1
|
Rinehart S, Dybiec JM, Mortazavi B, Cherry JA. Stratified vertical sediment profiles increase burrowing crab effects on salt marsh edaphic conditions. Ecosphere 2023. [DOI: 10.1002/ecs2.4431] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 03/16/2023] Open
Affiliation(s)
- S. Rinehart
- Department of Biological Sciences University of Alabama Tuscaloosa Alabama USA
| | - J. M. Dybiec
- Department of Biological Sciences University of Alabama Tuscaloosa Alabama USA
| | - B. Mortazavi
- Department of Biological Sciences University of Alabama Tuscaloosa Alabama USA
| | - J. A. Cherry
- Department of Biological Sciences University of Alabama Tuscaloosa Alabama USA
- New College University of Alabama Tuscaloosa Alabama USA
| |
Collapse
|
2
|
Pellegrini E, Incerti G, Pedersen O, Moro N, Foscari A, Casolo V, Contin M, Boscutti F. Flooding and Soil Properties Control Plant Intra- and Interspecific Interactions in Salt Marshes. PLANTS 2022; 11:plants11151940. [PMID: 35893643 PMCID: PMC9331060 DOI: 10.3390/plants11151940] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 06/23/2022] [Revised: 07/15/2022] [Accepted: 07/22/2022] [Indexed: 11/16/2022]
Abstract
The stress gradient hypothesis (SGH) states that plant-plant interactions shift from competition to facilitation in increasing stress conditions. In salt marshes, edaphic properties can weaken the application of the SGH by amplifying the intensity of flooding and controlling plant zonation. We identified facilitative and competitive interactions along flooding gradients and tested the role of edaphic properties in exacerbating stress and shaping plant-plant interactions. Morphological traits of two target halophytes (Limonium narbonense and Sarcocornia fruticosa), flooding intensity, soil texture and soil organic C were recorded. The relative plant fitness index was assessed for the two species based on the relative growth in plurispecific rather than monospecific plant communities. Plant fitness increased with increasing stress supporting the SGH. L. narbonense showed larger fitness in plurispecific stands whereas S. fruticosa performed better in conspecific stands. Significant intra- or interspecific interactions were observed along the stress gradient defined by the combination of flooding and clay content in soil. When considering the limited soil organic C as stressor, soil properties were more important than flooding in defining plant-plant interactions. We highlight the need for future improvements of the SGH approach by including edaphic stressors in the model and their possible interactions with the main abiotic drivers of zonation.
Collapse
Affiliation(s)
- Elisa Pellegrini
- Department of Agricultural, Food, Environmental and Animal Sciences, University of Udine, Via delle Scienze 206, 33100 Udine, Italy; (G.I.); (N.M.); (A.F.); (V.C.); (M.C.); (F.B.)
- Department of Biology, University of Copenhagen, Universitetsparken 4, 2100 Copenhagen, Denmark;
- Correspondence:
| | - Guido Incerti
- Department of Agricultural, Food, Environmental and Animal Sciences, University of Udine, Via delle Scienze 206, 33100 Udine, Italy; (G.I.); (N.M.); (A.F.); (V.C.); (M.C.); (F.B.)
| | - Ole Pedersen
- Department of Biology, University of Copenhagen, Universitetsparken 4, 2100 Copenhagen, Denmark;
| | - Natasha Moro
- Department of Agricultural, Food, Environmental and Animal Sciences, University of Udine, Via delle Scienze 206, 33100 Udine, Italy; (G.I.); (N.M.); (A.F.); (V.C.); (M.C.); (F.B.)
| | - Alessandro Foscari
- Department of Agricultural, Food, Environmental and Animal Sciences, University of Udine, Via delle Scienze 206, 33100 Udine, Italy; (G.I.); (N.M.); (A.F.); (V.C.); (M.C.); (F.B.)
| | - Valentino Casolo
- Department of Agricultural, Food, Environmental and Animal Sciences, University of Udine, Via delle Scienze 206, 33100 Udine, Italy; (G.I.); (N.M.); (A.F.); (V.C.); (M.C.); (F.B.)
| | - Marco Contin
- Department of Agricultural, Food, Environmental and Animal Sciences, University of Udine, Via delle Scienze 206, 33100 Udine, Italy; (G.I.); (N.M.); (A.F.); (V.C.); (M.C.); (F.B.)
| | - Francesco Boscutti
- Department of Agricultural, Food, Environmental and Animal Sciences, University of Udine, Via delle Scienze 206, 33100 Udine, Italy; (G.I.); (N.M.); (A.F.); (V.C.); (M.C.); (F.B.)
| |
Collapse
|
3
|
Tanner KE, Wasson K, Parker IM. Competition rather than facilitation affects plant performance across an abiotic stress gradient in a restored California salt marsh. Restor Ecol 2022. [DOI: 10.1111/rec.13746] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Affiliation(s)
- Karen E. Tanner
- Ecology and Evolutionary Biology Department University of California, Santa Cruz, 1156 High Street Santa Cruz CA USA 95064
| | - Kerstin Wasson
- Ecology and Evolutionary Biology Department University of California, Santa Cruz, 1156 High Street Santa Cruz CA USA 95064
- Elkhorn Slough National Estuarine Research Reserve, 1700 Elkhorn Road Watsonville CA USA 95076
| | - Ingrid M. Parker
- Ecology and Evolutionary Biology Department University of California, Santa Cruz, 1156 High Street Santa Cruz CA USA 95064
| |
Collapse
|
4
|
Ren L, Jensen K, Porada P, Mueller P. Biota-mediated carbon cycling-A synthesis of biotic-interaction controls on blue carbon. Ecol Lett 2022; 25:521-540. [PMID: 35006633 DOI: 10.1111/ele.13940] [Citation(s) in RCA: 11] [Impact Index Per Article: 5.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/14/2021] [Revised: 08/03/2021] [Accepted: 11/02/2021] [Indexed: 01/22/2023]
Abstract
Research into biotic interactions has been a core theme of ecology for over a century. However, despite the obvious role that biota play in the global carbon cycle, the effects of biotic interactions on carbon pools and fluxes are poorly understood. Here we develop a conceptual framework that illustrates the importance of biotic interactions in regulating carbon cycling based on a literature review and a quantitative synthesis by means of meta-analysis. Our study focuses on blue carbon ecosystems-vegetated coastal ecosystems that function as the most effective long-term CO2 sinks of the biosphere. We demonstrate that a multitude of mutualistic, competitive and consumer-resource interactions between plants, animals and microbiota exert strong effects on carbon cycling across various spatial scales ranging from the rhizosphere to the landscape scale. Climate change-sensitive abiotic factors modulate the strength of biotic-interaction effects on carbon fluxes, suggesting that the importance of biota-mediated carbon cycling will change under future climatic conditions. Strong effects of biotic interactions on carbon cycling imply that biosphere-climate feedbacks may not be sufficiently represented in current Earth system models. Inclusion of new functional groups in these models, and new approaches to simplify species interactions, may thus improve the predictions of biotic effects on the global climate.
