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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

The effects of improvement of upland, marginal grasslands on breeding waders (Charadriiformes) and invertebrates

Baines, David January 1988 (has links)
Between 1985 and 1987, ten areas of upland, marginal grassland were surveyed for breeding waders; eight areas west of the Pennines in the Eden Valley, Cumbria, and two East of the Pennines at Alston, Cumbria and Teesdale, Co. Durham. Grassland improvement resulted in the virtual disappearance of snipe and marked decreases in both the density and the proportion of fields used by breeding lapwing, curlew and redshank. The absence of snipe following improvement was due to land drainage, whereas reduced curlew densities resulted from vegetation changes, redshank were relatively unaffected provided wet areas persisted nearby. Data on lapwing breeding success were obtained from a study of 637 clutches. Fewer clutches suffered predation on unimproved than on improved pastures and resulted in higher hatching success. This, combined with more failed clutches being replaced and better survival by young chicks, resulted in higher productivity on unimproved than on improved pastures. The role of predation in reducing hatching success was confirmed experimentally. In addition, more clutches were destroyed by agricultural activities on improved than on unimproved meadows, resulting in lower productivity. Productivity on unimproved areas was enough to sustain the population, but was insufficient on improved areas and it is suggested that this, together with high philopatry, causes the decline in density of lapwings on improved areas. Invertebrates were sampled by chemical expellents, soil cores and pitfall traps. Grassland improvement resulted in increased earthworms and beetles other than carabids, but decreased spiders and carabic beetles. Fewer species of spider after improvement were largely due to lowered vegetation architecture diversity, whilst fewer species of tipulids resulted from reduced soil moisture and loss of food plants. Changes in species composition were apparent when comparing the seasonal pattern of pitfall catches on unimproved and improved grassland.
2

Exposure of migratory shorebirds to organophosphorus and carbmate pesticides at migratory stopover and non-breeding sites in the western hemisphere

Strum, Khara M. January 1900 (has links)
Master of Science / Department of Biology / Brett K. Sandercock / Monitoring programs indicate that numerous shorebird populations are subject to on-going declines. The U.S. Shorebird Conservation Plan lists twenty-seven shorebird species as species of high concern and seven as highly imperiled, including the Buff-breasted Sandpiper (Tryngites subruficollis). One hypothesis for ongoing population declines is exposure to toxic chemicals and pollutants. The purpose of this project was to characterize plasma cholinesterases (ChEs) of migratory shorebirds and address potential exposure to organophosphorus (OP) and carbamate (CB) pesticides. Consumption or contact with these pesticides can cause mortality and a variety of sub-lethal effects. Buff-breasted Sandpipers and other upland shorebirds are particularly likely to encounter agrochemicals due to their habitat use at the non-breeding grounds. I sampled migratory shorebirds over three seasons, during north- and southbound migration in 2006 and 2007 in Texas, Kansas, and Nebraska and during the non-breeding season in 2007 in Argentina, Uruguay, and Paraguay. I collected blood samples and footwashings from reference sites, where OP and CB pesticides were not used, and agricultural sites, where these two insecticides were recommended for control of crop pests. I assessed several variables known to affect plasma ChE activity including body size, date of capture, time of capture, condition, sex, and region. Small-bodied species had higher levels of ChE activity in plasma than large-bodied species. Plasma ChE activities varied with date of capture in 3 of 5 species sampled in North America. Sex differences were significant in 1 of 4 species tested. Plasma acetylcholinesterase (AChE) activity was higher among White-rumped Sandpipers sampled in North America but there was no difference between regions among Buff-breasted Sandpipers. Time of capture and individual condition did not affect plasma ChE activity. Estimates of exposure to ChE inhibitors were addressed in five species. Plasma AChE and butyrylcholinesterase (BChE) activities of Buff-breasted Sandpipers were lower at agricultural sites in South America but BChE activity was higher at agricultural sites in North America. There were no differences between sites in four other species tested. A meta-analysis across all species indicated that in 4 of 6 comparisons habitat type had a negative effect on AChE activity consistent with exposure to ChE inhibitors but there was a regional positive effect of agricultural habitat on BChE activity in North America. Comparison of body mass between sites suggested that use of habitats with potential pesticide application did not affect mass gain. Project results suggest that 1 of 5 shorebird species tested was exposed to ChE-inhibiting pesticides at the non-breeding grounds and future monitoring is necessary to assess potential effects at the population level. This study highlights the importance of complete sampling and addressing variability in plasma ChEs before making estimates of exposure to OP and CB pesticides. It provides the first estimates of migratory shorebird exposure to OP and CB pesticides, a potential conservation issue. Future research should include continued monitoring of Buff-breasted Sandpiper ChE levels and habitat use. Other sources of anthropogenic declines such as habitat loss and illegal hunting should be investigated for species that did not show evidence of exposure.
3

