2 resultados para monarch butterflies

em Glasgow Theses Service


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Although the value of primary forests for biodiversity conservation is well known, the potential biodiversity and conservation value of regenerating forests remains controversial. Many factors likely contribute to this, including: 1. the variable ages of regenerating forests being studied (often dominated by relatively young regenerating forests); 2. the potential for confounding on-going human disturbance (such as logging and hunting); 3. the relatively low number of multi-taxa studies; 4. the lack of studies that directly compare different historic disturbances within the same location; 5. contrasting patterns from different survey methodologies and the paucity of knowledge on the impacts across different vertical levels of rainforest biodiversity (often due to a lack of suitable methodologies available to assess them). We also know relatively little as to how biodiversity is affected by major current impacts, such as unmarked rainforest roads, which contribute to this degradation of habitat and fragmentation. This thesis explores the potential biodiversity value of regenerating rainforests under the best of scenarios and seeks to understand more about the impact of current human disturbance to biodiversity; data comes from case studies from the Manu and Sumaco Biosphere Reserves in the Western Amazon. Specifically, I compare overall biodiversity and conservation value of a best case regenerating rainforest site with a selection of well-studied primary forest sites and with predicted species lists for the region; including a focus on species of key conservation concern. I then investigate the biodiversity of the same study site in reference to different types of historic anthropogenic disturbance. Following this I investigate the impacts to biodiversity from an unmarked rainforest road. In order to understand more about the differential effects of habitat disturbance on arboreal diversity I directly assess how patterns of butterfly biodiversity vary between three vertical strata. Although assessments within the canopy have been made for birds, invertebrates and bats, very few studies have successfully targeted arboreal mammals. I therefore investigate the potential of camera traps for inventorying arboreal mammal species in comparison with traditional methodologies. Finally, in order to investigate the possibility that different survey methodologies might identify different biodiversity patterns in habitat disturbance assessments, I investigate whether two different but commonly used survey methodologies used to assess amphibians, indicate the same or different responses of amphibian biodiversity to historic habitat change by people. The regenerating rainforest study site contained high levels of species richness; both in terms of alpha diversity found in nearby primary forest areas (87% ±3.5) and in terms of predicted primary forest diversity from the region (83% ±6.7). This included 89% (39 out of 44) of the species of high conservation concern predicted for the Manu region. Faunal species richness in once completely cleared regenerating forest was on average 13% (±9.8) lower than historically selectively logged forest. The presence of the small unmarked road significantly altered levels of faunal biodiversity for three taxa, up to and potentially beyond 350m into the forest interior. Most notably, the impact on biodiversity extended to at least 32% of the whole reserve area. The assessment of butterflies across strata showed that different vertical zones within the same rainforest responded differently in areas with different historic human disturbance. A comparison between forest regenerating after selective logging and forest regenerating after complete clearance, showed that there was a 17% greater reduction in canopy species richness in the historically cleared forest compared with the terrestrial community. Comparing arboreal camera traps with traditional ground-based techniques suggests that camera traps are an effective tool for inventorying secretive arboreal rainforest mammal communities and detect a higher number of cryptic species. Finally, the two survey methodologies used to assess amphibian communities identified contrasting biodiversity patterns in a human modified rainforest; one indicated biodiversity differences between forests with different human disturbance histories, whereas the other suggested no differences between forest disturbance types. Overall, in this thesis I find that the conservation and biodiversity value of regenerating and human disturbed tropical forest can potentially contribute to rainforest biodiversity conservation, particularly in the best of circumstances. I also highlight the importance of utilising appropriate study methodologies that to investigate these three-dimensional habitats, and contribute to the development of methodologies to do so. However, care should be taken when using different survey methodologies, which can provide contrasting biodiversity patterns in response to human disturbance.

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George Keith, fourth Earl Marischal is a case study of long-term, quietly successful and stable lordship through the reign of James VI. Marischal’s life provides a wholly underrepresented perspective on this era, where the study of rebellious and notorious characters has dominated. He is also a counter-example to the notion of a general crisis among the European nobility, at least in the Scottish context, as well as to the notion of a ‘conservative’ or ‘Catholic’ north east. In 1580 George inherited the richest earldom in Scotland, with a geographical extent stretching along the east coast from Caithness to East Lothian. His family came to be this wealthy as a long term consequence of the Battle of Flodden (1513) where a branch of the family, the Inverugie Keiths had been killed. The heiress of this branch was married to the third earl and this had concentrated a large number of lands, and consequently wealth, in the hands of the earls. This had, however, also significantly decreased the number of members and hence power of the Keith kindred. The third earl’s conversion to Protestantism in 1544 and later his adherence to the King’s Party during the Marian Civil War forced the Keiths into direct confrontation with their neighbours in the north east, the Gordons (led by the Earls of Huntly), a Catholic family and supporters of the Queen’s Party. Although this feud was settled for a time at the end of the war, the political turmoil caused by a succession of short-lived factional regimes in the early part of the personal reign of James VI (c.1578-1585) led the new (fourth) Earl Marischal into direct confrontation with the new (sixth) Earl of Huntly. Marischal was outclassed, outmanoeuvred and outgunned at both court and in the locality in this feud, suffering considerably. However, Huntly’s over-ambition in wider court politics meant that Marischal was able to join various coalitions against his rival, until Huntly was exiled in 1595. Marischal also came into conflict briefly with Chancellor John Maitland of Thirlestane as a consequence of Marischal’s diplomatic mission to Denmark in 1589-1590, but was again outmatched politically and briefly imprisoned. Both of these feuds reveal Marischal to be relatively cautious and reactionary, and both reveal the limitations of his power. Elsewhere, the study of Marischal’s activities in the centre of Scottish politics reveal him to be unambitious. He was ready to serve King James, the two men having a healthy working relationship, but Marischal showed no ambition as a courtier, to woo the king’s favour or patronage, instead delegating interaction with the monarch to his kinsmen. Likewise, in government, Marischal rarely attended any of the committees he was entitled to attend, such as the Privy Council, although he did keep a keen eye on the land market and the business conducted under the Great Seal. Although personally devout and a committed Protestant, the study of Marischal’s interaction with the national Kirk and the parishes of which he was patron reveal that he was at times a negligent patron and exercised his right of ministerial presentation as lordly, not godly patronage. The notion of a ‘conservative North East’ is, however, rejected. Where Marischal was politically weak at court and weak in terms of force in the locality, we see him pursuing sideways approaches to dealing with this. Thus he was keen to build up his general influence in the north and in particular with the burgh of Aberdeen (one result of this being the creation of Marischal College in 1593), pursued disputes through increasing use of legal methods rather than bloodfeud (thus exploiting his wealth and compensating for his relative lack of force) and developed a sophisticated system of maritime infrastructure, ultimately expressed through the creating of the burghs of Peterhead and Stonehaven. Although his close family caused him a number of problems over his lifetime, he was able to pass on a stable and enlarged lordship to his son in 1623.