1
|
Laber L, Jandowsky A, Frölich K, Heinrich AP, Düring RA, Donath TW, Eichberg C. Dose-dependent in vivo effects of formulated moxidectin on seedling emergence of temperate grassland species. THE SCIENCE OF THE TOTAL ENVIRONMENT 2023; 905:167152. [PMID: 37730042 DOI: 10.1016/j.scitotenv.2023.167152] [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: 07/26/2023] [Revised: 09/05/2023] [Accepted: 09/15/2023] [Indexed: 09/22/2023]
Abstract
Sheep function as effective endozoochorous seed vectors in grasslands. Recent laboratory-based studies showed that this important function can be impaired by macrocyclic lactone anthelmintics, which are used to control parasites and enter into the environment mainly via faeces; however, there is a lack of in vivo studies. We conducted a seed-feeding experiment with sheep that included four temperate grassland species from four different families (Achillea ptarmica, Asteraceae; Agrostis capillaris, Poaceae; Dianthus deltoides, Caryophyllaceae; Plantago lanceolata, Plantaginaceae). A series of three feeding trials was carried out after one of two groups of sheep received a single administration of a common oral formulation of the macrocyclic lactone moxidectin. Faeces were collected to determine seedling emergence rate and emergence timing as well as moxidectin concentration via HPLC. Seedling emergence differed significantly between the anthelmintic-treated sheep and the control group. This impact depended on time of seed uptake after anthelmintic administration. Number of emerging seedlings was significantly reduced (27.1 %) when faeces moxidectin concentrations were high (on average 3153 ng g-1; 1 d post treatment) and significantly increased (up to 68.8 %) when moxidectin concentrations were low (≤86 ng g-1; 7, 14 d pt). Mean emergence time was significantly lowered at low moxidectin concentrations. These results demonstrate dose-related effects of deworming on seedling emergence which might affect endozoochory and eventually plant population dynamics in grasslands.
Collapse
Affiliation(s)
- Lars Laber
- Department of Landscape Ecology, Institute for Natural Resource Conservation, Kiel University, Kiel, Germany.
| | | | - Kai Frölich
- Arche Warder Center for Old and Rare Breeds, Warder, Germany
| | - Andre P Heinrich
- Institute of Soil Science and Soil Conservation, Research Center for Biosystems, Land Use and Nutrition (iFZ), Justus Liebig University, Gießen, Germany
| | - Rolf-Alexander Düring
- Institute of Soil Science and Soil Conservation, Research Center for Biosystems, Land Use and Nutrition (iFZ), Justus Liebig University, Gießen, Germany
| | - Tobias W Donath
- Department of Landscape Ecology, Institute for Natural Resource Conservation, Kiel University, Kiel, Germany
| | - Carsten Eichberg
- Geobotany, Spatial and Environmental Sciences, Trier University, Trier, Germany
| |
Collapse
|
2
|
Popov VN, Syromyatnikov MY, Franceschi C, Moskalev AA, Krutovsky KV, Krutovsky KV. Genetic mechanisms of aging in plants: What can we learn from them? Ageing Res Rev 2022; 77:101601. [PMID: 35278719 DOI: 10.1016/j.arr.2022.101601] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/12/2021] [Revised: 02/03/2022] [Accepted: 03/02/2022] [Indexed: 12/18/2022]
Abstract
Plants hold all records in longevity. Their aging is a complex process. In the presented review, we analyzed published data on various aspects of plant aging with focus on any inferences that could shed a light on aging in animals and help to fight it in human. Plant aging can be caused by many factors, such as telomere depletion, genomic instability, loss of proteostasis, changes in intercellular interaction, desynchronosis, autophagy misregulation, epigenetic changes and others. Plants have developed a number of mechanisms to increase lifespan. Among these mechanisms are gene duplication ("genetic backup"), the active work of telomerases, abundance of meristematic cells, capacity of maintaining the meristems permanently active and continuous activity of phytohormones. Plant aging usually occurs throughout the whole perennial life, but could be also seasonal senescence. Study of causes for seasonal aging can also help to uncover the mechanisms of plant longevity. The influence of different factors such as microbiome communities, glycation, alternative oxidase activity, mitochondrial dysfunction on plant longevity was also reviewed. Adaptive mechanisms of long-lived plants are considered. Further comparative study of the mechanisms underlying longevity of plants is necessary. This will allow us to reach a potentially new level of understanding of the aging process of plants.