Collapse
Affiliation(s)
- Linjing Ren
- Institute of Plant Science and Microbiology, Universität Hamburg, Hamburg, Germany.,State Key Laboratory of Estuarine and Coastal Research, East China Normal University, Shanghai, P. R. China
| | - Kai Jensen
- Institute of Plant Science and Microbiology, Universität Hamburg, Hamburg, Germany
| | - Philipp Porada
- Institute of Plant Science and Microbiology, Universität Hamburg, Hamburg, Germany
| | - Peter Mueller
- Institute of Plant Science and Microbiology, Universität Hamburg, Hamburg, Germany.,Smithsonian Environmental Research Center, Edgewater, Maryland, USA
| |
Collapse
|
5
|
Namba M, Nakaoka M. Increased salinity stress changes plant productivity and biomass by altering the top‐down controls in eelgrass beds. Ecosphere 2021. [DOI: 10.1002/ecs2.3852] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/11/2022] Open
Affiliation(s)
- Mizuho Namba
- Graduate School of Environmental Science Hokkaido University Sapporo Japan
- Muroran Marine Station Field Science Center for Northern Biosphere Hokkaido University Muroran Japan
| | - Masahiro Nakaoka
- Akkeshi Marine Station Field Science Center for Northern Biosphere Hokkaido University Akkeshi Japan
| |
Collapse
|
6
|
Adams AE, Besozzi EM, Shahrokhi G, Patten MA. A case for associational resistance: Apparent support for the stress gradient hypothesis varies with study system. Ecol Lett 2021; 25:202-217. [PMID: 34775662 DOI: 10.1111/ele.13917] [Citation(s) in RCA: 11] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/02/2021] [Revised: 09/07/2021] [Accepted: 10/18/2021] [Indexed: 11/30/2022]
Abstract
According to the stress gradient hypothesis (SGH), ecological interactions between organisms shift positively as environmental stress increases. In the case of associational resistance, habitat is modified to ameliorate stress, benefitting other organisms. The SGH is contentious due to conflicting evidence and theoretical perspectives, so we adopted a meta-analytic approach to determine if it is widely supported across a variety of contexts, including different kingdoms, ecosystems, habitats, interactions, stressors, and life history stages. We developed an extensive list of Boolean search criteria to search the published ecological literature and successfully detect studies that both directly tested the hypothesis, and those that were relevant but never mentioned it. We found that the SGH is well supported by studies that feature bacteria, plants, terrestrial ecosystems, interspecific negative interactions, adults, survival instead of growth or reproduction, and drought, fire, and nutrient stress. We conclude that the SGH is indeed a broadly relevant ecological hypothesis that is currently held back by cross-disciplinary communication barriers. More SGH research is needed beyond the scope of interspecific plant competition, and more SGH research should feature multifactor stress. There remains a need to account for positive interactions in scientific pursuits, such as associational resistance in tests of the SGH.
Collapse
Affiliation(s)
- Amy E Adams
- Department of Biology, University of Oklahoma, Norman, Oklahoma, USA
| | | | - Golya Shahrokhi
- Oklahoma Biological Survey, University of Oklahoma, Norman, Oklahoma, USA
| | - Michael A Patten
- Ecology Research Group, Faculty of Biosciences and Aquaculture, Nord University, Steinkjer, Norway
| |
Collapse
|
7
|
Walker JB, Grosholz ED, Long JD. Predicting burrowing crab impacts on salt marsh plants. Ecosphere 2021. [DOI: 10.1002/ecs2.3803] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022] Open
Affiliation(s)
- Janet B. Walker
- Biology Department San Diego State University 5500 Campanile Drive San Diego California 92182 USA
- Department of Environmental Science and Policy University of California, Davis One Shields Avenue Davis California 95616 USA
- Southern California Coastal Water Research Project 3535 Harbor Blvd, Suite 110 Costa Mesa California 92626 USA
| | - Edwin D. Grosholz
- Department of Environmental Science and Policy University of California, Davis One Shields Avenue Davis California 95616 USA
| | - Jeremy D. Long
- Biology Department San Diego State University 5500 Campanile Drive San Diego California 92182 USA
| |
Collapse
|
8
|
Lowney AM, Thomson RL. Ecological engineering across a temporal gradient: Sociable weaver colonies create year-round animal biodiversity hotspots. J Anim Ecol 2021; 90:2362-2376. [PMID: 34036578 DOI: 10.1111/1365-2656.13544] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/06/2020] [Accepted: 05/13/2021] [Indexed: 12/01/2022]
Abstract
Animal distribution in a landscape depends mostly on the availability of resources. This can be facilitated by other species that have positive effects on local species diversity and impact community structure. Species that significantly change resource availability are often termed ecosystem engineers. Identifying these species is key but predicting where they have large or small impacts is an even greater challenge. The stress-gradient hypothesis predicts that the importance of facilitative interactions that shape community structure and function will increase in stressful and harsh environments. In most environments, conditions will fluctuate between harsh and benign periods, yet how the impacts of ecosystem engineers will change in different conditions has received little attention. Monitoring for extended periods will increase the understanding of how engineers may mitigate the extreme differences between changing seasons. We investigated the role of sociable weavers Philetairus socius as ecosystem engineers and examined how the association of species to weaver colonies may vary across a seasonal (temporal) gradient. Sociable weavers build large colonies that are home to hundreds of weaver individuals but also host a wide range of other animal species. We investigated the use of weaver colonies by terrestrial and arboreal vertebrates and birds throughout a calendar year, encompassing harsh and benign periods. We demonstrate that the presence of sociable weaver colonies creates centres of animal activity. Colonies were used by the local Kalahari animal community for foraging, shade, territorial behaviours and roosting sites. Furthermore, animal activity increased with increased primary productivity, but this was not restricted to weaver colonies, suggesting that the importance of colonies does not directionally change across environmental conditions. Our results were not consistent with predictions of the stress-gradient hypothesis across a temporal gradient. We demonstrate the importance of sociable weavers as ecological engineers and the significance of their colonies in structuring the surrounding animal community. Colonies appear to provide a range of different resources for different species. Sociable weaver colonies have large ecological importance to local animal communities and, by mitigating environmental stress, may be increasingly important as human-driven climate change advances.
