Impacts of climatic variability and extreme on forests: synthesis

ABSTRACT Understanding the impacts of agricultural practices on soil quality indicators, such as enzymatic activities, is of great importance, in order to advance in their diagnosis and sustainable management. This study aimed to evaluate the effect of ecological and conventional agricultural managements on enzymatic activities of a soil under coffee agroecosystems. The enzymatic activities were associated with the biogeochemical cycles of nitrogen (urease and protease), phosphorus (acid and alkaline phosphatase) and carbon (β-glucosidase), during the rainy and dry seasons. Physical-chemical soil proprieties were also assessed and related to resilience scores linked to the climatic variability reported for the areas under study. The activities of urease, alkaline and acid phosphatase and ß-glucosidase were statistically higher in ecological agroecosystems than in conventional ones. This may be attributed to the greater application of organic waste in the ecological environment, as well as to the absence of pesticides and synthetic fertilizers, which allow better conditions for the microbial activity. The resilience scores to the climate variability that showed the highest correlations with the assessed enzymatic activities were: the farmers' knowledge on soil microorganisms, non-use of pesticides and synthetic fertilizers and non-dependence on external supplies. It was concluded that the enzymatic activities are modified by the management systems, being specifically favored by the ecological management. This agroecosystem, in the long term, ensures an efficient use of the soil resources, with a lower degradation and contamination.

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What evidence exists on the impacts of flow variability on fish and macroinvertebrates of temperate floodplain rivers in Central and Western Europe? A systematic map protocol

Environmental Evidence ◽

10.1186/s13750-021-00225-z ◽

2021 ◽

Vol 10 (1) ◽

Author(s):

Agata Keller ◽

Somsubhra Chattopadhyay ◽

Mikołaj Piniewski

Keyword(s):

Climate Change ◽

Western Europe ◽

Climatic Variability ◽

Grey Literature ◽

Habitat Type ◽

Water Diversion ◽

Systematic Map ◽

Eligibility Criteria ◽

Flow Variability ◽

Floodplain Rivers

Abstract Background Flow variability is considered a fundamental factor affecting riverine biota. Any alterations to flow regime can influence freshwater organisms, and this process is expected to change with the projected climate change. This systematic map, therefore, aims at investigating the impacts of natural (resulting from climatic variability), anthropogenic (resulting from direct human pressure), and climate change-induced flow variability on fish and macroinvertebrates of temperate floodplain rivers in Central and Western Europe. Particular focus will be placed on the effects of extreme low and high discharges. These rare events are known to regulate population size and taxonomic diversity. Methods All studies investigating the effects of flow variability on metrics concerning freshwater fish and macroinvertebrates will be considered in the map, particularly metrics such as: abundance, density, diversity, growth, migration, recruitment, reproduction, survival, or their substitutes, such as biomonitoring indices. Relevant flow variability will reflect (1) anthropogenic causes: dams, reservoirs, hydroelectric facilities, locks, levees, water abstraction, water diversion, land-use changes, road culverts; (2) natural causes: floods, droughts, seasonal changes; or (3) climate change. Geographically, the map will cover the ecoregion of Central and Western Europe, focusing on its major habitat type, namely “temperate floodplain rivers and wetlands”. The review will employ search engines and specialist websites, and cover primary and grey literature. No date, language, or document type restrictions will be applied in the search strategy. We expect the results to be primarily in English, although evidence (meeting all eligibility criteria) from other languages within the study area will also be included. We will also contact relevant stakeholders and announce an open call for additional information. Eligibility screening will be conducted at two levels: title and abstract, and full text. From eligible studies the following information will be extracted: the cause of flow variability, location, type of study, outcomes, etc. A searchable database containing extracted data will be developed and provided as supplementary material to the map report. The final narrative will describe the quantity and key characteristics of the available evidence, and identify knowledge gaps and knowledge clusters, i.e. subtopics sufficiently covered by existing studies allowing full systematic review and meta-analysis.

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Demographic effects of interacting species: exploring stable coexistence under increased climatic variability in a semiarid shrub community

Scientific Reports ◽

10.1038/s41598-021-82571-z ◽

2021 ◽

Vol 11 (1) ◽

Author(s):

Ana I. García-Cervigón ◽

Pedro F. Quintana-Ascencio ◽

Adrián Escudero ◽

Merari E. Ferrer-Cervantes ◽

Ana M. Sánchez ◽

...

Keyword(s):

Population Dynamics ◽

Species Coexistence ◽

Climatic Factors ◽

Demographic Data ◽

Climatic Variability ◽

Biotic Interactions ◽

Vital Rates ◽

Climatic Fluctuations ◽

Demographic Models ◽

Shrub Community

AbstractPopulation persistence is strongly determined by climatic variability. Changes in the patterns of climatic events linked to global warming may alter population dynamics, but their effects may be strongly modulated by biotic interactions. Plant populations interact with each other in such a way that responses to climate of a single population may impact the dynamics of the whole community. In this study, we assess how climate variability affects persistence and coexistence of two dominant plant species in a semiarid shrub community on gypsum soils. We use 9 years of demographic data to parameterize demographic models and to simulate population dynamics under different climatic and ecological scenarios. We observe that populations of both coexisting species may respond to common climatic fluctuations both similarly and in idiosyncratic ways, depending on the yearly combination of climatic factors. Biotic interactions (both within and among species) modulate some of their vital rates, but their effects on population dynamics highly depend on climatic fluctuations. Our results indicate that increased levels of climatic variability may alter interspecific relationships. These alterations might potentially affect species coexistence, disrupting competitive hierarchies and ultimately leading to abrupt changes in community composition.

