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1.
The concept of community identity has often been employed to explain ways in which communities respond to agents that impact community well-being. Using a case study of the Florida cattlemen community, we examine how cattlemen understand and perceive regulatory efforts to recover the Florida panther on private ranch lands. The data comes from participants in the Florida cattlemen community, and was collected through in-depth interviews (n = 13), group interviews (n = 32), and written comments associated with a survey about panther conservation (n = 78). Our findings indicate that some cattlemen in Florida have a strong sense of community identity. Perceptions of government actions and variation in economic risks are critical factors in understanding how this community responds to federal interventions. Our findings suggest that the concept of community identity can be used to explain the responses of agricultural landowners to governmental policies that are perceived as a threat to collective identity.  相似文献   

2.
Most of the literature to date proposes approximations to the determinant of a positive definite n × n spatial covariance matrix (the Jacobian term) for Gaussian spatial autoregressive models that fail to support the analysis of massive georeferenced data sets. This paper briefly surveys this literature, recalls and refines much simpler Jacobian approximations, presents selected eigenvalue estimation techniques, summarizes validation results (for estimated eigenvalues, Jacobian approximations, and estimation of a spatial autocorrelation parameter), and illustrates the estimation of the spatial autocorrelation parameter in a spatial autoregressive model specification for cases as large as n = 37,214,101. The principal contribution of this paper is to the implementation of spatial autoregressive model specifications for any size of georeferenced data set. Its specific additions to the literature include (1) new, more efficient estimation algorithms; (2) an approximation of the Jacobian term for remotely sensed data forming incomplete rectangular regions; (3) issues of inference; and (4) timing results.  相似文献   

3.
This study represents a step towards developing seasonal climate inferences by using high-resolution modern data sets. The importance of seasonal climate changes is highlighted by the instrumental record of a meteorological station close to our study site (lac du Sommet in the Laurentian Mountains, Québec, Canada): Between 1966 and 2001, May temperatures increased significantly by 3.1°C (r = 0.41, n = 35, p < 0.01) but annual mean temperatures only by 0.6°C (r = 0.21, n = 35, p > 0.05). Comparison of this instrumental record with fossil diatom assemblages in a sediment core from lac du Sommet showed that axis one of a principal component analysis (PCA) of the fossil diatoms was best correlated with wind velocity in June (r = 0.62, n = 19, p < 0.005) and that past diatom production was significantly enhanced in periods with colder July temperatures (r =  ?0.77, n = 19, p < 0.0005) and higher wind velocity in June (r = 77, n = 19, p < 0.0005). The strong impact of the spring and summer conditions on overall diatom composition and productivity suggests that seasonal lake responses to climate are more important than annual mean temperatures. However, the seasonal dynamics of diatom communities are not well understood, and seasonality is rarely inferred effectively from lake sediment studies. Our research presents a pilot study to answer a twofold question: Is it possible to identify diatom communities which are typical for warmer or colder seasonal climate using sediment traps, and if it is, can this knowledge be used to infer seasonal climate conditions from fossil diatom assemblages? To address these questions, the seasonal dynamics of diatom communities and water chemistry were studied using sediment traps and water samples at biweekly intervals in four lakes distributed along an altitudinal gradient in the Laurentian Mountains from May through October 2002. Date of ice break-up was significantly related to the diatom assemblages taken in spring and uncorrelated to other significant environmental variables. Summer water temperature, circulation of the water column and pH explained a significant part of the biological variance in summer, and total nitrogen (TN) explained most of the biological variance in autumn. To infer these variables, weighted averaging partial least squares models were applied to the seasonal data sets. Inferred ice break-up dates were significantly correlated with number of days below 0°C in April (r = 0.52, n = 19, p < 0.025), inferred circulation of the water column was significantly related to measured wind velocity in June (r = 0.64, n = 19, p < 0.005), inferred summer water temperature and inferred pH was significantly related to measured July air temperature (r = 0.50, r =  ?53, n = 19, p < 0.025) and inferred TN autumn concentrations had an inverse relationship to August temperatures (r =  ?0.53, n = 19, p < 0.01). This comparison of the historical record with diatom-inferred seasonal climate signals, based on the comparison of fossil diatom assemblages with modern sediment trap data of high temporal resolution, provides a promising new approach for the reconstruction of seasonal climate aspects in paleolimnological studies.  相似文献   

