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  • About
  • The Global ETD Search service is a free service for researchers to find electronic theses and dissertations. This service is provided by the Networked Digital Library of Theses and Dissertations.
    Our metadata is collected from universities around the world. If you manage a university/consortium/country archive and want to be added, details can be found on the NDLTD website.
1

An Assessment of Trampling Impact on Alpine Vegetation, Fiordland and Mount Aspiring National Parks, New Zealand

Squires, Carolyn January 2007 (has links)
The objectives of this study were two fold. The first was to quantify the nature and extent of current levels of human impact in alpine areas at four sites within Fiordland and Mount Aspiring National Parks along walking tracks at Key Summit, Gertrude Saddle, Borland Saddle and Sugarloaf Pass. In order to do so, a survey was carried out with transects placed perpendicular to the track, and distributed among different vegetation types. In each transect, plant structural and compositional aspects, and soil and environmental parameters were measured. Transects were divided into track, transition, undisturbed and control zones, and changes to dependent variables were compared with distance from the track centre. Damage from visitor impact was largely restricted to within 1m from the track centre. The most significant impacts were to structural aspects of plant and soil properties with significant reductions in plant height, total vegetation cover and bryophyte cover, and increases in bareground and erosion on tracks. Erosion was more prevalent on slopes greater than 25°, while tracks on peat soils contained greater bareground exposure, particularly of organic soil. The second study objective was to investigate the relationship between specific levels of impact and the resulting damage to two key alpine vegetation types, tussock herb field and cushion bog. This was undertaken by carrying out controlled trampling experiments, measuring changes to plant structural and compositional aspects four weeks and one year after treatment. Both vegetation types saw dramatic reductions in total vegetation cover and height immediately after trampling, however overall composition and species richness varied little. These two alpine vegetation types showed moderate-low resistance to initial impact and low resilience, with very little recovery evident one year later. Research intothese two areas is important for managing visitor use within alpine areas in order to meet conservation and recreation goals. The survey indicates that alpine community types are very sensitive to visitor use, showing significant structural damage, however the spatial extent of impact is limited within the broader landscape. Instead, visitor impacts associated with tracks are likely to be more visually and aesthetically significant, influencing the visitor experience. The trampling experiments indicate that use levels over 25-75 passes per year within tussock herbfield and cushion bog vegetation on peat soils will result in ongoing damage to previously undisturbed sites. Methods for minimising impacts include limiting visitor numbers, public education in low impact practices, redirection of tracks and use to areas that are less sensitive, the dispersal of visitor activity at very low use intensities (less than 75 direct passes per year) and the concentration of activity on tracks above this level.
2

An Assessment of Trampling Impact on Alpine Vegetation, Fiordland and Mount Aspiring National Parks, New Zealand

Squires, Carolyn January 2007 (has links)
The objectives of this study were two fold. The first was to quantify the nature and extent of current levels of human impact in alpine areas at four sites within Fiordland and Mount Aspiring National Parks along walking tracks at Key Summit, Gertrude Saddle, Borland Saddle and Sugarloaf Pass. In order to do so, a survey was carried out with transects placed perpendicular to the track, and distributed among different vegetation types. In each transect, plant structural and compositional aspects, and soil and environmental parameters were measured. Transects were divided into track, transition, undisturbed and control zones, and changes to dependent variables were compared with distance from the track centre. Damage from visitor impact was largely restricted to within 1m from the track centre. The most significant impacts were to structural aspects of plant and soil properties with significant reductions in plant height, total vegetation cover and bryophyte cover, and increases in bareground and erosion on tracks. Erosion was more prevalent on slopes greater than 25°, while tracks on peat soils contained greater bareground exposure, particularly of organic soil. The second study objective was to investigate the relationship between specific levels of impact and the resulting damage to two key alpine vegetation types, tussock herb field and cushion bog. This was undertaken by carrying out controlled trampling experiments, measuring changes to plant structural and compositional aspects four weeks and one year after treatment. Both vegetation types saw dramatic reductions in total vegetation cover and height immediately after trampling, however overall composition and species richness varied little. These two alpine vegetation types showed moderate-low resistance to initial impact and low resilience, with very little recovery evident one year later. Research intothese two areas is important for managing visitor use within alpine areas in order to meet conservation and recreation goals. The survey indicates that alpine community types are very sensitive to visitor use, showing significant structural damage, however the spatial extent of impact is limited within the broader landscape. Instead, visitor impacts associated with tracks are likely to be more visually and aesthetically significant, influencing the visitor experience. The trampling experiments indicate that use levels over 25-75 passes per year within tussock herbfield and cushion bog vegetation on peat soils will result in ongoing damage to previously undisturbed sites. Methods for minimising impacts include limiting visitor numbers, public education in low impact practices, redirection of tracks and use to areas that are less sensitive, the dispersal of visitor activity at very low use intensities (less than 75 direct passes per year) and the concentration of activity on tracks above this level.
3

