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This article presents an econometric analysis of land‐cover change in western Honduras. Ground‐truthed satellite image analysis indicates that between 1987 and 1996 net reforestation occurred in the 1,015‐km2 study region. While some reforestation can be attributed to a 1987 ban on logging, the area of reforestation greatly exceeds that of previously clear‐cut areas. Further, new area was also deforested between 1987 and 1996. Thus, the observed land‐cover changes represent a complex mosaic of changing land‐use patterns across time and space. The analysis contributes to the literature on land‐cover change modeling in that: (1) it compares two econometric approaches to capture complex and often bidirectional changes in land cover from 1987 to 1996 as a function of agricultural suitability and transportation costs, and (2) it addresses techniques to identify and correct for spatial autocorrelation in a categorical regression framework. 相似文献
2.
Bruce J. MacFadden 《Quaternary Research》2005,64(2):113-124
The toxodont megaherbivores Toxodon and Mixotoxodon were endemic to South and Central America during the late Quaternary. Isotopic signatures of 47 toxodont teeth were analyzed to reconstruct diet and ancient habitat. Tooth enamel carbon isotope data from six regions of South and Central America indicate significant differences in toxodont diet and local vegetation during the late Quaternary. Toxodonts ranged ecologically from C3 forest browsers in the Amazon (mean δ13C = −13.4‰), to mixed C3 grazers and/or browsers living either in C3 grasslands, or mixed C3 forested and grassland habitats in Honduras (mean δ13C = −9.3‰), Buenos Aires province, Argentina (δ13C = −8.7‰), and Bahia, Brazil (mean δ13C = −8.6‰), to predominantly C4 grazers in northern Argentina (δ13C = −4.4‰), to specialized C4 grazers in the Chaco of Bolivia (δ13C = −0.1‰). Although these toxodonts had very high-crowned teeth classically interpreted for grazing, the isotopic data indicate that these megaherbivores had the evolutionary capacity to feed on a variety of dominant local vegetation. In the ancient Amazon region, carbon isotope data for the toxodonts indicate a C3-based tropical rainforest habitat with no evidence for grasslands as would be predicted from the Neotropical forest refugia hypothesis. 相似文献
3.
This study developed an impervious surface fraction algorithm (ISFA) for automatic mapping of urban areas from Landsat data. We processed the data for 2001 and 2014 to trace the urbanization of Tegucigalpa, the capital city of Honduras, using a four-step procedure: (1) data pre-processing to perform image reflectance normalization, (2) quantification of impervious surface area (ISA) using ISFA, (3) accuracy assessment of mapping results and (4) change analysis of urban growth. The mapping results compared with the ground reference data confirmed the validity of ISFA for automatic delineation of ISA in the study region. The overall accuracy and Kappa coefficient achieved for 2001 were 92.8% and 0.86, while the values for 2014 were 91.8% and 0.84, respectively. The results of change detection between the classification maps indicated that ISA increased approximately 1956.7 ha from 2001 to 2014, mainly attributing to the increase of the city’s population. 相似文献
4.
《The Professional geographer》2013,65(2):158-174
How researchers describe groups living within or near the world's tropical rain forests has important implications for how and why these groups are targeted for assistance by conservation and development organizations. This article explores how data about market behavior can be used to assess one aspect of forest peoples’ livelihoods: their “dependence” on forest resources as a source of market income. With the intent of revealing the importance of methodology to how we describe forest peoples’ livelihoods, I draw from a multiyear survey of market activity among the Tawahka Sumu of Honduras and distinguish nested measures of the Tawahkas’ engagement in forest-product sale. Results indicate that whether or not the Tawahka —or any forest group — can be considered financially “dependent” on forest resources depends on the spatial and temporal scales at which data are aggregated. As a group, the Tawahka earned 18 percent of total market income from forest-product sale, but their group profile masked a high degree of heterogeneity at the village and household level. Similarly, multiyear data indicated that while group-level generalizations adhere from year to year, they belie considerable change in households’ market behavior across years. I discuss three ways in which the findings are relevant to the theory and practice of conservation and development in the humid tropics. I emphasize the importance of spatial scale in interventions, how market-oriented conservation schemes can benefit from a broader conceptualization of the economic context in which forest-product sale occurs, and how longitudinal analysis can reveal the dynamism of forest peoples’ livelihoods. 相似文献
5.
