| 1. |
- Mendoza, J. A., et al.
(författare)
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Assessment of groundwater vulnerability in the Rio Artiguas basin, Nicaragua
- 2006
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Ingår i: Environmental Geology. - : Springer Science and Business Media LLC. - 0943-0105 .- 1432-0495. ; 50:4, s. 569-580
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Tidskriftsartikel (refereegranskat)abstract
- The Rio Artiguas basin in central Nicaragua shows a distinctive case of environmental deterioration due to anthropogenic activities. Heavy metals used in gold mining and other wastes are continuously released into the rivers, representing a threat to the water quality. This article aims to evaluate the groundwater intrinsic vulnerability in the Rio Artiguas basin and to provide information for sustainable use of water resources. The DRASTIC and GOD methods were used to analyse the relative pollution potential within the basin. DRASTIC was modified to include the degree of influence that geological structures have on the vulnerability. Moderate vulnerability areas cover most of the basin along stream valleys and lowlands, increasing downstream in the basin. The resulting vulnerability maps show that the limited groundwater resources are susceptible to surface water pollution as high vulnerability areas converge along the river valleys.
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| 2. |
- Corriols, Marvin, et al.
(författare)
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Geophysical characterization of the Leon-Chinandega aquifer, Nicaragua
- 2008
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Ingår i: Hydrogeology Journal. - : Springer Science and Business Media LLC. - 1431-2174 .- 1435-0157. ; 16:2, s. 349-362
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Tidskriftsartikel (refereegranskat)abstract
- Electrical geophysical surveys in the mode of vertical electrical soundings (VES) and continuous vertical electrical soundings (CVES) were conducted in the Leon-Chinandega plains, northwestern Nicaragua, in order to obtain detailed information about the geometry of the different hydrogeological layers in the aquifer and depth to the basement. A total of 51 VES were carried out within the plains. The results show a complex structure towards the north east of the area, and the southwestern part of the plains presents a smoother stratification. The geoelectrical measurements and borehole information indicate that the basement topography is characterized by hills and deep valleys with highly variable basement depths. Fifty CVES where done in a smaller area in the center of the plain. The resistivity data yielded considerable information revealing the existence of two main geo-electrical units. The combined interpretation of geological and geophysical data shows an environment typical of sedimentary volcanic coastal plains. The information collected during this investigation provides valuable data for estimating the fresh-water resources of the Leon-Chinandega aquifer system and for development of a groundwater management plan.
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| 3. |
- Mendoza, J. A., et al.
(författare)
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Hydrogeological and hydrochemical features of an area polluted by heavy metals in central Nicaragua
- 2006
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Ingår i: Hydrogeology Journal. - : Springer Science and Business Media LLC. - 1431-2174 .- 1435-0157. ; 14:5, s. 777-784
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Tidskriftsartikel (refereegranskat)abstract
- Geophysical and hydrochemical surveys were used to investigate the hydrogeological conditions in one of the Rio Sucio microbasins, in central Nicaragua. Zones of vertical structures (i.e. fractures and quartz veins) and weathering were mapped using Continuous Vertical Electrical Soundings (CVES), as such zones are of major importance for groundwater transport. Water from the springs was analysed to determine concentrations of major ions and heavy metals. Low ion concentrations and 180 analyses indicate that the springs occur close to their recharge areas and there is a relatively rapid groundwater circulation. Mercury (Hg) content in the springs was low, while comparatively high amounts of lead (Pb) were found. The results presented here demonstrate the important function of weathering and tectonics in the occurrence of groundwater systems in the basin. Hg and Pb found in the springs' water reveal the existence of an increase in pollution sources disseminating in the area. More than 100 years of using mercury in the gold-mining industry and releasing wastes into rivers has affected water quality and ecosystems. Further investigations are needed in this area to determine the groundwater vulnerability to this pollution as this resource may be needed in the future.
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| 4. |
- Mendoza, Jose Alfredo, et al.