Long-term vegetation monitoring – a 33 year record from table mountain

Emms, Paul Ivor January 2013 (has links)
Magister Scientiae (Biodiversity and Conservation Biology) / Nearly 40 years ago McLachlan and Moll highlighted the need for a well-defined path system on the Western Table of Table Mountain in the immediate vicinity of the Upper Cable Station (UCS). At that time the numbers of people using the cableway was heavily impacting the vegetation on the Western Table, particularly in the vicinity of the UCS. This prompted a study by Coley (1977) to assess the long-term impacts of trampling in this area. In order to monitor changes in the vegetation through time Coley set up 12 permanently marked plots (each ~4x4 m), arranged at increasing distances from the UCS. Plot positions were carefully selected so that the effects of trampling on the vegetation could be measured at various points (distance being a surrogate for trampling intensity). Field observations in 1977 revealed that Mountain Fynbos vegetation was heavily impacted by cableway tourists. Furthermore the vegetation was most damaged closest to the UCS, with a sharp decrease in damage with increasing distance from the station. In order to monitor the vegetation change Coley used aerial photographs of permanently marked plots, so that visual comparisons of species cover, condition and composition could be made over time. The vegetation was then assessed in terms of percentage cover, and percentage damaged for each plot. My study marks the fifth time data were collected since Coley (1977) and the results show that there has been a marked improvement in vegetation quality since the construction of well-defined paths and a concerted effort by managers to ensure tourists do not leave the paths; which has greatly reduced trampling since the 1997 upgrade. The implications of this study provided evidence of the importance of restricting iv tourist traffic in areas that are regularly visited and, therefore, highly impacted. It also shows that denuded fynbos is resilient and does recover over time, provided that the substrate is not eroded too heavily by trampling. Finally, I present several management recommendations, of which the most controversial, albeit important, is for a rotational block burn programme on the Western Table; since fire is a keystone ecological process that has been absent of the Western Table for at least 80 to 90 years.
4

An Analysis of Human Disturbance to Rocky Intertidal Communities of San Luis Obispo County