Ecological and anthropogenic constraints on waterbirds of the Forth Estuary : population and behavioural responses to disturbance

Dwyer, Ross Gordon January 2010 (has links)
Disturbance from engineering works is an increasing problem in terrestrial and marine ecosystems throughout the world. Many reported declines in population size, breeding success and body condition have been diagnosed as the result of anthropogenic disturbance, however little is known about the effect of long-term disturbance from large-scale engineering works. Understanding the mechanisms by which animals respond to anthropogenic activities is fundamental to explaining interactions, and resolving potential conflicts between humans and wildlife. This thesis focuses on the factors affecting the habitat use and foraging decisions in wintering shorebirds and wildfowl. The first half of this thesis considers the direct and indirect impacts on waterbirds of a major engineering project in central Scotland; construction of the new Clackmannanshire Bridge at Kincardine-on-Forth. For individual bird species in close proximity to the bridge site, round-the-clock construction work had consequences ranging from neutral to considerably negative. Cormorant Phalacrocorax carbo declined in the area, probably as a result of the disturbance of an important low tide roost. Redshank Tringa totanus, previously abundant in the prey-rich areas adjacent to the construction site, were displaced into poorer areas for most of the construction period; where they may also have suffered from increased interference competition and elevated risk from raptorial predators. Some positive effects of industrial development were also revealed; radio-transmitters combined with tilt-switch posture sensors indicate that Redshank were able to capitalise on the improved nocturnal visibility in areas around Grangemouth docks to assist with foraging and predator detection. Evidence is presented that birds switched foraging strategy (from sight to touch feeding) depending on ambient light levels; whereby artificial light was used in a similar manner to moonlight to assist with prey detection. Redshank also avoided riverine areas at night that were used frequently by day, probably in response to an elevated threat from nocturnal predators. As the predator landscape changes from day into night, birds adopt different strategies to minimise the risk from nocturnal predators. It is clearly important, therefore, that information on nocturnal distributions is available to inform decisions on site management, especially where anthropogenic activity continues throughout the diel cycle. Behavioural decisions were shown to vary widely within a species depending on individual state, metabolic demands and previous exposure to human disturbance. Prey resources were shown to change dramatically over the course of a winter. In response to this decline, the home range of Redshank contracted over a winter season. Similarly, animals responded less and took greater risks in response to experimental disturbance events later in the winter than earlier in the winter, and on days when the temperature was lower. This effect was strongest for individuals occupying heavily disturbed areas, which were possibly already compensating for lost feeding time and a negative energy balance. The results were consistent with the hypothesis that those individuals that respond most obviously to human disturbance were those least likely to suffer fitness consequences. This is the opposite from what is commonly assumed when behaviour is used as an index of disturbance impacts, most notably in the use of flush distance in the design of wildlife buffer zones. In conclusion, this study demonstrated various negative impacts of disturbance, including local displacement, due to construction activity on overwintering waterbirds. It also revealed two key, but poorly understood, phenomena relating to mechanisms for coping with anthropogenic disturbance: routine utilisation of artificial light to extend night-time feeding opportunities amongst Redshank and an adaptive flexibility in escape responses across a range of species under varying conditions of risk.
4