(författare)
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Aquifer interactions with a polluted mountain river of Nicaragua
- 2008
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Ingår i: Hydrological Processes. - : Wiley. - 1099-1085 .- 0885-6087. ; 22:13, s. 2264-2273
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Tidskriftsartikel (refereegranskat)abstract
- The interactions between a stream and nearby shallow aquifers were investigated in a mountain basin being polluted by mercury released during mining in central Nicaragua. Hourly data series of water levels and temperatures were analysed using cross-correlation. Resistivity imaging was used to map the subsurface and to complement the hydrological data interpretation. The results show the complex hydrogeological conditions that characterize the region, with weathering and fractured rock as main contributors to groundwater transport. The resistivity images suggest the presence of two vertical dykes perpendicular to the stream, and zones rich in clay. The data series indicate a rapid response from the aquifers to recharge events, followed by immediate discharge on a yearly basis. Furthermore, alternating periods of stream infiltration and aquifer discharge were identified. This work demonstrates that surface water pollution is a threat to groundwater quality in the area.
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| 5. |
- Mendoza, Alfredo
(författare)
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Groundwater occurrence and risk of pollution in a mountain watershed of Nicaragua
- 2006
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Doktorsavhandling (övrigt vetenskapligt/konstnärligt)abstract
- Hydrogeological and geophysical methods were applied in the Río Artiguas watershed, a mountain basin located in central Nicaragua. This area is under environmental stress from anthropogenic activities like gold mining using mercury and waste disposal into the streams. The aim of this work was to characterise the hydrogeological conditions in the basin with emphasis on understanding the possible connections between streams and groundwater. It was also important to evaluate the vulnerability and risk of groundwater pollution. Hydrogeological mapping, resistivity imaging, hydrological measurements and hydrochemical surveys were combined to meet the aims of the work. The hydrogeological characterisation permitted identification of a) recharge areas, b) geological units that contribute to the formation of the groundwater system and c) a mechanism of discharge through springs and streams. The geophysical surveys allowed mapping the extension of weathering and tectonic features with hydrogeological significance, e.g. faults, dykes and fractures. A total of 99 perennial springs were documented and classified according to their mechanism of formation. Isotopic data indicate that the recharge occurs very close to the sites where the springs are formed. This is also supported by the relatively low ion concentrations found in the water of the springs. The weathering layers together with fractures and dykes form shallow aquifers that commonly discharge in a spring or along the streams. The high precipitation regime is an immediate source of water to the system, and in conjunction with the geology and steep topography it generates a constant and rapid circulation of water from recharge areas to discharge zones. The natural implication of this hydrogeological framework is that the formation of large or regional flows is not evident at the current state of knowledge. The same factors that influence groundwater occurrence are to some extent responsible for the degree of groundwater vulnerability to pollution. The vulnerable areas are situated along the steep valleys of the basin, where the interactions between subsurface and surface water can facilitate the spreading of pollutants. Since the pollution sources are located near the streams the risk of groundwater pollution is concentrated there. The pollutants disposed into the streams are rapidly removed by the river flow, which has a high contribution from precipitation. The pollutants are then transported far away from the sources. The urgent need to end the pollution of Río Artiguas is obvious. The tools to prevent further deterioration are not only to be found in the hydro geosciences and mining technology sphere, but they are also located in the socio?political arena. In this respect, the research presented in this thesis will gain importance as it reaches and informs local decision makers about the vulnerability and risks of pollution that the current anthropogenic activities represent for the groundwater resources.