Collapse
Affiliation(s)
- Anthony M Lowney
- FitzPatrick Institute of African Ornithology, DST-NRF Centre of Excellence, University of Cape Town, Rondebosch, South Africa
| | - Robert L Thomson
- FitzPatrick Institute of African Ornithology, DST-NRF Centre of Excellence, University of Cape Town, Rondebosch, South Africa
| |
Collapse
|
9
|
Nuñez JD, Bas CC, Pérez García M, Ocampo EH, Ribeiro PD, Luppi TA. Artificial light at night may increase the predation pressure in a salt marsh keystone species. MARINE ENVIRONMENTAL RESEARCH 2021; 167:105285. [PMID: 33640601 DOI: 10.1016/j.marenvres.2021.105285] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/22/2020] [Revised: 02/15/2021] [Accepted: 02/17/2021] [Indexed: 06/12/2023]
Abstract
Artificial light at night (ALAN) has the potential to alter ecological processes such as the natural dynamics of predator-prey interactions. Although understanding of ALAN effect on faunal groups has increased in recent years, few studies have explicitly tested for direct consequences of ALAN on predator-prey systems. Here, we evaluated the effect of ALAN on juvenile mortality due to cannibalism and general predation of the South American intertidal burrowing crab Neohelice granulata, a key ecosystem engineer of salt marshes. For this, we conducted tethering and crab enclosure experiments for both night and day periods during successive tidal floods in a semidiurnal tidal regime. Both experimental approaches were deployed simultaneously in the field and they lasted four consecutive days during new moon nights. ALAN was simulated by a white LED lamp (30W) with a solar panel as a source of power in five separated areas selected as replicates. For general predation, juvenile survival under ALAN was 44% lower than during the daytime and 61% lower than under natural dark conditions. For cannibalism, juvenile survival under ALAN and during the daytime was similar and about 30% lower than under natural dark conditions. We also found that the abundance of adult male crabs (cannibals) under ALAN was nearly five times higher than at natural dark conditions. Our field experiments provide evidence that ALAN can increase the mortality of juvenile crabs and is at least partially driven by cannibalistic interactions.
Collapse
Affiliation(s)
- J D Nuñez
- Instituto de Investigaciones Marinas y Costeras (IIMyC), FCEyN, Universidad Nacional de Mar del Plata-CONICET, CC1260, (7600), Mar del Plata, Provincia de Buenos Aires, Argentina.
| | - C C Bas
- Instituto de Investigaciones Marinas y Costeras (IIMyC), FCEyN, Universidad Nacional de Mar del Plata-CONICET, CC1260, (7600), Mar del Plata, Provincia de Buenos Aires, Argentina
| | - M Pérez García
- Instituto de Investigaciones Marinas y Costeras (IIMyC), FCEyN, Universidad Nacional de Mar del Plata-CONICET, CC1260, (7600), Mar del Plata, Provincia de Buenos Aires, Argentina
| | - E H Ocampo
- Instituto de Investigaciones Marinas y Costeras (IIMyC), FCEyN, Universidad Nacional de Mar del Plata-CONICET, CC1260, (7600), Mar del Plata, Provincia de Buenos Aires, Argentina
| | - P D Ribeiro
- Instituto de Investigaciones Marinas y Costeras (IIMyC), FCEyN, Universidad Nacional de Mar del Plata-CONICET, CC1260, (7600), Mar del Plata, Provincia de Buenos Aires, Argentina
| | - T A Luppi
- Instituto de Investigaciones Marinas y Costeras (IIMyC), FCEyN, Universidad Nacional de Mar del Plata-CONICET, CC1260, (7600), Mar del Plata, Provincia de Buenos Aires, Argentina
| |
Collapse
|
10
|
Nuñez JD, Sbragaglia V, Spivak ED, Chiaradia NM, Luppi TA. The magnitude of behavioural responses to artificial light at night depends on the ecological context in a coastal marine ecosystem engineer. MARINE ENVIRONMENTAL RESEARCH 2021; 165:105238. [PMID: 33486259 DOI: 10.1016/j.marenvres.2020.105238] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/03/2020] [Revised: 12/10/2020] [Accepted: 12/11/2020] [Indexed: 06/12/2023]
Abstract
Artificial light at night (ALAN) is one of the most extensive human geographic disturbances to wildlife. ALAN can have ecological and evolutionary effects on individual organisms, which in turn can affect populations, communities and ecosystems. Although understanding of the effects of ALAN on the ecology and biology of organisms has increased in recent years, most of these advances are in terrestrial environments, but scarce in marine habitats, especially in ecologically important transition areas such as saltmarshes. Here, we study the effects of ALAN on the behavioural budget (i.e. the proportion of time spent performing feeding, burrow maintenance and concealment) of the South American intertidal crab Neohelice granulata, which is an ecosystem engineer of coastal salt marshes. Moreover, we compared the impact of a gradient of ALAN between two different saltmarshes with contrasting environmental characteristics. Our results showed a relationship between ALAN and the behavioural budget. In particular, we showed that an increase in ALAN drove an increase in time spent maintaining burrows at the expense of time spent concealed in the burrow or feeding outside it. Such effects showed slightly different patterns in the two saltmarshes, possibly related to the reproductive value of burrows for mating and to predation risk. Considering the ecosystem role of N. granulata, we argue that the different effect of ALAN on its behavioural budget could have ecosystem effects that differ between the two saltmarshes studied here.
