The distribution of biodiversity richness in the tropics

Science Advances, Journal Year: 2020, Volume and Issue: 6(37)

Published: Sept. 9, 2020

Latin America has more than twice as many vascular plant species Africa south of the Sahara plus Madagascar, in a smaller area.

Language: Английский

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The Greening of the Sahara: Past Changes and Future Implications

One Earth, Journal Year: 2020, Volume and Issue: 2(3), P. 235 - 250

Published: March 1, 2020

In the future, Sahara and Sahelian regions could experience more rainfall than today as a result of climate change. Wetter periods, termed African humid occurred in past witnessed mesic landscape place today's hyperarid semiarid environment. Such large changes raise question whether near future might hold store similar environmental transformations, particularly view growing human-induced climate, land-use, land-cover changes. last decades, geoengineering initiatives (in form active re-greening projects Sahel) have been proposed significant effects on region. Here, we synthesize literature projected hydroclimate Sahelian-Saharan region associated feedbacks. We further address current state knowledge concerning Saharan afforestation their consequences. Our review underscores importance vegetation land-atmosphere-ocean feedback processes far-field impacts northern ecosystem

Language: Английский

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Biome: evolution of a crucial ecological and biogeographical concept

New Phytologist, Journal Year: 2018, Volume and Issue: 222(1), P. 97 - 114

Published: Nov. 27, 2018

Summary A biome is a key community ecological and biogeographical concept and, as such, has profited from the overall progress of ecology, punctuated by two major innovations: shifting focus pure pattern description to understanding functionality, changing approach observational explanatory most importantly, descriptive predictive. The functional enabled development mechanistic function‐focused predictive retrodictive modelling; it also shaped current dynamic biological entity having many aspects, with deep roots in evolutionary past, which undergoing change. evolution was three synthetic steps: first synthesis formulated solid body theory explaining meaning zonality collated our knowledge on drivers vegetation patterns at large spatial scales; second translated this into effective modelling tools, developing further link between ecosystem functionality biogeography; third (still progress) seeking common ground large‐scale biogeographic phenomena, using macroecology macroevolutionary research tools.

Language: Английский

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Woody plant encroachment intensifies under climate change across tundra and savanna biomes

Global Ecology and Biogeography, Journal Year: 2020, Volume and Issue: 29(5), P. 925 - 943

Published: Feb. 19, 2020

Abstract Aim Biomes worldwide are shifting with global change. whose extents limited by temperature or precipitation, such as the tundra and savanna, may be particularly strongly affected climate While woody plant encroachment is prevalent across both biomes, its relationship to precipitation change remains unknown. Here, we quantify degree which related identify main associated drivers. Location Tundra savanna biomes. Time period 1992 ± 20.27–2010 5.62 (mean SD ). 1876–2016 (range). Major taxa studied Woody plants (shrubs trees). Methods We compiled a dataset comprising 1,089 records from 899 sites of cover over time attributed drivers these two calculated in each biome assessed corresponds concurrent changes using multiple metrics. Finally, conducted quantitative literature review relative importance Results was widespread geographically gradients. Rates (positive negative) were 1.8 times lower than (1.8 vs. 3.2%), while rates increase (i.e., encroachment) c. 1.7 compared (3.7 6.3% per decade). In tundra, magnitudes did not correspond climate, greater corresponded increases precipitation. found higher wetter versus drier warming biome, increasing savanna. However, faster more rapid sites, except for maximum Main conclusions positively increased rainfall predicted change, can partially explained interactions Additional likely influences include site‐level factors, time‐lags, plant‐specific responses, land use other non‐climate Our findings highlight complex nature impacts biomes seasonality, should accounted realistically estimate future responses open under scenarios.

Language: Английский

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A unified framework for plant life‐history strategies shaped by fire and herbivory

New Phytologist, Journal Year: 2019, Volume and Issue: 224(4), P. 1490 - 1503

Published: June 9, 2019

Fire and herbivory both remove aboveground biomass. Environmental factors determine the type intensity of these consumers globally, but traits plants can also alter their propensity to burn degree which they are eaten. To understand plant life-history strategies associated with fire we need describe response effect functional traits, how sort within communities, along resource gradients, across evolutionary timescales. herbivore generally considered separately, there advances made in understanding that relate herbivory, vice versa. Moreover, interact: presence one consumer affects other. Here, present a unifying conceptual framework enable tolerance persistence herbivory. Using grasses as an example, discuss flammability tolerance, palatability, grazing might organize themselves ecosystems exposed consumers, have evolved reference other strong selective processes, like aridity. Our be used predict diversity species under different regimes.