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| 6. |
- Stein, Alfredo
(författare)
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Urban poverty, social exclusion and social housing finance. The case of PRODEL in Nicaragua
- 2010
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Doktorsavhandling (övrigt vetenskapligt/konstnärligt)abstract
- The purpose of the thesis is to further understand key conceptual and operational challenges that international aid donors, and public and private institutions, face while designing and implementing alternative forms of social housing finance which aim to be inclusive for the urban poor. Based on an in-depth study of the work of the Foundation for the Promotion of Local Development (PRODEL) in three cities in Nicaragua during a period of 15 years, the thesis tries to answer three research questions: What are the constraints the urban poor face in financing the incremental way they build their individual housing and collective assets? Why does housing microfinance not always enhance inclusion of the urban poor? How does the tension between the goal of achieving financial sustainability and increasing financial inclusion affect the policy of international donors and governments, and the practice of local financial institutions? To answer these questions, the thesis adopts a realist approach as well as a critical case study method as used in disciplines such as political science and history to explain the trends and complexities of the phenomena investigated, and formulates an argument in the form of a proposition: if financial exclusion occurs in PRODEL it might also occur elsewhere. Qualitative and quantitative research techniques helped to assess the perceptions of stakeholders that participated in PRODEL’s small and repetitive housing improvement loans and in the co-financing mechanism for basic infrastructure components. The thesis shows significant improvements in the living conditions of the urban poor as result of PRODEL’s investments. Although income levels and external political and macroeconomic constraints are significant factors, understanding the different assets that the urban poor possess, has a critical effect on the ways individual households are included in micro-lending schemes. Interviewees considered that their poverty situation related more to the conditions prevailing in their neighbourhood and city than to their household income levels. Family breakdown; lack of education; insecurity; the lack of opportunities in the city; or a permanent sense of helplessness given the recurrent political and economic crises were more important than their monetary consumption levels. Increased self-esteem from being included in financial schemes that improved their homes and neighbourhood was equally important. Interviewees expressed that it was not the lack of income that pre-empted their participation in housing loan schemes, but the lack of reliable information; their fear of the unknown; and the lack of knowledge on how microfinance institutions operated. Additionally, the thesis shows that financial inclusion increases when accountable and transparent participatory methods of negotiation and co-financing mechanisms between urban poor communities and local governments to improve the provision of infrastructure and basic services are in place. Finally, the thesis offers new insights on how the concept of financial sustainability narrowed the approach and policy of international aid donors and governments, and the practice of financial institutions, when seeking financial inclusion. These findings shed light on the theoretical and practical limits of up-scaling housing improvement schemes as part of wider urban poverty reduction strategies in low-income countries such as Nicaragua.
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| 7. |
- Athanasiadou, Maria, et al.
(författare)
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Polybrominated diphenyl ethers (PBDEs) and bioaccumulative hydroxylated PBDE metabolites in young humans from Managua, Nicaragua.
- 2008
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Ingår i: Environ Health Perspect. - : Environmental Health Perspectives. - 0091-6765 .- 1552-9924. ; 116:3, s. 400-8
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Tidskriftsartikel (refereegranskat)abstract
- OBJECTIVE: Our aim was to investigate exposure to polybrominated diphenyl ethers (PBDEs) in a young urban population in a developing country, with focus on potentially highly exposed children working informally as scrap scavengers at a large municipal waste disposal site. We also set out to investigate whether hydroxylated metabolites, which not hitherto have been found retained in humans, could be detected. METHODS: We assessed PBDEs in pooled serum samples obtained in 2002 from children 11-15 years of age, working and sometimes also living at the municipal waste disposal site in Managua, and in nonworking urban children. The influence of fish consumption was evaluated in the children and in groups of women 15-44 years of age who differed markedly in their fish consumption. Hydroxylated PBDEs were assessed as their methoxylated derivates. The chemical analyses were performed by gas chromatography/mass spectrometry, using authentic reference substances. RESULTS: The children living and working at the waste disposal site showed very high levels of medium brominated diphenyl ethers. The levels observed in the referent children were comparable to contemporary observations in the United States. The exposure pattern was consistent with dust being the dominating source. The children with the highest PBDE levels also had the highest levels of hydroxylated metabolites. CONCLUSIONS: Unexpectedly, very high levels of PBDEs were found in children from an urban area in a developing country. Also, for the first time, hydroxylated PBDE metabolites were found to bioaccumulate in human serum.