Waltz, Grant Tyler 01 December 2012 (has links)
ABSTRACT An Analysis Of Human Disturbance To Rocky Intertidal Communities Of San Luis Obispo County Grant Tyler Waltz The number of coastal areas open to public access in California and San Luis Obispo County is increasing due to the acquisition by California State Parks of land previously owned by private entities. For example, California State Parks acquired property from the Hearst Corporation in 2005, which included 18 miles of coastline. California State Parks is responsible for providing public access in these newly acquired areas and also for maintaining the health of the natural systems found on these properties. Part of the California State Parks’ strategic vision maintains that they seek to consider the impacts of every decision they make on the next seven generations of Californians. To balance the competing demand of providing access with long-term sustainability, State Parks managers require sound scientific data to evaluate the impacts of human access to the ecosystems they manage. One ecosystem susceptible to human access in these new State Park areas and in other areas throughout the state is the rocky intertidal (e.g. Beauchamp and Gowing 1982, Ghazanshahi et al. 1983, Hockey and Bosman 1986, Povey and Keough 1991, Addessi 1994, Fletcher and Frid 1996, Brown and Taylor 1999, Murray et al. 1999, Van De Werfhorst and Pearse 2007). This thesis represents a collaborative effort between State Parks Managers scientists at California Polytechnic State University San Luis Obispo, and scientists at Tenera Environmental Inc. to provide sound scientific data on the impacts of visitors to rocky intertidal biological communities in San Luis Obispo County. A three-pronged approach was used to assess the effect of visitors to rocky intertidal communities: 1) an observational study to quantify visitor densities in publicly accessible rocky intertidal communities, 2) an experimental manipulation of visitor density to rocky intertidal communities based on the visitor densities observed in part 1 and used to identify organisms susceptible to foot traffic (access-indicator taxa), and 3) an observational study of publicly accessible rocky intertidal sites exposed to levels of foot traffic shown to cause declines in access-indicator taxa from part 2. I was involved with all three portions of the study and my thesis is focused on presenting and discussing parts 1 and 3 in detail. Visitor counts and the observational access-indicator taxa study (parts 1 and 3) were conducted in Montaña de Oro State Park (MDO) in San Luis Obispo County from 2007-2009. There was abundant accessible rocky intertidal coastline in the park. Three popular rocky intertidal sites were chosen within the park to conduct visitor counts. Visitors were quantified from fixed locations on the bluff above each of the three observation sites on sixteen occasions during the course of three years. These counts were used to estimate the annual number of visitors to each site. The area of each intertidal observation site was also calculated and with the annual number of visitors, was used to calculate the annual density of visitors to the rocky intertidal at each site. This represents a novel approach to quantifying visitor numbers to rocky intertidal communities. Additionally, I examined whether there was a relationship between the number of cars entering the park and the density of rocky intertidal visitors or between the number of cars parked at each site and the density of rocky intertidal visitors. The annual density of visitors at one of the observation sites in MDO, Hazard Reef, was shown to be approximately equal to the moderate treatment level from the experimental study (part 2). This moderate level of visitor density was shown to significantly reduce the abundance of five rocky intertidal taxa: rockweed (Silvetia compressa, Hesperophycus californicus, and Fucus gardneri), Endocladia muricata, Mastocarpus papillatus, limpets, and chitons. To assess whether long-term exposure to foot traffic could impact the abundance of access-indicator taxa in MDO, the abundance of these taxa was sampled at Hazard Reef and compared to the abundance of the same taxa at two adjacent sites with much lower annual densities of visitors. A stratified random sampling design was used to assess the abundance of the five access-indicator taxa found in the mid-intertidal zone at these three sites in the spring of 2009. My work demonstrated that visitor densities and patterns of use were variable among the three accessed intertidal sites in MDO. Annual visitor numbers to the rocky intertidal for the three observation sites within MDO were between 3,000-5,000 people. There was no relationship between the number of cars entering the park and the annual density of visitors to the rocky intertidal. The number of parked cars was significantly related to visitor density at one study site suggesting that under specific circumstances, controlling parking lot size may be a viable approach to managing impacts to intertidal areas. Significant differences in limpet density (60 per m2) were detected in a moderately accessed intertidal site relative to adjacent and less visited sites. The abundance of combined algae and limpets were lower at the moderate use site when the lower use sites were compared together against it. Patterns of rocky intertidal habitat use and the estimated annual visitor density suggest that some areas in San Luis Obispo County may be exposed to damaging levels of visitors. The current study identified that the abundance of one out of five experimentally identified access-indicator taxa (Rockweed, Mastocarpus papillatus, Endocladia muricata, Limpets, and Chitons) had been significantly reduced at a popular rocky intertidal site, relative to adjacent and less visited sites.
5

Úloha ochozů volně žijících kopytníků ve vegetaci teplomilných trávníků / The role of trampling trails of wild ungulates in the vegetation of semi dry grasslands

Vacková, Nikol January 2015 (has links)
Animals affect vegetation in many different ways. In this thesis we have focused on the impact of wild ungulates in the Czech Republic (wild boar, red deer, sika deer, roe deer). These animals affect vegetation with grazing, defoliation, defecation, browsing and other activities. We decided to study the effect of browsing. The animal trails are formed by browsing animals. These trails can be easily recognized due to long-term browsing. They are especially caused by trampling, which affects vegetation in many ways. The aim of this study is to determine how the vegetation of dry-grasslands (Festuco-Brometea) responds to long-term trampling caused by wild ungulates. We found that on trails, there is more bare soil, less litter and lower vegetation. In its close proximity, there is also a slightly greater diversity of plants than in control samples. Species like Plantago media which are growing straight on the trail, have adapted to trampling, while smaller shrubs (eg. Rubus, Crataegus), start to appear 2 meters from the trail. Using Ellenberg values, we found out that heliophile species, which grow on the trails and the species in control samples need more moisture and more nitrogen. Using the experiment with transplanted blocks, we learned how vegetation responds to the introduction/exclusion of...
6

Análise da microbiota simbionte do zoantídeo Palythoa caribaeorum (Duchassaing e Michelotti, 1860) na Praia de Porto de Galinhas - PE

