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1.
Chih Hoong Sin 《Area》2003,35(3):305-312
The intersubjective dialogic exercise through which identities and knowledge are constructed exists in a dialectic relation with the 'place' of the interview. The in situ nature of interviewing should not be overlooked. Two case studies of interviews conducted with older people in Britain about their social network and support are used to illuminate two aspects of the socio-spatial construction of interview data. First, interview sites can yield important information about the way participants construct their individual and social identities. Second, such identities can influence interviewer–interviewee dynamics.  相似文献   
2.
Fuelwood Development for Energy in Sudan project (GCP/SUD/033/NET) is undertaking research to formulate management plans for Sudan ecologically marginal forests. Rawashda and Wad Kabu forests are taken as examples to initiate sound plans. It is believed that the study of socio-economic parameters of forests users is an essential component to achieve such plan. This study is also fundamental for attaining an integrated land use system, as a prime option of natural resource use. This study is, consequently, aiming at:
  1. Providing the base line information of the different communities identified in Tab 3 and using the two forests.
  2. Examine people's attitude, perception, participation options in maintenance and management of the two forests. Such parameters are also vital for adoption of an integrated land use strategy in the future.
  3. Based on (i) and (ii) to outline broadly the most relevant plan of management land use strategy to be adopted, based on community self-generated options of institutions and objectives of use.
The main findings in this context can be summarized in the following:
  1. A complex pattern of economic activities (Tab 3) ranging from pure pastoral nomadism to modern mechanized farming, still characterized by combination of related activities of agricultural/livestock breeding, agriculture/forest resource use, etc. This diversity in activities, which is mostly dependent on the natural resource base, gives a sound base for any option of an integrated land use system.
  2. Perception and attitude analysis have revealed a growing awareness of the role of the forest resources in the economy as source of grazing, domestic needs and source of income. This awareness is supported by willingness to participate in any integrated land use plan, yet from a different stand point and objective. Preference of self-generated channels is quite evident, but with a specified role of the government.
  3. The major finding is that, and among all communities, the situation is mature for action, although at different levels.
Therefore, each community could be approached along relevant lines of action, as an initial phase before attaining a comprehensive land use plan. On-farm trials (OFTs) or in-herd trials seem to be more relevant compared with expert controlled trials. Any plan of action needs to be preceded by revision of present land tenure systems, establishing grass-root institutions, reorientation of concerned government departments, intensive extension programme and careful formulation of projects, execution and follow-up plans. Such steps need to be geared to narrow the ‘Perception gap’ of development between participants or users and planners.  相似文献   
3.
The Butana region of central Sudan is famous for its animal wealth and extensive pastures. Yet scarcity of water resources in the area especially during the dry seasons handicaps the proper utilization of these pastures. The area is occupied by non-water-bearing basement rocks and the only source of water is from direct run-off. Thus large numbers of small-size water reservoirs, haffirs, were constructed, but these are inadequate to provide enough water for the growing human and animal population. An all-year lake is here proposed to be constructed utilizing the ring-structure the Jebel Qeili igneous complex, central Butana. This lake is expected to solve the present water problem and meet the future demand of central Butana at the present rate of human and animal growth.  相似文献   
4.
5.
Harng Luh Sin 《Geoforum》2010,41(6):983-992
Existing studies have often suggested that volunteer tourism, with strong overtones of “social”, “justice” and “pro-poor” tourism, has the capacity to bring about positive impacts to local communities in host destinations. Wearing, for example, advocates volunteer tourism “as a development strategy leading to sustainable development and centering the convergence of natural resource qualities, locals and the visitors that all benefit from tourism activity” (Wearing, 2001: p. 12). Indeed, underlying assumptions in volunteer tourism suggest that it is a form of tourism that allows the empowering of locals in host-communities, and when compared to conventional modes of tourism, volunteer tourism allows cultural interaction and understanding to be developed between hosts and tourists in the longer period and more intimate form of contact. This, together with very direct and tangible outcomes of volunteer projects, appears to put in place a platform where locals and tourists both have the power to actively negotiate their identities and relations with each other.However, despite these deep-seated assumptions about the positive value in volunteer tourism, little empirical research has been conducted to assess the situation on the ground. Existing literature is largely centered on the volunteer tourist, with little works directly regarding the perspectives of host-communities. This places much uncertainty on whether the assumed benefits of volunteer tourism are indeed realized. Adopting a geographical approach, this paper begins with a review of existing discussions on the geographies of care and responsibility, and its intersections with literature on responsible tourism (of which volunteer tourism is often seen to be a part of). Opinions re-presented in this paper are based on interviews with 14 respondents in Cambodia (including local Cambodians, non-government organizations’ (NGO) and missionary workers that have previously hosted volunteer tourists in Cambodia. This paper thus explores both positive and negative opinions of volunteer tourism from the perspective of host-communities, and endeavors to contribute a balanced discussion to the limited literature regarding host-communities’ perspectives in tourism development.  相似文献   
6.
