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Paramo is the name of the region encountered in the upper belt (3 000m - 4 800m) of the Andean mountain ridges from Venezuela to the North of Peru. Paramo ecosystem occupies only 2% of the area of those countries. Nevertheless, paramo flora is the richest high mountain flora of the world (over 3500 species, 60% of endemism). High mountain region of the Northern Andes were almost uninhabited until the arrival of the Conquistadores. At the time of the conquest, livestock and new crops were introduced to the Andean ecosystems. Since that time, paramo has been used mainly for extensive cattle grazing and cultivation of potatoes and onions. During the last three centuries an abrupt intensification of the agricultural practices has occurred. The main aim of this study is to investigate the effects of human intervention, by mean of farming, on species diversity of the paramo vegetation. The study area was selected in the paramo belt of Santurban, Colombian Eastern Cordillera. Ordination techniques were applied to analyze the relation between plant species composition, environmental variables and management variables. We found plant species diversity is influenced by cattle grazing and cropping, but the vegetation changes are mainly determined by the altitudinal gradient. Intensity of human impact is also...

There is a strong conservation need to understand traits of native species that adapt to urban environments, but results have been equivocal. Wetland birds have shown a strong phylogenetic signal towards urban tolerance; however, these species have largely been ignored in urban studies. I used Wood Storks (Mycteria americana) to determine how a wetland species of conservation concern responded to human-induced landscape change in South Florida. Specifically, my study investigated 1) resource selection of storks in roadway corridors, 2) factors influencing stork prey biomass in roadside created wetlands, 3) dietary flexibility of storks in response to human-induced landscape change, and 4) the impact of urban food subsidies on natural food limitations and stork productivity. I found that storks preferred canals and roadway corridors within the urban landscape. At a finer scale, storks selected for more natural wetland vegetation even within the urban landscape cover type. These results suggest that roadway corridors even within a highly urbanized area may provide adequate foraging habitat for storks. Factors influencing stork prey biomass in roadside created wetlands varied depending on created wetland type. I found that landscape-level vegetation and the physical properties of a created wetland were more influential in permanently inundated created wetlands whereas local-scale vegetation and hydrologic conditions were most influential in ephemeral created wetlands. Storks also selected prey that were more similar to the larger-bodied fishes in created wetlands than the smaller fishes in natural wetlands. Urban nesting storks selected prey that were more characteristic of created wetlands whereas storks nesting in natural wetlands selected prey that was more characteristic of prey found in natural wetlands. These results suggested that storks may have behavioral plasticity in foraging habitat and prey selection to adapt to some degree of human-induced rapid environmental change. Additionally, storks nesting in both urban and natural wetlands had narrow diet breadths and high productivity during optimal natural wetland conditions; however, during suboptimal natural conditions, urban stork diet expanded to include anthropogenic items, leading to increased productivity. Overall, this research provides a mechanistic understanding of how a wetland species persists, and even thrives, in an urban environment. / Includes bibliography. / Dissertation (Ph.D.)--Florida Atlantic University, 2020. / FAU Electronic Theses and Dissertations Collection

<p>The objectives of this thesis are to establish a chronological framework for environmental changes during the last 15,000 years in northwest Romania, to reconstruct the vegetation development, and to evaluate the underlying processes for forest dynamics. Furthermore, an overview of earlier and ongoing pollenstratigraphic work in Romania is provided. </p><p>Sediments from two former crater lakes, Preluca Tiganului and Steregoiu, situated in the Gutaiului Mountains, on the western extremity of the Eastern Carpathians at 730 m and 790 m a.s.l., respectively were obtained and analysed for high-resolution pollen, macrofossils, charcoal, mineral magnetic parameters and organic matter. The chronostratigraphic framework was provided by dense AMS ¹⁴C measurements. </p><p>Cold and dry climatic conditions are indicated by the occurrence of open vegetation with shrubs and herbs, and cold lake water prior to 14,700 cal. yr BP. The