scholarly journals DISPERSAL POTENTIAL OF HERBACEOUS SPECIES ACCORDING TO CLIMATE, LAND USE AND HABITAT CONDITIONS IN WEST AFRICAN SAVANNAH

2017 ◽  
Vol 332 ◽  
pp. 69-87 ◽  
Author(s):  
Issouf Zerbo ◽  
Karen Hahn ◽  
Markus Bernhardt-Römermann ◽  
Oumarou Ouédraogo ◽  
Adjima Thiombiano
Keyword(s):  
Land Use ◽  
Principal Component ◽  
Climatic Conditions ◽  
West African ◽  
Herbaceous Species ◽  
Dispersal Patterns ◽  
Herbaceous Vegetation ◽  
The North ◽  
High Dispersal ◽  
Dispersal Potential

According to environmental predictions, West Africa is becoming vulnerable to the adverse effects of climate change and land use dis- turbance. Herbaceous vegetation is the most sensitive to these effects. To assess the poten- tial of species to cope with these changes, this study investigated the dispersal potential of different herbaceous species. Data on her- baceous plant composition and environmen- tal parameters were collected along climate, land use and habitat gradients in West Afri- can savannah areas, as well as the diaspores of all herbaceous species encountered. Their traits were described in order to document the diversity of diaspore categories in herbaceous savannah vegetation. Based on an occurrence diagram, variations in dissemination patterns within families were identified. The dispersal potential of each species was determined on the basis of their patterns of dispersal. A hie- rarchical classification method was used to establish a dispersal typology, and principal component analysis was applied to identify the environmental conditions that account for their patterns of dispersal. The results show that the diaspores of herbaceous spe- cies can be classified according to fruit type, diaspore type, presence of heterodiaspory, exposure of diaspores, number of seeds per diaspore, diaspore morphology, shape of diaspores and pattern of dispersal. Poaceae, the most abundant family in savannah areas, have six patterns of dispersal. Most species have more than one pattern, and species with high dispersal potential (85.43%) dominate the herbaceous vegetation. Four groups of herbaceous species were identified according to their dispersal patterns. Potentially epizoo- chorous and anemochorous species (39.25% of the flora) were more related to village areas independently of climatic conditions and habi- tat types. Potentially endozoochorous and dysozoochorous species (31.06% of the flora) were more related to fresh and dry habitats in protected areas of the North and South Suda- nian zones. Potentially hydrochorous species (12.63% of the flora) were related to wet habi- tats but were more prominent in the Sahel, and potentially autochorous species (17.06% of the flora) were more related to bowé habi- tats in the southern Sudanian zone. Our study showed that all herbaceous species have good dispersal potential, which might enable them to persist in West African savannahs despite the severe climatic changes predicted.

scholarly journals Effects of Climate and Land Use on Herbaceous Species Richness and Vegetation Composition in West African Savanna Ecosystems

2016 ◽  
Vol 2016 ◽  
pp. 1-11 ◽  
Author(s):  
Issouf Zerbo ◽  
Markus Bernhardt-Römermann ◽  
Oumarou Ouédraogo ◽  
Karen Hahn ◽  
Adjima Thiombiano
Keyword(s):  
Land Use ◽  
Species Richness ◽  
West African ◽  
Herbaceous Species ◽  
Vegetation Composition ◽  
Importance Value ◽  
African Savanna ◽  
Herbaceous Vegetation ◽  
Mixed Effect ◽  
The Impact

West African Savanna ecosystems are undergoing severe changes in their vegetation composition due to the impact of human land use and changes in climatic conditions. This study aims to examine the effect of climate, land use, and their interaction on species richness and composition of West African herbaceous vegetation. Plot based vegetation sampling was done in Burkina Faso. Specific richness and diversity indices were used to determine the effect of land use, climate, and their interaction. An importance value was computed to determine herbaceous species dominating the communities. Frequency of species is used to examine their distribution pattern. The results showed that climate significantly influenced herbaceous specific richness more than land use. However, land use had a significant effect on herbaceous vegetation composition. Herbaceous species diversity changed with environmental conditions. The floristic composition of dominant species is driven by both climate and land use. The frequency of distribution demonstrated that herbaceous species occurrences were more influenced by the mixed effect of climate and land use than their separate effects. Occasional and rare species are the most important part of herbaceous vegetation. Thus heterogeneity of Savanna ecosystem and vulnerability of herbaceous species are high.

