scholarly journals Phytophthora austrocedri in Argentina and Co-Inhabiting Phytophthoras: Roles of Anthropogenic and Abiotic Factors in Species Distribution and Diversity

Forests ◽  
2020 ◽  
Vol 11 (11) ◽  
pp. 1223
Author(s):  
María Laura Vélez ◽  
Ludmila La Manna ◽  
Manuela Tarabini ◽  
Federico Gomez ◽  
Matt Elliott ◽  
...  
Keyword(s):  
Land Use ◽  
Human Activities ◽  
Anthropogenic Impact ◽  
Anthropogenic Impacts ◽  
Abiotic Factors ◽  
Abundant Species ◽  
Phytophthora Species ◽  
Area Of Interest ◽  
Over Time

This work reports the first survey of Phytophthora diversity in the forests soils of Andean Patagonia. It also discusses the role of anthropogenic impact on Phytophthora distribution inferred from the findings on Phytophthora diversity and on the distribution of Phytophthora austrocedri-diseased forests. Invasive pathogen species threatening ecosystems and human activities contribute to their entry and spread. Information on pathogens already established, and early detection of potential invasive ones, are crucial to disease management and prevention. Phytophthora austrocedri causes the most damaging forest disease in Patagonia, affecting the endemic species Austrocedrus chilensis (D. Don) Pic. Sern. and Bizzarri. However, the relationship between anthropogenic impacts and the disease distribution has not been analyzed enough. The aims of this work were: to evaluate Phytophthora diversity in soils of Andean Patagonia using a metabarcoding method, and analyze this information in relation to soil type and land use; to assess the distribution of Austrocedrus disease over time in relation to anthropogenic and abiotic gradients in an area of interest; and to discuss the role of human activities in Phytophthora spread. High throughput Illumina sequencing was used to detect Phytophthora DNA in soil samples. The distribution of Austrocedrus disease over time was assessed by satellite imagery interpretation. Twenty-three Phytophthora species, 12 of which were new records for Argentina, were detected. The most abundant species was P. austrocedri, followed by P. × cambivora, P. ramorum and P. kernoviae. The most frequent was P. × cambivora, followed by P. austrocedri and P. ramorum. Phytophthora richness and abundance, and Austrocedrus disease distribution, were influenced by land use, anthropogenic impact and soil drainage. Results showed several Phytophthoras, including well-known pathogenic species. The threat they could present to Patagonian ecosystems and their relations to human activities are discussed. This study evidenced the need of management measures to control the spread of P. austrocedri and other invasive Phytophthora species in Patagonia.

scholarly journals Conservation of erupting ungulate populations on islands – a comment

Rangifer ◽  
2003 ◽  
Vol 23 (2) ◽  
pp. 57 ◽  
Author(s):  
Anne Gunn ◽  
Frank L. Miller ◽  
Samuel J. Barry
Keyword(s):  
Density Dependence ◽  
Rangifer Tarandus ◽  
Abiotic Factors ◽  
Environmental Variation ◽  
Juvenile Survival ◽  
Relative Importance ◽  
Subsequent Performance ◽  
Forage Availability ◽  
Over Time

A generalised model for herbivores experiencing abundant forage over time is that their numbers erupt and then decline. This model has been applied to fluctuations in caribou (Rangifer tarandus) populations especially those on islands. Since this generalised model for erupting herbivores was first proposed, two assumptions have slipped in (1) that an erupting population will crash; and (2) that the crash will be density-dependent. The problem with the assumptions is that, without testing, they can lead to inappropriate management such as culls. The first assumption arises from uncritical use of earlier accounts and the second assumption from not discriminating between the effects of environmental variation from the effects of the high herbivore numbers on forage availability (density-dependence). Often typical densitydependent effects such as lowered initial reproduction, reduced early survival of calves, and subsequent calf, yearling and juvenile survival are used to justify the contention that there are too many herbivores. But such reasoning is flawed unless cause/effect relationships are established and the role of environmental variation is evaluated. We argue that it is overly simplistic to believe that every population’s subsequent performance and fate will follow a singular pattern with only one paramount factor driving and ultimately dictating an inevitable outcome. The relative importance of unpredictable abiotic factors in influencing and causing variation in the response of ungulate populations should be investigated, no matter whether those factors are sporadic or periodic.

scholarly journals Shape of cumulative land use systems' area distribution as a parameter of anthropogenic impact on landscapes

2020 ◽  
Keyword(s):  
Land Use ◽  
Anthropogenic Impact ◽  
Anthropogenic Impacts ◽  
Cumulative Distribution ◽  
Practical Significance ◽  
Forest Steppe ◽  
Conceptual Information ◽  
General Validity ◽  
Analytical Tools ◽  
The Impact

