scholarly journals Antagonistic effect of natural habitat conversion on community adjustment to climate warming in nonbreeding waterbirds

2020 ◽  
Vol 34 (4) ◽  
pp. 966-976 ◽  
Author(s):  
Elie Gaget ◽  
Thomas Galewski ◽  
Frédéric Jiguet ◽  
Anis Guelmami ◽  
Christian Perennou ◽  
...  
Keyword(s):  
Climate Warming ◽  
Natural Habitat ◽  
Antagonistic Effect ◽  
Community Adjustment ◽  
Habitat Conversion

scholarly journals Volatile metabolites of endophytic Klebsiella aerogenes from Zingiber zerumbet rhizome and its antagonistic effect on soft rot causative Pythium myriotylum

2020 ◽  
pp. 122-132
Author(s):  
K. Harsha ◽  
R. Aswati Nair
Keyword(s):  
Ethyl Acetate ◽  
Methyl Esters ◽  
Natural Habitat ◽  
Ethanol Extract ◽  
Soft Rot ◽  
Antagonistic Effect ◽  
Absolute Methanol ◽  
Potential Candidate ◽  
Zingiber Zerumbet ◽  
Volatile Metabolites

Rhizomes of Zingiber zerumbet collected from their natural habitat and reported earlier to have high zerumbone content were selected for isolation of endophytes. Biochemical and molecular characterization using 16S rRNA sequencing of the endophytes identified the isolates as belonging to genus Klebsiella, Pantoea and Enterobacter. Isolate designated ZzKSD8 identified as K. aerogenes yielded maximal antagonistic activities against P. myriotylum determined as 83.5% ± 0.77. Volatile metabolites produced by ZzKSD8 caused absolute impairment of P. myriotylum hyphal growth compared to control (23.9 ± 0.37 cm). Volatile metabolites were extracted from 48 hour grown stationary phase ZzKSD8 cultures using absolute methanol, ethyl acetate and ethanol (60% v/v). GC-MS metabolite profiling detected alkanes and fatty acid methyl esters as the predominant constituents in the solvent extracts. Major constituents included methyl palmitate (31.37%), methyl stearate (18.57%) and cyclopropaneoctanoic acid, 2-hexyl-, methyl ester (17.05%) in methanol extract; alkanes like tetratetracontane (13.18%) and 2-methyloctacosane (12.10%) in ethyl acetate extracts and 4,22-sigmastadiene-3-one as major metabolite (22.51%) and stigmast-5-en-3-ol, (3.beta) (17.40%) in ethanol extract. Identified metabolites reported to modulate defense strategies in plants against phytopathogens makes ZzKSD8 a potential candidate for development of biological alternatives to control soil-borne soft-rot disease.

scholarly journals Non-breeding waterbirds benefit from protected areas when adjusting their distribution to climate warming

2021 ◽  
Author(s):  
Elie Gaget ◽  
Diego Pavón-Jordán ◽  
Alison Johnston ◽  
Aleksi Lehikoinen ◽  
Wesley M. Hochachka ◽  
...  
Keyword(s):  
Protected Areas ◽  
Climate Warming ◽  
Species Distribution ◽  
Temperature Increase ◽  
Species Distributions ◽  
Community Change ◽  
Species Extinction ◽  
Distribution Change ◽  
Community Adjustment ◽  
Western Palearctic