climatic improvement at the beginning of the Lateglacial interstadial (around 14,700 cal. yr BP) is seen by the development of open forests. These were dominated by <i>Pinus</i> and <i>Betula</i>, but contained also new arriving tree taxa, such as <i>Populus</i>, <i>Alnus</i> and <i>Prunus</i>. The gradual establishment of forests may have led to a stabilization of the soils in the catchment. Between ca. 14,100 and 13,800 cal. yr BP the forest density became reduced to stands of <i>Pinus</i>, <i>Betula</i>, <i>Alnus</i>, <i>Larix</i> and <i>Populus</i> trees and grassland expanded, suggesting colder climatic conditions. <i>Picea</i> arrived as a new taxon at around 13,800 cal. yr BP, and between 13,800 and 12,900 cal. yr BP, the surroundings of the sites were predominantly covered by <i>Picea </i>forest. This forest included <i>Betula</i>, <i>Pinus</i>, <i>Alnus</i>, <i>Larix</i> and <i>Populus</i> and, from 13,200 cal. yr BP onwards also <i>Ulmus</i>. At ca. 12,900 cal. yr BP, the forest became significantly reduced and at 12,600 cal. yr BP, a recurrence of open vegetation with stands of <i>Larix</i>, <i>Pinus</i>, <i>Betula</i>, <i>Salix</i> and <i>Alnus</i> is documented, lasting until 11,500 cal. yr BP. This distinct change in vegetation may by taken as a strong decline in temperature and moisture availability.</p><p>At the transition to the Holocene, at ca. 11,500 cal. yr BP, <i>Pinus</i>, <i>Betula</i> and <i>Larix</i> quickly expanded (from small local stands) and formed open forests, probably as a response to warmer and more humid climatic conditions. At 11,250 cal. yr BP<i> Ulmus</i> and <i>Picea</i> expanded and the landscape became completely forested. The rapid increase of <i>Ulmus</i> and <i>Picea</i> after 11,500 cal. yr BP may suggest the existence of small residual populations close to the study sites during the preceding cold interval. <i>Ulmus</i> was the first and most prominent deciduous taxa in the early Holocene in the Gutaiului Mountains. From ca. 10,750 cal. yr BP onwards <i>Quercus,</i> <i>Tilia</i>, <i>Fraxinus </i>and <i>Acer</i> expanded and <i>Corylus</i> arrived. A highly diverse, predominantly deciduous forest with <i>Ulmus</i>, <i>Quercus</i>, <i>Tilia</i>,<i> Fraxinus</i>, <i>Acer</i>, <i>Corylus</i> and <i>Picea</i> developed between 10,700 and 8200 cal. yr BP, which possibly signifies more continental climatic conditions. The development of a <i>Picea-Corylus</i> dominated forest between 8200 and 5700 cal. yr BP is likely connected to a more humid and cooler climate. The establishment of <i>Carpinus</i> and <i>Fagus</i> was dated to 5750 cal. yr BP and 5200 cal. yr BP, respectively. The dominance of <i>Fagus</i> during the late Holocene, from 4000 cal. yr BP onwards, may have been related to cooler and more humid climatic conditions. First signs of human activities are recorded around 2300 cal. yr BP, but only during the last 300 years did local human impact become significant. </p><p>The vegetation development recorded in the Gutaiului Mountains during the Lateglacial is very similar to reconstructions based on lowland sites, whereas higher elevation sites seem not to have always experienced visible vegetation changes. The time of tree arrival and expansion during the past 11,500 cal. yr BP seems to have occurred almost synchronously across Romania. The composition of the forests during the Holocene in the Gutaiului Mountains is consistent with that reconstructed at mid-elevation sites, but differs from the forest composition at higher elevations. Important differences between the Gutaiului Mountains and other studied sites in Romania are a low representation of <i>Carpinus </i>and a late and weak human impact. </p><p>The available data sets for Romania give evidence for the presence of coniferous and cold-tolerant deciduous trees before 14,700 cal. yr BP. Glacial refugia for <i>Ulmus</i> may have occurred in different parts of Romania, whereas the existence of <i>Quercu</i>s, <i>Tilia</i>, <i>Corylus</i> and <i>Fraxinus</i> has not been corroborated. </p>

The purpose of the diploma thesis is the analysis of alpine timberline shifts in the Giant Mountains between 18th and 21st century. The altitudinal position of alpine timberline is a sensitive indicator which reflects human impacts as well as the climatic changes. Methodical approach included the reconstruction of alpine timberlines from the old maps (published in 1765, 1851-52, 1879, 1906) and their comparison with the newer data, which were evaluated from a series of aerial photographs dated 1936 and 2002 (actualized 2005; data provided by supervisor). Data obtained from the old maps and aerial photographs (1936) were compared and verified with old photos and postcards from Giant Mountains. The average altitude of alpine timberline increased during the study period. The increase in elevation of alpine timberline is significant between 19th and first half of 20th century, e. g. in period when the human influence in Giant Mountains decreased. It is concluded that position of alpine timberline in Giant Mountains depended on human influence. Key words: tree line, alpine timberline, human influence, Giant Mountains

