8 resultados para agricultural impacts
em CORA - Cork Open Research Archive - University College Cork - Ireland
Resumo:
A multi-disciplinary study was conducted to compare stands of ancient and secondary origin within a single wood, the Gearagh woodland, County Cork. These sites were compared with adjacent areas of grassland, which provided a reference for the former land-use (pasture) of the secondary woodland. A historical study confirmed that while the core of the Gearagh has been subject to minimal human interference, other sections have been cleared in the past for agricultural purposes. Investigations into soil structure and composition showed that soil properties in these secondary woodland areas were significantly altered by this past woodland clearance and conversion to agriculture, while the soil of the ancient woodland showed little signs of disturbance. The vegetation community also differed between the two woodland areas, partly due to altered environmental conditions. Many of the ancient woodland plant species were unable to form a persistent seed bank, while there was increased representation of species associated with more open-habitat conditions in the seed bank of the secondary woodland. While germination of woodland species was low in all sites, overall, seeds tended to germinate more successfully in the ancient woodland. The ancient woodland also provided a suitable habitat for many soil and ground detritivores, most notably enchytraeids, although earthworms were not abundant. Past agricultural use, however, changed the decomposer community considerably, with increased representation of earthworm species and a decline in the abundance of enchytraeids in the secondary stands. In conclusion, the legacies of historical agricultural activities can continue to significantly affect the structure and composition of present-day woodlands so that they may differ considerably from undisturbed ancient woodland stands, even within the same woodland. A greater understanding of the origin, development and ecological functioning of ancient woodlands should aid in determining future conservation and management requirements.
Resumo:
This study selected six geographically-similar villages with traditional and alternative cultivation methods (two groups of three, one traditional and two alternatives) in two counties of Henan Province, China—a representative area of the Huang-huai-hai Plain representing traditional rural China. Soil heavy metal concentrations, floral and faunal biodiversity, and socio-economic data were recorded. Heavy metal concentrations of surface soils from three sites in each village were analysed using Inductively Coupled Plasma Mass Spectrometry (ICP-MS, chromium, nickel, copper, cadmium, and lead) and Atomic Absorption Spectrophotometer (AAS, zinc). The floral biodiversity of four land-use types was recorded following the Braun-Blanquet coverage-abundance method using 0.5×0.5m quadrats. The faunal biodiversity of two representative farmland plots was recorded using 0.3×0.3m quadrats at four 0.1m layers. The socio-economic data were recorded through face-to-face interviews of one hundred randomly selected households at each village. Results demonstrate different cultivation methods lead to different impact on above variables. Traditional cultivation led to lower heavy metal concentrations; both alternative managements were associated with massive agrochemical input causing heavy metal pollution in farmlands. Floral distribution was significantly affected by village factors. Diverse cultivation supported high floral biodiversity through multi-scale heterogeneous landscapes containing niches and habitats. Faunal distribution was also significantly affected by village factor nested within soil depth. Different faunal groups responded differently, with Acari being taxonomically diverse and Collembola high in densities. Increase in manual labour and crop number in villages using alternative cultivation may positively affect biodiversity. The results point to the conservation potential of diverse cultivation methods in traditional rural China and other regions under social and political reforms, where traditional agriculture is changing to unified, large-scale mechanized agriculture. This study serves as a baseline for conservation in small-holding agricultural areas of China, and points to the necessity of further studies at larger and longer scales.