Ecology and conservation of breeding lapwings in upland grassland systems : effects of agricultural management and soil properties

McCallum, Heather M. January 2012 (has links)
Agriculture is the principal land use throughout Europe and agricultural intensification has been implicated in large reductions in biodiversity, with the negative effects on birds particularly well documented. The lapwing (Vanellus vanellus) is one such species where changes in farming practices has reduced the suitability and quality of breeding habitat, leading to a drop in population size that has been so severe as to warrant its addition to the Red List of Birds of Conservation Concern in the UK. Lowland areas, where agricultural intensification has generally been most pronounced, have been worst affected, however, more recently declines in marginal upland areas, previously considered refuges for breeding wader populations, have been identified. An upland livestock farm in Stirlingshire that uses an in-bye system of fodder crop management and has unusually high densities of breeding lapwings provides a basis for this project to test causal hypotheses for the decline of upland lapwing populations and to identify potential conservation management solutions. Specifically this farm plants a forage brassica in an in-bye field for two consecutive years, followed by reseeding with grass and seven, out of sixteen, in-bye fields have undergone this regime at the study site since 1997. Fields that had undergone fodder crop management supported almost 60% more lapwings than comparable fields that had not previously been planted with the fodder crop. Lapwing density was highest in the year after the fodder crop was planted, once it had been grazed, which results in a high percentage of bare ground, likely to be attractive to nesting lapwings. Lapwing densities remained above that which occurred in fields that had not undergone fodder crop management for a further four years after the field had been returned to grass. The effect of management on lapwing food resources and nesting structure was tested through a field experiment; liming increased the abundance of Allolobophora chlorotica, an earthworm species that was associated with chick foraging location at the study site, suggesting that lapwings may benefit from liming conducted as part of fodder crop management. The relationship between lapwings and soil pH is further explored across 89 sites on mainland Scotland, using soil property data to improve the predictive power of habitat association models, something which has not previously been done for any farmland bird. Adding soil and topographical data to habitat models, based on established relationships between breeding lapwings and their habitat, improved model fit by almost 60%, indicating that soil properties influence the distribution of this species. The density of breeding lapwings was highest at higher altitude sites, but only when the soil was relatively less peaty and less acidic, providing further support for the hypothesis that agricultural liming benefits lapwings. In addition to assessing the conservation benefit of fodder crop management, the economic costs are also considered. Fodder crop management provides a source of livestock fodder in the autumn and winter during a period when forage demands outstrip grass growth, and ultimately improves the grazing quality of the grass that is replaced; this system currently operates outside of any agri-environment scheme (AES). However, at the study site, planting of the fodder crop and grass is delayed to avoid agriculture operations during the breeding season, which reduces yield and hence profitability. An initial estimate of £200 ha-1 is suggested as an incentive to encourage wider adoption of fodder crop management in a “lapwing friendly” manner, although further work is required to determine if this payment level is appropriate and the current method of AES implementation may limit the suitability of fodder crop management as an AES. The results indicate that agricultural liming could benefit breeding lapwings in pasture fields where soil pH falls below pH 5.2, by increasing earthworm abundance. Where soil pH is below pH 5.2, liming should provide a cost effective mechanism for farmers to improve grass yields. Regular soil testing and liming in response to low pH, within improved or semi-improved grassland fields, where management activities such as use of nitrogen fertiliser can contribute to soil acidification, should be advocated to farmers in marginal areas as a mechanism for improving grass productivity whilst potentially benefitting breeding lapwing and other species where earthworms contribute significantly to their diet.
5

Influência das perturbações antrópicas sobre a escolha de locais de descanso de aves limícolas, Nordeste do Brasil

