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Julie Cupples 《Singapore journal of tropical geography》2004,25(3):343-357
El Hatillo is a rural community in the Sébaco valley in Nicaragua, which suffers from an eroding resource base, high levels of poverty and malnutrition, and a high susceptibility to hazards. Structural adjustment policies have been devastating for small and subsistence farmers and have increased the level of economic, social and environmental marginalisation in rural Nicaragua. This paper explores initiatives to promote sustainable development in Nicaragua in the context of structural adjustment and environmental degradation. Drawing on qualitative research conducted in El Hatillo, it outlines the ways in which women in this community are attempting to address the multiple challenges of rural poverty and environmental risk and considers the potential of these strategies for gender equality. 相似文献
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K. Garofalo F. Tassi O. Vaselli A. Delgado-Huertas D. Tedesco M. Frische T. H. Hansteen R. J. Poreda W. Strauch 《Bulletin of Volcanology》2007,69(7):785-795
Mombacho is a deeply dissected volcano belonging to the Quaternary volcanic chain of Nicaragua. The southern, historic collapse
crater (El Crater) currently hosts a fumarolic field with a maximum temperature of 121°C. Chemical and isotopic data from
five gas-sampling field campaigns carried out in 2002, 2003 and 2005 highlight the presence of high-temperature gas components
(e.g. SO2, HCl and HF), which indicate a significant contribution of juvenile magmatic fluids to the hydrothermal system feeding the
gas discharges. This is strongly supported by the mantle-derived helium and carbon isotopic signatures, although the latter
is partly masked by either a sedimentary subduction-related or a shallow carbonate component. The observed chemical and isotopic
composition of the Mombacho fluids seems to indicate that this volcanic system, although it has not experienced eruptive events
during the last centuries, can be considered active and possibly dangerous, in agreement with the geophysical data recorded
in the region. Systematic geochemical monitoring of the fumarolic gas discharges, coupled with a seismic and ground deformation
network, is highly recommended in order to monitor a possible new eruptive phase. 相似文献
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《Geoforum》2015
As Payments for Ecosystem Services (PES) continues to gain attention as a policy tool for securing efficient and effective environmental governance, a rising tide of criticism warns of the potentially detrimental social–ecological consequences of nature commodification and ‘green neoliberalism’. These concerns are also expressed at international policy fora, where the market rhetoric has met with political resistance from countries belonging to the ‘Bolivarian Alliance for the Peoples of Our America’ (ALBA). But despite this ideological opposition, some ALBA countries are increasingly integrating PES into their environmental policies. In this article we consider the reasons underlying this apparent contradiction and relate it to the notion of ‘epistemic circulation’. On the basis of a study on the evolution of PES-thinking in Nicaragua (an ALBA member) and a reassessment of the supposed ‘success’ of an influential pilot project, we shed light on the forces driving the adoption of particular PES modes and contextualise practical difficulties to endorsing more critical approaches to the tool. Instead of either ideologically rejecting PES as a neoliberal evil or embracing it uncritically as the new panacea, we argue that it is precisely through the socio-political processes surrounding environmental governance debates that the application of PES is shaped. In practice, it may either contribute to an imposed and dispossessing form of capitalism, or tend towards a more negotiated and socio-culturally embedded version of it. Only through its reconceptualisation based on political–cultural primacy rather than market-fetishism can PES achieve its true potential within a broader strategy towards improved environmental governance. 相似文献
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Hans-Ulrich Schmincke Steffen Kutterolf Wendy Perez Juanita Rausch Armin Freundt Wilfried Strauch 《Bulletin of Volcanology》2009,71(5):479-493
We present the stratigraphy, lithology, volcanology, and age of the Acahualinca section in Managua, including a famous footprint
layer exposed in two museum pits. The ca. 4-m-high walls of the main northern pit (Pit I) expose excellent cross sections
of Late Holocene volcaniclastic deposits in northern Managua. We have subdivided the section into six lithostratigraphic units,
some of which we correlate to Late Holocene eruptions. Unit I (1.2 m thick), chiefly of hydroclastic origin, begins with the
footprint layer. The bulk is dominated by mostly massive basaltic-andesitic tephra layers, interpreted to represent separate
pulses of a basically phreatomagmatic eruptive episode. We correlate these deposits based on compositional and stratigraphic
evidence to the Masaya Triple Layer erupted at Masaya volcano ca. 2,120 ± 120 a B.P.. The eruption occurred during the dry
season. A major erosional channel unconformity up to 1 m deep in the western half of Pit I separates Units II and I. Unit
II begins with basal dacitic pumice lapilli up to 10 cm thick overlain by a massive to bedded fine-grained dacitic tuff including
a layer of accretionary lapilli and pockets of well-rounded pumice lapilli. Angular nonvesicular glass shards are interpreted