Resumo:
This thesis aimed to provide an understanding of how human-induced changes in the economic sectors of agriculture and transport affect carabid diversity, potential carabidmediated biocontrol and predator-pest interactions. The research involved both observational and manipulative laboratory and field-based studies. Observational research consisted of two large-scale investigations of (1) the impact of Miscanthus and oilseed rape production (n=45) and (2) the impact of horticultural and ecological based landscaping of roadside verges (n=64). This research is the first record of carabid diversity, potential biocontrol and community assemblage with respect to bioenergy crop production and roadside landscaping in an Irish context and it is also an important addition to the limited knowledge of carabid populations in these ecosystems internationally. Manipulative work involved the examination of the role predator identity, diversity and biomass play in the suppression of pollen beetle larvae (an economically damaging insect pest of oilseed rape in Europe), using a novel experimental design called ‘simplex’. To complement this research, an additional field study on the impact of low and high oilseed rape pesticide management on carabid species richness and abundance, and crop yield, was also conducted. This research is a great contribution to the existing understanding of what constitutes the important components of predator biodiversity and expands the knowledge of the usefulness of carabid predators in the context of pollen beetle larvae control. In particular, the work shows that the abundance or biomass of beetles has an effect that is far larger than the effect of diversity on the capacity of beetles to consume prey. In turn, the field study showed that pesticide applications had little impact on yield, or carabid richness, but that carabid abundance/biomass declined drastically. The work provides compelling evidence that management practices erode the useful components of biodiversity that are essential for the delivery of biocontrol services.
Resumo:
The flower industry has a reputation for heavy usage of toxic chemicals and polluting the environment, enormous consumption of water, and poor working condition and low wage level in various parts of the world. It is unfortunate that this industry is adamant to change and repeating the same mistakes in Ethiopia. Because of this, - there is a growing concern among the general public and the international community about sustainability of the Ethiopian flower industry. Consequently, working conditions in the flower industry, impacts of wage income on the livelihoods of employees, coping strategies of low wage flower farm workers, impacts of flower farms on the livelihoods of local people and environmental pollution and conflict, were analysed. Both qualitative and quantitative research methods were employed. Four quantitative data sets: labour practice, employees’ income and expenditure, displaced household, and flower grower views survey were collected between 2010 and 2012. Robust regression to identify the determinants of wage levels, and Multinomial logit to identify the determinants of coping strategies of flower farm workers and displaced households were employed. The findings show the working conditions in flower farms are characterized by low wages, job insecurity and frequent violation of employees’ rights, and poor safety measures. To ensure survival of their family, land dispossessed households adopt a wide range of strategies including reduction in food consumption, sharing oxen, renting land, share cropping, and shifting staple food crops. Most experienced scarcity of water resources, lack of grazing areas, death of herds and reduced numbers of livestock due to water source pollution. Despite the Ethiopian government investment in attracting and creating conducive environment for investors, not much was accomplished when it comes to enforcing labour laws and environmental policies. Flower farm expansion in Ethiopia, as it is now, can be viewed as part of the global land and water grab and is not all inclusive and sustainable. Several recommendations are made to improve working conditions, maximize the benefits of flower industry to the society, and to the country at large.
Resumo:
Following international trends victims of crime in Ireland have increasingly become a source of political, policy and to a lesser extent academic concern. Although it is assumed that the Irish victims’ rights movement is having a profound impact on the criminal justice system there are very few studies addressing this assumption or the genesis of the Irish movement. At the time a victims’ rights movement was established in Ireland there were movements already established in the U.S. and Britain. To determine which model Ireland followed, if any, in establishing its movement a comparative analysis of the emergence of the victims’ rights movements in these three common law jurisdictions was undertaken. This research examines possible victim policy transfer to test the transfer route perception that the victims’ movement began in the U.S., was transferred into Britain and then onto Ireland. At the same time that the victims’ rights movements were emerging in the U.S., Britain and Ireland, and asserting pressure on their national governments for beneficial changes for victims of crime, international organisations such as the U.N. and Council of Europe were being pressured by victims’ rights groups into introducing victim centered instruments of guidance and best practice for member states. Eventually the E.U. became involved and enacted a binding instrument in 2001. These victim centered instruments provide legal and service provision rights to Irish victims of crime, but they do not generate much academic interest. This research, in addition to providing a detailed account of the victim centered instruments, analyses the jurisprudence of the European Court of Human Rights, and identifies and analyses the primary victim centered statutory modifications and case law in Ireland over the past three decades. Lastly, the current law and practices in Ireland are evaluated against Ireland’s obligations under international and E.U. law.
