Biodiversity dynamics in the Anthropocene: how human activities change equilibria of species richness

Ecography, Год журнала: 2021, Номер 2022(4)

Опубликована: Авг. 29, 2021

We are living in a time of rapid environmental changes caused by anthropogenic pressures. Besides direct human exploitation plant and animal populations habitat transformation, biodiversity the Anthropocene affected less trivial processes including spreading non‐native species, emergence novel communities modifications ecosystem functioning due to changing nutrient cycles climate changes. These so complex that confident predictions effective conservation cannot be obtained without suitable theory dynamics. argue such dynamics have particular attractors, i.e. stable equilibria, determined conditions. equilibria set limits, carrying capacities for biodiversity, from local global scales. point out evidence limits at various spatiotemporal scales show, using new equilibrium (ETBD), how diversity depend on non‐linear relationships between number community abundance population size‐dependent species extinction origination (speciation or colonization). show effects can lead multiple tipping points. Various activities, introductions, appropriation primary production trophic downgrading, change local, regional affecting levels. The existence out‐of‐equilibrium states has important implications conservation, restoration reconciliation ecology. It highlights need more effectively intentionally balance historical focus preservation natural habitats with management specifically directed towards responsible long‐term maintenance equilibria. represents unique situation which people make decisions concerning world, we ecological requires wisely deciding alternative worth maintaining.

Язык: Английский

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Exploring a natural baseline for large‐herbivore biomass in ecological restoration

Journal of Applied Ecology, Год журнала: 2021, Номер 59(1), С. 18 - 24

Опубликована: Ноя. 2, 2021

Abstract Large herbivores provide key ecosystem processes, but have experienced massive historical losses and are under intense pressure, leaving current ecosystems with dramatically simplified faunas relative to the long‐term evolutionary norm. Hampered by a shifting baseline, natural levels of large‐herbivore biomass poorly understood seldom targeted. This ‘Decade restoration’ calls for evidence‐based targets restoring diversity large herbivores. We apply scaling consumer–producer relationship global dataset density in areas. The analyses reveal that African generally much higher also strongest relationship. For Europe, Asia South America, there no significant relationships primary productivity indicative impoverished faunas. Compared expectations from relation, outside Africa is considerably lower than expected. Synthesis applications . Ecological restoration rewilding entail grazing process. Our findings indicate many nature reserves depleted biomass, judged their productivity. Meanwhile, overexploitation seasonal livestock takes place other It thus difficult, urgent, reach scientific consensus regarding baseline biomass. Until such agreement has been reached, we recommend manage, or rewild, year‐round near‐natural without predefined targets, following fluctuating resource availability minimal management intervention. establishment experimental sites reactive herbivore needed further advance our understanding density.

Язык: Английский

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Population density estimates for terrestrial mammal species

Global Ecology and Biogeography, Год журнала: 2022, Номер 31(5), С. 978 - 994

Опубликована: Март 8, 2022

Abstract Aim Population density is a key parameter in ecology and conservation, estimates of population are required for wide variety applications fundamental applied ecology. Yet, terrestrial mammals these data available only minority species, their availability taxonomically geographically biased. Here, we provide the most plausible predictions average density, natural variability statistical uncertainty 4,925 mammal species. Location Global. Time period 1970–2021. Major taxa studied Terrestrial mammals. Methods We fitted an additive mixed‐effect model accounting spatial phylogenetic autocorrelation on dataset including 5,412 737 Average was modelled as function body mass, diet, locomotor habits environmental conditions. validated using taxonomic block cross‐validation used estimated error to quantify around Results Small size, fossorial behaviour herbivorous diets were associated with highest densities, whereas large aerial carnivorous related lowest densities. Species non‐seasonal environments yielded higher densities than species high precipitation seasonality. Empirical vary by about four times within same statistically independent majority deviate five from observed values, indicating that prediction errors similar Main conclusions Our open up number macroecology conservation biogeography, biomass estimation, setting targets assessments planning, supporting Red List assessments. The methodology can be replicated easily other groups representative sample georeferenced estimates.

Язык: Английский

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Plankton energy flows using a global size-structured and trait-based model

Progress In Oceanography, Год журнала: 2022, Номер 209, С. 102898 - 102898

Опубликована: Сен. 21, 2022

Plankton community models are critical tools for understanding the processes that shape marine plankton communities, how communities impact biogeochemical cycles, and feedbacks between structure function. Here, using flexible Marine Biogeochemistry Library (MARBL), we present Size-based ECological TRAits (MARBL-SPECTRA) model, which is designed to represent a diverse while remaining computationally tractable. MARBL-SPECTRA composed of nine phytoplankton six zooplankton size classes represented allometric scaling relationships physiological traits interactions within multiple functional types. embedded global ocean component Community Earth System Model (CESM) simulates large-scale, emergent patterns in growth limitation, phenology, generation time, trophic transfer efficiency. The model qualitatively reproduces observed surface nutrients, chlorophyll biomass, net primary production, biogeographies range classes. In addition, predator:prey dynamics efficiency vary across gradients total ecosystem productivity. Shorter food chains export proportionally more carbon from interior occur productive, eutrophic regions, whereas oligotrophic relatively long less organic matter surface. union type modeling with size-resolved, trait-based approaches allows capture both large-scale elemental cycles planktonic webs affecting

Язык: Английский

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Eco-evolutionary emergence of macroecological scaling in plankton communities

Science, Год журнала: 2024, Номер 383(6684), С. 777 - 782

Опубликована: Фев. 15, 2024

Macroecological scaling patterns, such as between prey and predator biomass, are fundamental to our understanding of the rules biological organization ecosystem functioning. Although these patterns ubiquitous, how they arise is poorly understood. To explain we used an eco-evolutionary predator-prey model parameterized using data for phytoplankton zooplankton. We show that allometric relationships at lower levels organization, body-size nutrient uptake predation, give rise food web levels. Our predicted macroecological exponents agree well with observed values across ecosystems. findings explicitly connect different ecological evolutionary mechanisms, yielding testable hypotheses emerge.

Язык: Английский

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