Statement of the problem and paper objective. Current challenges address global and regional threats to biotic and landscape diversity and the urgent need for its conservation, restoration and reproduction. They make it necessary to improve the tools for conceptual, information and calculating assessment of human activities impact on the environment. That is why the study of the landscapes anthropization, i.e. the process of their transformation through human activity, and the identification of the effects of this anthropization on the environment remains the most pressing problem of geography and geoecology. Given this, the paper objective was to substantiate, develop and verify new and sufficiently informative analytical tools for modeling anthropogenic impact of the land use and/or land cover (LULC) system on landscapes and/or physic-geographic taxons. Methods and results. The experience shows that the resumptive graphic solutions for the analysis of anthropogenic impact on landscapes can be correctly represented in the form of certain modified graphs of statistics. So, the classified scheme of the LULC system areas' cumulative distribution in landscapes and/or physic-geographic taxons was substantiated and constructed as analytical tool for modeling anthropogenic impact on landscapes / taxons. The scheme is based on the concept that the types of the mentioned distribution in its shape are adequate a certain category and the intensity of anthropogenic impact on landscapes or taxons. Properly the distribution of LULC system areas was typified by the ranges for the parameter of polynomial trends in the cumulative graphs of these areas in landscapes or their aggregations. Under these conditions, the scheme of areas' cumulative distribution operates with ten types of distribution – from excessively convex to excessively concave. These types also reflect different anthropogenic impacts on taxons – from weak to excessively strong. Verification of the scheme calculating LULC system areas' cumulative distribution was realized for the test megaregion, including 30 physic-geographic areas and 130 physic-geographic districts of the five regions in the zones of mixed (coniferous / broad-leaved) and broad-leaved forests and forest-steppe of Ukraine. Relevant digital choropleths concerning anthropogenic impact on these taxons were simulated and analyzed. Scientific novelty and practical significance. Scientific novelty is determined by the reason that the developed scheme and obtained model results are more parametrically diverse than in the existing procedures. This is caused by the fact that the proposed tools are more informative and statistically effective for identification of anthropogenic impact on landscapes and physic-geographic taxons than the average-weighted and other calculating anthropization indexes or schemes for consideration the impact of only dominant LULC systems. The verification of the developed tools for the test megaregion affirmed the general validity of the proposed new methodical approaches. The paper results are applicable for the improvement of procedures, schemes and projects of environmental management for plain terrestrial landscapes and their aggregations in midlatitudes.

scholarly journals Changes of Land Use/Cover and Landscape in Zhalong Wetland as “Red-Crowned Cranes Country”, Heilongjiang Province, China

2020 ◽  
Keyword(s):  
Land Use ◽  
Landscape Pattern ◽  
Human Activities ◽  
Remote Sensing Data ◽  
Climate Trend ◽  
Zhalong Wetland ◽  
Unused Land ◽  
Landsat Satellite ◽  
Landscape Patch

<p>Hydrological and ecological role of wetlands were growing significant. Based on Landsat satellite remote sensing data collected in the years of 1990, 2000 and 2014, and integrating GIS with analytical methods of landscape ecology, research on changes of land use/cover and landscape pattern of Zhalong Wetland from 1990 to 2014 was conducted. Then, we analysed the effect of human activities and climate changes on land use/cover. The main conclusions were as follows: (1) Significant changes in land use/cover have taken place in Zhalong wetland during 1990-2014.Cultivated land, unused land and construction land increased continually, while the area of reed swamp, water swamp, grass land and water land decreased accordingly; (2) Landscape patch shape has be increasingly irregular and turned complexed, there was the tend of the growing diversification and homogenization of land use change and the growing complicate landscape pattern in Zhalong wetland; (3) There was a warm-dry climate trend from 1958 to 2014; (4) Human activities including population, construction, water land pollution and production have been threatening the wetland ecosystem. Those changes in Zhalong area were caused by nature and human activity. However, the human’s contributions are great.</p>

Pre-Columbian palaeodemography in the Atlantic Forest (Brazil): evaluating the role and influence of extreme hydroclimatic oscillations

2021 ◽  
Author(s):  
Philip Riris ◽  
Jonas Gregorio de Souza
Keyword(s):  
Land Use ◽  
South America ◽  
Atlantic Forest ◽  
Future Research ◽  
Forest Expansion ◽  
Forest Distribution ◽  
Push Factor ◽  
Over Time

