Impacts of large herbivores on terrestrial ecosystems

Current Biology, Journal Year: 2023, Volume and Issue: 33(11), P. R584 - R610

Published: June 1, 2023

Language: Английский

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Context dependency of animal resource subsidies

Biological reviews/Biological reviews of the Cambridge Philosophical Society, Journal Year: 2018, Volume and Issue: 94(2), P. 517 - 538

Published: Sept. 24, 2018

The transport of resource subsidies by animals has been documented across a range species and ecosystems. Although many these studies have shown that animal can significant effects on nutrient cycling, ecosystem productivity, food-web structure, there is great deal variability in the occurrence strength effects. Here we propose conceptual framework for understanding context dependency subsidies, developing testing predictions about over space time. We general framework, which abiotic characteristics vector from donor interact to determine quantity, quality, timing, duration (QQTD) an input. input translated through lens recipient characteristics, include both consumer yield QQTD subsidy. subsidy influences dynamics trophic structure function, may influence ecosystem's response further inputs feed back ecosystem. present review research boundaries, placed within this discuss how function explore importance increasingly altered ecosystems, vectors ecosystems be changing rapidly. Finally, make recommendations future general, will increase our predictive capacity their

Language: Английский

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Gas exchange in streams and rivers

Wiley Interdisciplinary Reviews Water, Journal Year: 2019, Volume and Issue: 7(1)

Published: Oct. 23, 2019

Abstract Gas exchange across the air–water boundary of streams and rivers is a globally large biogeochemical flux. depends on solubility gas interest, concentrations air water, velocity ( k ), usually normalized to Schmidt number 600, referred as 600 . intense research interest because it problematic estimate, highly spatially variable, has high prediction error. Theory dictates that molecular diffusivity turbulence drives variation in flowing waters. We measure via several methods from direct measures, tracer experiments, modeling diel changes dissolved concentrations. Many estimates show surface explains leading predictive models based upon geomorphic hydraulic variables. These variables include stream channel slope flow velocity, product which, proportional energy dissipation rate rivers. empirical provide understanding controls , yet residual these simple are insufficient for predicting individual locations. The most appropriate method estimate scientific question along with characteristics study sites. decision tree selecting best river reaches scaling networks. This article categorized under: Water Life > Nature Freshwater Ecosystems Science Quality Methods

Language: Английский

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Uncovering the complete biodiversity structure in spatial networks: the example of riverine systems

Oikos, Journal Year: 2020, Volume and Issue: 129(5), P. 607 - 618

Published: Jan. 13, 2020

Uncovering biodiversity as an inherent feature of ecosystems and understanding its effects on ecosystem processes is one the most central goals ecology. Studying organisms’ occurrence patterns in natural has spurred discovery foundational ecological rules, such species–area relationship, general scientific interest. Recent global changes add relevance urgency to diversity organisms, their respective roles processes. While information properties abiotic environmental conditions are now available at unprecedented, highly‐resolved spatial temporal scales, fundamental variable – itself still often studied a local perspective, generally not wide taxonomic breadth, high scale coverage. This limiting capacity impact ecology field science. In this forum article, we propose that complete assessments should be inclusive across functional groups, space, time better understand emergent properties, functioning. We use riverine case example because they among biodiverse worldwide, but also highly threatened, in‐depth these systems critically needed. Furthermore, structure requires multiscale perspective consideration autocorrelation structures commonly ignored biodiversity–ecosystem functioning studies. show how recent methodological advances DNA (eDNA) provide novel opportunities uncover broad link it processes, with potential revolutionize sciences. then outline roadmap for using technique assess manner. Our proposed approach will help get associated scales relevant landscape managers.

Language: Английский

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Towards (better) fluvial meta-ecosystem ecology: a research perspective

npj Biodiversity, Journal Year: 2024, Volume and Issue: 3(1)

Published: Feb. 7, 2024

Rivers are an important component of the global carbon cycle and contribute to atmospheric exchange disproportionately their total surface area. Largely, this is because rivers efficiently mobilize, transport metabolize terrigenous organic matter (OM). Notably, our knowledge about magnitude globally relevant fluxes strongly contrasts with lack understanding underlying processes that transform OM. Ultimately, OM processing en route oceans results from a diverse assemblage consumers interacting equally pool resources in spatially complex network heterogeneous riverine habitats. To understand interaction between OM, we must therefore account for spatial configuration, connectivity, landscape context at scales ranging local ecosystems entire networks. Building such explicit framework fluvial across may also help us better predict poorly understood anthropogenic impacts on cycling, instance human-induced fragmentation changes flow regimes, including intermittence. Moreover, current unprecedented human-driven loss biodiversity. This least partly due mechanisms operating scales, as interference migration habitat homogenization, comes largely unknown functional consequences. We advocate here comprehensive networks connecting two aware but disparate lines research (i) metacommunities biodiversity, (ii) biogeochemistry contribution cycle. argue agenda focusing regional scale-that is, river network-to enable deeper mechanistic naturally arising biodiversity-ecosystem functioning coupling major driver biogeochemically fluxes.

