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1.
Biological and environmental changes are creating a growing demand for historical and global data sets. Comparing up-to-date ecological and biological findings with historical statements has become a major part of scientific work in the field of ecology. This evaluation and comparison procedure is very time-consuming while the availability of raw data is very low. Comparisons between original findings – if available – require a lot of work from print publication to digitalization or transformation to appropriate data formats. The effective use of working capacity is a general issue and has become important, should the use of information technologies be invoked to minimize time-wasting copy and paste operations.In this paper we aim to present a working repository for terrestrial biological data. The implementation of this type of data repository will provide various services to participating scientists as long as the final aim is the publication of these repositories. Furthermore, the security and long-term availability of environmental data is an issue of increasing importance to the scientific community. Unrepeatable sampling events and any data thus obtained are precious in time series analysis. For this reason, a well-structured storage of data is necessary for easy accessibility, retrieval and comparability. This is an important issue for the community of environmental scientists. The need to construct and implement repositories should prevail against all hitches and we are therefore describing our on-going task with the primary population of this kind of data repository. A biological and ecological information system is a matter of public interest and should also be a key issue for ecologists.  相似文献   

2.
Many environmental science research programmes now adopt community-based philosophies and designs, although there are few applications in Australian Indigenous communities. This research describes the development and testing of a framework of engagement to guide collaboration between Indigenous and non-Indigenous Australians during an environmental sciences research project. That project aimed to assess trepang (sea cucumber) stocks in Aboriginal waters, and determine the commercial harvest potential of the resource to local people. Its objectives were to undertake trepang survey and mapping, integrate Indigenous knowledge about the resource, and model the existing catch data of commercial fishers operating in the region. The framework of engagement developed to guide the research process comprised a goal, research stages, and a number of guiding principles for collaboration, which were constructed from content analysis of available guidelines and literature and from data gathered during expert interviews. Further data were gathered using participant observation, while implementing the trepang research in accordance with this framework of engagement, and these data were analysed to test and evaluate the framework. Findings indicate discursive and reflective approaches such as action research or adaptive management may better facilitate equitable research partnerships for sustainable development.  相似文献   

3.
The available data on known reserves of extracted resources have not previously been tabulated and graphed. In this article we compile the reserves data in one place for the first time. This serves to (1) show the trends in the reserves series, (2) make the series available to others, and (3) place the reserves data in the context of price data for which longer series have been available, and with which they can now be seen to be consistent in both showing increasing availability rather than increasing scarcity.  相似文献   

4.
With 7 years data on coyote prey use and availability, we tested three predictions based on optimal foraging: (1) the proportion eaten of the most profitable item is constant regardless of availability, (2) under a constant density of higher ranked prey, there is no relationship between the proportion eaten of low profitability items and their density, (3) the ratio of number consumed to availability for the highest ranking prey item should be negatively related to availability. We tested these predictions with regression analyses. We found no significant linear relationship between lagomorph availability and use. There was no significant linear relationship between percent frequency of occurrence of rodents nor arthropods and their respective availabilities for two levels of availability of lagomorphs. We found a significant negative relationship between number consumed/number available to availability for lagomorphs but not for rodents nor arthropods. The results supported the three predictions and we concluded that coyotes are foraging optimally.  相似文献   

5.
It is widely accepted that environmental change can influence human migration. In particular, the environment plays a role in migration processes in drylands, in which environmental change—including increasing variability of rainfall, increasing frequency of droughts, chronic water shortage, and land degradation—can heavily influence migration. However, systematic large-scale studies of the relationship between environmental factors and human migration are rare, and a global, consistent picture of environmental drivers of migration is lacking. In this study, we sought to fill this gap by analysing spatial patterns of environmental drivers of migration in drylands by performing a cluster analysis on spatially explicit global data. In this analysis, we focused explicitly on precipitation, aridity, drought, land degradation, soil constraints, and availability of cropland and pastures as potential environmental drivers of migration in drylands. In addition, we linked the identified clusters to two observed hotspots of out-migration—Burkina Faso and Northeast Brazil—to gauge the cluster results. Our results show that environmental drivers can be grouped into eight distinct clusters, and we identified the most severe environmental constraints for each cluster. These results suggest that out-migration—both in absolute and relative terms—occurs most frequently in a cluster that is constrained primarily by land degradation rather than water availability.  相似文献   

6.
The U.S. Geological Survey recently completed a digital coal resource assessment model of the Upper Pennsylvanian Pittsburgh coal bed, which indicates that after subtracting mined-out coal, 16 billion short tons (14 billion tonnes) remain of the original 34 billion short tons (31 billion tonnes) of coal. When technical, environmental, and social restrictions are applied to the remaining Pittsburgh coal model, only 12 billion short tons (11 billion tonnes) are available for mining. Our assessment models estimate that up to 0.61 billion short tons (0.55 billion tonnes), 2.7 billion short tons (2.4 billion tonnes), and 8.5 billion short tons (7.7 billion tonnes) could be available for surface mining, continuous mining, and longwall mining, respectively. This analysis is an example of a second-generation regional coal availability study designed to model recoverability characteristics for all the major coal beds in the United States.  相似文献   

