Pub Date : 2025-03-01DOI: 10.1016/j.ecocom.2025.101116
Carlo Ricotta , Sandrine Pavoine
Functional diversity, redundancy, rarity, and originality (or distinctiveness) are fundamental concepts in ecology and conservation biology. Despite their frequent use, the precise meaning and relationships between these measures are often unclear. This paper aims to provide a comprehensive theoretical framework to elucidate what each of these measures captures and how they interrelate. By integrating traditional community-level diversity metrics with species-level specificity measures derived from fuzzy set theory, we bridge the gap between these concepts. Our framework reveals that while all four measures address distinct aspects of community-level and species-level functional resemblance, they can all be traced back to a common conceptual and formal background. This guide is intended to help ecologists and conservationists understand the meaning of these measures and apply them more effectively in their research and conservation strategies.
{"title":"What do functional diversity, redundancy, rarity, and originality actually measure? A theoretical guide for ecologists and conservationists","authors":"Carlo Ricotta , Sandrine Pavoine","doi":"10.1016/j.ecocom.2025.101116","DOIUrl":"10.1016/j.ecocom.2025.101116","url":null,"abstract":"<div><div>Functional diversity, redundancy, rarity, and originality (or distinctiveness) are fundamental concepts in ecology and conservation biology. Despite their frequent use, the precise meaning and relationships between these measures are often unclear. This paper aims to provide a comprehensive theoretical framework to elucidate what each of these measures captures and how they interrelate. By integrating traditional community-level diversity metrics with species-level specificity measures derived from fuzzy set theory, we bridge the gap between these concepts. Our framework reveals that while all four measures address distinct aspects of community-level and species-level functional resemblance, they can all be traced back to a common conceptual and formal background. This guide is intended to help ecologists and conservationists understand the meaning of these measures and apply them more effectively in their research and conservation strategies.</div></div>","PeriodicalId":50559,"journal":{"name":"Ecological Complexity","volume":"61 ","pages":"Article 101116"},"PeriodicalIF":3.1,"publicationDate":"2025-03-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143529703","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"环境科学与生态学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2025-02-21DOI: 10.1016/j.ecocom.2025.101117
Bapin Mondal , Sayan Mandal , Pankaj Kumar Tiwari , Hao Wang , Pablo Venegas Garcia
Studying plankton systems encompasses different interests, including understanding ecological cycles and developing sustainable strategies in aquaculture research regarding food security. Zooplankton farming is economically valuable, and its production may depend primarily on the availability of phytoplankton and other external food sources. However, diverse factors may affect overall phytoplankton–zooplankton interactions. For example, phytoplankton’s defense mechanisms, such as finding refuge and releasing toxins or low phytoplankton’s sustainable environments, can decrease zooplankton populations. Another critical factor is the adverse effects of pollution on plankton systems, which are more frequently present in water bodies. Still, zooplankton may survive harsh conditions if present pollutants are in low concentrations and external sources, including animal waste, are available. The partial understanding of these trophic interactions depends on initial assumptions, and using stochastic approaches may reduce the gap between deterministic mathematical outcomes and reality. In this work, we have mathematically described a planktonic system under the above assumptions using a deterministic model as well as its stochastic version. Our findings suggest that zooplankton growth is possible under polluted environments by providing them with external food sources, complementing phytoplankton availability. However, in these circumstances, random external environmental factors may cause the phytoplankton population to collapse. Through stochastic numerical experiments, we estimate which possible scenarios are more likely to induce phytoplankton extinction in these plankton systems.