to represent hydroclastic fragmentation. The dacitic tephra is correlated unequivocally with the ca. 1.9-ka-Plinian dacitic
Chiltepe eruption. Unit III, a lithified basaltic-andesitic deposit up to 50 cm thick and extremely rich in branch molds and
excellent leaf impressions, is correlated with the Masaya Tuff erupted ca. 1.8 ka ago. Unit IV, a reworked massive basaltic-andesitic
deposit, rich in brown tuff clasts and well bedded and cross bedded in the northwestern corner of Pit I, cuts erosionally
down as far as Unit I. A poorly defined, pale brown mass flow deposit up to 1 m thick (Unit V) is overlain by 1–1.5 m of dominantly
reworked, chiefly basaltic tephra topped by soil (Unit VI). A major erosional channel carved chiefly between deposition of
Units II and I may have existed as a shallow drainage channel even prior to deposition of the footprint layer. The swath of
the footprints is oriented NNW, roughly parallel to, and just east of, the axis of the channel. The interpretation of the
footprint layer as the initial product of a powerful eruption at Masaya volcano followed without erosional breaks by additional
layers of the same eruptive phase is strong evidence that the group of 15 or 16 people tried to escape from an eruption. 相似文献
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Electrical geophysical surveys in the mode of vertical electrical soundings (VES) and continuous vertical electrical soundings (CVES) were conducted in the León-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 León-Chinandega aquifer system and for development of a groundwater management plan. 相似文献
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Source characteristics of the 1992 Nicaragua tsunami earthquake inferred from teleseismic body waves
We analyzed the broadband body waves of the 1992 Nicaragua earthquake to determine the nature of rupture. The rupture propagation was represented by the distribution of point sources with moment-rate functions at 9 grid points with uniform spacing of 20 km along the fault strike. The moment-rate functions were then parameterized, and the parameters were determined with the least squares method with some constraints. The centroid times of the individual moment-rate functions indicate slow and smooth rupture propagation at a velocity of 1.5 km/s toward NW and 1.0 km/s toward SE. Including a small initial break which precedes the main rupture by about 10 s, we obtained a total source duration of 110 s. The total seismic moment isM
o
=3.4×1020 Nm, which is consistent with the value determined from long-period surface waves,M
o
=3.7×1020 Nm. The average rise time of dislocation is determined to be 10 s. The major moment release occurred along a fault length of 160 km. With the assumption of a fault widthW=50 km, we obtained the dislocationD=1.3 m. From andD the dislocation velocity isD=D/0.1 m/s, significantly smaller than the typical value for ordinary earthquakes. The stress drop =1.1 MPa is also less than the typical value for subduction zone earthquakes by a factor of 2–3. On the other hand, the apparent stress defined by 2E
s
/M
o
, where andE
s
are respectively the rigidity and the seismic wave energy, is 0.037 MPa, more than an order of magnitude smaller than . The Nicaragua tsunami earthquake is characterized by the following three properties: 1) slow rupture propagation; 2) smooth rupture; 3) slow dislocation motion. 相似文献
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Sergio Espinosa 《Natural Hazards》1996,13(2):179-202
A probabilistic macroseismic hazard assessment has been done for Nicaragua. For this, the most complete catalogue for Central America, compiled by NORSAR in Norway has been used. In this catalogue, empirical intensity attenuation relations were found. Using these empirical relations, magnitudes were changed to epicentral intensities expected in sites where no intensities had been reported. The calculated intensities from a polygon surrounding Nicaragua were used to assess the macroseismic hazard in the region. For the whole polygon, the cumulative intensity frequency was calculated resulting in a b-value of 0.60 for an intensity interval of V–IX. The time completeness was also studied indicating that, for strong events causing higher intensities (I
0 VII), the catalogue is complete for events that have been recorded since 1840. The whole polygon was cut into independent seismotectonic regions where the statistical procedure (intensity frequency and time completeness) was done. 相似文献
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Despite persistent images to the contrary, most fieldworkers are accompanied. Yet, there has been limited discussion on the nature of accompanied fieldwork, particularly by geographers. Drawing on our experiences in three countries in the tropics, we discuss the dynamics of being accompanied in “the field” by our children and female co‐researchers. Specifically, we focus on issues of access and rapport; the impacts of their presence on our positionality; and the implications these have for power relations and research outcomes. We demonstrate how being accompanied entangles our personal and professional selves and can result in more egalitarian power relations as we become “observers observed”. We argue that by paying attention to the dynamics of accompanied fieldwork, there is the potential to enhance the conceptual focus of our methodological concerns and to provide a more theoretically sophisticated mode of exploring the ways in which our multiple identities intersect while in “the field”. 相似文献