Language: Английский

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Megaherbivore impacts on ecosystem and Earth system functioning: the current state of the science

Ecography, Journal Year: 2021, Volume and Issue: 44(11), P. 1579 - 1594

Published: Sept. 22, 2021

Megaherbivores (adult body mass > 1000 kg) are suggested to disproportionately shape ecosystem and Earth system functioning. We systematically reviewed the empirical basis for this general thesis more specific hypotheses that 1) megaherbivores have larger effects on functioning than their smaller counterparts, 2) is true all extant megaherbivore species 3) vary along environmental gradients. furthermore explored possible biases in our understanding of impacts. found there too few studies quantitatively evaluate or any but African savanna elephant. Following finding, we performed a qualitative vote counting analysis. Our synthesis analysis suggests can elicit strong impacts on, example, vegetation structure biodiversity, elephant promote seed dispersal. were, however, unable whether these disproportionate large herbivores. Although conditions mediate impact, quantified effect rainfall soil fertility impacts, precluding prediction system, particularly under future climates. Moreover, review highlights major taxonomic, thematic geographic effects. Most focused with other functions comparatively neglected. Studies were also biased towards semi‐arid relatively fertile systems, arid, high‐rainfall and/or nutrient‐poor parts megaherbivores' distribution ranges largely unrepresented. findings highlight ecological still limited species, except elephant, current certain areas. further outline detailed, urgently needed avenue research.

Language: Английский

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Are hippos Africa's most influential megaherbivore? A review of ecosystem engineering by the semi‐aquatic common hippopotamus

Biological reviews/Biological reviews of the Cambridge Philosophical Society, Journal Year: 2023, Volume and Issue: 98(5), P. 1509 - 1529

Published: April 24, 2023

Megaherbivores perform vital ecosystem engineering roles, and have their last remaining stronghold in Africa. Of Africa's megaherbivores, the common hippopotamus (Hippopotamus amphibius) has received least scientific conservation attention, despite how influential activities appear to be. Given potentially crucial influence of hippos, as well mounting concerns threatening long-term persistence, a review evidence for hippos being engineers, effects engineering, is both timely necessary. In this review, we assess, (i) aspects hippo biology that underlie unique potential; (ii) evaluate ecological impacts terrestrial aquatic environments; (iii) compare other extant African megaherbivores; (iv) factors most critical engineering; (v) highlight future research directions challenges may yield new insights into role megaherbivores more broadly. We find variety key life-history traits determine hippo's influence, including semi-aquatic lifestyle, large body size, specialised gut anatomy, muzzle structure, small partially webbed feet, highly gregarious nature. On land, create grazing lawns contain distinct plant communities alter fire spatial extent, which shapes woody demographics might assist maintaining fire-sensitive riverine vegetation. water, deposit nutrient-rich dung, stimulating food chains altering water chemistry quality, impacting host different organisms. Hippo trampling wallowing alters geomorphological processes, widening riverbanks, creating river channels, forming gullies along well-utilised paths. Taken together, propose these myriad combine make megaherbivore, specifically because high diversity intensity compared with capacity transfer nutrients across boundaries, enriching ecosystems. Nonetheless, pollution extraction agriculture industry, erratic rainfall patterns human-hippo conflict, threaten persistence. Therefore, encourage greater consideration engineers when considering functional importance megafauna ecosystems, increased attention declining habitat populations, if unchecked could change way many ecosystems function.

Language: Английский

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Composition of cetacean communities worldwide shapes their contribution to ocean nutrient cycling

Nature Communications, Journal Year: 2023, Volume and Issue: 14(1)

Published: Sept. 19, 2023

Defecation by large whales is known to fertilise oceans with nutrients, stimulating phytoplankton and ecosystem productivity. However, our current understanding of these processes limited a few species, nutrients ecosystems. Here, we investigate the role cetacean communities in worldwide biological cycling two major six trace nutrients. We show that cetaceans release more mesotrophic eutrophic temperate waters than oligotrophic tropical waters, mirroring patterns The released nutrient cocktails also vary geographically, driven composition communities. roles small cetaceans, deep diving baleen differ quantitatively functionally, contributions divers exceeding those some areas. functional diversity expands beyond their as top predators include active vectors, which might be equally important local dynamics.

Language: Английский

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Rewiring the Carbon Cycle: A Theoretical Framework for Animal‐Driven Ecosystem Carbon Sequestration

Journal of Geophysical Research Biogeosciences, Journal Year: 2024, Volume and Issue: 129(4)

Published: March 31, 2024

Abstract Most carbon cycle models do not consider animal‐mediated effects, focusing instead on exchanges among plants, microbes, and the atmosphere. Yet, a growing body of empirical evidence from diverse ecosystems points to pervasive animal effects ecosystem cycling shows that ignoring them could lead misrepresentation an ecosystem's cycle. We develop new theoretical framework account for cycling. combine classic compartment modeling approach with model flux storage plant, animal, soil microbial trophic compartments. show, by way numerical analyses steady state conditions across three competing scenarios, presence alters dominant pathways control over capture. This altered arises via direct, consumptive especially indirect, non‐consumptive instigating faster nutrient recycling. leads quantitative change in balance, enhancing amount captured stored ecosystem. Further, indirect appear important enabling these because their sensitivity structure food chain. The animals play larger role than previously thought. Our provides further guidance research aimed at quantifying inform development nature‐based climate solutions leverage influence help mitigate change.

Language: Английский

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Monitoring the dead as an ecosystem indicator

Ecology and Evolution, Journal Year: 2021, Volume and Issue: 11(11), P. 5844 - 5856

Published: May 1, 2021

Abstract Dead animal biomass (carrion) is present in all terrestrial ecosystems, and its consumption, decomposition, dispersal can have measurable effects on vertebrates, invertebrates, microbes, parasites, plants, soil. But despite the number of studies examining influence carrion food webs, there has been no attempt to identify how general ecological processes around might be used as an ecosystem indicator. We suggest that knowledge scavenging decomposition rates, scavenger diversity, abundance, behavior carrion, along with assessments vegetation, soil, microbe, parasite presence, individually or combination understand web dynamics. Monitoring could also assist comparisons among landscapes biomes. Although outstanding research needed fully integrate ecology monitoring into management, we see great potential using indicator intact functional web.

Language: Английский

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