BORGES, Sawana Caroline de Aquino 26 February 2014 (has links)
Submitted by Caroline Falcao (caroline.rfalcao@ufpe.br) on 2017-05-25T16:17:50Z No. of bitstreams: 2 license_rdf: 811 bytes, checksum: e39d27027a6cc9cb039ad269a5db8e34 (MD5) DISSERTAÇÃO FINAL SAWANA BORGES.pdf: 1343555 bytes, checksum: 626a5657eff4bd97ecd102c75073d331 (MD5) / Made available in DSpace on 2017-05-25T16:17:50Z (GMT). No. of bitstreams: 2 license_rdf: 811 bytes, checksum: e39d27027a6cc9cb039ad269a5db8e34 (MD5) DISSERTAÇÃO FINAL SAWANA BORGES.pdf: 1343555 bytes, checksum: 626a5657eff4bd97ecd102c75073d331 (MD5) Previous issue date: 2014-02-26 / As áreas recifais que se utilizam do turismo são susceptíveis às mudanças em sua fauna e flora como impactos negativos. Alguns cnidários são importantes bioindicadores de alterações físico-químicas no ecossistema. Devido a isso, foi realizada a análise da microbiota simbionte do zoantídeo Palythoa caribaeorum na Praia de Porto de Galinhas (PE) para avaliação da influência temporal e do pisoteio nesse organismo. As amostras foram coletadas mensalmente no período de junho a dezembro do ano de 2012, em áreas com pisoteio e sem pisoteio. Foram analisadas as variáveis de densidade populacional, índice mitótico, diâmetro celular e clorofilas a e c das zooxantelas e altura, quantidade e volume dos pólipos de P. caribaoerum associadas com alguns parâmetros abióticos (pluviosidade, temperatura, salinidade, pH e nutrientes). Foi observada variação significativa do índice mitótico, com maior média no período chuvoso (9.38 ± 0.62%) e diâmetro celular, com maior média no período de estiagem (11.30 ± 0.91μm). A pluviosidade, a salinidade, o pH, o fosfato e o silicato exerceram uma influência significativa no índice mitótico e no diâmetro celular das zooxantelas. O volume dos pólipos apresentou diferença significativa temporal, com maiores valores no período chuvoso e também influenciou no índice mitótico e no diâmetro celular desses simbiontes. A clorofila a variou de forma significativa entre os dois períodos estudados, apresentando maiores valores no período chuvoso. A biomassa clorofiliana (clorofilas a e c) foi influenciada pela pluviosidade, salinidade, volume dos pólipos e pelos sais nutrientes nitrito, fosfato e silicato. O pisoteio dos banhistas sobre os recifes não demonstrou influência sobre as variáveis estudadas, apesar do escossistema recifal sofrer intensa atividade turística. O zoantídeo P. caribaoerum indicou uma forte adaptação aos estresses ambientais, apresentando métodos para compensar a influência da variação dos fatores abióticos, não sofrendo intervenções na capacidade fotossintética dos seus simbiontes. / The reef areas that use tourism are susceptible to changes in flora and fauna as negative impacts. Some cnidarians are important bioindicators of physicochemical changes in the ecosystem. Because of this, analysis of the symbiotic microbiota zoanthid Palythoa caribaeorum in Porto de Galinhas Beach (PE) to assess the temporal influence and trampling were applied in this organism. Samples were collected monthly from June to December of the year 2012, in areas with and without trampling. The variables of population density, mitotic index, cell diameter and chlorophyll a and c of zooxanthellae and height, number and volume of polyps were analyzed for P. caribaoerum associated with some abiotic parameters (rainfall, temperature, salinity, pH, and nutrients). Significant variation in mitotic index was observed, with the highest average in the rainy season (9.38 ± 0.62%) and cell diameter, with the highest average in the dry season (30.11 ± 0.91μm). Rainfall, salinity, pH, phosphate and silicate exerted a significant influence on the mitotic index and the cell diameter of the zooxanthellae. The volume of polyps showed significant temporal differences, with higher values in the rainy season and also influenced the mitotic index and the cell diameter of these symbionts. The chlorophyll a was significantly different between the two study periods, with higher values in the rainy season. The chlorophyllian biomass (chlorophyll a and c) was influenced by rainfall, salinity, volume of polyps and the nutrient salts nitrite, phosphate and silicate. The trampling of bathers on the reefs showed no influence on these variables, although the reef escossistem suffer intense tourist activity. The zoanthid P. caribaoerum indicated a strong adaptation to environmental stresses, presenting methods to compensate the influence of the variation of abiotic factors, not suffering interventions in the photosynthetic capacity of their symbionts.
7