&lt;p&gt;The Atlantic Forest is a major biogeographic zone of Brazil, encompassing biodiverse evergreen, semi&amp;#8208;deciduous, and&amp;#160;&lt;em&gt;Araucaria&amp;#160;&lt;/em&gt;forests. It is presently home to millions of people, and, consequently, has experienced high levels of defaunation/deforestation through fragmentation and habitat loss in recent years. A growing archaeological and palaeoecological consensus indicates growing anthropic influences on forest distribution during the pre-Columbian period, hand-in-hand with land use intensification and increasing social complexity over time.&amp;#160;&lt;/p&gt;&lt;p&gt;Against this backdrop, this paper expands upon recent palaeodemographic work in South America to evaluate the role of long-term (centennial-scale) hydroclimatic oscillations (and the antiphasing thereof) in the Atlantic Forest domain as a potential &quot;push factor&quot; engendering human-driven forest expansion. It will synthesise archaeological, palaeoclimatological, and palaeoecological records, evaluate data quality, and identify areas for expansive future research.&amp;#160;&lt;/p&gt;

scholarly journals Maximizing regional biodiversity requires a mosaic of protection levels

PLoS Biology ◽  
2021 ◽  
Vol 19 (5) ◽  
pp. e3001195
Author(s):  
Nicolas Loiseau ◽  
Wilfried Thuiller ◽  
Rick D. Stuart-Smith ◽  
Vincent Devictor ◽  
Graham J. Edgar ◽  
...  
Keyword(s):  
Protected Areas ◽  
Environmental Conditions ◽  
Human Activities ◽  
Anthropogenic Impacts ◽  
Reef Fishes ◽  
Management Tools ◽  
Unique Role ◽  
Species Numbers ◽  
Imperiled Species

Protected areas are the flagship management tools to secure biodiversity from anthropogenic impacts. However, the extent to which adjacent areas with distinct protection levels host different species numbers and compositions remains uncertain. Here, using reef fishes, European alpine plants, and North American birds, we show that the composition of species in adjacent Strictly Protected, Restricted, and Non-Protected areas is highly dissimilar, whereas the number of species is similar, after controlling for environmental conditions, sample size, and rarity. We find that between 12% and 15% of species are only recorded in Non-Protected areas, suggesting that a non-negligible part of regional biodiversity occurs where human activities are less regulated. For imperiled species, the proportion only recorded in Strictly Protected areas reaches 58% for fishes, 11% for birds, and 7% for plants, highlighting the fundamental and unique role of protected areas and their environmental conditions in biodiversity conservation.

Raza, ciencia, sociedad

2015 ◽  
Vol 2 (4) ◽  
Author(s):  
Peter Wade
Keyword(s):  
Cultural Discourse ◽  
Human Biology ◽  
Science And Society ◽  
Race Science ◽  
And Behavior ◽  
Over Time

<p class="p1"><span class="s1"><strong>Resumen </strong></span>| En este trabajo quiero presentar una cronología convencional del concepto raza que marca un movimiento en el cual raza cambia de ser una idea basada en la cultura y el medio ambiente, a ser algo biológico, inflexible y determinante, para luego volver a ser una noción que habla de la cultura<span class="s2"><strong>.</strong></span>Resumo cómo la idea de raza ha cambiado a través del tiempo, mirando necesariamente el rol que ha desempeñado la ciencia, y enfocando los diferentes discursos de índole <em>natural-cultural </em>sobre los cuerpos, el medio ambiente y el comportamiento, en los cuales las dimensiones culturales y naturales siempre coexisten<span class="s2"><strong>.</strong></span>“La naturaleza” no puede ser entendida solamente como “la biología” y ni la naturaleza ni la biología necesariamente implican sólo el determinismo, la fijeza y la inmutabilidad Estar abiertos a la coexistencia de la cultura y la naturaleza y a la mutabilidad de la naturaleza nos permite ver mejor el ámbito de acción del pensamiento racial.</p><p class="p1"><strong><em>Race, Science and Society</em></strong></p><p class="p1"> </p><p class="p2"><span class="s1"><strong>Abstract </strong></span>| In this article I present and critique a standard chronology of race as, first, a concept rooted in culture and environment, and later in human biology and determinism, and finally back to culture alone<span class="s2"><strong><em>.</em></strong></span>I will outline changing understandings of race over time, with some attention to the role of science, broadly understood, and on the continuing but changing character of race as a natural-cultural discourse about organic bodies, environments and behavior, in which both cultural and natural dimensions always co-exist<span class="s2"><strong><em>.</em></strong></span>“Nature” is not to be understood simply as “biology,” and neither nature nor biology necessarily imply the fixity and determination that they are often assumed nowadays to involve<span class="s2"><strong><em>.</em></strong></span>Being open to the co-existence of culture and nature and the mutability of the latter allows us to better comprehend the whole range of action of racial thinking.</p>

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