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| 8. |
- Kindblad, Christopher
(författare)
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Gift and Exchange in the Reciprocal Regime of the Miskito on the Atlantic Coast of Nicaragua, 20th Century
- 2001
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Doktorsavhandling (övrigt vetenskapligt/konstnärligt)abstract
- This dissertation is a historical-comparative analysis of a conflict that has developed in the economic system of the Miskito in the 20th century, concerning the use of common property resources. The study is based on empirical material collected in a Miskito/Creole village on the Atlantic Coast of Nicaragua in the 1990s. During the enclave period (1860-1960) Miskito men earned money as wage labourers at foreign companies (lumber, mining and banana plantations), and sent home money and purchased goods to women, who worked in subsistence agriculture. At this time the communal resources were reserved mainly for subsistence and food gifts. This permitted a symbolic transformation of money and purchased goods, which were distributed in a wider network of kin-related women. There was a relatively stable coexistence of short-term exchange and long-term gift, which is referred to as a reciprocal regime. However, the transition to the commercial period (1960-) resulted in a commercial exploitation of communal resources, which seriously started to compete with subsistence and the custom of food gifts in the 1970s. A contradiction developed between short-term exchange and long-term gift, which stems from a double and contradictory coding of communal resources. This development was interrupted during the 1980s - the decade of the Sandinist revolution - but continued in the 1990s, although new aspects were added due to increasing population pressure, external exploitation and few opportunities for wage labour. In spite of instabilities in the reciprocal regime, the analysis suggests that there could be a conflictual coexistence of gift and exchange, which is potentially creative for the future.
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| 9. |
- Rivera, Claudia
(författare)
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Integrating Climate Change Adaptation into Disaster Risk Reduction in Urban Contexts: Perceptions and Practice
- 2014
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Ingår i: PLoS Currents. - : Public Library of Science (PLoS). - 2157-3999. ; 6
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Tidskriftsartikel (refereegranskat)abstract
- This paper analyses the perceptions of disaster risk reduction (DRR) practitioners concerning the on-going integration of climate change adaptation (CCA) into their practices in urban contexts in Nicaragua. Understanding their perceptions is important as this will provide information on how this integration can be improved. Exploring the perceptions of practitioners in Nicaragua is important as the country has a long history of disasters, and practitioners have been developing the current DRR planning framework for more than a decade. The analysis is based on semi-structured interviews designed to collect information about practitioners’ understanding of: (a) CCA, (b) the current level of integration of CCA into DRR and urban planning, (c) the opportunities and constraints of this integration, and (d) the potential to adapt cities to climate change. The results revealed that practitioners’ perception is that the integration of CCA into their practice is at an early stage, and that they need to improve their understanding of CCA in terms of a development issue. Three main constraints on improved integration were identified: (a) a recognized lack of understanding of CCA, (b) insufficient guidance on how to integrate it, and (c) the limited opportunities to integrate it into urban planning due to a lack of instruments and capacity in this field. Three opportunities were also identified: (a) practitioners’ awareness of the need to integrate CCA into their practices, (b) the robust structure of the DRR planning framework in the country, which provides a suitable channel for facilitating integration, and (c) the fact that CCA is receiving more attention and financial and technical support from the international community.
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| 10. |
- Hernandez, Danilo, et al.
(författare)
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Respiratory Symptoms among Waste-Picking Child Laborers A Cross-Sectional Study
- 2010
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Ingår i: International Journal of Occupational and Environmental Health. - 1077-3525. ; 16:2, s. 124-135
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Tidskriftsartikel (refereegranskat)abstract
- This study evaluates respiratory symptoms, lung function, and exposure to airborne particles among waste-picking children. We enrolled 103 waste-picking children at a dump in Managua, Nicaragua and 103 children who do not pick waste. Exposure to airborne particles was assessed by area sampling. Health data were obtained from a questionnaire, clinical examination, and spirometry. Exposure effects were evaluated with multivariate regression analysis. Exposure to particles exceeded national and international standards. Wheezing among children was related to exposure status, with waste-picking children who are both "never highly exposed" and "ever highly exposed" having greater prevalence of wheezing compared to the children who do not pick waste. FEV1 among "ever highly exposed" waste-picking children with wheeze was 13% lower than non-waste-picking children with wheeze. Exposure to small particles was unacceptably high and associated with wheeze and decreased lung function.
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