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The sensitivity of Neotoma to climate change and biodiversity loss over the late Quaternary

Quaternary Research ◽

10.1017/qua.2021.29 ◽

2021 ◽

pp. 1-15

Author(s):

Catalina P. Tomé ◽

S. Kathleen Lyons ◽

Seth D. Newsome ◽

Felisa A. Smith

Keyword(s):

Body Size ◽

Late Quaternary ◽

Climatic Variability ◽

Isotope Analysis ◽

Biodiversity Loss ◽

Bone Collagen ◽

Cam Plants ◽

The Holocene ◽

Carbon And Nitrogen ◽

Terminal Pleistocene

Abstract The late Quaternary in North America was marked by highly variable climate and considerable biodiversity loss including a megafaunal extinction event at the terminal Pleistocene. Here, we focus on changes in body size and diet in Neotoma (woodrats) in response to these ecological perturbations using the fossil record from the Edwards Plateau (Texas) across the past 20,000 years. Body mass was estimated using measurements of fossil teeth and diet was quantified using stable isotope analysis of carbon and nitrogen from fossil bone collagen. Prior to ca. 7000 cal yr BP, maximum mass was positively correlated to precipitation and negatively correlated to temperature. Independently, mass was negatively correlated to community composition, becoming more similar to modern over time. Neotoma diet in the Pleistocene was primarily sourced from C3 plants, but became progressively more reliant on C4 (and potentially CAM) plants through the Holocene. Decreasing population mass and higher C4/CAM consumption was associated with a transition from a mesic to xeric landscape. Our results suggest that Neotoma responded to climatic variability during the terminal Pleistocene through changes in body size, while changes in resource availability during the Holocene likely led to shifts in the relative abundance of different Neotoma species in the community.

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A palaeoenvironmental record of the Southern Hemisphere last glacial maximum from the Mount Cass loess section, North Canterbury, Aotearoa/New Zealand

Quaternary Research ◽

10.1017/qua.2020.95 ◽

2020 ◽

pp. 1-15

Author(s):

Peter C. Almond ◽

Sándor Gulyás ◽

Pál Sümegi ◽

Balázs P. Sümegi ◽

Stephen Covey-Crump ◽

...

Keyword(s):

New Zealand ◽

Southern Hemisphere ◽

Last Glacial Maximum ◽

Climatic Variability ◽

Glacial Maximum ◽

Pollen Record ◽

Good Correspondence ◽

Last Glacial ◽

Event Stratigraphy ◽

Westerly Winds

Abstract Calcareous loess in North Canterbury, eastern South Island, New Zealand (NZ), preserves subfossil bird bone, terrestrial gastropods, and eggshell, whose abundances and radiocarbon ages allowed us to reconstruct aspects of palaeoenvironment at high resolution through 25 to 21 cal ka BP. This interval includes millennial-scale climatic variability during the extended last glacial maximum (30–18 ka) of Australasia. Our loess palaeoclimatic record shows good correspondence with stadial and interstadial climate events of the NZ Climate Event Stratigraphy, which were defined from a pollen record on the western side of South Island. An interstade from 25.4 to 24 cal ka BP was warm but also relatively humid on eastern South Island, and loess grain size may indicate reduced vigour of the Southern Hemisphere westerly winds. The subsequent stade (24–22.6 cal ka BP) was drier, colder, and probably windier. The next interstade remained relatively dry on eastern South Island, and westerly winds remained vigorous. The 25.4–24 ka interstade is synchronous with Heinrich stade 2, which may have driven a southward migration of the subtropical front, leading to warming and wetting of northern and central South Island and retreat of Southern Alps glaciers at ca. 26.5 ka.

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Beyond elevation: testing the climatic variability hypothesis vs. Rapoport’s rule in vascular plant and snail species in the Caucasus

Biological Journal of the Linnean Society ◽

10.1093/biolinnean/blx027 ◽

2017 ◽

Vol 121 (4) ◽

pp. 753-763 ◽

Cited By ~ 6

Author(s):

Levan Mumladze ◽

Zezva Asanidze ◽

Frank Walther ◽

Bernhard Hausdorf

Keyword(s):

Climatic Variability ◽

Vascular Plant ◽

Snail Species ◽

The Caucasus ◽

Rapoport’S Rule ◽

Climatic Variability Hypothesis

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An ecological niche shift for Neanderthal populations in Western Europe 70,000 years ago

Scientific Reports ◽

10.1038/s41598-021-84805-6 ◽

2021 ◽

Vol 11 (1) ◽

Author(s):

William E. Banks ◽

Marie-Hélène Moncel ◽

Jean-Paul Raynal ◽

Marlon E. Cobos ◽

Daniel Romero-Alvarez ◽

...

Keyword(s):

Material Culture ◽

Ecological Niche ◽

Western Europe ◽

Ecological Niche Modeling ◽

Climatic Variability ◽

Niche Shift ◽

Ecological Niches ◽

Middle Paleolithic ◽

Niche Dynamics ◽

Anatomically Modern Humans

AbstractMiddle Paleolithic Neanderthal populations occupied Eurasia for at least 250,000 years prior to the arrival of anatomically modern humans. While a considerable body of archaeological research has focused on Neanderthal material culture and subsistence strategies, little attention has been paid to the relationship between regionally specific cultural trajectories and their associated existing fundamental ecological niches, nor to how the latter varied across periods of climatic variability. We examine the Middle Paleolithic archaeological record of a naturally constrained region of Western Europe between 82,000 and 60,000 years ago using ecological niche modeling methods. Evaluations of ecological niche estimations, in both geographic and environmental dimensions, indicate that 70,000 years ago the range of suitable habitats exploited by these Neanderthal populations contracted and shifted. These ecological niche dynamics are the result of groups continuing to occupy habitual territories that were characterized by new environmental conditions during Marine Isotope Stage 4. The development of original cultural adaptations permitted this territorial stability.

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