4.
We investigated the implementation and sustainability of village conservation agreements and village conservation grants facilitated by an integrated conservation and development project (ICDP) around the Kerinci Seblat National Park, Sumatra, Indonesia, 5 years after the project closed. Forty-three percent of agreement actions (n = 180) and 30% of grant activities (n = 74) were sustained. Informants identified numerous factors influencing success, but statistical tests failed to detect simple explanations. Conservation-livelihood agreements have a greater chance of success when preexisting factors are understood and the purpose of the agreement itself is clearly defined.  相似文献   

5.
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6.
The concept of sustainability includes a personal and societal imperative to assume responsibility for the future outcomes of present actions, to look forward, or in other words, to have a future orientation. Future orientation is both a personality trait and a cultural characteristic that strongly influences behavioral decisions on the personal and societal levels, respectively. This research addresses the relationship between future orientation and pro-environmental behavior on both levels. In a representative sample of the population (n = 1216), we found that individuals with developed future orientation demonstrated more pro-environmental tendencies. On the cross-cultural level we also found that in countries that conduct future-oriented practices in general the environment benefits, because the citizens tend to behave more pro-environmentally. The parallel between factors that affect future orientation and environmental behavior and the implications for promoting pro-environmental practices in the social and personal levels are discussed.  相似文献   

7.
The complexity of hydrological processes and lack of data for modeling require the use of specific tools for non-linear natural phenomenon. In this paper, an effort has been made to develop a conjunction model – wavelet transformation, data-driven models, and genetic algorithm (GA) – for forecasting the daily flow of a river in northern Algeria using the time series of runoff. This catchment has a semi-arid climate and strong variability in runoff. The original time series was decomposed into multi-frequency time series by wavelet transform algorithm and used as inputs to artificial neural networks (ANN) and adaptive neuro-fuzzy inference system (ANFIS) models. Several factors must be optimized to determine the best model structures. Wavelet-based data-driven models using a GA are designed to optimize model structure. The performances of wavelet-based data-driven models (i.e. WANFIS and WANN) were superior to those of conventional models. WANFIS (RMSE = 12.15 m3/s, EC = 87.32%, R = .934) and WANN (RMSE = 15.73 m3/s, EC = 78.83%, R = .888) models improved the performances of ANFIS (RMSE = 23.13 m3/s, EC = 54.11%, R = .748) and ANN (RMSE = 22.43 m3/s, EC = 56.90%, R = .755) during the test period.  相似文献   

8.
In this paper, I revisit the role of Soviet legacy factors in explaining today’s housing inequalities in a midsized post-Soviet city by investigating social, demographic, economic and geographic determinants of perceived housing quality. Building on a sample survey dataset (n = 3,000) that brings together both Soviet legacy effects and more universal influences on housing inequality, it is shown that various aspects of Soviet housing policy can be traced as well-preserved legacies today. The survey was conducted in 2009 in Stakhanov, Ukraine, and the method of analysis is binomial logistic regression. By capturing both the social costs attributed to the post-Soviet transition crisis as well as the underlying legacy factors inherited from the Soviet epoch, the findings suggest that any analysis of housing inequalities or residential segregation in the post-socialist city must come to terms with the impacts of socialist-era economic priorities on the urban social landscape.  相似文献   

9.
Illegal disposal of waste is a significant management issue for contemporary governments because of the hazards posed to both human and ecosystem health. Understanding the complex distribution pattern of illegal waste and the range of economic, environmental and social factors influencing this distribution is valuable for improving the effectiveness and efficiency of waste management efforts. This article examines the applicability of mapping illegal waste disposal in the Sunshine Coast (Queensland, Australia) through the identification and integration of predictive spatial data in a geographic information system. A statistical model of illegal waste disposal was developed using a binary logistic regression analysis to identify explanatory variables suitable for predicting the distribution of illegal waste. Five statistically significant explanatory variables were identified through this analysis: population density, primary land use, distance to the nearest road, waste facility and roadside amenity. The generated statistical model had a predictive success of 86.1% with all indicators suggesting good model fit (χ2 = 474.3, P = 0 with df = 22) across the study area. Standardised spatial data on each explanatory variable were combined using a weighted linear combination analysis and the results were classified into five categories from very low to very high illegal waste disposal potentials using the equal interval method. The resultant mapping identified 6.9% of the study area as having very high illegal waste disposal potential, and subsequent validation indicated that 32.9% of known illegal waste disposal sites were located within these areas.  相似文献   