{"title":"Deterministic and stochastic plankton dynamics: Effects of contamination, refuge, and additional food sources","authors":"Bapin Mondal , Sayan Mandal , Pankaj Kumar Tiwari , Hao Wang , Pablo Venegas Garcia","doi":"10.1016/j.ecocom.2025.101117","DOIUrl":"10.1016/j.ecocom.2025.101117","url":null,"abstract":"<div><div>Studying plankton systems encompasses different interests, including understanding ecological cycles and developing sustainable strategies in aquaculture research regarding food security. Zooplankton farming is economically valuable, and its production may depend primarily on the availability of phytoplankton and other external food sources. However, diverse factors may affect overall phytoplankton–zooplankton interactions. For example, phytoplankton’s defense mechanisms, such as finding refuge and releasing toxins or low phytoplankton’s sustainable environments, can decrease zooplankton populations. Another critical factor is the adverse effects of pollution on plankton systems, which are more frequently present in water bodies. Still, zooplankton may survive harsh conditions if present pollutants are in low concentrations and external sources, including animal waste, are available. The partial understanding of these trophic interactions depends on initial assumptions, and using stochastic approaches may reduce the gap between deterministic mathematical outcomes and reality. In this work, we have mathematically described a planktonic system under the above assumptions using a deterministic model as well as its stochastic version. Our findings suggest that zooplankton growth is possible under polluted environments by providing them with external food sources, complementing phytoplankton availability. However, in these circumstances, random external environmental factors may cause the phytoplankton population to collapse. Through stochastic numerical experiments, we estimate which possible scenarios are more likely to induce phytoplankton extinction in these plankton systems.</div></div>","PeriodicalId":50559,"journal":{"name":"Ecological Complexity","volume":"61 ","pages":"Article 101117"},"PeriodicalIF":3.1,"publicationDate":"2025-02-21","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143453809","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"环境科学与生态学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2024-12-30DOI: 10.1016/j.ecocom.2024.101115
Sze-Wing To , Esteban Acevedo-Trejos , Sherwood Lan Smith , Subhendu Chakraborty , Agostino Merico
For decades, ecologists have been intrigued by the paradoxical coexistence of a wide range of phytoplankton types on a seemingly limited number of resources. The interactions between environmental conditions and trade-offs emerging from eco-physiological traits of phytoplankton are typically proposed to explain coexistence. The number of coexisting types over ecological time scales reflects what we call here ‘exclusion patterns’, that is, the temporal removal of certain phytoplankton types due to competition. Despite many observational and mathematical modelling efforts over the last two decades, we still know surprisingly little, in quantitative terms, about how the interplay of nutrient regimes and specific zooplankton grazing strategies affects the exclusion patterns of competing phytoplankton types. Phytoplankton types can be distinguished according to many different traits. Among various morphological traits, phytoplankton cell size is considered one of the most meaningful in explaining crucial eco-physiological processes, including nutrient uptake and zooplankton grazing. Here we use a size-based plankton model to investigate exclusion patterns of phytoplankton size classes over ecological time scales and under varying environmental conditions. We performed numerical experiments under different allometric scaling relationships, different combinations of specialist and generalist grazing strategies, different inorganic nutrient regimes, and different mixing frequencies. We quantified exclusion patterns by using two metrics: (1) coexistence, defined here as the average number of size classes present over the first 30 days of the simulations, and (2) exclusion time scale, defined here as the time required to outcompete 80 % of the size classes present in the system at the beginning of the simulations. Under low nutrient regimes, we found that the impact of grazing on the exclusion patterns of phytoplankton was almost negligible. Under high nutrient regimes, different exclusion patterns emerged depending on the grazing strategy. When the community of zooplankton was dominated by generalist grazers, we found higher coexistence and longer exclusion time scales of phytoplankton size classes than when the community of zooplankton was dominated by specialist grazers. We further found that the combined effects of grazing strategies and allometric relationships on the size structure of the phytoplankton community were significant and non-trivial. We thus argue that plankton models disregarding these processes may miss relevant drivers of phytoplankton community assembly and trait diversity.