The objectives of this thesis are to establish a chronological framework for environmental changes during the last 15,000 years in northwest Romania, to reconstruct the vegetation development, and to evaluate the underlying processes for forest dynamics. Furthermore, an overview of earlier and ongoing pollenstratigraphic work in Romania is provided. Sediments from two former crater lakes, Preluca Tiganului and Steregoiu, situated in the Gutaiului Mountains, on the western extremity of the Eastern Carpathians at 730 m and 790 m a.s.l., respectively were obtained and analysed for high-resolution pollen, macrofossils, charcoal, mineral magnetic parameters and organic matter. The chronostratigraphic framework was provided by dense AMS 14C measurements. Cold and dry climatic conditions are indicated by the occurrence of open vegetation with shrubs and herbs, and cold lake water prior to 14,700 cal. yr BP. The climatic improvement at the beginning of the Lateglacial interstadial (around 14,700 cal. yr BP) is seen by the development of open forests. These were dominated by Pinus and Betula, but contained also new arriving tree taxa, such as Populus, Alnus and Prunus. The gradual establishment of forests may have led to a stabilization of the soils in the catchment. Between ca. 14,100 and 13,800 cal. yr BP the forest density became reduced to stands of Pinus, Betula, Alnus, Larix and Populus trees and grassland expanded, suggesting colder climatic conditions. Picea arrived as a new taxon at around 13,800 cal. yr BP, and between 13,800 and 12,900 cal. yr BP, the surroundings of the sites were predominantly covered by Picea forest. This forest included Betula, Pinus, Alnus, Larix and Populus and, from 13,200 cal. yr BP onwards also Ulmus. At ca. 12,900 cal. yr BP, the forest became significantly reduced and at 12,600 cal. yr BP, a recurrence of open vegetation with stands of Larix, Pinus, Betula, Salix and Alnus is documented, lasting until 11,500 cal. yr BP. This distinct change in vegetation may by taken as a strong decline in temperature and moisture availability. At the transition to the Holocene, at ca. 11,500 cal. yr BP, Pinus, Betula and Larix quickly expanded (from small local stands) and formed open forests, probably as a response to warmer and more humid climatic conditions. At 11,250 cal. yr BP Ulmus and Picea expanded and the landscape became completely forested. The rapid increase of Ulmus and Picea after 11,500 cal. yr BP may suggest the existence of small residual populations close to the study sites during the preceding cold interval. Ulmus was the first and most prominent deciduous taxa in the early Holocene in the Gutaiului Mountains. From ca. 10,750 cal. yr BP onwards Quercus, Tilia, Fraxinus and Acer expanded and Corylus arrived. A highly diverse, predominantly deciduous forest with Ulmus, Quercus, Tilia, Fraxinus, Acer, Corylus and Picea developed between 10,700 and 8200 cal. yr BP, which possibly signifies more continental climatic conditions. The development of a Picea-Corylus dominated forest between 8200 and 5700 cal. yr BP is likely connected to a more humid and cooler climate. The establishment of Carpinus and Fagus was dated to 5750 cal. yr BP and 5200 cal. yr BP, respectively. The dominance of Fagus during the late Holocene, from 4000 cal. yr BP onwards, may have been related to cooler and more humid climatic conditions. First signs of human activities are recorded around 2300 cal. yr BP, but only during the last 300 years did local human impact become significant. The vegetation development recorded in the Gutaiului Mountains during the Lateglacial is very similar to reconstructions based on lowland sites, whereas higher elevation sites seem not to have always experienced visible vegetation changes. The time of tree arrival and expansion during the past 11,500 cal. yr BP seems to have occurred almost synchronously across Romania. The composition of the forests during the Holocene in the Gutaiului Mountains is consistent with that reconstructed at mid-elevation sites, but differs from the forest composition at higher elevations. Important differences between the Gutaiului Mountains and other studied sites in Romania are a low representation of Carpinus and a late and weak human impact. The available data sets for Romania give evidence for the presence of coniferous and cold-tolerant deciduous trees before 14,700 cal. yr BP. Glacial refugia for Ulmus may have occurred in different parts of Romania, whereas the existence of Quercus, Tilia, Corylus and Fraxinus has not been corroborated.

