20 resultados para Human impacts


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INTRODUCTION Out-migration from mountain areas is leaving behind half families and elderly to deal with managing the land alongside daily life challenges. A potential reduction of labour force as well as expertise on cropping practices, maintenance of terraces and irrigation canals, slope stabilization, grazing, forest and other land management practices are further challenged by changing climate conditions and increased environmental threats. An understanding of the resilience of managed land resources in order to enhance adaptation to environmental and socio-economic variability, and evidence of the impact of Sustainable Land Management (SLM) on the mitigation of environmental threats have so far not sufficiently been tackled. The study presented here aims to find out how land management in mountains is being affected by migration in the context of natural hazards and climate change in two study sites, namely Quillacollo District of Bolivia and Panchase area of Western Nepal, and which measures are needed to increase resilience of livelihoods and land management practices. The presentation includes draft results from first field work periods in both sites. A context of high vulnerability According to UNISDR, vulnerability is defined as “the characteristics and circumstances of a community, system or asset that make it susceptible to the damaging effects of a hazard”.Hazards are another threat affecting people’s livelihood in mountainous area. They can be either natural or human induced. Landslides, debris flow and flood are affecting peopleGood land management can significantly reduce occurrence of hazards. In the opposite bad land management or land abandonment can lead to negative consequences on the land, and thus again increase vulnerability of people’s livelihoods. METHODS The study integrates bio-physical and socio-economic data through a case study as well as a mapping approach. From the social sciences, well-tested participatory qualitative methodologies, typically used in Vulnerability and Capacity Analyses, such as semi-structured interviews with so-called ‘key informants’, transect walks, participatory risk and social resource mapping are applied. The bio-physical analysis of the current environmental conditions determining hazards and structural vulnerability are obtained from remote sensing analysis, field work studies, and GIS analysis The assessment of the consequences of migration in the area of origin is linked with a mapping and appraisal of land management practices (www.wocat.net, Schwilch et al., 2011). The WOCAT mapping tool (WOCAT/LADA/DESIRE 2008) allows capturing the major land management practices / technologies, their spread, effectiveness and impact within a selected area. Data drawn from a variety of sources are compiled and harmonised by a team of experts, consisting of land degradation and conservation specialists working in consultation with land users from various backgrounds. The specialists’ and land users’ knowledge is combined with existing datasets and documents (maps, GIS layers, high-resolution satellite images, etc.) in workshops that are designed to build consensus regarding the variables used to assess land degradation and SLM. This process is also referred to as participatory expert assessment or consensus mapping. The WOCAT mapping and SLM documentation methodologies are used together with participatory mapping and other socio-economic data collection (interviews, questionnaires, focus group discussions, expert consultation) to combine information about migration types and land management issues. GIS and other spatial visualization tools (e.g. Google maps) will help to represent and understand these links. FIRST RESULTS Nepal In Nepal, migration is a common strategy to improve the livelihoods. Migrants are mostly men and they migrate to other Asian countries, first to India and then to the Gulf countries. Only a few women are migrating abroad. Women migrate essentially to main Nepali cities when they can afford it. Remittances are used primarily for food and education; however they are hardly used for agricultural purposes. Besides traditional agriculture being maintained, only few new practices are emerging, such as vegetable farming or agroforestry. The land abandonment is a growing consequence of outmigration, resulting in the spreading of invasive species. However, most impacts of migration on land management are not yet clear. Moreover, education is a major concern for the respondents; they want their children having a better education and get better opportunities. Linked to this, unemployment is another major concern of the respondents, which in turn is “solved” through outmigration. Bolivia Migration is a common livelihood strategy in Bolivia. In the area of study, whole families are migrating downward to the cities of the valleys or to other departments of Bolivia, especially to Chapare (tropics) for the coca production and to Santa Cruz. Some young people are migrating abroad, mostly to Argentina. There are few remittances and if those are sent to the families in the mountain areas, then they are mainly used for agriculture purpose. The impacts of migration on land management practices are not clear although there are some important aspects to be underlined. The people who move downward are still using their land and coming back during part of the week to work on it. As a consequence of this multi-residency, there is a tendency to reduce land management work or to change the way the land is used. As in Nepal, education is a very important issue in this area. There is no secondary school, and only one community has a primary school. After the 6th grade students have therefore to go down into the valley towns to study. The lack of basic education is pushing more and more people to move down and to leave the mountains. CONCLUSIONS This study is on-going, more data have to be collected to clearly assess the impacts of out-migration on land management in mountain areas. The first results of the study allow us to present a few interesting findings. The two case studies are very different, however in both areas, young people are not staying anymore in the mountains and leave behind half families and elderly to manage the land. Additionally in both cases education is a major reason for moving out, even though the causes are not always the same. More specifically, in the case of Nepal, the use of remittances underlines the fact that investment in agriculture is not the first choice of a family. In the case of Bolivia, some interesting findings showed that people continue to work on their lands even if they move downward. The further steps of the study will help to explore these interesting issues in more detail. REFERENCES Schwilch G., Bestelmeyer B., Bunning S., Critchley W., Herrick J., Kellner K., Liniger H.P., Nachtergaele F., Ritsema C.J., Schuster B., Tabo R., van Lynden G., Winslow M. 2011. Experiences in Monitoring and Assessment of Sustainable Land Management. Land Degradation & Development 22 (2), 214-225. Doi 10.1002/ldr.1040 WOCAT/LADA/DESIRE 2008. A Questionnaire for Mapping Land Degradation and Sustainable Land Management. Liniger H.P., van Lynden G., Nachtergaele F., Schwilch G. (eds), Centre for Development and Environment, Institute of Geography, University of Berne, Berne