{"title":"Ecological and environmental factors influencing exclusion patterns of phytoplankton size classes in lake systems","authors":"Sze-Wing To , Esteban Acevedo-Trejos , Sherwood Lan Smith , Subhendu Chakraborty , Agostino Merico","doi":"10.1016/j.ecocom.2024.101115","DOIUrl":"10.1016/j.ecocom.2024.101115","url":null,"abstract":"<div><div>For decades, ecologists have been intrigued by the paradoxical coexistence of a wide range of phytoplankton types on a seemingly limited number of resources. The interactions between environmental conditions and trade-offs emerging from eco-physiological traits of phytoplankton are typically proposed to explain coexistence. The number of coexisting types over ecological time scales reflects what we call here ‘exclusion patterns’, that is, the temporal removal of certain phytoplankton types due to competition. Despite many observational and mathematical modelling efforts over the last two decades, we still know surprisingly little, in quantitative terms, about how the interplay of nutrient regimes and specific zooplankton grazing strategies affects the exclusion patterns of competing phytoplankton types. Phytoplankton types can be distinguished according to many different traits. Among various morphological traits, phytoplankton cell size is considered one of the most meaningful in explaining crucial eco-physiological processes, including nutrient uptake and zooplankton grazing. Here we use a size-based plankton model to investigate exclusion patterns of phytoplankton size classes over ecological time scales and under varying environmental conditions. We performed numerical experiments under different allometric scaling relationships, different combinations of specialist and generalist grazing strategies, different inorganic nutrient regimes, and different mixing frequencies. We quantified exclusion patterns by using two metrics: (1) coexistence, defined here as the average number of size classes present over the first 30 days of the simulations, and (2) exclusion time scale, defined here as the time required to outcompete 80 % of the size classes present in the system at the beginning of the simulations. Under low nutrient regimes, we found that the impact of grazing on the exclusion patterns of phytoplankton was almost negligible. Under high nutrient regimes, different exclusion patterns emerged depending on the grazing strategy. When the community of zooplankton was dominated by generalist grazers, we found higher coexistence and longer exclusion time scales of phytoplankton size classes than when the community of zooplankton was dominated by specialist grazers. We further found that the combined effects of grazing strategies and allometric relationships on the size structure of the phytoplankton community were significant and non-trivial. We thus argue that plankton models disregarding these processes may miss relevant drivers of phytoplankton community assembly and trait diversity.</div></div>","PeriodicalId":50559,"journal":{"name":"Ecological Complexity","volume":"61 ","pages":"Article 101115"},"PeriodicalIF":3.1,"publicationDate":"2024-12-30","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143132591","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"环境科学与生态学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2024-11-06DOI: 10.1016/j.ecocom.2024.101107
Bilel Elbetch , Ali Moussaoui
In this paper, we investigate a prey–predator community of fish coexisting in a multi-patches model, where different fishing patches are interconnected through migration terms. Only the predator is caught, while the prey grows logistically on each patch. The main objective of our research is to compare the maximum sustainable yield achieved in two contrasting scenarios: unconnected patches and connected patches with rapid stock movements. We show that the total maximum sustainable yield for the connected patches can be greater than the sum of the maximum sustainable yield on each isolated patch. The analysis of the model allows us to establish the conditions under which one of the two cases is more favorable from the viewpoint of yield. As a result, we provide a complete classification for all possible cases. This valuable information can be used to assist decision-makers in selecting the best management strategy for a particular fishery.
{"title":"Enhancing maximum sustainable yield in a patchy prey–predator environment","authors":"Bilel Elbetch , Ali Moussaoui","doi":"10.1016/j.ecocom.2024.101107","DOIUrl":"10.1016/j.ecocom.2024.101107","url":null,"abstract":"<div><div>In this paper, we investigate a prey–predator community of fish coexisting in a multi-patches model, where different fishing patches are interconnected through migration terms. Only the predator is caught, while the prey grows logistically on each patch. The main objective of our research is to compare the maximum sustainable yield achieved in two contrasting scenarios: unconnected patches and connected patches with rapid stock movements. We show that the total maximum sustainable yield for the connected patches can be greater than the sum of the maximum sustainable yield on each isolated patch. The analysis of the model allows us to establish the conditions under which one of the two cases is more favorable from the viewpoint of yield. As a result, we provide a complete classification for all possible cases. This valuable information can be used to assist decision-makers in selecting the best management strategy for a particular fishery.</div></div>","PeriodicalId":50559,"journal":{"name":"Ecological Complexity","volume":"60 ","pages":"Article 101107"},"PeriodicalIF":3.1,"publicationDate":"2024-11-06","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142593776","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"环境科学与生态学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2024-10-30DOI: 10.1016/j.ecocom.2024.101104
Karl Kästner , Roeland C. van de Vijsel , Daniel Caviedes-Voullième , Christoph Hinz