Collapse
Affiliation(s)
- J D Nuñez
- Instituto de Investigaciones Marinas y Costeras (IIMyC), FCEyN, Universidad Nacional de Mar del Plata-CONICET, CC1260, 7600, Mar del Plata, Provincia de Buenos Aires, Argentina.
| | - V Sbragaglia
- Department of Marine Renewable Resources, Institute of Marine Sciences, 08003, Barcelona, Spain
| | - E D Spivak
- Instituto de Investigaciones Marinas y Costeras (IIMyC), FCEyN, Universidad Nacional de Mar del Plata-CONICET, CC1260, 7600, Mar del Plata, Provincia de Buenos Aires, Argentina
| | - N M Chiaradia
- Instituto de Investigaciones Marinas y Costeras (IIMyC), FCEyN, Universidad Nacional de Mar del Plata-CONICET, CC1260, 7600, Mar del Plata, Provincia de Buenos Aires, Argentina
| | - T A Luppi
- Instituto de Investigaciones Marinas y Costeras (IIMyC), FCEyN, Universidad Nacional de Mar del Plata-CONICET, CC1260, 7600, Mar del Plata, Provincia de Buenos Aires, Argentina
| |
Collapse
|
11
|
Yin S, Bai J, Wang X, Wang X, Zhang G, Jia J, Li X, Liu X. Hydrological connectivity and herbivores control the autochthonous producers of coastal salt marshes. MARINE POLLUTION BULLETIN 2020; 160:111638. [PMID: 32927182 DOI: 10.1016/j.marpolbul.2020.111638] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/16/2019] [Revised: 08/12/2020] [Accepted: 09/01/2020] [Indexed: 06/11/2023]
Abstract
Sea-level rise and overfishing could enhance the strength of hydrological connectivity and the presence of herbivores, resulting in salt marsh loss through physical stress and trophic cascade effects. Our aim was to estimate the effects of these two stresses on autochthonous producers. Survivorship and biomass of Suaeda salsa (S. salsa) were the lowest in areas with high hydrological connectivity, whereas the highest biomass was observed in the areas with moderate connectivity. The biomass of benthic microalgae was higher under low hydrological connectivity and no herbivores. The interactive effects between hydrological connectivity and herbivores on S. salsa but not on benthic microalgae were observed. Herbivores were somewhat (28%) important for the survival of initial S. salsa seedlings, while hydrological connectivity controlled (50%) the biomass of benthic microalgae. Our study highlights that, the autochthonous producers in coastal salt marshes may disappear due to strong hydrological connectivity and the excessive presence of herbivores.
Collapse
Affiliation(s)
- Shuo Yin
- State Key Laboratory of Water Environment Simulation, School of Environment, Beijing Normal University, Beijing 100875, PR China
| | - Junhong Bai
- State Key Laboratory of Water Environment Simulation, School of Environment, Beijing Normal University, Beijing 100875, PR China.
| | - Xin Wang
- State Key Laboratory of Water Environment Simulation, School of Environment, Beijing Normal University, Beijing 100875, PR China
| | - Xinyan Wang
- State Key Laboratory of Water Environment Simulation, School of Environment, Beijing Normal University, Beijing 100875, PR China
| | - Guangliang Zhang
- State Key Laboratory of Water Environment Simulation, School of Environment, Beijing Normal University, Beijing 100875, PR China
| | - Jia Jia
- State Key Laboratory of Water Environment Simulation, School of Environment, Beijing Normal University, Beijing 100875, PR China
| | - Xiaowen Li
- State Key Laboratory of Water Environment Simulation, School of Environment, Beijing Normal University, Beijing 100875, PR China
| | - Xinhui Liu
- State Key Laboratory of Water Environment Simulation, School of Environment, Beijing Normal University, Beijing 100875, PR China
| |
Collapse
|
12
|
Bell L, Cuddington K. A burrowing ecosystem engineer positively affects its microbial prey under stressful conditions. Ecol Evol 2019; 9:7704-7711. [PMID: 31346433 PMCID: PMC6635926 DOI: 10.1002/ece3.5324] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/09/2019] [Revised: 04/05/2019] [Accepted: 05/11/2019] [Indexed: 11/14/2022] Open
Abstract
Species that facilitate others under stressful conditions are often ecosystem engineers: organisms that modify or create physical habitat.However, the net effect of an engineering species on another depends on both the magnitude of the direct interactions (e.g., competition or predation) and the specific environmental context.We used a laboratory system to isolate the trophic and engineering impacts of a predator, the nematode Caenorhabditis remanei, on its prey, Escherichia coli under different levels of environmental stress. We predicted that under stressful surface conditions the nematodes would positively impact their prey by creating burrows which protected the bacteria.Colony plate counts of E. coli indicated that there was a stress-induced change in the net impact of nematodes on bacteria from neutral to positive. Predator engineering in the form of burrowing allowed larger bacteria populations to survive.We conclude that even in a simple two-species system a predator can positively impact prey via ecosystem engineering.
Collapse
Affiliation(s)
- Laura Bell
- Department of BiologyUniversity of WaterlooWaterlooOntarioCanada
| | - Kim Cuddington
- Department of BiologyUniversity of WaterlooWaterlooOntarioCanada
| |
Collapse
|
13
|
Phillips JS, McCormick AR, Einarsson Á, Grover SN, Ives AR. Spatiotemporal variation in the sign and magnitude of ecosystem engineer effects on lake ecosystem production. Ecosphere 2019. [DOI: 10.1002/ecs2.2760] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/10/2022] Open
Affiliation(s)
- Joseph S. Phillips
- Department of Integrative Biology University of Wisconsin‐Madison Madison Wisconsin 53706 USA
| | - Amanda R. McCormick
- Department of Integrative Biology University of Wisconsin‐Madison Madison Wisconsin 53706 USA
| | - Árni Einarsson
- Mývatn Research Station Skútustaðir IS‐660 Iceland
- Faculty of Life and Environmental Sciences University of Iceland Reykjavik IS‐101 Iceland
| | - Shannon N. Grover
- Department of Integrative Biology University of Wisconsin‐Madison Madison Wisconsin 53706 USA
| | - Anthony R. Ives
- Department of Integrative Biology University of Wisconsin‐Madison Madison Wisconsin 53706 USA
| |
Collapse
|
14
|
Qiu D, Yan J, Ma X, Luo M, Wang Q, Cui B. Microtopographical modification by a herbivore facilitates the growth of a coastal saltmarsh plant. MARINE POLLUTION BULLETIN 2019; 140:431-442. [PMID: 30803664 DOI: 10.1016/j.marpolbul.2019.01.066] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/30/2018] [Revised: 01/20/2019] [Accepted: 01/30/2019] [Indexed: 06/09/2023]
Abstract
Increasing evidence shows that herbivores can facilitate plant growth and maintain the resistance of plant communities to trophic consumption in a variety of ecosystems. However, the positive effects of herbivores on annual saltmarsh plants in coastal ecosystems are relatively understudied. In this study, field investigations and manipulative experiments were conducted to explore whether and how microtopographical modification by the herbivorous crab Helice tientsinensis stimulates the growth of the saltmarsh plant Suaeda salsa. Results showed that, despite grazing on S. salsa, H. tientsinensis can promote density, total biomass, average plant height, average root length, and average biomass through burrowing-generated concave-convex microtopography, which can improve the edaphic environment (decreased soil hardness and salinity, and increased soil moisture content, oxidation-reduction potential, and carbon and nitrogen content), and provide plants more clustered growth opportunities that could facilitate positive intraspecific plant interactions. This study can provide scientific guidance for ecosystem restoration in coastal intertidal saltmarshes.