scholarly journals A Perspective on Inhabited Urban Space: Land Use and Occupation, Heat Islands, and Precarious Urbanization as Determinants of Territorial Receptivity to Dengue in the City of Rio De Janeiro

2020 ◽  
Vol 17 (18) ◽  
pp. 6537
Author(s):  
Jefferson Pereira Caldas Santos ◽  
Nildimar Alves Honório ◽  
Christovam Barcellos ◽  
Aline Araújo Nobre
Keyword(s):  
Land Use ◽  
Urban Space ◽  
Urban Sprawl ◽  
Rio De Janeiro ◽  
Principal Component ◽  
Map Algebra ◽  
Heat Islands ◽  
Environmental Processes ◽  
The North ◽  
The City

Introduction: Rio de Janeiro is the second-largest city in Brazil, with strong socio-spatial segregation, and diverse and heterogeneous land use, occupation, and landscapes. The complexity of dengue requires the construction of surveillance and control tools that take into account the historical, social, economic, and environmental processes mediated in the territory as a central axis of public policy. In this context, this study aimed to stratify the city into areas of receptivity to dengue, using innovative “territorial indicators” because they are built based on the actual occupation of the territory. Methods: We designed and constructed 17 indicators that sought to characterize the transformed and inhabited space according to receptivity to dengue. We used data on land use and occupation, connectivity, climate, and landscape. We developed the dengue receptivity through principal component analysis (PCA), using multiple criteria analysis and map algebra integrated in a GIS platform. Results: The most receptive areas were concentrated in the transition between the north and west zones of the city, a region of unconsolidated urban sprawl. The areas of greatest receptivity had the highest incidence and density of Aedes eggs during the study period. The correlation between receptivity index and incidence rate was positive in the epidemic years. Conclusion: The proposed set of indicators was able to identify areas of greater receptivity, such as regions of disorderly urban sprawl, with a concentration of social and environmental processes that are related to the occurrence of dengue outbreaks and high vector density. On the other hand, population immunity plays an important role in the spatial distribution of dengue during non-epidemic years.

Linking indices of biotic integrity to environmental and land use variables: multimetric clustering and predictive models

2009 ◽  
Vol 59 (1) ◽  
pp. 1-8 ◽  
Author(s):  
Vladimir Novotny ◽  
David Bedoya ◽  
Hardik Virani ◽  
Elias Manolakos
Keyword(s):  
Land Use ◽  
Fish Community ◽  
Principal Component ◽  
Component Analysis ◽  
Stream Habitat ◽  
State Agencies ◽  
Data Bases ◽  
North Central ◽  
The North ◽  
Analyze Data

Advanced computerized methods and models of retrieving knowledge from large multiparameter data bases were used to analyze data on fish and macroinvertebrate composition (metrics), habitat, land use and water quality. The research focused on the north central and northeastern United States and involved thousands of sites monitored by the state agencies. The techniques and methodologies included supervised and unsupervised Artificial Neural Networks (ANN) modeling, Principal Component Analysis, Canonical Component Analysis (both linear and nonlinear), Multiple Regression Analyses, and analyses of variance by ANOVA. The research resulted in defining a concept of clusters of sites based on their biotic (fish) community composition, identified cluster dominating factors, and developed meaningful models for predicting fish composition based on environmental and in—stream habitat stresses.

Use of principal component analysis for identification of Rockland and Trego Hot Springs tephras in the Hat Creek Graben, northeastern California, USA

2014 ◽  
Vol 81 (1) ◽  
pp. 125-137 ◽  
Author(s):  
Solène Pouget ◽  
Marcus Bursik ◽  
Joaquín A. Cortés ◽  
Chris Hayward
Keyword(s):  
Principal Component Analysis ◽  
Hot Springs ◽  
Prediction Interval ◽  
Principal Component ◽  
Component Analysis ◽  
Similarity Coefficients ◽  
Dispersal Patterns ◽  
The North ◽  
New Findings ◽  
Tephra Layers