Spatial patterns of alternating high and low biomass occur in a wide range of ecosystems. Patterns can improve ecosystem productivity and resilience, but the particular effects of patterning depend on their spatial structure. The spatial structure is conventionally classified as either regular, when the patches of biomass are of similar size and are spaced in similar intervals, or irregular. The formation of regular patterns is driven by scale-dependent feedbacks. Models incorporating those feedbacks generate highly regular patterns, while natural patterns appear less regular. This calls for a more nuanced quantification beyond a binary classification. Here, we propose measuring the degree of regularity by the maximum of a pattern’s spectral density, based on the observation that the density of highly regular patterns consists of a narrow and high peak, while the density of highly irregular patterns consists of a low and wide lobe. We rescale the density to make the measure invariant with respect to the characteristic length-scale of a pattern, facilitating the comparison of patterns observed or modelled under different conditions. We demonstrate our method in a metastudy determining the regularity of natural and model-generated patterns depicted in previous studies. We find that natural patterns have an intermediate degree of regularity, resembling random surfaces generated by stochastic processes. We find that conventional deterministic models do not reproduce the intermediate regularity of natural patterns, as they generate patterns which are much more regular and similar to periodic surfaces. We call for appreciating the stochasticity of natural patterns in systems with scale-dependent feedbacks.
{"title":"A scale-invariant method for quantifying the regularity of environmental spatial patterns","authors":"Karl Kästner , Roeland C. van de Vijsel , Daniel Caviedes-Voullième , Christoph Hinz","doi":"10.1016/j.ecocom.2024.101104","DOIUrl":"10.1016/j.ecocom.2024.101104","url":null,"abstract":"<div><div>Spatial patterns of alternating high and low biomass occur in a wide range of ecosystems. Patterns can improve ecosystem productivity and resilience, but the particular effects of patterning depend on their spatial structure. The spatial structure is conventionally classified as either regular, when the patches of biomass are of similar size and are spaced in similar intervals, or irregular. The formation of regular patterns is driven by scale-dependent feedbacks. Models incorporating those feedbacks generate highly regular patterns, while natural patterns appear less regular. This calls for a more nuanced quantification beyond a binary classification. Here, we propose measuring the degree of regularity by the maximum of a pattern’s spectral density, based on the observation that the density of highly regular patterns consists of a narrow and high peak, while the density of highly irregular patterns consists of a low and wide lobe. We rescale the density to make the measure invariant with respect to the characteristic length-scale of a pattern, facilitating the comparison of patterns observed or modelled under different conditions. We demonstrate our method in a metastudy determining the regularity of natural and model-generated patterns depicted in previous studies. We find that natural patterns have an intermediate degree of regularity, resembling random surfaces generated by stochastic processes. We find that conventional deterministic models do not reproduce the intermediate regularity of natural patterns, as they generate patterns which are much more regular and similar to periodic surfaces. We call for appreciating the stochasticity of natural patterns in systems with scale-dependent feedbacks.</div></div>","PeriodicalId":50559,"journal":{"name":"Ecological Complexity","volume":"60 ","pages":"Article 101104"},"PeriodicalIF":3.1,"publicationDate":"2024-10-30","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142553460","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"环境科学与生态学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2024-10-16DOI: 10.1016/j.ecocom.2024.101105
Carlos Pinilla Cruz , Pedro Luna , Fabricio Villalobos , Roger Guevara , Ismael Hinojoza-Díaz , Wesley Dáttilo
The honeybee Apis mellifera is an introduced managed pollinator species in many world regions and exhibits a high capacity to compete for resources against native bee species. Despite empirical evidence showing that A. mellifera establishes a great number of interactions within plant-bee interaction networks (i.e., high interactive role), little is known on whether its interactive role changes along elevational gradients. Being motivated by these concerns, here we assessed the species richness of plants, bees, interaction diversity, and the interactive role of A. mellifera within plant-bee interaction networks along an elevation gradient from the coastal dunes (4 m.a.s.l.) of the Gulf of Mexico up to the pine-fir forests (3425 m.a.s.l.) in the extinct volcano Cofre de Perote in Mexico. Moreover, we evaluated the interactive role of A. mellifera’s on the diversity of plant-bee interactions along this elevational gradient. We found a decrease in the richness of plants, bees, interaction diversity as elevation increased, and the interactive role of A. mellifera within the networks also decreased with elevation. Moreover, the interactive role of A. mellifera had no effect on the diversity of plant-bee interactions along the studied elevational gradient. These findings indicate that climatic conditions could be filtering plant and bee species and their interactions, even the interactions of a super generalist species as A. mellifera. In short, our study helps understand the responses of species and their biotic interactions over Neotropical elevational gradients. By examining the pronounced climatic shifts, similar to those induced by climate change, we also highlight the sensitivity of these responses to significant environmental alterations. Our findings underscore the critical importance of understanding ecological dynamics in the face of rapidly changing climates.