Collapse
Affiliation(s)
- Dongdong Qiu
- School of Environment, State Key Laboratory of Water Environment Simulation, Beijing Normal University, Beijing 100875, China
| | - Jiaguo Yan
- School of Environment, State Key Laboratory of Water Environment Simulation, Beijing Normal University, Beijing 100875, China
| | - Xu Ma
- School of Environment, State Key Laboratory of Water Environment Simulation, Beijing Normal University, Beijing 100875, China
| | - Meng Luo
- School of Environment, State Key Laboratory of Water Environment Simulation, Beijing Normal University, Beijing 100875, China
| | - Qing Wang
- School of Environment, State Key Laboratory of Water Environment Simulation, Beijing Normal University, Beijing 100875, China
| | - Baoshan Cui
- School of Environment, State Key Laboratory of Water Environment Simulation, Beijing Normal University, Beijing 100875, China.
| |
Collapse
|
15
|
O’Brien AM, Sawers RJH, Ross-Ibarra J, Strauss SY. Evolutionary Responses to Conditionality in Species Interactions across Environmental Gradients. Am Nat 2018; 192:715-730. [DOI: 10.1086/700118] [Citation(s) in RCA: 18] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/03/2022]
|
16
|
Velez P, Espinosa-Asuar L, Figueroa M, Gasca-Pineda J, Aguirre-von-Wobeser E, Eguiarte LE, Hernandez-Monroy A, Souza V. Nutrient Dependent Cross-Kingdom Interactions: Fungi and Bacteria From an Oligotrophic Desert Oasis. Front Microbiol 2018; 9:1755. [PMID: 30131780 PMCID: PMC6090137 DOI: 10.3389/fmicb.2018.01755] [Citation(s) in RCA: 23] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/31/2018] [Accepted: 07/13/2018] [Indexed: 11/30/2022] Open
Abstract
Microbial interactions play a key role in ecosystem functioning, with nutrient availability as an important determinant. Although phylogenetically distant bacteria and fungi commonly co-occur in nature, information on their cross-kingdom interactions under unstable, extreme environments remains poor. Hence, the aims of this work were to evaluate potential in vitro interactions among fungi and bacteria isolated from a phosphorous oligotrophic aquatic system in the Cuatro Ciénegas Basin, Mexico, and to test the nutrients-based shifts. We assessed growth changes in bacteria (Aeromonas and Vibrio) and fungi (Coprinellus micaceus, Cladosporium sp., and Aspergillus niger) on co-cultures in relation to monocultures under diverse nutrient scenarios on Petri dishes. Interactions were explored using a network analysis, and a metabolome profiling for specific taxa. We identified nutrient-dependent patterns, as beneficial interactions dominated in low-nutrients media and antagonistic interactions dominated in rich media. This suggests that cross-kingdom synergistic interactions might favor microbial colonization and growth under low nutrient conditions, representing an adaptive trait to oligotrophic environments. Moreover, our findings agree with the stress-gradient hypothesis, since microbial interactions shifted from competition to cooperation as environmental stress (expressed as low nutrients) increased. At a functional level consistent differences were detected in the production of secondary metabolites, agreeing with plate bioassays. Our results based on culture experiments, provides evidence to understand the complexity of microbial dynamics and survival in phosphorous-depleted environments.
Collapse
Affiliation(s)
- Patricia Velez
- Laboratorio de Evolución Molecular y Experimental, Instituto de Ecología, Departamento de Ecología Evolutiva, Universidad Nacional Autónoma de México, Mexico City, Mexico
| | - Laura Espinosa-Asuar
- Laboratorio de Evolución Molecular y Experimental, Instituto de Ecología, Departamento de Ecología Evolutiva, Universidad Nacional Autónoma de México, Mexico City, Mexico
| | - Mario Figueroa
- Laboratorio 125-E, Facultad de Química, Departamento de Farmacia, Universidad Nacional Autónoma de México, Mexico City, Mexico
| | - Jaime Gasca-Pineda
- Laboratorio de Evolución Molecular y Experimental, Instituto de Ecología, Departamento de Ecología Evolutiva, Universidad Nacional Autónoma de México, Mexico City, Mexico
| | | | - Luis E. Eguiarte
- Laboratorio de Evolución Molecular y Experimental, Instituto de Ecología, Departamento de Ecología Evolutiva, Universidad Nacional Autónoma de México, Mexico City, Mexico
| | - Abril Hernandez-Monroy
- Laboratorio de Evolución Molecular y Experimental, Instituto de Ecología, Departamento de Ecología Evolutiva, Universidad Nacional Autónoma de México, Mexico City, Mexico
| | - Valeria Souza
- Laboratorio de Evolución Molecular y Experimental, Instituto de Ecología, Departamento de Ecología Evolutiva, Universidad Nacional Autónoma de México, Mexico City, Mexico
| |
Collapse
|
17
|
Importance of AM fungi and local adaptation in plant response to environmental change: Field evidence at contrasting elevations. FUNGAL ECOL 2018. [DOI: 10.1016/j.funeco.2018.04.006] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/23/2022]
|
18
|
Angelini C, van Montfrans SG, Hensel MJS, He Q, Silliman BR. The importance of an underestimated grazer under climate change: how crab density, consumer competition, and physical stress affect salt marsh resilience. Oecologia 2018; 187:205-217. [DOI: 10.1007/s00442-018-4112-8] [Citation(s) in RCA: 24] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/03/2017] [Accepted: 03/12/2018] [Indexed: 11/29/2022]
|
19
|
Filazzola A, Liczner AR, Westphal M, Lortie CJ. The effect of consumer pressure and abiotic stress on positive plant interactions are mediated by extreme climatic events. THE NEW PHYTOLOGIST 2018; 217:140-150. [PMID: 28944475 DOI: 10.1111/nph.14778] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/29/2017] [Accepted: 07/30/2017] [Indexed: 06/07/2023]
Abstract
Environmental extremes resulting from a changing climate can have profound implications for plant interactions in desert communities. Positive interactions can buffer plant communities from abiotic stress and consumer pressure caused by climatic extremes, but limited research has explored this empirically. We tested the hypothesis that the mechanism of shrub facilitation on an annual plant community can change with precipitation extremes in deserts. During years of extreme drought and above-average rainfall in a desert, we measured plant interactions and biomass while manipulating a soil moisture gradient and reducing consumer pressure. Shrubs facilitated the annual plant community at all levels of soil moisture through reductions in microclimatic stress in both years and herbivore protection in the wet year only. Shrub facilitation and the high rainfall year contributed to the dominance of a competitive annual species in the plant community. Precipitation patterns in deserts determine the magnitude and type of facilitation mechanisms. Moreover, shrub facilitation mediates the interspecific competition within the associated annual community between years with different rainfall amounts. Examining multiple drivers during extreme climate events is a challenging area of research, but it is a necessary consideration given forecasts predicting that these events will increase in frequency and magnitude.
