{"title":"Frequency of association: a key indicator for assessing livestock grazing effects on dryland plant interactions, applicable in restoration","authors":"Mariana Tadey, Yamila Ivon Pelliza, Anahí Rocío Fernandez","doi":"10.1111/rec.14275","DOIUrl":null,"url":null,"abstract":"In arid ecosystems, vegetation patches promote biological activity and ecosystem functioning through species interactions that mitigate adverse environmental impacts. However, overgrazing disrupts those interactions, contributing to desertification. We investigated livestock influence on spatial vegetation patterns through the modification of the frequency and type of associations (i.e. number of associated species within a vegetation patch) among types of successional species (i.e. early, intermediate, and late). We studied vegetation in nine rangelands with varying stocking rates (treatments) within the Monte Desert region. We postulated three hypotheses: (1) Grazing simplifies community structure, increasing the frequency of isolated individuals and reducing the association diversity among plant species; (2) competition between plants favors the associations among species with different ecological niche requirements, reducing competition, enhancing facilitation, and regulating the association frequency among species; (3) grazing modifies plant competition and patterns of association among species. We found that with increasing stocking rates, the frequency of isolated individuals increased while association diversity declined. Associations between species with dissimilar niche requirements (e.g. early–late) were more frequent than those with similar needs (e.g. early–early). Livestock grazing modified plant competition, leading to an increased frequency of associations among species with similar requirements. Therefore, the association frequency among types of species in these drylands clearly reflected the degradation process along a grazing gradient, aiding in understanding plant ecological interactions. The association frequency could be implemented as an indicator in diagnostic and monitoring stages of restoration processes.","PeriodicalId":54487,"journal":{"name":"Restoration Ecology","volume":null,"pages":null},"PeriodicalIF":2.8000,"publicationDate":"2024-09-13","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":"0","resultStr":null,"platform":"Semanticscholar","paperid":null,"PeriodicalName":"Restoration Ecology","FirstCategoryId":"93","ListUrlMain":"https://doi.org/10.1111/rec.14275","RegionNum":3,"RegionCategory":"环境科学与生态学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":null,"EPubDate":"","PubModel":"","JCR":"Q2","JCRName":"ECOLOGY","Score":null,"Total":0}
引用次数: 0
Abstract
In arid ecosystems, vegetation patches promote biological activity and ecosystem functioning through species interactions that mitigate adverse environmental impacts. However, overgrazing disrupts those interactions, contributing to desertification. We investigated livestock influence on spatial vegetation patterns through the modification of the frequency and type of associations (i.e. number of associated species within a vegetation patch) among types of successional species (i.e. early, intermediate, and late). We studied vegetation in nine rangelands with varying stocking rates (treatments) within the Monte Desert region. We postulated three hypotheses: (1) Grazing simplifies community structure, increasing the frequency of isolated individuals and reducing the association diversity among plant species; (2) competition between plants favors the associations among species with different ecological niche requirements, reducing competition, enhancing facilitation, and regulating the association frequency among species; (3) grazing modifies plant competition and patterns of association among species. We found that with increasing stocking rates, the frequency of isolated individuals increased while association diversity declined. Associations between species with dissimilar niche requirements (e.g. early–late) were more frequent than those with similar needs (e.g. early–early). Livestock grazing modified plant competition, leading to an increased frequency of associations among species with similar requirements. Therefore, the association frequency among types of species in these drylands clearly reflected the degradation process along a grazing gradient, aiding in understanding plant ecological interactions. The association frequency could be implemented as an indicator in diagnostic and monitoring stages of restoration processes.
期刊介绍:
Restoration Ecology fosters the exchange of ideas among the many disciplines involved with ecological restoration. Addressing global concerns and communicating them to the international research community and restoration practitioners, the journal is at the forefront of a vital new direction in science, ecology, and policy. Original papers describe experimental, observational, and theoretical studies on terrestrial, marine, and freshwater systems, and are considered without taxonomic bias. Contributions span the natural sciences, including ecological and biological aspects, as well as the restoration of soil, air and water when set in an ecological context; and the social sciences, including cultural, philosophical, political, educational, economic and historical aspects. Edited by a distinguished panel, the journal continues to be a major conduit for researchers to publish their findings in the fight to not only halt ecological damage, but also to ultimately reverse it.