蜜蜂(Apis mellifera)是世界上许多地区引进的人工授粉物种,与本地蜜蜂物种竞争资源的能力很强。尽管经验证据表明,蜜蜂在植物-蜜蜂互动网络中建立了大量互动关系(即高互动作用),但人们对蜜蜂的互动作用是否会随着海拔梯度的变化而变化知之甚少。出于这些考虑,我们在此评估了从墨西哥湾沿海沙丘(海拔 4 米)到墨西哥 Cofre de Perote 死火山松杉林(海拔 3425 米)的海拔梯度上植物、蜜蜂的物种丰富度、交互多样性以及 A. mellifera 在植物-蜜蜂交互网络中的交互作用。此外,我们还评估了 A. mellifera 在这一海拔梯度上对植物-蜜蜂相互作用多样性的交互作用。我们发现,随着海拔的升高,植物、蜜蜂和互动多样性的丰富程度有所降低,而 A. mellifera 在网络中的互动作用也随着海拔的升高而降低。此外,在所研究的海拔梯度上,A. mellifera的交互作用对植物-蜜蜂交互作用的多样性没有影响。这些发现表明,气候条件可能会过滤植物和蜜蜂物种及其相互作用,甚至是像A. mellifera这样的超级通才物种的相互作用。简而言之,我们的研究有助于了解物种及其生物相互作用在新热带海拔梯度上的反应。通过研究明显的气候转变(类似于气候变化引起的转变),我们还强调了这些反应对重大环境变化的敏感性。我们的研究结果突出表明,面对快速变化的气候,了解生态动态至关重要。
{"title":"The central importance of the honeybee (Apis mellifera L.) within plant-bee interaction networks decreases along a Neotropical elevational gradient","authors":"Carlos Pinilla Cruz , Pedro Luna , Fabricio Villalobos , Roger Guevara , Ismael Hinojoza-Díaz , Wesley Dáttilo","doi":"10.1016/j.ecocom.2024.101105","DOIUrl":"10.1016/j.ecocom.2024.101105","url":null,"abstract":"<div><div>The honeybee <em>Apis mellifera</em> is an introduced managed pollinator species in many world regions and exhibits a high capacity to compete for resources against native bee species. Despite empirical evidence showing that <em>A. mellifera</em> establishes a great number of interactions within plant-bee interaction networks (i.e., high interactive role), little is known on whether its interactive role changes along elevational gradients. Being motivated by these concerns, here we assessed the species richness of plants, bees, interaction diversity, and the interactive role of <em>A. mellifera</em> within plant-bee interaction networks along an elevation gradient from the coastal dunes (4 m.a.s.l.) of the Gulf of Mexico up to the pine-fir forests (3425 m.a.s.l.) in the extinct volcano Cofre de Perote in Mexico. Moreover, we evaluated the interactive role of <em>A. mellifera</em>’s on the diversity of plant-bee interactions along this elevational gradient. We found a decrease in the richness of plants, bees, interaction diversity as elevation increased, and the interactive role of <em>A. mellifera</em> within the networks also decreased with elevation. Moreover, the interactive role of <em>A. mellifera</em> had no effect on the diversity of plant-bee interactions along the studied elevational gradient. These findings indicate that climatic conditions could be filtering plant and bee species and their interactions, even the interactions of a super generalist species as <em>A. mellifera</em>. In short, our study helps understand the responses of species and their biotic interactions over Neotropical elevational gradients. By examining the pronounced climatic shifts, similar to those induced by climate change, we also highlight the sensitivity of these responses to significant environmental alterations. Our findings underscore the critical importance of understanding ecological dynamics in the face of rapidly changing climates.</div></div>","PeriodicalId":50559,"journal":{"name":"Ecological Complexity","volume":"60 ","pages":"Article 101105"},"PeriodicalIF":3.1,"publicationDate":"2024-10-16","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142442723","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"环境科学与生态学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2024-10-16DOI: 10.1016/j.ecocom.2024.101106
Marc Djahangard , Han Zhang , Rasoul Yousefpour
Climate change affects Central European forest ecosystems in different ways and, consequently, these changes result in different feedbacks on the provision of forest ecosystem services. Regarding the complexity and the variability in climate-forest interactions outcome, forest decision makers necessitate reliable information about changes in the forest ecosystem services for planning and adaptation purposes. However, forest productivity predictions incorporate multiple levels of uncertainty that have to be regarded to ensure building realistic expectations in forest decision-making. Besides the chosen forest simulation model, uncertainties come from the climate change data represented by a set of representative concentration pathways (RCP), within the underlying ensemble of global circulation and regional climate models (GCM-RCM), and further in the treatment of the CO2-fertilization effect. We considered the mentioned uncertainties in a framework on simulating forest growth and water services for two forest sites, a Sessile oak and a Scots pine stand in