Silva, Leomyr Sângelo Alves da 25 February 2016 (has links)
Submitted by Jean Medeiros (jeanletras@uepb.edu.br) on 2017-03-08T12:01:57Z No. of bitstreams: 1 PDF - Leomyr Sângelo Alves da Silva.pdf: 8192669 bytes, checksum: 4a337a15070f7bb47be66578de81125b (MD5) / Made available in DSpace on 2017-03-08T12:01:57Z (GMT). No. of bitstreams: 1 PDF - Leomyr Sângelo Alves da Silva.pdf: 8192669 bytes, checksum: 4a337a15070f7bb47be66578de81125b (MD5) Previous issue date: 2016-02-25 / Coordenação de Aperfeiçoamento de Pessoal de Nível Superior - CAPES / Estuarine habitats are critical in the life cycle of shorebirds. In estuaries, these birds perform daily movements, feeding in intertidal zones at low tides and lounging on beaches and other supratidais areas during high tides. To reduce energy costs, the rest rooms must be near the feeding areas, but many of these sites are used by people for recreational activities and other occupations which probably disturb the birds. This study aimed to investigate the choices made by waders as their resting places near and adjacent to the estuary of the River Paraiba, northeastern Brazil. Were performed 4 monthly census from October 2014 to May 2015, quantifying the data abundance of birds and anthropogenic disturbances in two beaches of Paraíba coast, and in an artificial habitat (roof) that was used during the wintering period in the area urban Cabedelo, PB, Brazil. Censuses were carried out simultaneously in all counting sites, and were divided into day weekend and midweek. four species were recorded of wading birds belonging to the family Charadriidae (Charadrius semipalmatus and Charadrius collaris) and Scolopacidae (Calidris alba and Calidris pusilla). The species C. semipalmatus was the most representative for the study areas. The mean abundance of birds that occupied the roof were higher during the weekends, days that also there were major disturbances on the beaches from the days midweek when they were recorded smaller amounts of recreational activity. However, despite the positive influence on the increase of disturbances in poultry artificial housing, as well as the variation in the abundance of birds who used two beaches, the effects were significantly weaker, as shown by the dependency analysis. This study suggests that the number of anthropogenic occupations in both beaches, probably were not enough to scare away the birds nearctic areas rests indicating that the birds that have been using the artificial habitat are coming from other areas of Paraíba coast. In addition, we emphasize the importance of a greater number of sample areas for future research that seek to address the waders response in relation to anthropogenic influences, as possibly the small geographical scale of our study may have influenced our data. / Hábitats estuarinos são fundamentais no ciclo de vida das aves limícolas. Nos estuários, estas aves realizam movimentos diários, se alimentando nas zonas intertidais durante as marés baixas e descansando nas praias e outras áreas supratidais durante as marés altas. Para reduzir gastos energéticos, os locais de descanso precisam ser próximos às áreas de alimentação, porém muitos destes locais são utilizados por pessoas para atividades recreativas e outras ocupações, que, provavelmente, perturbam as aves. O presente estudo teve por objetivo investigar as escolhas feitas por aves limícolas quanto aos seus locais de descanso próximo e adjacentes ao estuário do Rio Paraíba, Nordeste do Brasil. Foram realizados 4 censos mensais entre outubro de 2014 à maio de 2015, quantificando os dados de abundância de aves e os distúrbios antrópicos em duas praias da costa paraibana, e em um habitat artificial (telhado) que foi utilizado durante o período de invernada na zona urbana de Cabedelo-PB, Brasil. Os censos foram realizados simultaneamente em todos os locais de contagem, e foram distribuídos em dias de final de semana e meio de semana. Foram registradas quatro espécies de aves limícolas pertencentes as famílias Charadriidae (Charadrius semipalmatus e Charadrius collaris) e Scolopacidae (Calidris alba e Calidris pusilla). A espécie C. semipalmatus foi a mais representativa para as áreas de estudo. As médias das abundâncias de aves que ocuparam o telhado foram maiores durante os finais de semana, dias em que também verificaram-se os maiores distúrbios nas praias em relação aos dias no meio da semana, quando foram registradas menores quantidades de atividade recreativas. No entanto, apesar dos distúrbios influenciarem positivamente o aumento de aves no habitat artificial, assim como a variação da abundância de aves que utilizaram as duas praias, os efeitos foram estatisticamente fracos, como revelado pela análise de dependência. O presente estudo sugere que o número de ocupações antrópicas nas duas praias, provavelmente não foram suficientes para afugentar as aves neárticas das áreas de descansos indicando que, as aves que vem utilizando o habitat artificial estão vindo de outras áreas da costa paraibana. Além disso, ressaltamos a importância de um maior número de áreas amostrais em futuras pesquisas que busquem abordar a resposta de aves limícolas em relação às influências antrópicas, já que, possivelmente a pequena escala geográfica de nosso estudo pode ter influenciado nossos dados.
6