Collapse
|
3
|
Ulrich W, Olszewski P, Puchałka R, Sewerniak P, Koprowski M. Inter‐ and intraspecific spatial distributions, spatial segregation by dominants and emergent neutrality in understorey plants. OIKOS 2021. [DOI: 10.1111/oik.08269] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Affiliation(s)
- Werner Ulrich
- Dept of Ecology and Biogeography, Nicolaus Copernicus Univ.Toruń Poland
| | - Piotr Olszewski
- Dept of Ecology and Biogeography, Nicolaus Copernicus Univ.Toruń Poland
| | - Radosław Puchałka
- Dept of Ecology and Biogeography, Nicolaus Copernicus Univ.Toruń Poland
| | - Piotr Sewerniak
- Dept of Soil Science and Landscape Management, Nicolaus Copernicus Univ.Toruń Poland
| | - Marcin Koprowski
- Dept of Ecology and Biogeography, Nicolaus Copernicus Univ.Toruń Poland
| |
Collapse
|
4
|
|
5
|
Martyn TE, Stouffer DB, Godoy O, Bartomeus I, Pastore AI, Mayfield MM. Identifying "Useful" Fitness Models: Balancing the Benefits of Added Complexity with Realistic Data Requirements in Models of Individual Plant Fitness. Am Nat 2021; 197:415-433. [PMID: 33755538 DOI: 10.1086/713082] [Citation(s) in RCA: 9] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/04/2022]
Abstract
AbstractDirect species interactions are commonly included in individual fitness models used for coexistence and local diversity modeling. Though widely considered important for such models, direct interactions alone are often insufficient for accurately predicting fitness, coexistence, or diversity outcomes. Incorporating higher-order interactions (HOIs) can lead to more accurate individual fitness models but also adds many model terms, which can quickly result in model overfitting. We explore approaches for balancing the trade-off between tractability and model accuracy that occurs when HOIs are added to individual fitness models. To do this, we compare models parameterized with data from annual plant communities in Australia and Spain, varying in the extent of information included about the focal and neighbor species. The best-performing models for both data sets were those that grouped neighbors based on origin status and life form, a grouping approach that reduced the number of model parameters substantially while retaining important ecological information about direct interactions and HOIs. Results suggest that the specific identity of focal or neighbor species is not necessary for building well-performing fitness models that include HOIs. In fact, grouping neighbors by even basic functional information seems sufficient to maximize model accuracy, an important outcome for the practical use of HOI-inclusive fitness models.
Collapse
|
6
|
Jin LS, Yin D, Fortin MJ, Cadotte MW. The mechanisms generating community phylogenetic patterns change with spatial scale. Oecologia 2020; 193:655-664. [PMID: 32621030 DOI: 10.1007/s00442-020-04695-9] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/14/2019] [Accepted: 06/16/2020] [Indexed: 10/23/2022]
Abstract
Studies that test community assembly hypotheses in observational communities frequently evaluate patterns for plots or entire communities, yet studies that examine assembly patterns across spatial scales show that they are greatly influenced by scale. Here, we test the spatial dependency of patterns of relatedness and plant height for all individual herbaceous plants along five 40-m old-field transects (Southern Ontario, Canada). We identified each individual plant and measured its distance along the transect and its height, and we constructed a molecular phylogeny for all observed species. To uncover the scale at which community phylogenetic and trait similarities shift, we used partial Mantel correlograms and distance-based Moran Eigenvector Maps (dbMEMs). We found that communities shift from significantly overdispersed at relatively smaller scales (i.e., < 15 m) to spatially clustered at larger scales, showing that assembly mechanism influence depends on scale of observation. This pattern was observed for both phylogeny and height, but was the strongest when considering phylogeny only. These results reveal the importance of spatial scale when examining community phylogenetic or trait patterns, where finding support for one assembly mechanism at a single scale does not necessarily mean that other mechanisms are also not important for structuring community composition and diversity.