AbstractClimate warming is driving changes in species distributions, although many species show a so-called climatic debt, where their range shifts lag behind the fast shift in temperature isoclines. Protected areas (PAs) may impact the rate of distribution changes both positively and negatively. At the cold edges of species distributions, PAs can facilitate species distribution changes by increasing the colonization required for distribution change. At the warm edges, PAs can mitigate the loss of species, by reducing the local extinction of vulnerable species. To assess the importance of PAs to affect species distribution change, we evaluated the changes in a non-breeding waterbird community as a response to temperature increase and PA status, using changes of species occurrence in the Western-Palearctic over 25 years (97 species, 7,071 sites, 39 countries, 1993– 2017). We used a community temperature index (CTI) framework based on species thermal affinities to investigate the species turn-over induced by temperature increase. In addition, we measured whether the thermal community adjustment was led by cold-dwelling species extinction and/or warm-dwelling species colonization, by modelling the change in standard deviation of the CTI (CTIsd). Using linear mixed-effects models, we investigated whether communities within PAs had lower climatic debt and different patterns of community change regarding the local PA surface. Thanks to the combined use of the CTI and CTIsd, we found that communities inside PAs had more species, higher colonization, lower extinction and the climatic debt was 16% lower than outside PAs. The results suggest the importance of PAs to facilitate warm-dwelling species colonization and attenuate cold-dwelling species extinction. The community adjustment was however not sufficiently fast to keep pace with the strong temperature increase in central and northeastern Western-Palearctic regions. Our study underlines the potential of the combined CTI and CTIsd metrics to understand the colonization-extinction patterns driven by climate warming.

scholarly journals Climate warming caused changes in the bud swelling phenophase of introduced conifer species, considering the aspect of hardiness zones in their natural habitats

Biologija ◽  
2017 ◽  
Vol 63 (2) ◽  
Author(s):  
Asta Malakauskienė ◽  
Adomas Vitas
Keyword(s):  
Climate Warming ◽  
Natural Habitat ◽  
Botanical Garden ◽  
Climatic Conditions ◽  
Taxus Baccata ◽  
Conifer Species ◽  
Natural Habitats ◽  
Start Date ◽  
Tree Phenology

Background. Changing climatic conditions cause changes in tree phenology, which is important for the survival of species and their spread in local ecosystems. This study concentrated on long-term (1957–2016 or 1980–2016) observations of 11 conifer species introduced to Lithuania with the aim to evaluate the response of their bud swelling phenophase to climate warming, considering the hardiness zones of their natural habitats. Materials and Methods. Sequences of the start date of the bud swelling phenophase of 11 introduced conifer species (Abies veitchii, Larix decidua, L. kaempferi, L. laricina, L. × marschlinsii, L. sibirica, L. sukaczewii, Picea mariana, Pinus mugo, Taxus baccata and Thuja occidentalis) were analysed. Data were collected from the paper archives of Kaunas Botanical Garden of Vytautas Magnus University (VMU). Sequences of bud swelling start dates were transformed into sequences of number of days from the beginning of the year. Results. Results indicated an advance of the bud swelling phenophase of ten conifer species introduced to Lithuania (the speed of changes varied from –0.10 to –0.98 days/year in the 1980–2016 period) and a delay of Larix sukaczewii (respectively, +0.12 days/ year) of the bud swelling phenophase, mainly influenced by the March temperature. Conclusions. The connection between the observed conifer species hardiness zone of the natural habitat and the reaction of the bud swelling phenophase to climate warming could be observed only when species from one genus were compared. To confirm this phenomenon, a research on a larger amount of introduced species with wider habitat hardiness zone options is needed in future.

scholarly journals Effects of Habitat Conversion on Ant Functional Groups: A Global Review

Sociobiology ◽  
2021 ◽  
Vol 68 (2) ◽  
pp. 6071
Author(s):  
Roberta De Jesus Santos ◽  
Pavel Dodonov ◽  
Jacques Hubert C. Delabie
Keyword(s):  
Functional Groups ◽  
Environmental Changes ◽  
Natural Habitat ◽  
Cold Climate ◽  
Ecological Niches ◽  
Land Conversion ◽  
Tropical Regions ◽  
Hot Climate ◽  
Habitat Conversion ◽  
The Tropics

