Morphological and Chemical Traits of Cladonia Respond to Multiple Environmental Factors in Acidic Dry Grasslands

Terricolous lichen communities in lowlands occur especially in open dry habitats. Such communities are often dominated by species of the genus Cladonia, which are very variable in morphology, reproduction strategies, and secondary metabolites. In this work, we investigated traits-environment relationships considering vegetation dynamics, substrate pH, disturbance, and climate. A total of 122 plots were surveyed in 41 acidic dry grasslands in the western Po Plain (Northern Italy). Relationships between Cladonia traits and environmental variables were investigated by means of a model-based Fourth Corner Analysis. Thallus morphology and metabolites responded to vegetation dynamics, substrate pH, disturbance, and climate, whereas reproduction strategies responded only to vegetation dynamics. Traits’ correlations with vegetation dynamics elucidate their colonization patterns in open dry habitats or suggest biotic interactions with bryophytes and vascular plants. In addition, correlations between metabolites and environmental factors support interpretations of their ecological roles. Our results also stress the importance of studying traits’ relationships with climatic factors as an alert towards lichen reactions to climate change.

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Longitudinal zonation of larval Hydropsyche (Trichoptera: Hydropsychidae): abiotic environmental factors and biotic interactions behind the downstream sequence of Central European species

Hydrobiologia ◽

10.1007/s10750-021-04602-0 ◽

2021 ◽

Author(s):

Márk Ficsór ◽

Zoltán Csabai

Keyword(s):

Environmental Factors ◽

Biotic Interactions ◽

Life Cycles ◽

Longitudinal Distribution ◽

Central European ◽

European Species ◽

Longitudinal Gradients ◽

Species Specific ◽

Behavioural Aspects ◽

Abiotic Environmental Factors

AbstractThe aim of this review is to summarize the literature knowledge about how abiotic environmental factors and biotic interactions affect the sequentially overlapping longitudinal distribution of Central European species of the net-spinning freshwater caddisfly larvae of the genus Hydropsyche (Trichoptera: Hydropsychidae). In this relation, several physical and chemical parameters of water are discussed, as well as different species-specific traits, behavioural aspects and the interaction of coexisting species. Longitudinal gradients of river networks, especially annual temperature range, flow velocity and the particle size of suspended food material play a crucial role in forming the downstream succession of characteristic species, while increased levels of organic pollution, nutrients, salinity and heavy metals facilitates the presence of more tolerant ones. Several species-specific traits, such as respiration range, net-building frequency, head capsule size or optimal net-building velocity correlate with the position of a given species in the sequence. Coexistence of species with similar ecological demands in the overlapping zones of distribution is facilitated by differences in feeding and net-building habits, microhabitat preferences and staggering life cycles, but complicated at the same time by means of inter- and intraspecific territorial behaviour, such as fighting for the ownership of larval retreats or the practice of stridulation.

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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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Disentangling the effects of hydro-climatic factors and land use intensification on wetland vegetation dynamics in the Lower Delta of the Paraná River

Remote Sensing Applications Society and Environment ◽

10.1016/j.rsase.2021.100466 ◽

2021 ◽

Vol 21 ◽

pp. 100466

Author(s):

Diego Sebastián Aquino ◽

Gregorio Gavier-Pizarro ◽

Rubén Darío Quintana

Keyword(s):

Land Use ◽

Vegetation Dynamics ◽

Climatic Factors ◽

Paraná River ◽

Wetland Vegetation ◽

Parana River ◽

Land Use Intensification

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Hierarchy of environmental factors driving restoration of dry grasslands: A multi‐site analysis

Applied Vegetation Science ◽

10.1111/avsc.12576 ◽

2021 ◽

Vol 24 (2) ◽

Author(s):

Karel Prach ◽

Karel Fajmon ◽

Klára Řehounková ◽

Ivana Jongepierová

Keyword(s):

Environmental Factors ◽

Site Analysis ◽

Dry Grasslands

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Multi-Year NDVI Values as Indicator of the Relationship between Spatiotemporal Vegetation Dynamics and Environmental Factors in the Qaidam Basin, China

Remote Sensing ◽

10.3390/rs13071240 ◽

2021 ◽

Vol 13 (7) ◽

pp. 1240

Author(s):

Junpeng Lou ◽

Guoyin Xu ◽

Zhongjing Wang ◽

Zhigang Yang ◽

Sanchuan Ni

Keyword(s):