Impacto de animais sobre a vegetação herbácea em um banhado subtropical no extremo sul do Brasil

Hosncha, Letícia Coutelle January 2014 (has links)
Submitted by Anaclaudia Mattos Villalba (anaclaudiamattosvillalba@gmail.com) on 2016-04-09T21:15:00Z No. of bitstreams: 1 youblisher.com-1122729-Disserta_o_Leticia_Coutelle_Honscha.pdf: 1337135 bytes, checksum: e79f26e358538e0daa5b930418bd10ba (MD5) / Approved for entry into archive by cleuza maria medina dos santos (cleuzamai@yahoo.com.br) on 2016-05-05T21:07:39Z (GMT) No. of bitstreams: 1 youblisher.com-1122729-Disserta_o_Leticia_Coutelle_Honscha.pdf: 1337135 bytes, checksum: e79f26e358538e0daa5b930418bd10ba (MD5) / Made available in DSpace on 2016-05-05T21:07:39Z (GMT). No. of bitstreams: 1 youblisher.com-1122729-Disserta_o_Leticia_Coutelle_Honscha.pdf: 1337135 bytes, checksum: e79f26e358538e0daa5b930418bd10ba (MD5) Previous issue date: 2014 / A sazonalidade climática exerce forte influência sobre as espécies herbáceas, podendo modificar a estrutura da sua comunidade. A ação de animais, tais como a herbivoria, o pisoteio e o desenraizamento das plantas também exercem pressão sobre a comunidade vegetal. No extremo sul do Brasil, encontra-se o Banhado do Taim, uma área rica na biodiversidade de fauna e flora, onde foi implementada uma área de preservação ambiental, a Estação Ecológica do Taim. O presente estudo teve como objetivo avaliar o impacto que os animais causam na vegetação herbácea do Banhado do Taim. Foram feitos os levantamentos florístico e fitossociológico, a fim de descrever a riqueza da vegetação da área a ser estudada. Para avaliar o impacto da presença de animais sobre a vegetação herbácea do banhado, foi montado um experimento, utilizando a metodologia de parcelas de exclusão de animais. Esta metodologia consiste em comparar o crescimento de plantas presentes em uma parcela aberta com o crescimento das plantas em uma parcela de exclusão, onde os animais não tem acesso a vegetação. Para analisar os dados, utilizamos o teste de ANOSIM para comparar a diferença entre os tratamentos nas parcelas abertas (tratamento aberto) e fechadas (tratamento de exclusão). A seguir aplicamos e teste t de Student para comparar a frequência de ocorrência e o crescimento de cada espécie entre os tratamentos (aberto e exclusão). Um novo teste t de Student foi aplicado para avaliar o crescimento sazonal das espécies, nos tratamentos aberto e exclusão, agrupando os dados por estações frias e quentes. O levantamento florístico registrou 119 espécies, sendo 77 registradas na fitossociologia e 33 na metodologia de parcelas de exclusão. As espécies Achyrocline satureioides (Lam) DC., Cyperus esculentus L., Cyperus surinamensis Rottb., Ipomoea cairica (L.) R.Br., Kyllinga vaginata Lam. e Sesbania cf. brasiliensis (Cav.) Burkart apresentaram diferenças significativas (p<0,05) em sua frequência de ocorrência, entre os tratamentos aberto e de exclusão. Enquanto que C. esculentus, C. surinamensis, Ischaemum minus J. Pers., K. vaginata., Paspalum distichum L., S. cf. brasiliensis, Solidago chilensis Meyen e Tibouchina sp. Aubl. diferiram significativamente (p<0,05) em seu crescimento, também entre os tratamentos aberto e de exclusão. Nas estações frias as espécies Canna glauca L., Solanum americanum Mill. e S. chilensis apresentaram seu crescimento com diferenças significativas (p<0,05) entre o outono e o inverno, enquanto que S. chilensis e Tibouchina sp. diferiram seu crescimento significativamente (p<0,05) nas estações quentes, entre primavera e verão. Verificamos que a cobertura da comunidade de plantas, se mantém estável ao longo do ano, porém quando focamos em cada espécie separadamente, percebemos que algumas delas diferem na sua frequência de ocorrência e/ou em seu crescimento. Sendo assim, podemos dizer que o Banhado do Taim possui uma dinâmica funcional, o qual consegue manter seus padrões ecologicamente equilibrados. / The climatic seasonality exerts strong influence on herbaceous species, and may modify the structure of their community. The action of animals such as grazing, trampling and uprooting plants also exert pressure on the plant community. The Taim wetland, in southern Brazil, is an area rich in biodiversity of flora and fauna, where an area of environmental preservation was implemented: the Taim Ecological Station. The present study aimed to evaluate the impact that large animals cause on the herbaceous Taim wetland. The floristic surveys and phytosociological were made in order to describe the richness of the vegetation of the area being studied. To assess the impact of the presence of animals on the herbaceous vegetation of the wetland, an experiment was set up using the cage methodology of exclusion animals. This methodology is to compare the growth of plants present in an open plot with growing plants in a plot of exclusion, where the animals do not have access to vegetation. To analyze the data, we used the ANOSIM test to compare differences between treatments in open plots (open treatment) and closed ones (excluding treatment). Then Student t test was applied to compare the frequency of occurrence and growth of each species between treatments (open and exclusion). A new Student t test was used to evaluate the seasonal growth of the species in open and exclusion treatments, grouping data by cold and warm seasons. The floristic inventory recorded 119 species, being 77 phytosociological and 33 methodology exclusion cage. The species Achyrocline satureioides (Lam) DC., Cyperus esculentus L., Cyperus surinamensis Rottb., Ipomoea cairica (L.) R.Br., Kyllinga vaginata Lam. and Sesbania cf. brasiliensis (Cav.) Burkart showed significant differences (p <0.05) in frequency of occurrence between open repair and exclusion. Whereas C. esculentus, C. surinamensis, Ischaemum minus J. Pers., K. vaginata., Paspalum distichum L., S. cf. brasiliensis, Solidago chilensis Meyen and Tibouchina sp. Aubl. differed significantly (p <0.05) in their growth, also between open repair and exclusion. In cold seasons, the species Canna glauca L., Solanum americanum Mill. and S. chilensis showed growth with significant differences (p <0.05) between autumn and winter, while S. chilensis and Tibouchina sp. growth differed significantly (p <0.05) in the warm seasons, between spring and summer. We found that the coverage of the plant community remains stable throughout the year, but when we focus on each species separately, we realize that some of them differ in their frequency of occurrence and / or growth. Thus, we can say that the. Taim wetland has a functional dynamics, which gets its ecologically balanced patterns.
8