Rhineland-Palatine, Germany. The framework revealed a high variability in future forest ecosystem services. Particularly, the variability among the selected GCM-RCM models within the same Representative Concentration Pathway (RCP) was higher than the variability among different RCPs (RCP2.6 and RCP8.5 representing the low and high CO2-emission scenarios, respectively). Sessile oak productivity increased under all scenarios, whereas Scots pine growth declined in the lower end of the RCP8.5 scenario. Water services remained mostly stable at both sites. Moreover, we applied a panel data model to estimate what climate indices caused changes in the forest ecosystem services. We found that Scots pine is more sensitive to a multitude of climate indices, such as temperature changes and Sessile oak showed strong response to the CO2-fertilization. We propose applying this framework to evaluate forest management options under climate change.
{"title":"Assessing the ecological complexity and uncertainty of predicting forest ecosystem services under climate change","authors":"Marc Djahangard , Han Zhang , Rasoul Yousefpour","doi":"10.1016/j.ecocom.2024.101106","DOIUrl":"10.1016/j.ecocom.2024.101106","url":null,"abstract":"<div><div>Climate change affects Central European forest ecosystems in different ways and, consequently, these changes result in different feedbacks on the provision of forest ecosystem services. Regarding the complexity and the variability in climate-forest interactions outcome, forest decision makers necessitate reliable information about changes in the forest ecosystem services for planning and adaptation purposes. However, forest productivity predictions incorporate multiple levels of uncertainty that have to be regarded to ensure building realistic expectations in forest decision-making. Besides the chosen forest simulation model, uncertainties come from the climate change data represented by a set of representative concentration pathways (RCP), within the underlying ensemble of global circulation and regional climate models (GCM-RCM), and further in the treatment of the CO<sub>2</sub>-fertilization effect. We considered the mentioned uncertainties in a framework on simulating forest growth and water services for two forest sites, a Sessile oak and a Scots pine stand in Rhineland-Palatine, Germany. The framework revealed a high variability in future forest ecosystem services. Particularly, the variability among the selected GCM-RCM models within the same Representative Concentration Pathway (RCP) was higher than the variability among different RCPs (RCP2.6 and RCP8.5 representing the low and high CO<sub>2</sub>-emission scenarios, respectively). Sessile oak productivity increased under all scenarios, whereas Scots pine growth declined in the lower end of the RCP8.5 scenario. Water services remained mostly stable at both sites. Moreover, we applied a panel data model to estimate what climate indices caused changes in the forest ecosystem services. We found that Scots pine is more sensitive to a multitude of climate indices, such as temperature changes and Sessile oak showed strong response to the CO<sub>2</sub>-fertilization. We propose applying this framework to evaluate forest management options under climate change.</div></div>","PeriodicalId":50559,"journal":{"name":"Ecological Complexity","volume":"60 ","pages":"Article 101106"},"PeriodicalIF":3.1,"publicationDate":"2024-10-16","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142442587","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"环境科学与生态学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2024-10-16DOI: 10.1016/j.ecocom.2024.101102
Jakub Z. Kosicki
Describing mechanisms that ensure stable co-occurrence of sympatric species is fundamental to understanding the complexity of ecological community dynamics. In this study, the Pied flycatcher and the Collared flycatcher were used as model species for the analysis of co-occurrence patterns of closely related hybridising species that inhabit overlapping forest habitats. I hypothesise that spatial niche partitioning between species emerges as a vital adaptive response to interspecific competition and manifests itself in significant shifts in habitat preferences in syntopic areas but not in the allotopic ones. The study leverages a comprehensive dataset that includes species density in 372 randomly selected 1 km² grid cells across the territory of Poland. The analysis of habitat