10.
Abstract

Characterizing gully cross sections (GCs) is essential for calculating the volume and erosion rate of the gully. However, little research has focused on modeling the morphology of GCs. This study investigated 456 GCs with a laser distance meter located at the mouth, middle, and head of 152 gullies in the Yuanmou Dry-hot Valley of China; mapped them with AutoCAD software; fitted them with 2nd–6th degree polynomial functions, and discussed the correlation between the coefficients and the morphology of GCs. The results showed that: (1) using a 2nd-degree polynomial function (y = ax2 + bx + c) to describe the morphology of GCs produced a better result than other polynomial functions; (2) the coefficient a of 2nd-degree polynomial function was correlated with depth (r = ?0.226, p < 0.01), gradient (r = 0.545, p < 0.01), and activities; and (3) the symmetry axis (?b/2a) of 2nd-degree polynomial function increased with gully change from left-deflection to right-skewed, and the absolute value showed the asymmetrical degree (r = 0.216, p < 0.01). This study will not only help to understand the morphology and evolution of gullies, but will also provide a scientific basis for prevention of gully erosion.  相似文献   

11.
Gully erosion in the Black Soil Region of China has posed a threat to food security. This study aimed to determine the spatial distribution and morphologic characteristics of gullies in the region and their topographic thresholds. A 28 km2 watershed was surveyed and 117 gullies measured. The results showed that: (1) Gullies were distributed equally on both hillslope and valley floor positions, with a total gully density of .66 km/km2. (2) The mean depth, width, and cross-sectional area of gullies were .74 m, 2.39 m, and 2.43 m2, respectively. These characteristics varied among gullies according to their topographic positions and slope gradients. Individual gully volume (V) was well predicted from gully length (L) by V = 2.08L0.96 (r2 = .66). Total gully volume (V) of each sub-watershed was predicted from mean slope gradient (S) and drainage area (A) as V = 275800S ? 8600A (r2 = .73). (3) Gully erosion was more serious in steeper sub-watersheds and steeper hillslope positions. Gullies were wider in regions with relatively larger drainage areas, except for those developed in the main valley. The topographic threshold for gully initiation was S = .10A?0.34, which indicated gully erosion was dominated by surface runoff. (4) Human activities, such as road construction, played a significant role in gully erosion.  相似文献   

12.
Gambling using electronic gaming machines (EGMs) has emerged as a significant public health issue. While social impact assessments are required prior to the granting of new gaming machine licenses in Australia, there are a few established techniques for estimating the spatial distribution of a venue’s clientele. To this end, we calibrated a Huff model of gambling venue catchments based on a geocoded postal survey (n = 7040). We investigated the impact of different venue attractiveness measures, distance measures, distance decay functions, levels of spatial aggregation and venue types on model fit and results. We then compared model estimates for different behavioural subgroups. Our calibrated spatial model is a significant improvement on previously published models, increasing R2 from 0.23 to 0.64. Venue catchments differ radically in size and intensity. As different population subgroups are attracted to different venues, there is no single best index of venue attractiveness applicable to all subpopulations. The calibrated Huff model represents a useful regulatory tool for predicting the extent and composition of gambling venue catchments. It may assist in decision-making with regard to new license applications and evaluating the impact of health interventions such as mandated reductions in EGM numbers. Our calibrated parameters may be used to improve model accuracy in other jurisdictions.  相似文献   

