu J, Kemp PR, Reynolds JF, Grimm NB. Simulating the dynamics of primary productivity of a Sonoran ecosystem: Model parameterization and validation. Ecol Modell 2005. [DOI: 10.1016/j.ecolmodel.2005.04.010] [Citation(s) in RCA: 26] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/25/2022]
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23
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Lovelock CE, Feller IC, Mckee KL, Engelbrecht BMJ, Ball MC. The effect of nutrient enrichment on growth, photosynthesis and hydraulic conductance of dwarf mangroves in Panama. Funct Ecol 2004. [DOI: 10.1046/j.0269-8463.2004.00805.x] [Citation(s) in RCA: 148] [Impact Index Per Article: 7.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022]
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Hamerlynck EP, Huxman TE, McAuliffe JR, Smith SD. Carbon isotope discrimination and foliar nutrient status of Larrea tridentata (creosote bush) in contrasting Mojave Desert soils. Oecologia 2003; 138:210-5. [PMID: 14625769 DOI: 10.1007/s00442-003-1437-7] [Citation(s) in RCA: 39] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/26/2003] [Accepted: 10/21/2003] [Indexed: 10/26/2022]
Abstract
We investigated the relationships between foliar stable carbon isotope discrimination (Delta), % foliar N, and predawn water potentials (psi(pd)) and midday stomatal conductance ( g(s)) of Larrea tridentata across five Mojave Desert soils with different age-specific surface and sub-surface horizon development and soil hydrologies. We wished to elucidate how this long-lived evergreen shrub optimizes leaf-level physiological performance across soils with physicochemical characteristics that affect the distribution of limiting water and nitrogen resources. We found that in young, coarse alluvial soils that permit water infiltration to deeper soil horizons, % foliar N was highest and Delta, g(s) and psi(pd) were lowest, while %N was lowest and Delta, g(s) and psi(pd) were highest in fine sandy soils; Larrea growing in older soils with well-developed surface and sub-surface horizons exhibited intermediate values for these parameters. Delta showed negative linear relationships with % N (R(2)=0.54) and a positive relationship with psi(pd) (R(2)=0.14). Multiple regression analyses showed a strong degree of multicolinearity of g(s) and Delta with psi(pd) and N, suggesting that soil-mediated distribution of co-limiting water and nitrogen resources was the primary determinant of stomatal behavior, which is the primary limitation to productivity in this shrub. These findings show that subtle changes in the soil medium plays a strong role in the spatial and temporal distribution and utilization of limiting water and nitrogen resources by this long-lived desert evergreen, and that this role can be detected through carbon isotope ratios.
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Affiliation(s)
- Erik P Hamerlynck
- Department of Biological Sciences, Rutgers University, 101 Warren St., Newark, NJ 07102-1811, USA.
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25
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Lovelock CE, Feller IC. Photosynthetic performance and resource utilization of two mangrove species coexisting in a hypersaline scrub forest. Oecologia 2003; 134:455-62. [PMID: 12647116 DOI: 10.1007/s00442-002-1118-y] [Citation(s) in RCA: 83] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/27/2002] [Accepted: 10/14/2002] [Indexed: 11/28/2022]
Abstract
In a hypersaline mangrove scrub forest in northern Florida, coexisting trees of Laguncularia racemosa and Avicennia germinans were either fertilized with nitrogen or phosphorus, or not fertilized (controls). We aimed to test whether nutrient additions differentially altered photosynthetic performance and resource utilization in these two species. In control trees, photosynthetic rates were higher in L. racemosa than A. germinans. However, leaf nitrogen concentrations were higher in A. germinans than L. racemosa. Avicennia germinans responded to fertilization with nitrogen by increasing leaf nitrogen concentrations and rates of photosynthesis such that they were equivalent to photosynthesis in L. racemosa. Laguncularia racemosa did not show a response to nitrogen additions. Neither species showed strong responses to phosphorus fertilization. Avicennia germinans had high photosynthetic water-use efficiency (photosynthesis/transpiration), but low photosynthetic nitrogen-use efficiency (photosynthesis/leaf nitrogen). In contrast, L. racemosa had comparatively low photosynthetic water use efficiency and high photosynthetic nitrogen use efficiency. Leaf level characteristics lead us to hypothesize that coexistence of A. germinans and L. racemosa should occur where nitrogen levels are low and salinity is moderate, or at least moderate for some period of the year.