Collapse
Affiliation(s)
- Lanna S Jin
- Department of Ecology and Evolutionary Biology, University of Toronto, Toronto, Canada
| | - Deyi Yin
- Department of Biological Sciences, University of Toronto at Scarborough, Scarborough, 416-208-5105, Canada
| | - Marie-Josée Fortin
- Department of Ecology and Evolutionary Biology, University of Toronto, Toronto, Canada
| | - Marc W Cadotte
- Department of Ecology and Evolutionary Biology, University of Toronto, Toronto, Canada. .,Department of Biological Sciences, University of Toronto at Scarborough, Scarborough, 416-208-5105, Canada.
| |
Collapse
|
7
|
Yılmaz OY, Kavgacı A, Sevgi O, Örtel E, Tecimen HB, Çobanoğlu A, Yeşil İ. Scale-dependent intraspecific competition of Taurus cedar ( Cedrus libani A. Rich.) saplings in the Southern Turkey. Ecol Evol 2019; 9:12802-12812. [PMID: 31788215 PMCID: PMC6875569 DOI: 10.1002/ece3.5757] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/25/2019] [Revised: 09/18/2019] [Accepted: 09/27/2019] [Indexed: 11/10/2022] Open
Abstract
Better understanding of the competitive interaction at the early development stages of the stand is crucial to help schedule silvicultural treatments for young stands and for the better management of the future stands. We used scale-dependent analysis to improve our understanding of sapling dynamics in the pure Taurus cedar (Cedrus libani A. Rich.) stands in Southern Turkey. Using data from nine plots established at the western Taurus Mountains, diameter, height, and crown radii of saplings were compared, and spatial point pattern analyses were performed. We found significant differences for the mean diameter and height, and crown radii of saplings among the plots. Univariate pair correlation function showed that sapling pattern was regular only at small scales (r < 0.4 m) but was predominantly random. Bivariate pair correlation function revealed no evidence of spatial interaction between tall saplings and short saplings. Univariate mark correlation function revealed that strong intraspecific competition was detected at small scales (up to 0.55 m). This distance is reasonable for the juvenile age tending of Taurus cedar saplings and should be under consideration during silvicultural treatments to use the site productivity more efficiently.
Collapse
Affiliation(s)
- Osman Yalçın Yılmaz
- Department of Forest EngineeringFaculty of ForestryIstanbul University‐CerrahpasaIstanbulTurkey
| | - Ali Kavgacı
- Southwest Anatolia Forest Research InstituteAntalyaTurkey
| | - Orhan Sevgi
- Department of Soil Science and EcologyFaculty of ForestryIstanbul University‐CerrahpasaIstanbulTurkey
| | - Erdal Örtel
- Aegean Forestry Research InstituteUrlaTurkey
| | - Hüseyin Barış Tecimen
- Department of Soil Science and EcologyFaculty of ForestryIstanbul University‐CerrahpasaIstanbulTurkey
| | | | - İsmet Yeşil
- Eskişehir Regional Directorate of ForestryEskisehirTurkey
| |
Collapse
|
8
|
Häbel H, Myllymäki M, Pommerening A. New insights on the behaviour of alternative types of individual-based tree models for natural forests. Ecol Modell 2019. [DOI: 10.1016/j.ecolmodel.2019.02.013] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/26/2022]
|
9
|
Schouten OS, Houseman GR. Effect of soil heterogeneity and endogenous processes on plant spatial structure. Ecology 2019; 100:e02837. [PMID: 31330044 DOI: 10.1002/ecy.2837] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 12/03/2018] [Revised: 06/10/2019] [Accepted: 06/17/2019] [Indexed: 11/06/2022]
Abstract
Within communities, organisms potentially self-organize through endogenous processes that create nonrandom spatial structure as they interact with one another or modify the abiotic environment. In contrast, exogenous processes such as environmental heterogeneity or variable immigration are thought to be dominant processes controlling these spatial patterns. Although both endogenous and exogenous processes likely occur, their relative importance is still largely unknown because of limited analytical tools and the lack of experimental evidence, particularly those that address exogenous sources of environmental heterogeneity. Here, we used a soil heterogeneity experiment to examine the relative effect of endogenous and exogenous processes on plant spatial structure after five years of community assembly. Soil heterogeneity was manipulated by splitting the vertical soil profile into three soil-types that were randomly assigned to 40 × 40 cm patches within 2.4 × 2.4 m plots. Homogeneous plots were created by mixing all soils before filling each patch. Thirty-four grassland species were then sown into all plots and allowed to grow for five years after which the location of all plants was mapped using a 5 × 5 cm grid. Results from point-pattern spatial analysis indicated that, even in the absence of soil heterogeneity and with initial seed arrival, spatial structure was primarily generated by endogenous processes. Although soil heterogeneity increased species aggregation at certain scales, most of the spatial structure was created by endogenous processes. These results suggest that endogenous processes may be more important than expected for generating spatial structure and can develop much faster than anticipated.