13.
High-resolution, well-calibrated records of lake sediments are critically important for quantitative climate reconstructions, but they remain a methodological and analytical challenge. While several comprehensive paleotemperature reconstructions have been developed across Europe, only a few quantitative high-resolution studies exist for precipitation. Here we present a calibration and verification study of lithoclastic sediment proxies from proglacial Lake Oeschinen (46°30′N, 7°44′E, 1,580 m a.s.l., north–west Swiss Alps) that are sensitive to rainfall for the period AD 1901–2008. We collected two sediment cores, one in 2007 and another in 2011. The sediments are characterized by two facies: (A) mm-laminated clastic varves and (B) turbidites. The annual character of the laminae couplets was confirmed by radiometric dating (210Pb, 137Cs) and independent flood-layer chronomarkers. Individual varves consist of a dark sand-size spring-summer layer enriched in siliciclastic minerals and a lighter clay-size calcite-rich winter layer. Three subtypes of varves are distinguished: Type I with a 1–1.5 mm fining upward sequence; Type II with a distinct fine-sand base up to 3 mm thick; and Type III containing multiple internal microlaminae caused by individual summer rainstorm deposits. Delta-fan surface samples and sediment trap data fingerprint different sediment source areas and transport processes from the watershed and confirm the instant response of sediment flux to rainfall and erosion. Based on a highly accurate, precise and reproducible chronology, we demonstrate that sediment accumulation (varve thickness) is a quantitative predictor for cumulative boreal alpine spring (May–June) and spring/summer (May–August) rainfall (rMJ = 0.71, rMJJA = 0.60, p < 0.01). Bootstrap-based verification of the calibration model reveals a root mean squared error of prediction (RMSEPMJ = 32.7 mm, RMSEPMJJA = 57.8 mm) which is on the order of 10–13 % of mean MJ and MJJA cumulative precipitation, respectively. These results highlight the potential of the Lake Oeschinen sediments for high-resolution reconstructions of past rainfall conditions in the northern Swiss Alps, central and eastern France and south-west Germany.  相似文献   

14.
Pronounced climate warming during the past century has been well documented in high-latitude regions. Nonetheless, considerable heterogeneity exists in northern climate trends. We examined the roles of cryospheric landscape and lake depth in modulating the rate and magnitude of local climate responses through a paleolimnological study of lakes from southwest Yukon, Canada. By sampling lakes at varying distances from the Wrangell-St. Elias ice fields, we hypothesized that, for lakes of similar maximum depth, sites closest to the ice fields would be relatively complacent in terms of their chironomid and diatom assemblage changes over the past ~200 years. This hypothesis is based on the moderating effect of the glaciers on local climate, which would be most pronounced in the lakes nearest to the ice fields. However, given the known ecological differences between deep and shallow lakes, we further predicted that, for a given distance from the ice fields, a sediment record from a shallower lake would show the greatest change in stratigraphic subfossil assemblages. Because of the complicated shape of the ice fields, we applied the longitude for each site (which decreases from west to east) to approximate the proximity of our study lakes to the ice fields. Consistent with our predictions, we observed a space-transgressive pattern in the chironomid assemblage turnover that was associated with their proximity to the ice fields (r = ?0.75, P = 0.034, n = 8) across lakes of similar depth (mean maximum depth ± 1, SE = 18.1 ± 2.6 m). Considering a broader network of lakes that represented a greater range in maximum depth (4.9–29 m), we found that differences in subfossil chironomid assemblages between the modern and ca. AD 1800 sediment layers were strongly related to lake depth (r = ?0.77, P < 0.001, n = 15), but failed to detect a significant relationship with latitude or longitude (i.e. our proxy for proximity to the ice fields). Similarly, our comparative high-resolution analyses of two lakes with distinct lake morphometries, but similar proximities to the ice fields, demonstrated the predicted contrasting pattern: we observed pronounced post-1880 changes in the biotic assemblages in the shallow lake and a muted and delayed response (i.e. ~1970s) in the deeper lake. Our findings confirm that cryospheric landscape features can strongly modulate regional climate. Furthermore, our work shows that investigators need to be conscious of how climate change affects the structure and functioning of lakes of different typologies, which influences the way in which paleoclimate signals are recorded and interpreted.  相似文献   

15.
黄秉维院士是我国地学、资源、环境领域的伟大思想家与设计大师。作为新中国地理学奠基人, 他为我国地理科学的发展做出了巨大贡献。值黄秉维院士诞辰百年之际, 作者回顾了黄秉维院士提出的四个学术问题:“生态环境”、“水热平衡在地理学研究中的作用”、“确切地估计森林的作用”和“钝端科学”, 并结合作者的相关研究工作阐述了对这四个问题的认识与体会, 以印证他的学术思想对后学者研究工作的重要引领与指导作用。  相似文献   

16.
《The Journal of geography》2012,111(3):163-168
Abstract

This paper explores the concept of relevancy in the context of an introductory physical geography course. The concern is with a relevant content and structure. Both are introduced through a problem-orientation. Current societal problems related to the physical environment are used to introduce students to conditions and processes involving environmental elements such as atmosphere, water, soil, vegetation, and topography. Because they are societal problems, the additional element, man, is included. The structure assumes a priori that the student has some prior knowledge of environmental problems. With a relatively high level of individual involvement, the student is asked to utilize this knowledge in learning about environmental processes and physical geographic concepts. Feedback from student to instructors is maximized through greater reliance on discussion groups, exercises, papers, and a problem-solving examination. In transmitting subject matter and environmental problems information, greater reliance is placed on readings and less on lectures.  相似文献   