Language: Английский

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The last continuous grasslands on Earth: Identification and conservation importance

Conservation Science and Practice, Journal Year: 2022, Volume and Issue: 4(3)

Published: Jan. 20, 2022

Abstract Grasslands are the most threatened and least protected biome. Yet, no study has been conducted to identify last remaining continuous grasslands on Earth. Here, we used World Wildlife Fund (WWF) International Union for Conservation of Nature (IUCN) classifications measure degree intactness world's grassland ecoregions. This analysis revealed three findings critical conservation importance. First, only a few large, intact remain. Second, every continent with ecoregion considered in this contains at one relatively ecoregion. Third, largest identified have persisted despite centuries anthropogenic pressures best chance withstand 21st century global change. We discuss how these regions importance efforts under anthropogenically driven They provide essential ecosystem services, play an important role mitigating effects climate change, serve as repositories biodiversity, foundational continental migration pathways, hold unique cultural heritage, people's livelihoods depend upon their persistence.

Language: Английский

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Droughts and the ecological future of tropical savanna vegetation

Journal of Ecology, Journal Year: 2019, Volume and Issue: 107(4), P. 1531 - 1549

Published: June 27, 2019

Abstract Climate change is expected to lead more frequent, intense and longer droughts in the future, with major implications for ecosystem processes human livelihoods. The impacts of such are already evident, vegetation dieback reported from a range ecosystems, including savannas, recent years. Most our insights into mechanisms governing drought responses have come forests temperate grasslands, while savannas received less attention. Because two life forms that dominate savannas—C 3 trees C 4 grasses—respond differently same environmental controls, savanna can differ those grasslands. Drought‐driven mortality not readily predicted by just plant drought‐tolerance traits alone, but net outcome multiple factors, drought‐avoidance strategies, landscape neighborhood context, past current stressors fire, herbivory inter‐life form competition. Many currently appear capacity recover moderate severe short‐term droughts, although recovery times be substantial. Factors facilitating include resprouting ability vegetation, enhanced flowering seeding post‐drought amelioration fire. Future increases severity, length frequency interrupt trajectories compositional shifts, thus pose substantial threats, particularly arid semi‐arid savannas. Synthesis . Our understanding of, predict, limited availability relevant data, there an urgent need campaigns quantifying drought‐survival across diverse Importantly, these must move beyond reliance on set functional identifying suites physiological, morphological, anatomical structural or “syndromes” encapsulate both avoidance tolerance strategies. There also critical global network long‐term monitoring sites as provide key factors influencing resistance resilience different droughts. Such efforts, coupled site‐specific rainfall manipulation experiments characterize trait–drought response relationships, modelling will enable comprehensive responses.

Language: Английский

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Historical Indigenous Land-Use Explains Plant Functional Trait Diversity

Ecology and Society, Journal Year: 2021, Volume and Issue: 26(2)

Published: Jan. 1, 2021

Armstrong, C., J. Miller, A. C. McAlvay, P. M. Ritchie, and D. Lepofsky. 2021. Historical Indigenous Land-Use Explains Plant Functional Trait Diversity. Ecology Society 26(2):6. https://doi.org/10.5751/ES-12322-260206

Language: Английский

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Floristic evidence for alternative biome states in tropical Africa

Proceedings of the National Academy of Sciences, Journal Year: 2020, Volume and Issue: 117(45), P. 28183 - 28190

Published: Oct. 27, 2020

Significance We develop a biogeographic approach to analyzing the presence of alternative stable states in tropical biomes. Whilst forest–savanna bistability has been widely hypothesized and modeled, empirical evidence remained scarce controversial, here, applying our method Africa, we provide large-scale that there are tree species composition vegetation. Furthermore, results have produced more accurate maps forest savanna distributions which take into account differences composition, complex suite determinants. This result is not only important for understanding biogeography continent but also, guide large-scaled planting restoration efforts planned region.

Language: Английский

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Encroachment diminishes herbaceous plant diversity in grassy ecosystems worldwide

Global Change Biology, Journal Year: 2022, Volume and Issue: 28(18), P. 5532 - 5546

Published: July 11, 2022

Abstract Woody encroachment is ubiquitous in grassy ecosystems worldwide, but its global impacts on the diversity of herbaceous plants that characterise and define these remain unquantified. The pervasiveness relatively easily observed via remote sensing, plant richness below canopy can only be field‐based studies. Via a meta‐analysis 42 field studies across tropical to temperate ecosystems, we quantified how altered species richness, forbs, C 3 graminoids 4 graminoids. Across studies, natural logarithm response ratio (lnRR) ranged from −3.33 0.34 with 87% encroached negatively impacted. Assessment extent encroachment, duration mean annual rainfall, latitude, continent demonstrated had relevance data (univariate model including random effect study explained 45.4% variance). weighted lnRR decreased −0.245 at <33% woody cover increase, −0.562 33%–66%, −0.962 >66%. Continued results substantial loss medium high extents, not replaced. Although all functional groups are significantly impacted by forb more sensitive than graminoid richness. no geographic or climatic correlates data, as an emergent product change coalesces decrease ground layer light availability, lead fire grazers, alter hydrology soils. Encroachment accelerating require urgent attention determine critical thresholds facilitate diverse resilient ecosystems.

Language: Английский

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