Collapse
Affiliation(s)
- Olivia S Schouten
- Department of Biological Sciences, Wichita State University, 537 Hubbard Hall, Campus Box 26, 1845 Fairmount Street, Wichita, Kansas, 67260, USA
| | - Gregory R Houseman
- Department of Biological Sciences, Wichita State University, 537 Hubbard Hall, Campus Box 26, 1845 Fairmount Street, Wichita, Kansas, 67260, USA
| |
Collapse
|
10
|
Goldberg DE, Martina JP, Elgersma KJ, Currie WS. Plant Size and Competitive Dynamics along Nutrient Gradients. Am Nat 2017; 190:229-243. [DOI: 10.1086/692438] [Citation(s) in RCA: 24] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/03/2022]
|
11
|
Zhang S, Huang Y, Zang R. The assembly and interactions of tree species in tropical forests based on spatial analysis. Ecosphere 2017. [DOI: 10.1002/ecs2.1903] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/12/2022] Open
Affiliation(s)
- Shuzi Zhang
- Key Laboratory of Forest Ecology and Environment; The State Forestry Administration; Institute of Forest Ecology, Environment and Protection; Chinese Academy of Forestry; Beijing 100091 China
- Co-Innovation Center for Sustainable Forestry in Southern China; Nanjing Forestry University; Nanjing Jiangsu 210037 China
| | - Yunfeng Huang
- Key Laboratory of Forest Ecology and Environment; The State Forestry Administration; Institute of Forest Ecology, Environment and Protection; Chinese Academy of Forestry; Beijing 100091 China
- Co-Innovation Center for Sustainable Forestry in Southern China; Nanjing Forestry University; Nanjing Jiangsu 210037 China
| | - Runguo Zang
- Key Laboratory of Forest Ecology and Environment; The State Forestry Administration; Institute of Forest Ecology, Environment and Protection; Chinese Academy of Forestry; Beijing 100091 China
- Co-Innovation Center for Sustainable Forestry in Southern China; Nanjing Forestry University; Nanjing Jiangsu 210037 China
| |
Collapse
|
12
|
Affiliation(s)
- Eric J. Pedersen
- Dept of Biology; McGill Univ.; Montreal QC Canada
- Center for Limnology; Univ. of Wisconsin-Madison; 680 North Park Street Madison WI 53706 USA
| | | |
Collapse
|
13
|
Nakagawa Y, Yokozawa M, Hara T. Competition among plants can lead to an increase in aggregation of smaller plants around larger ones. Ecol Modell 2015. [DOI: 10.1016/j.ecolmodel.2015.01.014] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/24/2022]
|
14
|
Local density effects on individual production are dynamic: insights from natural stands of a perennial savanna grass. Oecologia 2015; 178:1125-35. [DOI: 10.1007/s00442-015-3291-9] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/02/2014] [Accepted: 03/05/2015] [Indexed: 11/26/2022]
|
15
|
Velázquez J, Garrahan JP, Eichhorn MP. Spatial complementarity and the coexistence of species. PLoS One 2014; 9:e114979. [PMID: 25532018 PMCID: PMC4274010 DOI: 10.1371/journal.pone.0114979] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/27/2014] [Accepted: 11/16/2014] [Indexed: 11/19/2022] Open
Abstract
Coexistence of apparently similar species remains an enduring paradox in ecology. Spatial structure has been predicted to enable coexistence even when population-level models predict competitive exclusion if it causes each species to limit its own population more than that of its competitor. Nevertheless, existing hypotheses conflict with regard to whether clustering favours or precludes coexistence. The spatial segregation hypothesis predicts that in clustered populations the frequency of intra-specific interactions will be increased, causing each species to be self-limiting. Alternatively, individuals of the same species might compete over greater distances, known as heteromyopia, breaking down clusters and opening space for a second species to invade. In this study we create an individual-based model in homogeneous two-dimensional space for two putative sessile species differing only in their demographic rates and the range and strength of their competitive interactions. We fully characterise the parameter space within which coexistence occurs beyond population-level predictions, thereby revealing a region of coexistence generated by a previously-unrecognised process which we term the triadic mechanism. Here coexistence occurs due to the ability of a second generation of offspring of the rarer species to escape competition from their ancestors. We diagnose the conditions under which each of three spatial coexistence mechanisms operates and their characteristic spatial signatures. Deriving insights from a novel metric - ecological pressure - we demonstrate that coexistence is not solely determined by features of the numerically-dominant species. This results in a common framework for predicting, given any pair of species and knowledge of the relevant parameters, whether they will coexist, the mechanism by which they will do so, and the resultant spatial pattern of the community. Spatial coexistence arises from complementary combinations of traits in each species rather than solely through self-limitation.