17.
This article highlights the results of an action research to upgrade mountain farmers of bay leaf (Cinnamomum tamala Nees and Eberm) in Udayapur district of Nepal. Farmers received low prices, lacked market information, capacities, and institutional mechanisms, and were exploited by traders. To address these constraints, three independent but interlinked pro-poor value chain (VC) upgrading strategies comprising VC coordination upgrading and horizontal and vertical contractualization were implemented. Information was collected from focus-group discussions with collectors, traders, and facilitators, and a questionnaire was used to collect pre- and postintervention data (n = 120). VC upgrading strategies improved harvesting practices, increased farmers’ bargaining power, and led to a threefold increase in price, which increased household incomes. Results demonstrated improved terms of participation of farmers and a general increase in market price of bay leaf in Udayapur. The study approach can be up scaled to reduce poverty from high value products.  相似文献   

18.
A storage-efficient contour generation method, focusing on planar contours, is developed. Given cartographic elevations on a rectangular lattice, a continuous bivariate function, z = f(x, y), is determined by interpolating the elevation values. Then, we focus on a contour determined by z = constant. The contour curve is partitioned into multiple sections, each of which is exactly or approximately round. Three curvature types are introduced to evaluate the roundness of each section. The area and perimeter of the contour are computed by one-dimensional line integration using Green’s theorem. If the contour is open, it is divided into two curves starting from the same initial point, with the control points advancing in opposite directions. Two types of numerical experiments are performed to validate the effectiveness of the proposed method. One experiment uses an analytically defined elevation function and investigates the number of control points and computation time for a resulting computation error. The second experiment uses actual digital elevation model data of an isolated island in Japan and compares the proposed method with existing ones. Because the algorithm does not require lattice subdivision and the number of control points is drastically reduced, the proposed method is storage efficient.  相似文献   

19.
Areas affected by drought are increasing, and many lakes that provide potable water and recreation opportunities are located in drought-vulnerable areas. Understanding a population's attitudes toward conservation actions can improve communication initiatives, policy development, and education, which are all necessary for effective water resource management. However, little is known about stakeholders’ interactions with drought-influenced resources and the potential factors that form their water conservation attitudes. Using a mixed methods approach, we evaluated lake recreationists’ (n = 229) attitudes toward water conservation at a drought-impacted lake. We identified the relationships between two site-specific factors (place attachment and awareness of drought impacts), beliefs in climate change, concern for drought impacts, and water conservation attitudes. Results indicated concern for local drought impacts fully mediated the relationships between site-specific factors, beliefs in climate change, and attitudes toward water conservation behaviors. Implications for research, outreach, and water resource management are discussed.  相似文献   

20.
The highly skewed sex ratio at birth (SRB) in China has stimulated numerous studies. However, the geographic distribution of SRB is seldom investigated, particularly at the county level. The need for an understanding at this level has increased since the Chinese government initiated its ‘Care for Girls’ campaign to improve the survival rate of females. This campaign has been initiated in a set of pilot counties. In this article we assess the effectiveness of the set of pilot counties in Shandong province and propose two alternate configurations. To do this, we first assess the spatial distribution of the SRB values by county in Shandong, expressed as a z-score (zSRB) after correcting for the biologically expected SRB value and population size of zero-aged children. A local Moran's Ii analysis of the zSRB values indicates a significant high–high cluster in the southwest of the province. The Ii , zSRB and female deficit (the difference of the observed from biologically expected number of zero-aged females) were then used to define two alternate configurations for the pilot counties. A comparison of the current and alternate configurations against a Monte Carlo randomisation analysis shows that the current configuration is significantly different from a random selection (p < 0.05) for the two criteria of maximising the aggregate female deficit and maximising the zSRB. Although this is a good result, both alternate configurations were more significant (p < 0.001), and therefore represent potentially better configurations for the campaign given the criteria used. The spatial analysis approach developed here could be used to improve the effectiveness of the Care-for-Girls campaign in Shandong province, and elsewhere in China.  相似文献   

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