AbstractDiscontinuous tephra layers were discovered at Burney Spring Mountain, northern California. Stratigraphic relationships suggest that they are two distinct tephras. Binary plots and standard similarity coefficients of electron probe microanalysis data have been supplemented with principal component analysis to correlate the two tephra layers to known regional tephras. Using principal component analysis, we are furthermore able to bound our uncertainty in the correlation of the two tephra layers. After removal of outliers, within the 95% prediction interval, we can say that one tephra layer is likely the Rockland tephra, aged 565–610 ka, and the second layer is likely from Mt. Mazama, the Trego Hot Springs tephra, aged ~ 29 ka. In the case of the Rockland tephra, the new findings suggest that dispersal to the north was highly restricted. For Trego Hot Springs ash, the new findings extend the distribution to the southwest, with a rapid thinning in that direction. Coupled with considerations of regular tephra dispersal patterns, the results suggest that the primary dispersal direction for both tephras was to the south, and that occurrences in other directions are unlikely or otherwise anomalous.

Peculiarities of the course of the postpartum period in domestic reindeer females, its morphophysiology and behavioral reactions in the North-East of Russia (Republic of Sakha)

2020 ◽  
pp. 99-105
Author(s):  
V. Fedorov ◽  
E. Sleptsov ◽  
K. Plemyashov
Keyword(s):  
Postpartum Period ◽  
Reproductive Function ◽  
Complex Problem ◽  
Climatic Conditions ◽  
Taiga Zone ◽  
Behavioral Reactions ◽  
North East ◽  
The North ◽  
The Republic ◽  
Mountain Taiga

A growth in the number of deer and an increase in their productivity are closely related to the solution of the complex problem of reproduction and rational use of deer females. Significant damage to reindeer husbandry is caused by the barrenness of northern domestic deer, the level of which has been quite high in recent years. So, in the Republic of Sakha, on 01.01.2020, the number of domesticated reindeer was 152,068, of which female deer and heifers — 71,818, offspring per 100 females — 59, business yield amounted to 52 fawns per 100 females. The causes of infertility are very diverse, as the natural and climatic conditions of the breeding zones have a significant influence on the reproductive function of reindeer. In Yakutia, the main population of northern domestic deer is bred in mountain taiga and tundra natural-climatic zones, so there are about 55 thousand deer in the mountain taiga zone and more than 65 thousand deer in the tundra zone. In this regard, the study of the peculiarities of the postpartum period course in domestic reindeer females, its morphophysiology, and behavioral reactions depending on the natural and climatic conditions of breeding is of great importance.

ЗУБРЫ НА СЕВЕРЕ РОССИИ — НАСТОЯЩЕЕ И БУДУЩЕЕ

2019 ◽  
pp. 42-44
Author(s):  
I.V. GUSAROV ◽  
V.A. OSTAPENKO ◽  
T.V. NOVIKOVА
Keyword(s):  
Biological Diversity ◽  
Climatic Conditions ◽  
Economic Consequences ◽  
European Bison ◽  
Rare And Endangered Species ◽  
The North ◽  
Rare And Endangered ◽  
Relationship Of ◽  
First Time ◽  
The Relationship

Впервые в мире создана популяция зубров на территории 60 градусов северной широты. В новых климатических условиях разведения и сохранения зубров определены и проанализированы факторы существования вида на севере Европейской части РФ. Выявлены признаки, динамика численности, которые являются составной частью системы, предназначенной для управления биоразнообразием. Интродукция, являясь процессом введения в экосистему нехарактерных для нее видов, может усиливать изменения биоценозов как положительно, так и отрицательно. Насколько быстро и успешно проходит процесс адаптации заселенного вида, и усматривается его влияние на окружающую среду зависит дальнейшее существование зубров и в целом биоразнообразия. В статье обсуждаются вопросы взаимоотношения зубров с другими видами копытных и хозяйственной деятельностью человека, а также дальнейшим использованием зубров в сельскохозяйственном производстве. Пластичность зубров, выявление изменений и их анализ при вселении видов в новые условия обитания необходимы не только для определения развития или деградации биоценозов и в целом экосистемы, но и прогноза социально-экономических последствий интродукции как одного из методов сохранения редких и исчезающих видов фауны.For the first time in the world, a bison population has been created in an area of 60 degrees north latitude. In the new climatic conditions of breeding and preservation of bison, the factors of the species existence in the north of the European part of the Russian Federation are identified and analyzed. The signs, dynamics of abundance, which are an integral part of the system designed to manage biodiversity are identified, since the preservation of biological diversity on the planet is one of the main problems of our time. Introduction, being the process of introducing non-typical species into an ecosystem, can enhance changes in biocenoses, both positively and negatively. The question posing sounds especially when it comes to such a large hoofed animal as the European bison. How quickly and successfully the process of adaptation of the universe takes place and its environmental impact is seen depends on the continued existence of bison and biodiversity in general. The article discusses the relationship of bison with other types of ungulates and human activities, as well as the further use of bison in agricultural production. How these issues will be resolved positively depends on the future of these animals. Thus, the plasticity of bison, the identification of changes and their analysis, with the introduction of species into new habitat conditions is necessary not only to determine the development or degradation of biocenoses and the ecosystem as a whole, but also to predict the socio-economic consequences due to the introduction as one of the methods of preserving rare and endangered species of fauna.