Collapse
Affiliation(s)
- Jorge Velázquez
- School of Physics & Astronomy, The University of Nottingham, University Park, Nottingham, NG7 2RD, United Kingdom
- Facultad de Ciencias Físico Matemáticas, Universidad Autónoma de Puebla, 72001, Puebla, Pue., México
| | - Juan P. Garrahan
- School of Physics & Astronomy, The University of Nottingham, University Park, Nottingham, NG7 2RD, United Kingdom
| | - Markus P. Eichhorn
- School of Life Sciences, The University of Nottingham, University Park, Nottingham, NG7 2RD, United Kingdom
| |
Collapse
|
16
|
Seifan M, Seifan T, Schiffers K, Jeltsch F, Tielbörger K. Beyond the Competition-Colonization Trade-Off: Linking Multiple Trait Response to Disturbance Characteristics. Am Nat 2013; 181:151-60. [DOI: 10.1086/668844] [Citation(s) in RCA: 17] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/03/2022]
|
17
|
Herben T, Wildová R. Community-level effects of plant traits in a grassland community examined by multispecies model of clonal plant growth. Ecol Modell 2012. [DOI: 10.1016/j.ecolmodel.2011.06.012] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/18/2022]
|
18
|
Can we predict performance and spatial structure of two-species mixtures using only single species information from monocultures? Ecol Modell 2012. [DOI: 10.1016/j.ecolmodel.2011.05.036] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/23/2022]
|
19
|
Porensky LM, Vaughn KJ, Young TP. Can initial intraspecific spatial aggregation increase multi-year coexistence by creating temporal priority? ECOLOGICAL APPLICATIONS : A PUBLICATION OF THE ECOLOGICAL SOCIETY OF AMERICA 2012; 22:927-936. [PMID: 22645821 DOI: 10.1890/11-0818.1] [Citation(s) in RCA: 23] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/01/2023]
Abstract
Both intraspecific spatial aggregation and temporal priority effects have the potential to increase long-term species coexistence. Theory and models suggest that intraspecific aggregation can facilitate coexistence via limited dispersal or asymmetric interaction distances. During community assembly, intraspecific aggregation may also delay interactions between more and less competitive species, thus creating opportunities for priority effects to facilitate longer-term coexistence. Few empirical studies have tested predictions about aggregation and coexistence, especially in the context of community assembly or ecological restoration. We investigated (1) impacts of intraspecific aggregation on the assembly of eight-species communities over three years, (2) the scale dependence of these impacts, and (3) implications for California prairie restoration. We planted eight native species in each of 19, 5 m wide, octagonal plots. Species were either interspersed throughout the plot or aggregated into eight, 2.2-m(2), wedge-shaped, monospecific sectors. Over three years, species diversity declined more quickly in interspersed plots than in aggregated plots. Two species had higher cover or increased more in interspersed than aggregated plots and were identified as "aggressives." Four species had higher cover or increased more in aggregated than interspersed plots and were identified as "subordinates." Within aggregated plots, aggressive species expanded beyond the sector in which they were originally seeded. Cover of aggressive species increased faster and reached higher values in sectors that were adjacent to the originally planted sector, compared to nonadjacent sectors. Cover of aggressive species also increased more and faster near plot centers, compared to plot edges. Areas near plot centers were representative of smaller aggregation patches since species were planted closer to heterospecific neighbors. Two subordinate species maintained higher cover near plot edges than near plot centers. Moreover, two subordinate species maintained higher cover when seeded in sectors farther away from aggressive species. These results suggest that initial intraspecific aggregation can facilitate species coexistence for at least three years, and larger aggregation patches may be more effective than smaller ones in the face of dispersing dominants. The creation of temporal priority effects may represent an underappreciated pathway by which intraspecific aggregation can increase coexistence. Restorationists may be able to maintain more diverse communities by planting in a mosaic of monospecific patches.