Brushanen (Calidris pugnax) i Sverige : Hur populationen förändrats de senaste 20 åren och orsakerna till detta, samt hur turism kring brushanen skulle kunna utvecklas

Ransgart, Emmy January 2020 (has links)
The purpose of the study is to determine how the population of the ruff in Sweden has changed over the past 20 years and which reasons for the changes, if any, there are. The study also includes how the tourism regarding the ruff in Sweden is today and how it could be developed. The study is based on non-fiction literature, reports, diagrams and interviews. The population of the ruff in Europe has declined over the past years. In Sweden, the breed is classified as vulnerable on the IUCN Red list of threatened species due to the fast decline. The results show that the population of the ruff has changed in the whole country of Sweden. Today almost 99% of the population lives on tundra and wetlands in northern Sweden. Most of the decline has occurred in the south of Sweden where the population almost is extinct. In northern Sweden, the population also has declined but not as much as in the south. Nowadays the ruff only breeds in 8 out of 22 counties it used to occur in. Reasons of the decline are primarily changes in habitats, drainage of watercourses and wetlands, urbanization, agriculture and forestry. The decline also depends on changes along the migration routes and in northwest Africa where the breed winters. Also, climate change and higher predation are reasons for the decline. No tourism with focus on the ruff exists in Sweden today. There is a potential in developing a specific tourism focused on the ruff lek.
7

Estimativa da radiação de ondas longas incidente na Amazônia: uma análise espectral. / Downward longwave radiation estimate in Amazonia: a spectral analysis.