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Affiliation(s)
- Catherine E Lovelock
- Smithsonian Environmental Research Center, P.O. Box 28, Edgewater, MD 21037, USA.
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Reynolds JF, Virginia RA, Kemp PR, de Soyza AG, Tremmel DC. IMPACT OF DROUGHT ON DESERT SHRUBS: EFFECTS OF SEASONALITY AND DEGREE OF RESOURCE ISLAND DEVELOPMENT. ECOL MONOGR 1999. [DOI: 10.1890/0012-9615(1999)069[0069:iodods]2.0.co;2] [Citation(s) in RCA: 348] [Impact Index Per Article: 13.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/18/2022]
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Abstract
Since leaves are essentially energy-gaining organs, the arrangement of leaves in time (leaf phenology) and in space (canopy architecture) in both seasonal and nonseasonal environments can be viewed as a central element in plant strategies for carbon gain. Interrelationships among leaf longevity, leaf habit, and leaf-emergence pattern together with shoot architecture affect plant productivity. Leaf longevity is shown to maximize carbon gain through three parameters: leaf photosynthetic rate, the decrease in photosynthetic rate with leaf age, and the initial construction costs of the leaf. This theoretical approach has been extended to seasonal environments and effectively simulated the geographical pattern of leaf habits. To avoid self-shading, plants adopt two alternative modes of leaf emergence. One is successive leaf emergence, in which plants expand one leaf at a time on a shoot; this unshaded leaf utilizes full sunlight and is only replaced by a second leaf when its photosynthetic ability declines. Plants with successive leaf emergence attain high production and have straight shoots with multilayered canopy architecture. The alternative is simultaneous leaf emergence on shoots inclined to minimize self-shading through a monolayered canopy architecture. By the inclination of the shoot, each leaf on the shoot can receive sufficient light. Plants with simultaneous leaf emergence utilize the entire growing period effectively. Taken together and in the context of shoot and canopy architecture these interrelationships among leaf longevity, habit, and emergence pattern provide the basis for a synthetic theory of leaf phenology. Key words: leaf phenology, leaf longevity, leaf emergence, evergreen, deciduous habit.
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31
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Bowman WD, Theodose TA, Fisk MC. Physiological and production responses of plant growth forms to increases in limiting resources in alpine tundra: implications for differential community response to environmental change. Oecologia 1995; 101:217-227. [DOI: 10.1007/bf00317287] [Citation(s) in RCA: 87] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/06/1994] [Accepted: 09/13/1994] [Indexed: 11/28/2022]
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Forest growth along a rainfall gradient in Hawaii: Acacia koa stand structure, productivity, foliar nutrients, and water- and nutrient-use efficiencies. Oecologia 1995; 102:277-284. [PMID: 28306838 DOI: 10.1007/bf00329794] [Citation(s) in RCA: 32] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/15/1994] [Accepted: 01/05/1995] [Indexed: 10/26/2022]
Abstract
We tested whether variation in growth of native koa (Acacia koa) forest along a rainfall gradient was attributable to differences in leaf area index (LAI) or to differences in physiological performance per unit of leaf area. Koa stands were studied on western Kauai prior to Hurricane Iniki, and ranged from 500 to 1130 m elevation and from 850 to 1800 mm annual precipitation. Koa stands along the gradient had basal area ranging from 8 to 42 m2/ha, LAI ranging from 1.4 to 5.4, and wood increment ranging from 0.7 to 7.1 tonnes/ha/year. N, P, and K contents by weight of sun leaves (phyllodes) were negatively correlated with specific leaf mass (SLM, g m-2) across sites; on a leaf area basis, N increased whereas P and K decreased with SLM. LAI, aboveground woody biomass increment, and production per unit leaf area (E) increased as phyllode δ13C became more negative. The δ13C data suggested that intrinsic water-use efficiency (ratio of assimilation to conductance) increased as water availability decreased. In five of the six sites, phyllode P contents increased as LAI increased, but biomass increment and E were not correlated with phyllode nutrient contents, suggesting that productivity was limited more by water than by nutrient availability. Because vapor pressure deficits increased with decreasing elevation, actual water-use efficiency (ratio of assimilation to transpiration) was lower at drier, low-elevation sites. There was a trade-off between intrinsic water-use efficiency and production per unit of canopy N or P across the gradient. In summary, koa responds to water limitation both by reducing stand LAI and by adjusting gas exchange, which results in increased intrinsic water-use efficiency but decreased E.