Reindeer in the archipelago of Holmöarna : Abundance of habitats and how reindeer have utilized them during winter 2015-16 and summer 2016

Årdahl, Kerstin January 2017 (has links)
In the winter 2015/2016, about 700 reindeer were winter grazing on the islands of Holmöarna. Since the islands had not been used for reindeer grazing for more than 100 years, this is a unique opportunity to study how reindeer influence the vegetation that has developed in the absence of reindeer. Moreover, it also means that all reindeer faeces depositions and grazing damages originate from the last year. Most of the reindeer grazing occurred on Ängesön and Grossgrunden, at least during winter, due to lichen rich habitats. To investigate which habitats were available for reindeer, the abundance of these habitats and which resources they provide, 239 randomly selected study sites were investigated. To find out reindeer utilization of resources and impact on vegetation, all faecal droppings from reindeer were counted. Also, lichen height, lichen cover, lichen volume, grazing damages of lichens and vegetation, trampling, and digging, were recorded at every study site. Old-grown spruce forest was the most abundant habitat, providing reindeer with ground lichens, bilberries and epiphytic lichens. Pine forest, rich in ground lichens, was the most preferred and used habitat based on lichen cover and lichen volume, lichen damage and trampling. NMSD ordination confirmed a strong relationship between lichen height and lichen cover, i.e. lichens were heavily grazed in every habitat where lichens were recorded. Reindeer depositions of dungs and pellets were found in all habitats, but were most abundant in spruce forest with ground lichens. Strong relationships between lichen damages, digging signs and reindeer pellets confirmed more activities where lichens were abundant. Grazing of bilberry shoots and trampling, both indications of summer activities by reindeer, were also closely associated, indicating that bilberry shoots was an important food resource in summer on these islands. In the light of my result, the islands of Holmöarna have good provision for reindeer, in winter by richness of ground lichens in pine forest and old spruce forest, and summer primarily by bilberries in old grown spruce forest, mixed forest and pine forest with Vaccinium ssp. Although almost all suitable habitats show signs of reindeer activities after only one year, there is still abundant winter and summer food resources available for future grazing. There is thus plenty of resources available for reindeer on the islands of Holmöarna and reindeer are able to utilize them. If they are suitable to use for reindeer grazing in the future is thus more dependent on logistic problems like difficulties in transporting the reindeer from mainland to the islands.
9