scholarly journals Radial Growth Response of European Larch Provenances to Interannual Climate Variation in Poland

Forests ◽  
2021 ◽  
Vol 12 (3) ◽  
pp. 334
Author(s):  
Norbert Szymański ◽  
Sławomir Wilczyński
Keyword(s):  
Radial Growth ◽  
Climatic Factors ◽  
Principal Component ◽  
Climatic Conditions ◽  
Growth Responses ◽  
European Larch ◽  
Temperature And Precipitation ◽  
Provenance Trials ◽  
High Precipitation ◽  
Climatic Elements

The present study identified the similarities and differences in the radial growth responses of 20 provenances of 51-year-old European larch (Larix decidua Mill.) trees from Poland to the climatic conditions at three provenance trials situated in the Polish lowlands (Siemianice), uplands (Bliżyn) and mountains (Krynica). A chronology of radial growth indices was developed for each of 60 European larch populations, which highlighted the interannual variations in the climate-mediated radial growth of their trees. With the aid of principal component, correlation and multiple regression analysis, supra-regional climatic elements were identified to which all the larch provenances reacted similarly at all three provenance trials. They increased the radial growth in years with a short, warm and precipitation-rich winter; a cool and humid summer and when high precipitation in late autumn of the previous year was noted. Moreover, other climatic elements were identified to which two groups of the larch provenances reacted differently at each provenance trial. In the lowland climate, the provenances reacted differently to temperature in November to December of the previous year and July and to precipitation in September. In the upland climate, the provenances differed in growth sensitivity to precipitation in October of the previous year and June–September. In the mountain climate, the provenances responded differently to temperature and precipitation in September of the previous year and to precipitation in February, June and September of the year of tree ring formation. The results imply that both climatic factors and origin (genotype), i.e., the genetic factor, mediate the climate–growth relationships of larch provenances.

scholarly journals Agriculture and land use in the North of Russia: Case study of Karelia and Yakutia

2020 ◽  
Vol 12 (1) ◽  
pp. 1497-1511
Author(s):  
Alexey Naumov ◽  
Varvara Akimova ◽  
Daria Sidorova ◽  
Mikhail Topnikov
Keyword(s):  
Land Use ◽  
Agricultural Development ◽  
Agricultural Land ◽  
Geographical Location ◽  
Special Role ◽  
Sources Of Information ◽  
Local Conditions ◽  
Climate Conditions ◽  
The North ◽  
The Republic

AbstractDespite harsh climate, agriculture on the northern margins of Russia still remains the backbone of food security. Historically, in both regions studied in this article – the Republic of Karelia and the Republic of Sakha (Yakutia) – agricultural activities as dairy farming and even cropping were well adapted to local conditions including traditional activities such as horse breeding typical for Yakutia. Using three different sources of information – official statistics, expert interviews, and field observations – allowed us to draw a conclusion that there are both similarities and differences in agricultural development and land use of these two studied regions. The differences arise from agro-climate conditions, settlement history, specialization, and spatial pattern of economy. In both regions, farming is concentrated within the areas with most suitable natural conditions. Yet, even there, agricultural land use is shrinking, especially in Karelia. Both regions are prone to being affected by seasonality, but vary in the degree of its influence. Geographical location plays special role, and weaknesses caused by remoteness to some extent become advantage as in Yakutia. Proximity effect is controversial. In Karelia, impact of neighboring Finland is insignificant compared with the nearby second Russian city – Saint Petersburg.

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