Collapse
Affiliation(s)
- Alessandro Filazzola
- Department of Biology, York University, 4700 Keele St, Toronto, ON, M3J 1P3, Canada
| | - Amanda Rae Liczner
- Department of Biology, York University, 4700 Keele St, Toronto, ON, M3J 1P3, Canada
| | - Michael Westphal
- US Bureau of Land Management, Central Coast Field Office, 940 2nd Avenue, Hollister, CA, 93933, USA
| | - Christopher J Lortie
- Department of Biology, York University, 4700 Keele St, Toronto, ON, M3J 1P3, Canada
| |
Collapse
|
20
|
Lathlean JA, McQuaid CD. Biogeographic Variability in the Value of Mussel Beds as Ecosystem Engineers on South African Rocky Shores. Ecosystems 2016. [DOI: 10.1007/s10021-016-0041-8] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
|
21
|
Aguilera MA, Valdivia N, Broitman BR. Facilitative Effect of a Generalist Herbivore on the Recovery of a Perennial Alga: Consequences for Persistence at the Edge of Their Geographic Range. PLoS One 2015; 10:e0146069. [PMID: 26716986 PMCID: PMC4696856 DOI: 10.1371/journal.pone.0146069] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/17/2015] [Accepted: 12/11/2015] [Indexed: 11/22/2022] Open
Abstract
Understanding the impacts of consumers on the abundance, growth rate, recovery and persistence of their resources across their distributional range can shed light on the role of trophic interactions in determining species range shifts. Here, we examined if consumptive effects of the intertidal grazer Scurria viridula positively influences the abundance and recovery from disturbances of the alga Mazzaella laminarioides at the edge of its geographic distributions in northern-central Chilean rocky shores. Through field experiments conducted at a site in the region where M. laminarioides overlaps with the polar range edge of S. viridula, we estimated the effects of grazing on different life stages of M. laminarioides. We also used long-term abundance surveys conducted across ~700 km of the shore to evaluate co-occurrence patterns of the study species across their range overlap. We found that S. viridula had positive net effects on M. laminarioides by increasing its cover and re-growth from perennial basal crusts. Probability of occurrence of M. laminarioides increased significantly with increasing density of S. viridula across the range overlap. The negative effect of S. viridula on the percentage cover of opportunistic green algae—shown to compete for space with corticated algae—suggests that competitive release may be part of the mechanism driving the positive effect of the limpet on the abundance and recovery from disturbance of M. laminarioides. We suggest that grazer populations contribute to enhance the abundance of M. laminarioides, facilitating its recolonization and persistence at its distributional range edge. Our study highlights that indirect facilitation can determine the recovery and persistence of a resource at the limit of its distribution, and may well contribute to the ecological mechanisms governing species distributions and range shifts.
Collapse
Affiliation(s)
- Moisés A. Aguilera
- Centro de Estudios Avanzados en Zonas Áridas (CEAZA), Universidad Católica del Norte, Ossandón 877, Coquimbo, Chile
- * E-mail:
| | - Nelson Valdivia
- Instituto de Ciencias Marinas y Limnológicas, Facultad de Ciencias, Universidad Austral de Chile, Campus Isla Teja s/n,Valdivia, Chile
| | - Bernardo R. Broitman
- Centro de Estudios Avanzados en Zonas Áridas (CEAZA), Universidad Católica del Norte, Ossandón 877, Coquimbo, Chile
| |
Collapse
|
22
|
Zheng S, Li W, Lan Z, Ren H, Wang K. Functional trait responses to grazing are mediated by soil moisture and plant functional group identity. Sci Rep 2015; 5:18163. [PMID: 26655858 PMCID: PMC4676060 DOI: 10.1038/srep18163] [Citation(s) in RCA: 30] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/30/2015] [Accepted: 11/13/2015] [Indexed: 12/03/2022] Open
Abstract
Abundant evidence has shown that grazing alters plant functional traits, community structure and ecosystem functioning of grasslands. Few studies, however, have tested how plant responses to grazing are mediated by resource availability and plant functional group identity. We examined the effects of grazing on functional traits across a broad range of species along a soil moisture gradient in Inner Mongolia grassland. Our results showed that trait syndromes of plant size (individual biomass) and shoot growth (leaf N content and leaf density) distinguished plant species responses to grazing. The effects of grazing on functional traits were mediated by soil moisture and dependent on functional group identity. For most species, grazing decreased plant height but increased leaf N and specific leaf area (SLA) along the moisture gradient. Grazing enhanced the community-weighted attributes (leaf NCWM and SLACWM), which were triggered mainly by the positive trait responses of annuals and biennials and perennial grasses, and increased relative abundance of perennial forbs. Our results suggest that grazing-induced species turnover and increased intraspecific trait variability are two drivers for the observed changes in community weighted attributes. The dominant perennial bunchgrasses exhibited mixed tolerance-resistance strategies to grazing and mixed acquisitive-conservative strategies in resource utilization.