Sustainability of nature-based tourism

Törn, A. (Anne) 04 December 2007 (has links)
Abstract Nature-based tourism has increased considerably during recent years, which has raised questions about the tolerance of ecosystems experiencing growing visitor numbers. The present thesis focuses on the ecological and social sustainability of nature-based tourism in protected areas and their surroundings. The objective of the ecological studies was to determine the effects of tourism on vegetation, soils and risk of introduction of alien plant species. The social survey investigated whether opinions concerning nature conservation and tourism by local people are dependent on socio-economic and demographic factors. The studies were carried out in Oulanka and Pallas-Ounastunturi National Parks, and in the Ruka and Syöte regions, in northern Finland. This research demonstrated that nature-based tourism (hiking, horse-riding and skiing) affected boreal forests, altering vegetation, soils and trail networks. The major effects were; reduction in vegetation cover, including of different life-forms, changes in plant species composition, soil chemistry and soil erosion. Trampling decreased plant cover more on slopes compared to flat terrain. Moreover, downward trampling reduced the plant cover more than did upward trampling. In addition, horse riding resulted in the introduction and establishment of a range of alien plant species. In general, ecological changes due to nature-based tourism were inevitable even when there were limited numbers of visitors. Respondents to the survey were classified into three groups according to their opinions concerning nature conservation and tourism development: (i) supporters of nature conservation, (ii) critical to nature conservation and (iii) critical to tourism development. The majority of respondents were supporters of nature conservation. However, opinions were strongly dependent on the socio-demographic background of the respondents, such as residential area, age, level of education and indigenousness. Since the impacts of tourism were dependent on the characteristics of plants and habitats and the quality of activities, case-specific planning, monitoring and rapid responses are the most efficient methods in avoiding irreversible environmental damages. Furthermore, close co-operation between different stakeholders and detailed scientific information about the ecological, economic and social elements of sustainability are needed to promote a sustainable development of nature-based tourism.
10

Understanding the Interaction Between Habitat Use of Feral Horses and the Abundance of Greater Sage-Grouse in the Great Basin

Carver, Mikiah R. 21 July 2021 (has links)
Environmental impacts of feral horses (Equus caballus) are a subject of conservation concern and controversial national policy. In North America, feral horses are considered an invasive species where they impact rangelands of the arid and semi-arid western United States. The greater sage-grouse (Centrocercus urophasianus) is a native sagebrush obligate bird species that relies on sagebrush habitats to sustain viable population levels. Recent literature suggests that feral horse presence can have a notable effect on the fitness of native and sagebrush obligate species throughout the arid and semi-arid western United States. The purpose of this thesis was to assess the potential impact of feral horses on population patterns and on late-brood rearing habitat of greater sage-grouse throughout the Great Basin. This was accomplished by pairing known sage-grouse use sites (leks and late brood-rearing habitat) to random sites for comparison. Within each pair, one site was located within Herd Management Area (HMA) boundaries (with assumed horse presence) while the other was located outside (with assumed horse absence). We then assessed lek attendance throughout the state of Nevada and compared attendance rates to known horse population estimates. Furthermore, paired late brood-rearing habitat sites were compared to one another to assess the effect of horse and cattle presence on habitat quality and characteristics. We determined that mean sage-grouse population size at leks is higher (9.14 ± 1.04 males) within HMA boundaries compared to areas outside of HMA boundaries (6.55 ± 0.74 males). Considering late brood-rearing habitat, we determined that statistical differences have occurred between horse and non-horse use sites in the following comparisons: annual grass frequency, percent annual grass cover, dung frequency, total plant height, vegetative height, and horse and cattle dung density. We suggest that feral horse presence can impact sage-grouse habitat, however, a more clear understanding of horse effects on rangeland wildlife habitat is needed to assess actual impacts on wildlife populations in consideration of multiple use management decisions.

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