Collapse
Affiliation(s)
- Lauren M Porensky
- Department of Plant Sciences and Graduate Group in Ecology, University of California, One Shields Avenue, Davis, California 95616, USA.
| | | | | |
Collapse
|
20
|
Species-specific effects of woody litter on seedling emergence and growth of herbaceous plants. PLoS One 2011; 6:e26505. [PMID: 22028890 PMCID: PMC3197666 DOI: 10.1371/journal.pone.0026505] [Citation(s) in RCA: 22] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/17/2011] [Accepted: 09/28/2011] [Indexed: 11/19/2022] Open
Abstract
The effect of litter on seedling establishment can influence species richness in plant communities. The effect of litter depends on amount, and also on litter type, but relatively little is known about the species-specific effects of litter. We conducted a factorial greenhouse experiment to examine the effect of litter type, using two woody species that commonly co-occur in boreonemoral forest--evergreen spruce (Picea abies), deciduous hazel (Corylus avellana), and a mixture of the two species--and litter amount--shallow (4 mm), deep (12 mm) and leachate--on seedling emergence and biomass of three understorey species. The effect of litter amount on seedling emergence was highly dependent on litter type; while spruce needle litter had a significant negative effect that increased with depth, seedling emergence in the presence of hazel broadleaf litter did not differ from control pots containing no litter. Mixed litter of both species also had a negative effect on seedling emergence that was intermediate compared to the single-species treatments. Spruce litter had a marginally positive (shallow) or neutral effect (deep) on seedling biomass, while hazel and mixed litter treatments had significant positive effects on biomass that increased with depth. We found non-additive effects of litter mixtures on seedling biomass indicating that high quality hazel litter can reduce the negative effects of spruce. Hazel litter does not inhibit seedling emergence; it increases seedling growth, and creates better conditions for seedling growth in mixtures by reducing the suppressive effect of spruce litter, having a positive effect on understorey species richness.
Collapse
|
21
|
Dostál P. Plant competitive interactions and invasiveness: searching for the effects of phylogenetic relatedness and origin on competition intensity. Am Nat 2011; 177:655-67. [PMID: 21508611 DOI: 10.1086/659060] [Citation(s) in RCA: 60] [Impact Index Per Article: 4.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/04/2022]
Abstract
The invasion success of introduced plants is frequently explained as a result of competitive interactions with native flora. Although previous theory and experiments have shown that plants are largely equivalent in their competitive effects on each other, competitive nonequivalence is hypothesized to occur in interactions between native and invasive species. Small overlap in resource use with unrelated native species, improved competitiveness, and production of novel allelochemicals are all believed to contribute to the invasiveness of introduced species. I tested all three assumptions in a common-garden experiment by examining the effect of plant origin and relatedness on competition intensity. Competitive interactions were explored within 12 triplets, each consisting of an invasive species, a native congeneric (or confamilial) species, and a native heterogeneric species that are likely to interact in the field. Plants were grown in pots alone or in pairs and in the absence or the presence of activated carbon to control for allelopathy. I found that competition intensity was not influenced by the relatedness or origin of competing neighbors. Although some exotic species may benefit from size advantages and species-specific effects in competitive interactions, none of the three mechanisms investigated is likely to be a principal driver of their invasiveness.
Collapse
Affiliation(s)
- Petr Dostál
- Institute of Botany, Academy of Sciences of the Czech Republic, Průhonice, Czech Republic.
| |
Collapse
|
22
|
Fibich P, Lepš J. Do biodiversity indices behave as expected from traits of constituent species in simulated scenarios? Ecol Modell 2011. [DOI: 10.1016/j.ecolmodel.2011.04.013] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/17/2022]
|