Collapse
Affiliation(s)
- Shuxia Zheng
- State Key Laboratory of Vegetation and Environmental Change, Institute of Botany, Chinese Academy of Sciences, Beijing 100093, China
| | - Wenhuai Li
- State Key Laboratory of Vegetation and Environmental Change, Institute of Botany, Chinese Academy of Sciences, Beijing 100093, China
| | - Zhichun Lan
- State Key Laboratory of Vegetation and Environmental Change, Institute of Botany, Chinese Academy of Sciences, Beijing 100093, China
| | - Haiyan Ren
- State Key Laboratory of Vegetation and Environmental Change, Institute of Botany, Chinese Academy of Sciences, Beijing 100093, China
| | - Kaibo Wang
- State Key Laboratory of Soil Erosion and Dryland Farming on the Loess Plateau, Institute of Soil and Water Conservation, Chinese Academy of Sciences, Yangling 712100 Shaanxi, China
| |
Collapse
|
23
|
Tamburello L, Maggi E, Benedetti-Cecchi L, Bellistri G, Rattray AJ, Ravaglioli C, Rindi L, Roberts J, Bulleri F. Variation in the impact of non-native seaweeds along gradients of habitat degradation: a meta-analysis and an experimental test. OIKOS 2015. [DOI: 10.1111/oik.02197] [Citation(s) in RCA: 17] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/09/2023]
Affiliation(s)
- Laura Tamburello
- Dipto di Biologia; Univ. of Pisa, CoNISMa; via Derna 1 IT-56126 Pisa Italy
| | - Elena Maggi
- Dipto di Biologia; Univ. of Pisa, CoNISMa; via Derna 1 IT-56126 Pisa Italy
| | | | - Giuseppe Bellistri
- Dipto di Biologia; Univ. of Pisa, CoNISMa; via Derna 1 IT-56126 Pisa Italy
| | - Alex James Rattray
- Dipto di Biologia; Univ. of Pisa, CoNISMa; via Derna 1 IT-56126 Pisa Italy
| | - Chiara Ravaglioli
- Dipto di Biologia; Univ. of Pisa, CoNISMa; via Derna 1 IT-56126 Pisa Italy
| | - Luca Rindi
- Dipto di Biologia; Univ. of Pisa, CoNISMa; via Derna 1 IT-56126 Pisa Italy
| | - Jason Roberts
- Marine Geospatial Ecology Laboratory, Nicholas School of the Environment, Duke Univ.; Durham NC 27708 USA
| | - Fabio Bulleri
- Dipto di Biologia; Univ. of Pisa, CoNISMa; via Derna 1 IT-56126 Pisa Italy
| |
Collapse
|
24
|
Louthan AM, Doak DF, Goheen JR, Palmer TM, Pringle RM. Mechanisms of plant-plant interactions: concealment from herbivores is more important than abiotic-stress mediation in an African savannah. Proc Biol Sci 2014; 281:20132647. [PMID: 24523267 DOI: 10.1098/rspb.2013.2647] [Citation(s) in RCA: 23] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/12/2022] Open
Abstract
Recent work on facilitative plant-plant interactions has emphasized the importance of neighbours' amelioration of abiotic stress, but the facilitative effects of neighbours in reducing plant apparency to herbivores have received less attention. Whereas theory on stress reduction predicts that competition should be more important in less stressful conditions, with facilitation becoming more important in harsh environments, apparency theory suggests that facilitation should be greater in the presence of herbivores, where it is disadvantageous to be conspicuous regardless of abiotic stress level. We tested the relative strength of neighbours' stress reduction versus apparency reduction on survival, growth, reproduction and lifetime fitness of Hibiscus meyeri, a common forb in central Kenya, using neighbour removals conducted inside and outside large-herbivore exclosures replicated in arid and mesic sites. In the absence of herbivores, neighbours competed with H. meyeri in mesic areas and facilitated H. meyeri in arid areas, as predicted by stress-reduction mechanisms. By contrast, neighbours facilitated H. meyeri in the presence of herbivory, regardless of aridity level, consistent with plant apparency. Our results show that the facilitative effects arising from plant apparency are stronger than the effects arising from abiotic stress reduction in this system, suggesting that plant-apparency effects may be particularly important in systems with extant large-herbivore communities.
Collapse
Affiliation(s)
- Allison M Louthan
- Environmental Studies Program, University of Colorado at Boulder, , Boulder, CO 80309, USA, Mpala Research Centre, , PO Box 555, Nanyuki 10400, Kenya, Program in Ecology, Department of Botany, University of Wyoming, , Laramie, WY 82070, USA, Program in Ecology, Department of Zoology and Physiology, University of Wyoming, , Laramie, WY 82070, USA, Department of Biology, University of Florida, , Gainesville, FL 32611, USA, Department of Ecology and Evolutionary Biology, Princeton University, , Princeton, NJ 08544, USA
| | | | | | | | | |
Collapse
|
25
|
Donadi S, Westra J, Weerman EJ, van der Heide T, van der Zee EM, van de Koppel J, Olff H, Piersma T, van der Veer HW, Eriksson BK. Non-trophic Interactions Control Benthic Producers on Intertidal Flats. Ecosystems 2013. [DOI: 10.1007/s10021-013-9686-8] [Citation(s) in RCA: 31] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
|
26
|
Li H, Colica G, Wu PP, Li D, Rossi F, De Philippis R, Liu Y. Shifting species interaction in soil microbial community and its influence on ecosystem functions modulating. MICROBIAL ECOLOGY 2013; 65:700-8. [PMID: 23299348 DOI: 10.1007/s00248-012-0171-2] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/09/2012] [Accepted: 12/17/2012] [Indexed: 05/07/2023]
Abstract
The supportive and negative evidence for the stress gradient hypothesis (SGH) led to an ongoing debate among ecologists and called for new empirical and theoretical work. In this study, we took various biological soil crust (BSCs) samples along a spatial gradient with four environmental stress levels to examine the fitness of SGH in microbial interactions and evaluate its influence on biodiversity-function relationships in BSCs. A new assessment method of species interactions within hard-cultured invisible soil community was employed, directly based on denaturing gradient gel electrophoresis fingerprint images. The results showed that biotic interactions in soil phototroph community dramatically shifted from facilitation to dominant competition with the improvement of microhabitats. It offered new evidence, which presented a different perspective on the hypothesis that the relative importance of facilitation and competition varies inversely along the gradient of abiotic stress. The path analysis indicated that influence of biotic interactions (r = 0.19, p < 0.05) on ecosystem functions is lower than other community properties (r = 0.62, p < 0.001), including soil moisture, crust coverage, and biodiversity. Furthermore, the correlation between species interactions and community properties was non-significant with low negative influence (r = -0.27, p > 0.05). We demonstrate that the inversion of biotic interaction as a response to the gradient of abiotic stresses existed not only in the visible plant community but also in the soil microbial community.