Environmental Factors ◽

Vegetation Dynamics ◽

Vegetation Index ◽

Qaidam Basin ◽

Elevation Gradient ◽

Practical Significance ◽

Elevation Gradients ◽

Relative Contribution ◽

Significant Difference ◽

Different Altitudes

The Qaidam Basin is a unique and complex ecosystem, wherein elevation gradients lead to high spatial heterogeneity in vegetation dynamics and responses to environmental factors. Based on the remote sensing data of Moderate Resolution Imaging Spectroradiometer (MODIS), Tropical Rainfall Measuring Mission (TRMM) and Global Land Data Assimilation System (GLDAS), we analyzed the spatiotemporal variations of vegetation dynamics and responses to precipitation, accumulative temperature (AT) and soil moisture (SM) in the Qaidam Basin from 2001 to 2016. Moreover, the contribution of those factors to vegetation dynamics at different altitudes was analyzed via an artificial neural network (ANN) model. The results indicated that the Normalized Difference Vegetation Index (NDVI) values in the growing season showed an overall upward trend, with an increased rate of 0.001/year. The values of NDVI in low-altitude areas were higher than that in high-altitude areas, and the peak values of NDVI appeared along the elevation gradient at 4400–4600 m. Thanks to the use of ANN, we were able to detect the relative contribution of various environmental factors; the relative contribution rate of AT to the NDVI dynamic was the most significant (35.17%) in the low-elevation region (< 2900 m). In the mid-elevation area (2900–3900 m), precipitation contributed 44.76% of the NDVI dynamics. When the altitude was higher than 3900 m, the relative contribution rates of AT (39.50%) and SM (38.53%) had no significant difference but were significantly higher than that of precipitation (21.97%). The results highlight that the different environmental factors have various contributions to vegetation dynamics at different altitudes, which has important theoretical and practical significance for regulating ecological processes.

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Environmental influences on fish and shellfish production in the Northwest Atlantic

Environmental Reviews ◽

10.1139/a94-002 ◽

1994 ◽

Vol 2 (1) ◽

pp. 16-32 ◽

Cited By ~ 36

Author(s):

K.H. Mann ◽

K.F. Drinkwater

Keyword(s):

Environmental Factors ◽

Gadus Morhua ◽

Cold Water ◽

Climatic Factors ◽

Homarus Americanus ◽

Fishing Mortality ◽

Poor Growth ◽

Northwest Atlantic ◽

Grand Banks ◽

Fish And Shellfish

Evidence is reviewed, linking physical oceanographic processes in the marine environment to changes in fish and shellfish stocks in the Northwest Atlantic. A case history study of the cod (Gadus morhua) stock of the northern Grand Banks and Labrador Shelf indicates a long slow amelioration of the environment between about 1945 and 1965, followed by a deterioration in the period 1965–1992. The most important environmental factors for the cod stocks appear to have been salinity and temperature. The trends can be traced back to climatic factors involving the Icelandic Low and the Azores–Bermuda High. When the atmospheric pressure difference in winter tended to be high, there was a progressive increase in the area of sea ice off Labrador and in the volume of cold water at depth. These factors have been shown to affect temperature and salinity conditions on the Grand Banks in spring and summer and are associated with poor growth and recruitment in the cod stocks. A similar case study of lobster (Homarus americanus) stocks indicates that temperature and river discharge are important environmental correlates, but neither can be shown to fully account for the recent trends in the stocks. Evidence is reviewed to show that physical environmental processes also influence recruitment and distribution of stocks of haddock, capelin, and squid. Some of the problems with correlational analysis are also discussed. It is recognized that factors other than the environment are influencing the stocks. Fishing mortality (detailed consideration of which is not included in this review) has clearly been important. Interactions between environmental factors and fishing mortality are probably of major importance.Key words: ocean environment, fish production, recruitment, northern cod, American lobster.