An upgraded version of the Eta model   总被引:2,自引:0,他引:2  
Upgrades implemented over a number of years in an open source version of the Eta model, posted at the CPTEC web site http://etamodel.cptec.inpe.br/, are summarized and examples of benefits are shown. The version originates from the NCEP’s Workstation Eta code posted on the NCEP web site http://www.emc.ncep.noaa.gov/mmb/wrkstn_eta, which differs from the NCEP’s latest operational Eta by having the WRF-NMM nonhydrostatic option included. Most of the upgrades made resulted from attention paid to less than satisfactory performance noted in several Eta results, and identification of the reasons for the problem. Others came from simple expectation that including a feature that is physically justified but is missing in the code should help. The most notable of the upgrades are the introduction of the so-called sloping steps, or discretized shaved cells topography; piecewise-linear finite-volume vertical advection of dynamic variables; vapor and hydrometeor loading in the hydrostatic equation, and changes aimed at refining the convection schemes available in the Eta. Several other modifications have to do with the calculation of exchange coefficients, conservation in the vertical diffusion, and diagnostic calculation of 10-m winds. Several examples showing improved performance resulting from the dynamics changes are given. One includes a case of unrealistically low temperatures in several mountain basins generated by a centered vertical advection difference scheme’s unphysical advection from below ground, removed by its replacement with a finite-volume scheme. Another is that of increased katabatic winds in the Terra Nova Bay Antarctica region. Successful forecast of the severe downslope zonda wind case in the lee of the highest peaks of the Andes is also shown, and some of the recent successful verification results of the use of the upgraded model are pointed out. The code is used at numerous places, and along with setup information it is available for outside users at the CPTEC Eta web site given above.  相似文献   
7.
Downscaling of South America present climate driven by 4-member HadCM3 runs   总被引:5,自引:2,他引:3  
The objective of this work is to evaluate climate simulations over South America using the regional Eta Model driven by four members of an ensemble of the UK Met Office Hadley Centre HadCM3 global model. The Eta Model has been modified with the purpose of performing long-term decadal integrations and has shown to reproduce “present climate”—the period 1961–1990—reasonably well when forced by HadCM3. The global model lateral conditions with a resolution of 2.5° latitude?×?3.75° longitude were provided at a frequency of 6?h. Each member of the global model ensemble has a different climate sensitivity, and the four members were selected to span the range of uncertainty encompassed by the ensemble. The Eta Model nested in the HadCM3 global model was configured with 40-km horizontal resolution and 38 layers in the vertical. No large-scale internal nudging was applied. Results are shown for austral summer and winter at present climate defined as 1961–90. The upper and low-level circulation patterns produced by the Eta-CPTEC/HadCM3 experiment set-up show good agreement with reanalysis data and the mean precipitation and temperature with CRU observation data. The spread in the downscaled mean precipitation and temperature is small when compared against model errors. On the other hand, the benefits in using an ensemble is clear in the improved representation of the seasonal cycle by the ensemble mean over any one realization. El Ni?o and La Ni?a years were identified in the HadCM3 member runs based on the NOAA Climate Prediction Center criterion of sea surface temperature anomalies in the Ni?o 3.4 area. The frequency of the El Ni?o and La Ni?a events in the studied period is underestimated by HadCM3. The precipitation and temperature anomalies typical of these events are reproduced by most of the Eta-CPTEC/HadCM3 ensemble, although small displacements of the positions of the anomalies occur. This experiment configuration is the first step on the implementation of Eta-CPTEC/HadCM3 upcoming experiments on climate change studies that are discussed in a companion paper.  相似文献   
8.
Considered is a case of the cumulonimbus cloud development in the southwestern part of Saudi Arabia with a very high precipitation intensity. The height of the cloud top amounted to 14 km and the radar reflectivity, to 60 dBZ. Carried out is the comparison of remote methods of measuring the intensity of precipitation from the cloud under study: the radar (using the relationship between the reflectivity and precipitation intensity) and satellite IR-radiometric (based on the results of sounding with the SEVERI radiometer installed at the Meteosat-8 satellite) methods. A split-window technique was used for detecting the position of the cloud top from the radiometric observations. The analysis enabled to select the best relationships for estimating the precipitation intensity from the data of radar and satellite measurements. The computations based on these relationships correspond most closely to the ground-based measurements with the precipitation gage.  相似文献   
9.
The accurate estimate of the surface longwave fluxes contribution is important for the calculation of the surface radiation budget, which in turn controls all the components of the surface energy budget, such as evaporation and the sensible heat fluxes. This study evaluates the performance of the various downward longwave radiation parameterizations for clear and all-sky days applied to the Sertãozinho region in São Paulo, Brazil. Equations have been adjusted to the observations of longwave radiation. The adjusted equations were evaluated for every hour throughout the day and the results showed good fits for most of the day, except near dawn and sunset, followed by nighttime. The seasonal variation was studied by comparing the dry period against the rainy period in the dataset. The least square linear regressions resulted in coefficients equal to the coefficients found for the complete period, both in the dry period and in the rainy period. It is expected that the best fit equation to the observed data for this site be used to produce estimates in other regions of the State of São Paulo, where such information is not available.  相似文献   
10.
Results are presented of aircraft investigations of microphysical properties of an Arctic nimbostratus cloud (Ns). The data are obtained over the Beaufort Sea using the C-130 instrumented aircraft of National Center for Atmospheric Research (NCAR) of the USA. One of the most modern instrument set designed to study microphysical cloud structure is used. The particle size spectra and averaged microphysical cloud characteristics are obtained. Inhomogeneity of cloud structure is analyzed. The radar measurements of the cloud parameters are compared against the aircraft in-situ measurements.  相似文献   
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