Collapse
Affiliation(s)
- Hua Li
- State Key Laboratory of Freshwater Ecology and Biotechnology, Institute of Hydrobiology, Chinese Academy of Sciences, Wuhan, China
| | | | | | | | | | | | | |
Collapse
|
27
|
Barrio IC, Hik DS, Bueno CG, Cahill JF. Extending the stress-gradient hypothesis - is competition among animals less common in harsh environments? OIKOS 2012. [DOI: 10.1111/j.1600-0706.2012.00355.x] [Citation(s) in RCA: 38] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/26/2022]
|
28
|
Laiolo P. From inter-specific behavioural interactions to species distribution patterns along gradients of habitat heterogeneity. Oecologia 2012; 171:207-15. [PMID: 22806401 DOI: 10.1007/s00442-012-2392-y] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/05/2012] [Accepted: 06/03/2012] [Indexed: 10/28/2022]
Abstract
The strength of the behavioural processes associated with competitor coexistence may vary when different physical environments, and their biotic communities, come into contact, although empirical evidence of how interference varies across gradients of environmental complexity is still scarce in vertebrates. Here, I analyse how behavioural interactions and habitat selection regulate the local distribution of steppeland larks (Alaudidae) in a gradient from simple to heterogeneous agricultural landscapes in Spain, using crested lark Galerida cristata and Thekla lark G. theklae as study models. Galerida larks significantly partitioned by habitat but frequently co-occurred in heterogeneous environments. Irrespective of habitat divergence, however, the local densities of the two larks were negatively correlated, and the mechanisms beyond this pattern were investigated by means of playback experiments. When simulating the intrusion of the congener by broadcasting the species territorial calls, both larks responded with an aggressive response as intense with respect to warning and approach behaviour as when responding to the intrusion of a conspecific. However, birds promptly responded to playbacks only when congener territories were nearby, a phenomenon that points to learning as the mechanisms through which individuals finely tune their aggressive responses to the local competition levels. Heterospecifics occurred in closer proximity in diverse agro-ecosystems, possibly because of more abundant or diverse resources, and here engage in antagonistic interactions. The drop of species diversity associated with agricultural homogenisation is therefore likely to also bring about the disappearance of the behavioural repertoires associated with species interactions.
Collapse
Affiliation(s)
- Paola Laiolo
- Research Unit of Biodiversity (CSIC, UO, PA), Oviedo University, Campus de Mieres, Mieres, Spain.
| |
Collapse
|
29
|
Thrush SF, Hewitt JE, Lohrer AM. Interaction networks in coastal soft-sediments highlight the potential for change in ecological resilience. ECOLOGICAL APPLICATIONS : A PUBLICATION OF THE ECOLOGICAL SOCIETY OF AMERICA 2012; 22:1213-1223. [PMID: 22827129 DOI: 10.1890/11-1403.1] [Citation(s) in RCA: 25] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/01/2023]
Abstract
Recent studies emphasize the role of indirect relationships and feedback loops in maintaining ecosystem resilience. Environmental changes that impact on the organisms involved in these processes have the potential to initiate threshold responses and fundamentally shift the interactions within an ecosystem. However, empirical studies are hindered by the difficulty of designing appropriate manipulative experiments to capture this complexity. Here we employ structural equation modeling to define and test the architecture of ecosystem interaction networks. Using survey data from 19 estuaries we investigate the interactions between biological (abundance of large bioturbating macrofauna, microphytobenthos, and detrital matter) and physical (sediment grain size) processes. We assess the potential for abrupt changes in the architecture of the network and the strength of interactions to occur across environmental gradients. Our analysis identified a potential threshold in the relationship between sediment mud content and benthic chlorophyll a, at -12 microg/g, using quantile regression. Below this threshold, the interaction network involved different variables and fewer feedbacks than above. This approach has potential to improve our empirical understanding of thresholds in ecological systems and our ability to design manipulative experiments that test how and when a threshold will be passed. It can also be used to indicate to resource managers that a particular system has the potential to exhibit threshold responses to environmental change, emphasizing precautionary management and facilitating a better understanding of how persistent multiple stressors threaten the resilience and long-term use of natural ecosystems.
Collapse
Affiliation(s)
- S F Thrush
- National Institute of Water and Atmospheric Research, P.O. Box 11-115, Hamilton 3251, New Zealand.
| | | | | |
Collapse
|
30
|
Vale PF, Wilson AJ, Best A, Boots M, Little TJ. Epidemiological, evolutionary, and coevolutionary implications of context-dependent parasitism. Am Nat 2011; 177:510-21. [PMID: 21460572 DOI: 10.1086/659002] [Citation(s) in RCA: 83] [Impact Index Per Article: 6.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/04/2022]
Abstract
Abstract Victims of infection are expected to suffer increasingly as parasite population growth increases. Yet, under some conditions, faster-growing parasites do not appear to cause more damage, and infections can be quite tolerable. We studied these conditions by assessing how the relationship between parasite population growth and host health is sensitive to environmental variation. In experimental infections of the crustacean Daphnia magna and its bacterial parasite Pasteuria ramosa, we show how easily an interaction can shift from a severe interaction, that is, when host fitness declines substantially with each unit of parasite growth, to a tolerable relationship by changing only simple environmental variables: temperature and food availability. We explored the evolutionary and epidemiological implications of such a shift by modeling pathogen evolution and disease spread under different levels of infection severity and found that environmental shifts that promote tolerance ultimately result in populations harboring more parasitized individuals. We also find that the opportunity for selection, as indicated by the variance around traits, varied considerably with the environmental treatment. Thus, our results suggest two mechanisms that could underlie coevolutionary hotspots and coldspots: spatial variation in tolerance and spatial variation in the opportunity for selection.
Collapse
Affiliation(s)
- Pedro F Vale
- Institute of Evolutionary Biology, School of Biological Sciences, University of Edinburgh, Ashworth Labs, West Mains Road, Edinburgh, Scotland, United Kingdom.
| | | | | | | | | |
Collapse
|
31
|
Daleo P, Alberti J, Iribarne O. Crab herbivory regulates re-colonization of disturbed patches in a southwestern Atlantic salt marsh. OIKOS 2011. [DOI: 10.1111/j.1600-0706.2010.19202.x] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/26/2022]
|
32
|
IDASZKIN YANINAL, BORTOLUS ALEJANDRO, BOUZA PABLOJ. Ecological processes shaping Central Patagonian salt marsh landscapes. AUSTRAL ECOL 2011. [DOI: 10.1111/j.1442-9993.2010.02117.x] [Citation(s) in RCA: 16] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/01/2022]
|