Responding to the coffee crisis: a pilot study of farmers' adaptations in Mexico, Guatemala and Honduras 总被引:6,自引:0,他引:6
This article explores the impacts of market shocks and institutional change on smallholder livelihoods, and the challenge of adaptation in Mexico, Guatemala and Honduras. The rapid decline in coffee prices since the dissolution of the International Coffee Agreement in 1989 has had widespread and profound impacts across coffee-producing regions. The data collected in the three case studies of this project confirm the severity of the impact, particularly in the Mexican and Guatemalan communities. They also illustrate the importance of the historical relationship between farmers and public institutions in defining farmers' perception of risk, their awareness of the nature of the changes they face, and thus the flexibility of their responses to present and future uncertainty. The project's findings indicate that the existence and development of local networks among farmers, service providers and information sources may be critical for facilitating adaptation, particularly in the context of economic liberalization and globalized agriculture. 相似文献
6.
The determinants of primary health care utilization: a comparison of three rural clinics in Southern Honduras 总被引:2,自引:0,他引:2
Primary health care utilization is poorly understood in many parts of the developing world. This is especially true in rural places, such as Santa Lucia, Intibuca, Honduras, where there are only three primary health care facilities servicing almost 12,000 people, and generally speaking access to care is limited. This study examines the factors that can be used to explain primary health care utilization, and aims to improve the understanding of patient utilization behavior. A better understanding of utilization can be used by health service planners to improve primary health care delivery in this and similar locations. The findings of this research indicate that utilization can be explained, to a large extent, by factors relating to economic status and walking time to clinic. These findings are consistent with findings from prior research. In addition, a home territory variable is used to examine spatial variations of utilization behavior. This variable has not been considered in previous utilization research, and is found to be a very significant determinant of health facility utilization in the study area. 相似文献
7.
RICHARD SYMANSKI 《Geographical review》1998,88(4):571-579
ABSTRACT. Hurricane Mitch, the most deadly hurricane to strike the Western Hemisphere in two centuries, killed at least 10,000 people in Honduras, Nicaragua, and El Salvador and left tens of thousands homeless. Some needed food; others, medical attention. Americans, Europeans, Mexicans, and others almost immediately responded to the widespread devastation by sending large donations of food, clothing, and medicine. Six weeks after Mitch struck the Honduran mainland, the author traveled to Honduras with the aim of photographing the physical damage and its effect on humans. In San Pedro Sula he was sidetracked by the issue of where the refugees were being housed and whether they were receiving the donations that had been sent on their behalf. This essay narrates that search and what he found. 相似文献
8.
Contract farmers in central Honduras have been producers of Asian vegetables for American markets since 1989. Contract farming
holds the potential to provide benefits to small farmers who would otherwise be unable to access export markets but production
relations between firms and farmers are often asymmetric and can be exploitative. Poor communication and legacies of mistrust
between commodity agriculture and small farmers lead to ambiguities in the contracting system that are misinterpreted by both
firms and farmers, creating social tensions between contracting parties. This article will consider how farmers’ navigation
of the contracting system and competition between export firms has led to changes in the system. Through competition for a
limited pool of outgrowers, firms adjust their policies in favor of farmers without explicit attempts of labor organization
on the part of the farmers.
相似文献
Valerie ImbruceEmail: |
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10.
The 2005 Atlantic hurricane season was unprecedented in terms of storm activity in the United States, Mexico, Central America and Caribbean. Given the impacts of hurricanes Katrina and Rita, the Honduran Mosquitia sparked little attention despite being hit by two hurricanes and a tropical storm in 2005. This article recounts the history of these storms in the Afro-Caribbean community of Batalla, drawing from public weather advisories and testimony of local residents obtained through participatory research. We contextualise this local history with results from the first paleotempestological study undertaken in the Mosquitia to shed light on long-term risk of catastrophic storms in the region and to demonstrate the value of integrating these two research approaches. Our findings contribute to recent ethnographic research on hazards by describing how a coastal people understand and respond to tropical cyclones and how landscape change influences the vulnerability of a coastal area. Although residents have not witnessed a storm as intense as those documented in the paleotempestological record, their knowledge and perceptions show how tropical cyclones can be disasters while leaving behind no sedimentary records. The paleotempestological evidence, however, reminds us that catastrophic hurricanes have struck the Mosquitia in the past and will do so again in the future. Understanding the interactions between contemporary human perceptions and responses and long-term hurricane risk provides insight for emergency managers and local stakeholders to better prepare for such a catastrophic event. 相似文献