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Whitford WG, Martinez-Turanzas G, Martinez-Meza E. Persistence of desertified ecosystems: Explanations and implications. ENVIRONMENTAL MONITORING AND ASSESSMENT 1995; 37:319-332. [PMID: 24197858 DOI: 10.1007/bf00546898] [Citation(s) in RCA: 16] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/02/2023]
Abstract
Studies of rainfall partitioning by shrubs, responses of shrub-dominated ecosystems to herbicide treatment, and experiments using drought and supplemental rainfall were conducted to test the hypothesis that the shrub-dominated ecosystems that have replaced desert grasslands are resistant and resilient to disturbance. Between 16 and 25% of the intercepted rainfall is channelized to deep soil storage by stemflow and root channelization. Stemflow water is nutrient enriched and contributes to the "islands of fertility" that develop under desert shrubs. Drought and rainfall augmentation experiments during the growing season after 5 consecutive years of summer drought found that (1) growth of creosotebushes, Larrea tridentata, was not significantly affected, (2) perennial grasses and forbs disappeared on droughted plots, (3) nitrogen mineralization increased in the short term, and (4) densities and biomass of spring annual plants increased on the droughted plots. Doubling summer rainfall for 5 consecutive years had less-significant effects. Coppice dunes treated with herbicide in 1979 to kill mesquite (Prosopis glandulosa) had the same frequency of occurrence of the shrub as the untreated dunes when remeasured in 1993. These data indicate that the shrub-dominated ecosystems persist because they are resistant and resilient to climatic and anthropogenic stresses.
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Affiliation(s)
- W G Whitford
- US-EPA, Environmental Monitoring Research Laboratory, PO Box 93478, 89193, Las Vegas, NV, USA
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Marshall JD, Dawson TE, Ehleringer JR. Integrated nitrogen, carbon, and water relations of a xylem-tapping mistletoe following nitrogen fertilization of the host. Oecologia 1994; 100:430-438. [PMID: 28306932 DOI: 10.1007/bf00317865] [Citation(s) in RCA: 37] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/18/1994] [Accepted: 07/30/1994] [Indexed: 10/26/2022]
Abstract
Xylem-tapping mistletoes transpire large volumes of water (E) while conducting photosynthesis (A) at low rates, thus maintaining low instantaneous wateruse efficiency (A/E). These gas-exchange characteristics have been interpreted as a means of facilitating assimilation of nitrogen dissolved at low concentration in host xylem water; however, low A/E also results in substantial heterotrophic carbon gain. In this study, host trees (Juniperus osteosperma) were fertilized and gas exchange of mistletoe (Phoradendron juniperinum) and host were monitored to determine whether mistletoe A/E would approach that of the host if mistletoes were supplied with abundant nitrogen. Fertilization significantly increased foliar N concentrations (N), net assimilation rates, and A/E in both mistletoe and host. However, at any given N concentration, mistletoes maintained lower A and lower A/E than their hosts. On the other hand, when instantaneous water-use efficiency and A/N were calculated to include heterotrophic assimilation of carbon dissolved in the xylem sap of the host, both water-use efficiency and A/N converged on host values. A simple model of Phoradendron carbon and nitrogen budgets was constructed to analyze the relative benefits of nitrogen- and carbonparasitism. The model assumes constant E and includes feedbacks of tissue nitrogen concentration on photosyn-thesis. These results, combined with our earlier observation that net assimilation rates of mistletoes and their hosts are approximately matched (Marshall et al. 1994), support part of the nitrogen-parasitism hypothesis: that high rates of transpiration benefit the mistletoe primarily through nitrogen gain. However, the low ratio of A/E is interpreted not as a means of acquiring nitrogen, but as an inevitable consequence of an imbalance in C and N assimilation.