preferences was performed with linear mixed-effect modeling, whereas a contrast analysis was used to investigate changes in habitat preferences resulting from the presence of a competitor. The findings indicate that both species modify their habitat preferences when transitioning between syntopic and allotopic sites. Remarkably, in regions without competitors, such shifts are significantly less pronounced, as demonstrated by the Pied flycatcher that prefers the same habitats both in allopatric regions and allotopic sites. When these results are compared with other studies on closely related hybridising and non-hybridising species, it turns out that what influences the degree and number of niches subjected to competition is the time that passes from species divergence. This study highlights the imperative need to incorporate co-occurrence parameters of closely related species into niche and species distribution models to enhance their ecological realism.
{"title":"Niche divergence mechanisms of closely related hybridising bird species. Modeling approach based on remote sensing data of forest habitats","authors":"Jakub Z. Kosicki","doi":"10.1016/j.ecocom.2024.101102","DOIUrl":"10.1016/j.ecocom.2024.101102","url":null,"abstract":"<div><div>Describing mechanisms that ensure stable co-occurrence of sympatric species is fundamental to understanding the complexity of ecological community dynamics. In this study, the Pied flycatcher and the Collared flycatcher were used as model species for the analysis of co-occurrence patterns of closely related hybridising species that inhabit overlapping forest habitats. I hypothesise that spatial niche partitioning between species emerges as a vital adaptive response to interspecific competition and manifests itself in significant shifts in habitat preferences in syntopic areas but not in the allotopic ones. The study leverages a comprehensive dataset that includes species density in 372 randomly selected 1 km² grid cells across the territory of Poland. The analysis of habitat preferences was performed with linear mixed-effect modeling, whereas a contrast analysis was used to investigate changes in habitat preferences resulting from the presence of a competitor. The findings indicate that both species modify their habitat preferences when transitioning between syntopic and allotopic sites. Remarkably, in regions without competitors, such shifts are significantly less pronounced, as demonstrated by the Pied flycatcher that prefers the same habitats both in allopatric regions and allotopic sites. When these results are compared with other studies on closely related hybridising and non-hybridising species, it turns out that what influences the degree and number of niches subjected to competition is the time that passes from species divergence. This study highlights the imperative need to incorporate co-occurrence parameters of closely related species into niche and species distribution models to enhance their ecological realism.</div></div>","PeriodicalId":50559,"journal":{"name":"Ecological Complexity","volume":"60 ","pages":"Article 101102"},"PeriodicalIF":3.1,"publicationDate":"2024-10-16","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142442749","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"环境科学与生态学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2024-10-16DOI: 10.1016/j.ecocom.2024.101103
John Vandermeer
Based on the classical idea that no two species can occupy the same niche, ecological communities are frequently assumed to be structured according to the rules of interspecific competition, based on the intuition provided by the Lotka/Volterra competition equations in two dimensions. It has been noted that when three or more species are involved, the usual tacit assumption that all competition is transitive may be violated. Intransitive loops change some of the emergent principles of the competition-based framework of community structure. Since the intransitivity is oscillatory, the convenient stable equilibrium approach to communities is altered and oscillatory behavior of the system needs to be acknowledged. It is likely that real communities, especially if they are relatively large, will contain one or more intransitive structures, along with normal transitivities. Here we examine some theoretical constructs that emanate from the joint consideration of intransitive and transitive structures co-occurring in an ecological community.
