Ecology of cultivable yeasts in pristine forests in northern Patagonia (Argentina) influenced by different environmental factors

2014 ◽  
Vol 60 (6) ◽  
pp. 371-382 ◽  
Author(s):  
María Cecilia Mestre ◽  
Sonia Fontenla ◽  
Carlos A. Rosa

Environmental factors influencing the occurrence and community structure of soil yeasts in forests are not well studied. There are few studies dedicated to Southern Hemisphere soil yeasts populations and even fewer focused on temperate forests influenced by volcanic activity. The present work aimed to study the ecology of soil yeast communities from pristine forests influenced by different environmental factors (precipitation, physicochemical properties of soil, tree species, soil region, and season). The survey was performed in 4 northern Patagonian forests: 2 dominated by Nothofagus pumilio and 2 by Nothofagus antarctica. Yeast communities were described with ecological indices and species accumulation curves, and their association with environmental characteristics was assessed using multivariate analysis. Each forest site showed a particular arrangement of species as a result of environmental characteristics, such as dominant plant species, nutrient availability, and climatic characteristics. Cryptococcus podzolicus was most frequently isolated in nutrient-rich soils, Trichosporon porosum dominated cold mountain forests with low nutrient and water availability in soil, and capsulated yeasts such as Cryptococcus phenolicus dominated forest sites with low precipitation. The present work suggests that environmental factors affecting yeast communities may not be the current soil characteristics but the result of complex interactions of factors including natural disturbances like volcanic activity.

2020 ◽  
Vol 169 ◽  
pp. 102915 ◽  
Author(s):  
L.M. Martínez Álvarez ◽  
L.A.M. Ruberto ◽  
J.M. Gurevich ◽  
W.P. Mac Cormack

2020 ◽  
Vol 30 (Supplement_5) ◽  
Author(s):  
◽  

Abstract Autism is a set of heterogeneous neurodevelopmental conditions, characterised by early-onset difficulties in social communication and restricted, repetitive behaviour and interests. The worldwide population prevalence is about 1% with an increasing incidence and prevalence rates. Autism affects more male than female individuals, and comorbidity is common (>70% have concurrent conditions). Determinants of these changes in incidence and prevalence rates may also be related to exposure to environmental factors and to modifications in diagnostic concepts and criteria. In spite of the uncertainty in determinants of incidence of autisms, there is evidence that environmental characteristics play a significant role both as autism risk factors and as potential obstacles that influence the capabilities of autonomously and fully “using” everyday spaces. The workshop aims to provide a framework on risk factors of autism and explore the relationship with the built environment, focusing on the quality of the everyday spaces and projecting the effects that it could have in the long term on achieving a desirable level of quality of life. The 11th Sustainable Development Goals of United Nations “Make cities inclusive, safe, resilient and sustainable” underlines the necessity of designing policies and projects acting to enhance and promote healthy cities and communities by addressing the needs of the most vulnerable groups of inhabitants. Herewith we bring together the discipline of Public Health and Urban Design to promote an interdisciplinary debate on a little explored topic investigating how the approaches adopted during childhood to promote the wellbeing of people with ASD can be related or strengthen by focusing also on built environment design intervention to pursue and reach the same objectives even during adulthood. The workshop will consist of four presentations. The first focuses on giving an overview on current knowledge of intervention for people with autism, presenting also criteria for evidence-based interventions. The second explores the relationship between autism and built environment by providing an exhaustive framework of the available research literature in order to identify a first set of spatial requirements for autism friendly cities. The third examines the impact of built environment on ASD users with the aim of developing a specific evaluation tool for healthcare spaces and best practices formulation according to the specific sensorial hypo- or hyper-activation of people with autism. Finally, the fourth reports the results of a two years Research & Development project called “GAP REDUCE” finalized at developing an Assistive Technology tool to support people with ASD, adult and high-functioning, to plan urban itineraries towards daily destinations. Key messages World's incidence of autism is about 1% with an increasing incidence whose determining rates may also be related to environmental factors and to modifications in diagnostic concepts and criteria. Environmental characteristics play a significant role also as potential obstacles that influence the capabilities of people with autism of autonomously and fully “using” everyday spaces.


Author(s):  
Maame Esi Hammond ◽  
Radek Pokorný ◽  
Daniel Okae-Anti ◽  
Augustine Gyedu ◽  
Irene Otwuwa Obeng

AbstractThe positive ecological interaction between gap formation and natural regeneration has been examined but little research has been carried out on the effects of gaps on natural regeneration in forests under different intensities of disturbance. This study evaluates the composition, diversity, regeneration density and abundance of natural regeneration of tree species in gaps in undisturbed, intermittently disturbed, and disturbed forest sites. Bia Tano Forest Reserve in Ghana was the study area and three gaps each were selected in the three forest site categories. Ten circular subsampling areas of 1 m2 were delineated at 2 m spacing along north, south, east, and west transects within individual gaps. Data on natural regeneration < 350 cm height were gathered. The results show that the intensity of disturbance was disproportional to gap size. Species diversity differed significantly between undisturbed and disturbed sites and, also between intermittently disturbed and disturbed sites for Simpson’s (1-D), Equitability (J), and Berger–Parker (B–P) indices. However, there was no significant difference among forest sites for Shannon diversity (H) and Margalef richness (MI) indices. Tree species composition on the sites differed. Regeneration density on the disturbed site was significantly higher than on the two other sites. Greater abundance and density of shade-dependent species on all sites identified them as opportunistic replacements of gap-dependent pioneers. Pioneer species giving way to shade tolerant species is a natural process, thus make them worst variant in gap regeneration.


2018 ◽  
Vol 9 ◽  
Author(s):  
Jannigje G. Kers ◽  
Francisca C. Velkers ◽  
Egil A. J. Fischer ◽  
Gerben D. A. Hermes ◽  
J. A. Stegeman ◽  
...  

1987 ◽  
Vol 35 (2) ◽  
pp. 135 ◽  
Author(s):  
RB Hacker

Species responses to grazing and environmental factors were studied in an arid halophytic shrubland community in Western Australia. The grazing responses of major shrub species were defined by using reciprocal averaging ordination of botanical data, interpreted in conjunction with a similar ordination of soil chemical properties and measures of soil erosion derived from large-scale aerial photographs. An apparent small-scale interaction between grazing and soil salinity was also defined. Long-term grazing pressure is apparently reduced on localised areas of high salinity. Environmental factors affecting species distribution are complex and appear to include soil salinity, soil cationic balance, geomorphological variation and the influence of cryptogamic crusts on seedling establishment.


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