Resumo:
Ireland and Britain were once covered in natural forest, but extensive anthropogenic deforestation reduced forest cover to less than 1% and 5 %, respectively, by the beginning of the 20th century. Large-scale afforestation has since increased the level of forest cover to 11% in Ireland and 12% in Britain, with the majority of planted forests comprising small monoculture plantations, many of which are of non - native conifer tree species. At present the forest cover of Ireland and Britain generally consists of small areas of remnant semi-natural woodland and pockets of these plantation forests within a predominantly agricultural landscape. Invertebrates comprise a large proportion of the biodiversity found within forested habitats. In particular, spiders and carabid beetles play an important role in food webs as both predators and prey and respond to small-scale changes in habitat structure, meaning they are particularly sensitive to forest management. Hoverflies play an important role in control and pollination and have been successfully used as indicators of habitat disturbance and quality. This research addressed a number of topics pertinent to the forest types present in the contemporary Irish and British landscapes and aimed to investigate the invertebrate diversity of these forests. Spiders and carabid beetles were sampled using pitfall trapping and hoverflies were sampled using Malaise net trapping. Topics included the impacts of afforestation, the importance of open space, the choice of tree species, and the use of indicators for biodiversity assessment, as well as rare native woodlands and the effect of grazing on invertebrate diversity. The results are discussed and evidence-based recommendations are made for forest policy and management to protect and enhance invertebrate biodiversity in order to promote sustainable forest management in Ireland and Britain.
Resumo:
Little is known about the biology of the softshell clam in Europe, despite it being identified as a potential species to culture for food in the future. Monthly samples of the softshell clam, Mya arenaria, were collected intertidally from Co. Wexford, Ireland, over a period of sixteen months. The mean weight of sampled individuals was 7 4 ± 4 . 9 g and mean length was 8 . 2 ± 0 . 2 cm. Histological examination revealed a female-to-male ratio of 1 : 1.15. In 2010, M. arenaria at this site matured over the summer months, with both sexes either ripe or spawning by August. A single spawning event was recorded in 2010, completed by November. Two unusually cold winters, followed by a warmer-than-average spring, appear to have affected M. arenaria gametogenesis in this area, potentially affecting the time of spawning, fertilisation success, and recruitment of this species. No hermaphrodites were observed in the samples collected, nor were any pathogens observed. Timing of development and spawning is compared with the coasts of eastern North America and with other European coasts.
Resumo:
The climatic development of the Mid to Late Quaternary (last 400,000 years) is characterised by fluctuation between glacial and interglacial periods leading to the present interglacial, the Holocene. In comparison to preceding periods it was believed the Holocene represented a time of relative climatic stability. However, recent work has shown that the Holocene can be divided into cooler periods such as the Little Ice Age alternating with time intervals where climatic conditions ameliorated i.e. Medieval Warm Period, Holocene Thermal Optimum and the present Modern Optimum. In addition, the Holocene is recognised as a period with increasing anthropogenic influence on the environment. Onshore records recording glacial/interglacial cycles as well as anthropogenic effects are limited. However, sites of sediment accumulation on the shallow continental shelf offer the potential to reconstruct these events. Such sites include tunnel valleys and low energy, depositional settings. In this study we interrogated the sediment stratigraphy at such sites in the North Sea and Irish Sea using traditional techniques, as well as novel applications of geotechnical data, to reconstruct the palaeoenvironmental record. Within the German North Sea sector a combination of core, seismic and in-situ Cone Penetration Testing (CPT) data was used to identify sedimentary units, place them within a morphological context, relate them to glacial or interglacial periods stratigraphically, and correlate them across the German North Sea. Subsequently, we were able to revise the Mid to Late Quaternary stratigraphy for the North Sea using this new and novel data. Similarly, Holocene environmental changes were investigated within the Irish Sea at a depositional site with active anthropogenic influence. The methods used included analyses on grain-size distribution, foraminifera, gamma spectrometry, AMS 14C and physical core logging. The investigation revealed a strong fluctuating climatic signal early in the areas history before anthropogenic influence affects the record through trawling.