Human disturbance as the main factor influencing the habitat of brown bear (Ursus arctos) has occurred frequently with the development of human society. How to reduce and prevent the conflict between human and brown bears is considered as an important question for brown bear conservation, management and public safety. Sånfjället National Park has one of the densest bear populations in Sweden. Many tourists are attracted to visit bears each year. Through this study, the most possibility brown bear denning habitat in Sånfjället National Park was determined by using Multi-Criteria Analysis. A customized habitat distribution map generator was programmed within the Microsoft Visual Basic® for Applications (VBA) in ArcGIS. Three themes were designed in the map generator, i.e., the human impact emphasis weighted, neutral weighted themes and customized weighted theme. Customized weighted theme was produced for user discovering denning habitat results with user-defined weights. Comparing the final maps generated from the human impact emphasis weighted and neutral weighted themes, human influence concentrated in the south area of the National Park. The trails near Sveduterget should be changed to avoid human disturbance in the bear denning period.

Abstract The grey wolf is the most widely distributed of all land mammals and is a habitat generalist that inhabits all the vegetation types of the Northern Hemisphere. Wolves also breed well and have the potential to rapidly expand to new areas. In Finland, the wolf is a game species, and as a result of Finland’s membership of the European Union, the wolf population is subject to very limited hunting due to the obligation to protect the species. Mainly for this reason, the wolf population in Finland has increased significantly in recent years. In particular, the birth rate has developed favourably and the number of litters increased from just four in 1996 to 20 in 2005. It also seems at present that the wolf population in Finland is no longer following the fluctuations in wolf numbers in Russian Karelia. The general aim of this dissertation is to provide applicable knowledge for wolf management and conservation purposes, and especially to examine the effects of human-modified landscapes on wolf population expansion in Finland. Various aspects of habitat selection were investigated in four sub-studies to gain a thorough insight into the space use and habitat needs of wolves. Species data came from a long-term wolf population study that included location information from 85 radio- and GPS-GSM-collared wolves from 1998 onwards, as well as track location data based on about 30 000 annual observations recorded with geographical coordinates by a local network of experts on large carnivores. I found that adaptability makes it possible for the wolf to live in the multiple-use, semi-wild forests of Finland and that no restrictions are imposed by the landscape on wolf population growth and expansion. In general, the results of my dissertation provide evidence that wolves tend to avoid the presence of human influence when establishing a territory and also when selecting their den site. However, as wolf numbers increase, conflict situations will more frequently occur between wolves and humans, although the risk of depredation events, for example among sheep farms, varies between farms in Finland. That is, there are some environmental and farm level factors that are associated with wolf depredation. The breeding wolf population in Finland has gradually expanded and the first litters have recently been born in western Finland after an absence of more than 100 years. The geographical distance to the Scandinavian population is shorter from these new western territories than from the population’s core area in eastern Finland. This could potentially increase the likelihood of dispersal from Finland to Scandinavia. / Tiivistelmä Susi on habitaattigeneralisti, jonka levinneisyys kattaa kaikki pohjoisen pallonpuoliskon kasvillisuustyypit. Sudet myös lisääntyvät hyvin ja voivat näin ollen levittäytyä nopeasti uusille alueille. Suomessa susi on riistalaji, jonka metsästys on rajoitettua Euroopan unionin jäsenyyden myötä. Lähinnä tästä syystä Suomen susikanta on kasvanut voimakkaasti 1990-luvun ja 2000-luvun alun aikana. Erityisesti syntyvyys on kasvanut: pentueiden määrä lisääntyi neljästä 20:een vuosien 1996 ja 2005 välillä. Näyttäisi siltä, ettei Suomen nykyinen susipopulaatio enää seuraa Venäjän Karjalassa tapahtuvia kannanvaihteluita. Väitöskirjan tavoitteena on ollut tuottaa susikannan hoidossa ja suojelussa käytettävissä olevaa tietoa ja erityisesti tutkia susikannan levittäytymistä ihmisen muokkaamassa ympäristössä Suomessa. Neljässä osatutkimuksessa on käsitelty suden habitaatinvalintaa eri näkökulmista, jotta saataisiin kokonaiskuva suden tilankäytöstä Suomessa. Tutkimusaineisto rakentui pitkäaikaisesta seuranta-aineistosta, jota on kerätty vuodesta 1989 lähtien. Vuosien 1989 ja 2010 välillä 85 sutta on pannoitettu radio- tai GPS-GSM –pannalla. Tutkimuksessa käytettiin hyväksi myös noin 30 000 vuosittain tehtyä jälkihavaintoa. Tutkimustulosten perusteella susi selviää hyvin Suomen monikäyttömetsissä, eivätkä maisematyypit itsestään rajoita susipopulaation kasvua ja levittäytymistä. Toisaalta tulokset osoittavat myös sen, että sudet välttelevät ihmistoimintoja valitessaan reviiri- tai pesäpaikkoja. Kuitenkin susien lukumäärän kasvaessa ristiriitatilanteet susien ja ihmisten välillä tulevat lisääntymään, vaikka susivahinkoriskin suuruus vaihteleekin Suomessa huomattavasti. Esimerkiksi lammastilojen susivahinkoriski riippuu sekä ympäristötekijöistä, että tilan sisäisistä tekijöistä. Kaiken kaikkiaan lisääntyvän susipopulaation esiintymisalue on Suomessa vähitellen kasvanut leviten itärajan tuntumasta kohti länttä. Tämän myötä maantieteellinen etäisyys Skandinavian susipopulaatioon on pienentynyt viimeisten vuosien aikana. Tämä voi edesauttaa susiyksilöiden siirtymistä Suomesta Skandinaviaan.

The goal of this diploma thesis: The fluence of man on increasing corporate social responsibility is describe the meaning of social responsibility and options how to increase it. Is possible to increase responsibility of corporation by employee or customer? How we can recognize that their behaviour isnť only good promotional tactic as a public relation and commercial? How government can support this behaviour and is realistic to force corporate to be morale with using the right? The result of this thesis will be find out what does it means social responsibility for normal people nowadays and what saying companies especially in Prague. Keywords Social responsibility, corporate social responsibility, ethics, individual ethics, business ethics, environment, human influence, commercial, state, law

Many regional and local factors can influence the distribution of native and exotic species in ecological communities. I examined the regional- and local-scale determinants of native and exotic vascular plant species richness and composition in a highly fragmented oak savanna ecosystem on southeastern Vancouver Island. In sharp contrast to most reported results, I found a negative relationship between native and exotic richness at the regional scale, and no relationship at the local scale. Two extrinsic factors, surrounding road density and climate, best explained the regional-scale relationship by each affecting natives and exotics in opposite ways. Road density and climate were also the dominant predictors of native and exotic composition at the regional scale. Patterns in the patch occupancy of individual species confirmed the importance of these factors but I found that low surrounding road densities and cool, wet conditions predicted the presence of many natives and the absence of many exotics. Environmental factors explained variation in richness and composition at the local scale, but these factors were different for natives and exotics. My results suggest that natives and exotics respond to roads and climate in fundamentally different ways. Roads increase both exotic propagule pressure and disturbance, which may facilitate exotic invasion. In contrast, disturbance from roads may increase the likelihood of local extinction for particular natives. Differing climatic preferences within the native and exotic species pools may also partially explain the observed patterns. There was no evidence that native diversity directly affects exotic diversity (or vice versa). Surprisingly, I found that connectivity was not an important predictor of richness or composition despite the high degree of habitat fragmentation in this ecosystem.