Conversion of natural to anthropogenic environments affects biodiversity, and the understanding of these impacts may be improved by assessing how different functional groups respond to such land conversion. We studied land conversion impacts on ant functional groups, as ants are ecologically important and respond well to various environmental changes. We hypothesized that conversion of natural to anthropogenic environments modifies the composition of functional groups, fostering generalist and opportunistic groups over specialist ones, with more responses of this type in tropical than in temperate regions. We recovered 412 papers from ISI Web of Science, of which we selected 17 studies, published between 1993 and 2018, that addressed our study’s question. We assessed whether each functional group responded positively or negatively to conversion of natural habitat into anthropogenic land uses and used Monte Carlo tests to assess significance. Ants were affected by natural habitat conversion into monoculture and polyculture and by the conversion of savannas and of tropical and subtropical forests. Land conversion affected six of the 13 functional groups assessed here. In the temperate zone, cryptic species, predators, subordinate Camponotini, cold-climate specialists and tropical-climate specialists were impaired, whereas hot-climate specialists were favored. In the tropics, land conversion negatively impacted fungus-growers and predators. In both climatic zones, several functional groups, mainly those with broad ecological niches, did not respond to land conversion. Our results corroborate that land conversion effects vary among ant functional groups and indicate that the ant fauna of temperate ecosystems may be more susceptible than that of tropical regions.

Effect of Iron Limitation on the Ultrastructure of Agmenellum Quadruplicatum

1981 ◽  
Vol 39 ◽  
pp. 410-411
Author(s):  
L. P. Hardie ◽  
D. L. Balkwill ◽  
S. E. Stevens
Keyword(s):  
Growth Medium ◽  
Green Alga ◽  
Natural Habitat ◽  
Iron Limitation ◽  
Natural Environments ◽  
Blue Green Alga ◽  
Marine Cyanobacterium ◽  
Natural Systems ◽  
Thin Sectioning ◽  
Agmenellum Quadruplicatum

Agmenellum quadruplicatum is a unicellular, non-nitrogen-fixing, marine cyanobacterium (blue-green alga). The ultrastructure of this organism, when grown in the laboratory with all necessary nutrients, has been characterized thoroughly. In contrast, little is known of its ultrastructure in the specific nutrient-limiting conditions typical of its natural habitat. Iron is one of the nutrients likely to limit this organism in such natural environments. It is also of great importance metabolically, being required for both photosynthesis and assimilation of nitrate. The purpose of this study was to assess the effects (if any) of iron limitation on the ultrastructure of A. quadruplicatum. It was part of a broader endeavor to elucidate the ultrastructure of cyanobacteria in natural systemsActively growing cells were placed in a growth medium containing 1% of its usual iron. The cultures were then sampled periodically for 10 days and prepared for thin sectioning TEM to assess the effects of iron limitation.

THE CLASSIFICATION OF LAND ACCORDING TO THE DEGREE OF RABBIT INFESTATION IN CENTRAL OTAGO

1987 ◽  
pp. 65-70
Author(s):  
I.G.C. Kerr ◽  
J.M. Williams ◽  
W.D. Ross ◽  
J.M. Pollard
Keyword(s):  
Carrying Capacity ◽  
Mediterranean Climate ◽  
Natural Habitat ◽  
Public Funding ◽  
Soil Survey ◽  
European Rabbit ◽  
Cultural Modification ◽  
Classification Information ◽  
Semi Arid

The European rabbit (Oryctolagus cuniculus) introduced into New Zealand in the 183Os, has consistently flourished in Central Otago, the upper Waitaki, and inland Marlborough, all areas of mediterranean climate. It has proved difficult to manage in these habitats. The 'rabbit problem' is largely confined to 105,000 ha of low producing land mostly in semi arid areas of Central Otago. No field scale modifications of the natural habitat have been successful in limiting rabbit numbers. The costs of control exceed the revenue from the land and continued public funding for control operations appears necessary. A system for classifying land according to the degree of rabbit proneness is described. Soil survey and land classification information for Central Otago is related to the distribution and density of rabbits. This intormation can be used as a basis for defining rabbit carrying capacity and consequent land use constraints and management needs. It is concluded that the natural rabbit carrying capacity of land can be defined by reference to soil survey information and cultural modification to the natural vegetation. Classification of land according to rabbit proneness is proposed as a means of identifying the need for, and allocation of, public funding tor rabbit management. Keywords: Rabbit habitat, rabbit proneness, use of rabbit prone land.

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