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Affiliation(s)
- John D Marshall
- Department of Forest Resources, University of Idaho, 83843, Moscow, ID, USA
| | - Todd E Dawson
- Section of Ecology and Systematics, Cornell University, 14853-2701, Ithaca, NY, USA
| | - James R Ehleringer
- Department of Biology, University of Utah, 84112, Salt Lake City, UT, USA
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Effects of plant size and water relations on gas exchange and growth of the desert shrub Larrea tridentata. Oecologia 1994; 97:171-178. [DOI: 10.1007/bf00323146] [Citation(s) in RCA: 46] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/12/1993] [Accepted: 11/15/1993] [Indexed: 10/26/2022]
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36
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Shoot growth dynamics and photosynthetic response to increased nitrogen availability in the alpine willow Salix glauca. Oecologia 1994; 97:93-99. [DOI: 10.1007/bf00317912] [Citation(s) in RCA: 26] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/22/1993] [Accepted: 11/08/1993] [Indexed: 10/26/2022]
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Lajtha K, Getz J. Photosynthesis and water-use efficiency in pinyon-juniper communities along an elevation gradient in northern New Mexico. Oecologia 1993; 94:95-101. [PMID: 28313865 DOI: 10.1007/bf00317308] [Citation(s) in RCA: 61] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/28/1992] [Accepted: 11/02/1992] [Indexed: 11/27/2022]
Abstract
We investigated plant ecophysiological response to fertilization of selected sites along an elevation gradient in a pinyon-juniper woodland. Plant density and species composition followed typical patterns for pinyon-juniper woodlands over this gradient, with a sparse juniper (Juniperus monosperma (Engelm.) Sarg.)-grassland community at the lowest elevation and gradually increasing total canopy cover and pinyon (Pinus edulis Engelm.) cover with elevation. Carbon isotope analysis showed that both tree species had higher water-use efficiency (WUE) at the lowest, and presumably driest, sites. Over most of the gradient, however, it appeared that changes in stand density compensated for changes in water availability. Contrary to initial hypotheses, the more drought-tolerant juniper did not demonstrate significantly greater WUE than pinyon, although it maintained positive carbon gain at lower predawn xylem pressure potentials than pinyon. In pinyon, both A max and WUE increased with increasing N concentration in tissues. Pinyon needles also demonstrated declining nitrogen-use efficiency with age. There was no relationship between tissue N and either A max or WUE measured at A max in juniper, although δ13C analysis indicated that WUE increased in juniper with increased N availability. Results from this study suggest that plasticity in plant physiological processes could result in nonlinear responses of organic matter production to climate change, and therefore must be accounted for in ecosystem models.
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Affiliation(s)
- K Lajtha
- Department of Biology, Boston University, 5 Cummington Street, 02215, Boston, MA, USA
| | - J Getz
- Department of Biology, Boston University, 5 Cummington Street, 02215, Boston, MA, USA
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The efficiency of nitrogen retranslocation from leaf biomass in Quercus ilex ecosystems. ACTA ACUST UNITED AC 1992. [DOI: 10.1007/bf00118229] [Citation(s) in RCA: 28] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/26/2022]
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Escudero A, del Arco JM, Sanz IC, Ayala J. Effects of leaf longevity and retranslocation efficiency on the retention time of nutrients in the leaf biomass of different woody species. Oecologia 1992; 90:80-87. [DOI: 10.1007/bf00317812] [Citation(s) in RCA: 196] [Impact Index Per Article: 6.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/28/1991] [Accepted: 10/12/1991] [Indexed: 11/29/2022]
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