ANDRADE, Antonio Marcos Delfino de. 15 August 2018 (has links)
Submitted by Emanuel Varela Cardoso (emanuel.varela@ufcg.edu.br) on 2018-08-15T16:36:49Z No. of bitstreams: 1 ANTONIO MARCOS DELFINO DE ANDRADE – TESE (PPGMet) 2017.pdf: 3321439 bytes, checksum: 641b9755396203a4dd27ac62503ca9e8 (MD5) / Made available in DSpace on 2018-08-15T16:36:49Z (GMT). No. of bitstreams: 1 ANTONIO MARCOS DELFINO DE ANDRADE – TESE (PPGMet) 2017.pdf: 3321439 bytes, checksum: 641b9755396203a4dd27ac62503ca9e8 (MD5) Previous issue date: 2016-02-19 / Capes / A radiação de onda longa incidente (L↓) é seguramente a componente do balanço de radiação mais difícil de ser medida. Portanto, diferentes formulações têm sido propostas para estimá-la. Desta maneira, avaliou-se neste estudo o desempenho de várias formulações para a estimativa dos fluxos de L↓ e sua a interação com outras variáveis medidas, bem como as interações da temperatura do ar e da pressão de vapor d’água junto à L↓. Neste estudo foi utilizada a análise pela transformada em ondeletas (TO) como ferramenta matemática para a análise de variações locais de energia dentro das séries temporais aqui estudadas, pela sua decomposição no tempo-frequência-espaço. Para investigar a correlação entre duas séries (L↓ com a temperatura do ar e da L↓ medida com as estimadas por cada modelo), empregou-se transformada cruzada em ondeletas e a coerência e fase em ondeletas. Os dados deste estudo compreendem o período de 01 de janeiro a 31 de dezembro de 2009, e são provenientes da torre micrometeorológica (K34) pertencente ao Experimento de Grande Escala da Biosfera Atmosfera na Amazônia (LBA) em Manaus, Amazonas. A TO revelou que no período de 36 horas, para todo período analisado, um persistente, homogêneo e forte espectro energético entre a L↓ e a temperatura do ar, onde se constatou uma sinergia entre essas variáveis. Constatou -se ainda que a precipitação e a pressão de vapor d’água exercem bastante influencia nos fluxos de L↓, principalmente na estação chuvosa. A análise através da transformada cruzada e de coerência e fase em ondeletas no período de 32 a 64 horas. Já nos modelos ajustados foram no período de 16 a 64 horas. Os modelos propostos para condições de céu claro, com o uso de seus coeficientes originais, mostraram tendência em subestimar os fluxos de L↓ medidos. Com os ajustes nos coeficientes, os modelos expuseram uma melhora nas estimativas nos fluxos de L↓.Para os modelos propostos para condições de céu nublado, estes exibiram um desempenho regular. / The downward longwave radiation (L↓) component really is difficult of the net radiation the measured. Therefore, different parameterizations have been proposed to estimate it. Thus, in this study we evaluated the performance of various parameterizations for the L↓ flows estimated and their interaction with other variables measured as well as the air temperature and water vapour pressure interactions with L↓. In this study we used by wavelet transform (WT) analysis as mathematical tool for energy of local variations analysis in the studied time series here by their frequency time-space decomposition. To investigate the correlation between two series (L↓ with air temperature and between L↓ measured with estimated), we used crosswavelet transform and coherency wavelets and phase angle. The datasets used in this study are of the January 01 to December 31 of 2009, measured from micrometeorological tower (named K34) controlled by Large Scale Biosphere Atmosphere experiment in Amazonia (LBA) from Manaus city, Amazonas. The WT showed that in 36 hours period, for the entire period analyzed, a persistent, smooth and strong energy spectrum between L↓ and the air temperature, which demonstrated a synergy between these variables. It was also found that precipitation and water vapour pressure exert enough on L↓ flows influence, especially in the wet season. The crosswavelet transform and coherency wavelets and phase angle analysis at 32 to 64 hours period. Already in adjusted models were in the 16-64 hours period. With the adjustable coefficients, according to the environmental study area conditions, the models presents an improvement in the L↓ flows estimates. The cloudy skies models proposed, they exhibited a regular performance.
8

Modulação regional das chuvas no Estado do Maranhão.