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An inter-dependence of flood and drought: disentangling amphibian beta diversity in seasonal floodplains

Marine and Freshwater Research ◽

10.1071/mf16391 ◽

2017 ◽

Vol 68 (11) ◽

pp. 2115 ◽

Cited By ~ 2

Author(s):

Leonardo F. B. Moreira ◽

Tainá F. Dorado-Rodrigues ◽

Vanda L. Ferreira ◽

Christine Strüssmann

Keyword(s):

Community Structure ◽

Environmental Factors ◽

Quantitative Data ◽

Explanatory Variable ◽

Biotic Interactions ◽

Ecological Role ◽

Β Diversity ◽

Amphibian Community ◽

Dry Seasons

Species composition in floodplains is often affected by different structuring factors. Although floods play a key ecological role, habitat selection in the dry periods may blur patterns of biodiversity distribution. Here, we employed a partitioning framework to investigate the contribution of turnover and nestedness to β-diversity patterns in non-arboreal amphibians from southern Pantanal ecoregion. We investigated whether components of β-diversity change by spatial and environmental factors. We sampled grasslands and dense arboreal savannas distributed in 12 sampling sites across rainy and dry seasons, and analysed species dissimilarities using quantitative data. In the savannas, both turnover and nestedness contributed similarly to β diversity. However, we found that β diversity is driven essentially by turnover, in the grasslands. In the rainy season, balanced variation in abundance was more related to altitude and factors that induce spatial patterns, whereas dissimilarities were not related to any explanatory variable during dry season. In the Pantanal ecoregion, amphibian assemblages are influenced by a variety of seasonal constraints on terrestrial movements and biotic interactions. Our findings highlighted the role of guild-specific patterns and indicated that mass effects are important mechanisms creating amphibian community structure in the Pantanal.

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REDUCING THE INFLUENCE OF ENVIRONMENTAL FACTORS ON THE BENDING DEFORMATION OF CURED CARBON FIBER BY MICROWAVE PROCESSING

IZVESTIA VOLGOGRAD STATE TECHNICAL UNIVERSITY ◽

10.35211/1990-5297-2021-2-249-56-58 ◽

2021 ◽

pp. 56-58

Author(s):

I. V. Zlobina

Keyword(s):

Electromagnetic Field ◽

Composite Materials ◽

Carbon Fiber ◽

Environmental Factors ◽

Flux Density ◽

Environmental Conditions ◽

Climatic Factors ◽

Transverse Load ◽

Bending Deformation ◽

Energy Flux Density

The article discusses the results of a study of bending deformation and creep under transverse load of cured polymer composite materials (PCM), which were located for 8 months in full-scale environmental conditions in Saratov. It was found that being under the influence of natural climatic factors for the specified time leads to an increase in the bending deformation of samples from 13,5 to 25,4%, depending on the load. Processing in a microwave electromagnetic field with a frequency of 2450 MHz with an energy flux density of (17-18) x10 mW / cm for 2 minutes reduces bending deformation by (9-18)%, and creep - up to 4 times.

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Biodiversity and conservation of terricolous lichens and bryophytes in continental lowlands of northern Italy: the role of different dry habitat types

Biodiversity and Conservation ◽

10.1007/s10531-020-02034-1 ◽

2020 ◽

Vol 29 (13) ◽

pp. 3533-3550

Author(s):

Gabriele Gheza ◽

Silvia Assini ◽

Chiara Lelli ◽

Lorenzo Marini ◽

Helmut Mayrhofer ◽

...

Keyword(s):

Species Richness ◽

Vegetation Dynamics ◽

Biodiversity Loss ◽

Northern Italy ◽

Environmental Drivers ◽

Dry Grasslands ◽

Species Of Conservation Concern ◽

Terricolous Lichens ◽

Landscape Scales

Abstract In dry habitats of European lowlands terricolous lichens and bryophytes are almost neglected in conservation practises, even if they may strongly contribute to biodiversity. This study aims at (a) testing the role of heathlands, acidic and calcareous dry grasslands for lichen and bryophyte diversity and conservation in lowland areas of northern Italy characterized by high human impact and habitat fragmentation; (b) detecting the effect of environmental drivers and vegetation dynamics on species richness and composition. Lichens, bryophytes, vascular plants, and environmental variables were recorded in 287 circular plots for 75 sites. Our results indicate that heathlands, acidic and calcareous dry grasslands host peculiar terricolous lichen and bryophyte communities that include several species of conservation concern. Thus, each habitat provides a complementary contribution to lichen and bryophyte diversity in continental lowland landscapes. Furthermore, in each habitat different factors drive species richness and composition with contrasting patterns between lichens and bryophytes. In terms of conservation, our results indicate that management of lowland dry habitats should act at both local and landscape scales. At local scale, vegetation dynamics should be controlled in order to avoid biodiversity loss due to vegetation dynamics and wood encroachment. At the landscape scale, patches of all the three habitats should be maintained to maximize regional diversity.

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