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The introduction and establishment of non-indigenous species through human activities often poses a major threat to natural biodiversity. In many parts of the world management efforts are therefore focused on their eradication. The environment of World Heritage sub-Antarctic Macquarie Island has been severely damaged by non-indigenous species including rabbits, rats and mice, introduced from the late AD 1800s. An extensive eradication programme is now underway which aims to remove all rabbits and rodents. To provide a long-term context for assessing the Island's pre-invasion state, invasion impacts, and to provide a baseline for monitoring its recovery, we undertook a palaeoecological study using proxies in a lake sediment core. Sedimentological and diatom analyses revealed an unproductive catchment and lake environment persisted for ca. 7100 years prior to the introduction of the invasive species. After ca. AD 1898, unprecedented and statistically significant environmental changes occurred. Lake sediment accumulation rates increased >100 times due to enhanced catchment inputs and within-lake production. Total carbon and total nitrogen contents of the sediments increased by a factor of four. The diatom flora became dominated by two previously rare species. The results strongly suggest a causal link between the anthropogenic introduction of rabbits and the changes identified in the lake sediments. This study provides an example of how palaeoecology may be used to determine baseline conditions prior to the introduction of non-indigenous species, quantify the timing and extent of changes, and help monitor the recovery of the ecosystem and natural biodiversity following successful non-indigenous species eradication programmes.

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This article analyses the impacts of four different bio-enterprise initiatives on agro-pastoral livelihoods and on improved natural resources management (NRM) in the drylands of Kenya. In this way it contributes to an area of rural development that is gaining increasing interest, but still has little empirical evidence. Data were collected through interviews, focus group discussions, informal discussions and the study of reports. One of the key findings of this article is that diversification into enterprises requires cooperation among the stakeholders with their varying experiences in development, NRM and business development. In addition to initial investments, such enterprises need sustained financial, as well as other support like capacity development to survive the market introduction phase. For such enterprises to defend their market niches, the quantity and quality of the product are critical. In addition to support in human, financial, social, physical and natural capital, mentoring is another crucial factor for success.

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Autophagy assures cellular homeostasis, and gains increasing importance in cancer, where it impacts on carcinogenesis, propagation of the malignant phenotype and development of resistance. To date, its tissue-based analysis by immunohistochemistry remains poorly standardized. Here we show the feasibility of specifically and reliably assessing the autophagy markers LC3B and p62 (SQSTM1) in formalin fixed and paraffin embedded human tissue by immunohistochemistry. Preceding functional experiments consisted of depleting LC3B and p62 in H1299 lung cancer cells with subsequent induction of autophagy. Western blot and immunofluorescence validated antibody specificity, knockdown efficiency and autophagy induction prior to fixation in formalin and embedding in paraffin. LC3B and p62 antibodies were validated on formalin fixed and paraffin embedded cell pellets of treated and control cells and finally applied on a tissue microarray with 80 human malignant and non-neoplastic lung and stomach formalin fixed and paraffin embedded tissue samples. Dot-like staining of various degrees was observed in cell pellets and 18/40 (LC3B) and 22/40 (p62) tumors, respectively. Seventeen tumors were double positive for LC3B and p62. P62 displayed additional significant cytoplasmic and nuclear staining of unknown significance. Interobserver-agreement for grading of staining intensities and patterns was substantial to excellent (kappa values 0.60 - 0.83). In summary, we present a specific and reliable IHC staining of LC3B and p62 on formalin fixed and paraffin embedded human tissue. Our presented protocol is designed to aid reliable investigation of dysregulated autophagy in solid tumors and may be used on large tissue collectives.

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Modern period long-term human and climatic impacts on a small mire in the Jura Mountains were assessed using testate amoebae, macrofossils and pollen. This multiproxy data analysis permitted detailed interpretations of local and regional environmental change and thus a partial disentanglement of the different variables that influence long-term mire development. From the Middle Ages until a.d. 1700 the mire vegetation was characterised by ferns, Caltha and Vaccinium, but then abruptly changed into the modern vegetation characterised by Cyperaceae, Potentilla and Sphagnum. The cause for this change was most probably deforestation, possibly enhanced by climatic cooling. A decrease in trampling intensity by domestic animals from a.d. 1950 onwards allowed Sphagnum growth and climatic warming in the a.d. 1980s and 1990s may have been responsible for considerable changes in the species composition. The mire investigated is an example of the rapid changes in mire vegetation and peat development that occurred throughout the central European mountain region during the past centuries as a result of changing climate and land-use practice. These processes are still active today and will determine the future development of high-altitude mires.