COSTA, Adriana de Souza. 14 May 2018 (has links)
Submitted by Emanuel Varela Cardoso (emanuel.varela@ufcg.edu.br) on 2018-05-14T20:21:01Z No. of bitstreams: 1 ADRIANA DE SOUZA COSTA – DISSERTAÇÃO (PPGMET) 2016.pdf: 6197666 bytes, checksum: 77b57b9618b2649efa4e6fbe2526f94f (MD5) / Made available in DSpace on 2018-05-14T20:21:01Z (GMT). No. of bitstreams: 1 ADRIANA DE SOUZA COSTA – DISSERTAÇÃO (PPGMET) 2016.pdf: 6197666 bytes, checksum: 77b57b9618b2649efa4e6fbe2526f94f (MD5) Previous issue date: 2016-02-29 / Capes / O Estado do Maranhão está localizado numa zona de transição entre o semiárido nordestino, a Amazônia quente e úmida e os chapadões do Brasil central, dando ao Estado características peculiares. Embora, o Estado não se encontre no contexto do polígono das secas, por apresentar condições climáticas bem definidas, a distribuição espacial e temporal das chuvas são bastantes irregulares, o que submete o sistema agrícola da região a sérios problemas, com impactos econômicos e sociais significativos. Diante dessas particularidades, o objetivo do estudo foi analisar e compreender a variabilidade da precipitação e relacioná-la com a TSM e outros sistemas meteorológicos que influenciem as chuvas no Estado. Para tal, empregou-se o método da Transformada de Ondeletas (TO) para identificar em diferentes escalas de oscilações o sinal da precipitação e da TSM, e assim apontar os sistemas que contribuem nas diferentes nas escalas de tempo. Os resultados mostraram no espectro global de energia da ondeleta que o ciclo anual é o dominante em todas as localidades analisadas. E, que além da escala anual observam-se também interações com as escalas sazonal, intrasazonal, semi-anual, bianual e até decadal. No tocante a TSM do Pacífico Equatorial, a escala anual é mais intensa no setor leste do oceano, decrescendo no sentido leste-oeste, onde a escala decadal se torna mais acentuada. A relação entre a chuva nas regiões homogêneas (RH) do Maranhão e a TSM do oceano Pacífico Equatorial mostrou que existe correlações importantes entre as mesmas. Ou seja, as áreas do Niño que apresentaram as maiores correlações com as RH foram: Niño 3 com a RH1(correlação r = -0,72), com a RH2 (correlação r = -0,65), com a RH3 (correlação r = -0,69), com a RH4 (correlação r = -0,53), e Niño 1+2 com a RH5 (correlação r = -0,52). / The State of Maranhão is located in a transition zone between the semi-arid northeast, the hot and humid Amazon and the plains of central Brazil, giving the state peculiar characteristics. Although the state is not in the polygon the context of drought, have welldefined climatic conditions, the spatial and temporal distribution of rainfall is quite irregular, which submits the agricultural system of the region to serious problems, with significant economic and social impacts . Given these characteristics, the objective of the study was to analyze and understand the variability of precipitation and relate it to the TSM and other weather systems that influence rainfall in the state. To this end, we used the method of Wavelet Transform (TO) to identify different scales fluctuations sign of precipitation and TSM, and thus point the systems involved in the different time scales. The results showed the overall spectrum of the wavelet energy that the annual cycle is the dominant in all analyzed locations. And that in addition to the annual scale also observe up interactions with seasonal scales, intraseasonal, semi-annual, bi-annual and decadal up. Regarding the TSM Equatorial Pacific, the annual scale is more intense in the east of the ocean sector, decreasing from east to west, where the decadal scale becomes more pronounced. The relationship between rainfall in homogeneous regions (HR) of Maranhao and the ocean TSM Equatorial Pacific showed that there is significant correlation between them. Ie areas of Niño with the highest correlations with HR were: Niño 3 with RH1 relationship (r = -0.72), with RH2 relationship (r = -0.65), with RH3 (correlation r = -0.69), as RH4 (correlation r = -0.53) and Nino 1 + 2 with RH5 relationship (r = -0.52).
9

Vyhodnocení využívání vybraných agroenvironmentálních dotačních titulů v rámci Jihočeského a Plzeňského kraje / Utilizing of selected agri-environment measures in the South Bohemian and Pilsen Region

MUDRÁKOVÁ, Tereza January 2010 (has links)
Theoretical part of the diploma thesis (review) is focused on historical development of the Common Agricultural Policy (reforms from the years 1999 and 2003 are emphasized) and on the comparison of the agri-environment schemes (AES) of the Czech Republic, Slovak Republic, and Austria. The aim of the review was to summarize the processes, which led to the recent form of AES. In practical part of the thesis measures, which support maintaining and increasing of populations of ground game and birdlife, i.e. measures Catch Crops, Rich Seed Habitat (Biobelt), and Bird Area on Grasslands were evaluated. Data from Paying Agency SZIF were used. The study covers both, the (shortened) programming period 2004-2006 and the programming period 2007 {--} 2013 (years 2004 {--} 2008). Thesis is focused on region NUTS II Southeast. The following indicators were analysed: interest of the farmers in the selected AES measures, area on which the measures were carried out and amount of the financial support spent to support individual measures. Finally, steps to optimize the use of financial resources are suggested. Catch Crops are used as a measure on arable land. The highest interest of the farmers in Catch Crops was observed in the year 2004, when the largest number of the farmers entered this measure. The interest was decreasing in the following years (especially in the years 2007 and 2008, when the endowment was lowered). Catch Crops cover 6 {--} 8 % of the arable land of the region and the area has been increasing in time. Biobelt is only sporadically used measure (probably because of the underestimation of the costs), but interest in it (albeit low) has been increasing during the whole period. Measure Bird Area on Grasslands is restricted to nesting areas of Corncrake (Crex crex) and Waders (Charadrii). In NUTS III South Bohemian Region, the measure was applied on approximately 27 % of the area where it potentially can be used during the whole observed period. In NUTS III Plzeň Region, the area increased from 26% in the years 2004 {--} 2006 to 60 % in the years 2007 and 2008.
10