{"title":"Transitive and intransitive structures in competition-based ecological communities","authors":"John Vandermeer","doi":"10.1016/j.ecocom.2024.101103","DOIUrl":"10.1016/j.ecocom.2024.101103","url":null,"abstract":"<div><div>Based on the classical idea that no two species can occupy the same niche, ecological communities are frequently assumed to be structured according to the rules of interspecific competition, based on the intuition provided by the Lotka/Volterra competition equations in two dimensions. It has been noted that when three or more species are involved, the usual tacit assumption that all competition is transitive may be violated. Intransitive loops change some of the emergent principles of the competition-based framework of community structure. Since the intransitivity is oscillatory, the convenient stable equilibrium approach to communities is altered and oscillatory behavior of the system needs to be acknowledged. It is likely that real communities, especially if they are relatively large, will contain one or more intransitive structures, along with normal transitivities. Here we examine some theoretical constructs that emanate from the joint consideration of intransitive and transitive structures co-occurring in an ecological community.</div></div>","PeriodicalId":50559,"journal":{"name":"Ecological Complexity","volume":"60 ","pages":"Article 101103"},"PeriodicalIF":3.1,"publicationDate":"2024-10-16","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142442588","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"环境科学与生态学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2024-10-10DOI: 10.1016/j.ecocom.2024.101101
Martin Drechsler
Conservation offsets are increasingly used as an instrument for biodiversity conservation on private lands. Since the restoration of degraded land often involves uncertainties and time lags, conservation biologists have recommended that credits in conservation offset schemes be awarded only with the completion of the restoration process (“savings bank”). These arguments, however, ignore that such a scheme design may incur higher economic costs than a design in which credits are already awarded at the initiation of the restoration process (“lending bank”). Here a generic agent-based ecological-economic simulation model is developed to explore the cost-effectiveness of savings and lending banks. The economic model compartment considers spatially heterogeneous and dynamic conservation costs and time preferences in the landowners. The ecological compartment considers uncertainty in the duration and the success of restoration process, and in the metapopulation dynamics of a species described by the rates of local population extinction and the colonisation of empty habitat patches. By this the widely used offset metric of “habitat hectares” is replaced by “metapopulation viability” which is commonly used in conservation biology. It turns out that whether credits should be awarded at the initiation or with completion of restoration depends on the ecological and economic circumstances. Larger colonisation and extinction rates, e.g., tend to favour the awarding of credits with the initiation of habitat restoration.
{"title":"Should the biodiversity bank be a savings bank or a lending bank?","authors":"Martin Drechsler","doi":"10.1016/j.ecocom.2024.101101","DOIUrl":"10.1016/j.ecocom.2024.101101","url":null,"abstract":"<div><div>Conservation offsets are increasingly used as an instrument for biodiversity conservation on private lands. Since the restoration of degraded land often involves uncertainties and time lags, conservation biologists have recommended that credits in conservation offset schemes be awarded only with the completion of the restoration process (“savings bank”). These arguments, however, ignore that such a scheme design may incur higher economic costs than a design in which credits are already awarded at the initiation of the restoration process (“lending bank”). Here a generic agent-based ecological-economic simulation model is developed to explore the cost-effectiveness of savings and lending banks. The economic model compartment considers spatially heterogeneous and dynamic conservation costs and time preferences in the landowners. The ecological compartment considers uncertainty in the duration and the success of restoration process, and in the metapopulation dynamics of a species described by the rates of local population extinction and the colonisation of empty habitat patches. By this the widely used offset metric of “habitat hectares” is replaced by “metapopulation viability” which is commonly used in conservation biology. It turns out that whether credits should be awarded at the initiation or with completion of restoration depends on the ecological and economic circumstances. Larger colonisation and extinction rates, e.g., tend to favour the awarding of credits with the initiation of habitat restoration.</div></div>","PeriodicalId":50559,"journal":{"name":"Ecological Complexity","volume":"60 ","pages":"Article 101101"},"PeriodicalIF":3.1,"publicationDate":"2024-10-10","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142423021","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"环境科学与生态学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}