The restoration of intertidal habitats for non-breeding waterbirds through breached managed realignment

Crowther, Amy E. January 2007 (has links)
Conservation of intertidal habitats in the UK is vital in order to continue to support nationally and internationally important populations of non-breeding waterbirds. Historic reclamation for agriculture and industry has resulted in the loss and degradation of large areas of these intertidal habitats in estuaries and they continue to be threatened by sea-level rise. Managed realignment is one method which is increasingly being used to restore intertidal habitats. As managed realignment is a relatively new restoration technique, the extent to which knowledge of the biology of estuaries is applicable to managed realignment sites is unclear. Habitat restoration is often unsuccessful or incomplete, so a detailed knowledge of both the natural system and the characteristics of restored systems will usually be necessary to recreate fully-functional estuarine habitats. This thesis focuses on Nigg Bay Managed Realignment Site (Nigg Bay MRS), the first managed realignment site in Scotland, and follows the first four years of ecological development to gain an understanding of how breached realignment can be used to restore intertidal habitats to support non-breeding waterbirds. This thesis has six major aims: (i) to describe the development of saltmarsh, (ii) to describe the development of intertidal flat, (iii) to describe the colonisation by non-breeding waterbirds (iv) to determine how tidal cycle and weather affect patterns of waterbird use, (v) to determine which factors affect the spatial distribution of waders and finally (vi) to determine the patterns of use by individual birds. Four summers after the re-establishment of tidal conditions, almost all of the saltmarsh species recorded on the nearby saltmarsh had colonised Nigg Bay MRS, although recognisable communities had yet to establish. Three winters after the re- establishment of tidal conditions in Nigg Bay MRS, the sediments had a significantly smaller particle size and higher organic matter content compared to the fine sands of the adjacent intertidal flats. The intertidal invertebrate community also differed from the adjacent intertidal flats. Nigg Bay MRS attracted large numbers of non-breeding waterbirds and supported each of the most common wader and wildfowl species present in the wider estuary. Nigg Bay MRS performs a number of important functions for non-breeding waterbirds by: (i) providing a foraging and resting habitat when the tide is absent and intertidal sediments in Nigg Bay are exposed; (ii) providing a foraging resource as the tide passes over the intertidal sediments within the site once the intertidal flats in Nigg Bay are inundated; and (iii) providing a high tide roosting site. On days with low temperatures and high wind speeds, more waterbirds use Nigg Bay MRS, suggesting that it is likely to be providing sheltering benefits. Nigg Bay MRS also provides top-up feeding habitat. The factors that often influence the spatial distributions of waders in estuaries appear to be operating within Nigg Bay MRS. Wader densities are greater on the intertidal flats when they are accessible than on the saltmarsh. Wader densities are also greatest close to creeks and drainage channels, possibly due to higher invertebrate densities, more accessible prey or sheltering benefits. Colour-ringing and radio-tracking of Common Redshank established that Nigg Bay MRS has a subset of regular users, including both adults and juveniles, and the wader assemblage at night may differ from the assemblage during the day. These findings are discussed in terms of the implications for locating, designing and managing future managed realignment projects.

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