7.
Although not well understood scientifically, integrated and diversified aquaculture-agriculture systems have a history of some two millennia in parts of South and Southeast Asia. With the extremely limited farm area and scanty resources available to the typical small-scale farmer of these regions, integrated agro-ecosystems, based on generations of empirical knowledge, provide a balanced diet and often a small marketable surplus for poor rural households, while continuously recycling nutrients and energy through the system, producing little waste, and maintaining a local ecological balance. Despite the few scientific data available on such systems, they are being widely advocated for use in developing countries with no prior experience of integrated farming.This paper (paper I) describes the environmental context and provides an overview of the mulberry dike-polycultural carp pond resource system of Leliu Commune, in the Zhujiang Delta of the People's Republic of China, where complex and highly productive integrated farming systems are operated on a geographical and economic scale unmatched elsewhere. Subsequent papers will focus on the human ecology of the dike-pond system, the ecological basis for system integration, and the results and implications of experiments and trials for increasing the productivity of and the economic rate of return from the system.  相似文献   

8.
Abstract

This paper reviews the development of international collaboration in the availability of global data and processing abilities in the environmental field, beginning in 1957 with tie pioneering activities of the World Data Centres. Considerable progress has been made, particularly through the availability of satellite data, but there are considerable shortcomings in these achievements, arising from the isolated nature of many developments, the difficulties of integrating different sources and weaknesses in the top-down approach. There are now attempts to develop a complementary bottom-up approach, notably through the Global Change Diskette Project Developments in hardware, such as the widespread availability of compatible personal computers operating on MS-DOS and UNIX systems; and easier storage on compact disks, and in software, through access to low-cost and public-domain software such as GRASS and IDRISI, are helping but improved collaboration is needed, in which existing institutions such as the World Data Centers have a major part to play.  相似文献   

9.
Reducing poverty in rural areas of developing countries requires sustained and sustainable increases in agricultural water productivity. However, aside from traditional measures of precipitation, little is known about water available to farmers or how productively they use it. We present a crop-water productivity index (a ratio of the value of annual crop production to a dimensionless potential water availability index) for large water basins using readily available low-resolution data. The index is transferable, permits direct inter-basin comparisons, and is simple to calculate. We calculate the index for each municipality in the São Francisco river basin in Brazil. No clear patterns linking water availability and value of agricultural output are evident, even though clusters of municípios with high- and low-crop-water productivity emerge, and the former may be useful in guiding policies aimed at increasing water productivity. Finally, analyses of the effects of information uncertainty on the crop-water productivity index suggest that the returns to agricultural investments in certain places in the São Francisco river basin are more risky than others. Improvements in data quality and quantity can help refine estimates of the index and reduce their uncertainty.  相似文献   

10.
11.
This article tests the explanatory power and interactions among five alternative explanations of environmental knowledge: (1) local information availability, (2) neighborhood characteristics, (3) environmental attitudes, (4) personal empowerment, and (5) information seeking. Using random forest and conditional inference trees, the article analyzes survey responses and finds that attitudes about personal empowerment and frequent information seeking are the strongest predictors of knowledge. The study offers random forest and conditional inference trees as statistical tools for complex data sets and studies that test hypotheses generated from multiple theories. We discuss the influence of knowledge differences over inclusive sustainability discussions.  相似文献   

12.
Numerical classification and ordination techniques are used to examine compositional variability in 112 stands of mesophytic upland forest in the eastern United States from data published by Braun (1950). Five forest types are identified and used to interpret ordination results. Two prominent environmental gradients account for much of the compositional variability in the data set: along the first ordination axis a microclimate gradient reflects increasing soil moisture availability and cold stress from dry uplands to northern hardwood sites; along the second ordination axis, a soil fertility gradient segregates hemlock coves and dry uplands, both of which are characteristically found on shallow, nutrient-poor soils, from the other forest types. The efficacy of combining numerical classification and ordination techniques for analyzing and interpreting patterns in ecological data is underscored by these results.  相似文献   

13.
Classifications of urban settlements have traditionally used total employment data in place of basic (export-oriented) employment data. While urban analysis agree upon the superiority of basic employment data for these classifications, usually only total employment data are available. This paper uses the Arizona Community Data Set, a unique survey-generated body of information that describes the major economic characteristics of numerous Southwestern communities and includes both basic and total employment data, to explore the extent to which misclassification results when using total employment data.  相似文献   

14.
根据2005年厦门海洋工程勘察设计院对青兰山-福建炼油厂海底管线和污水排海管线海上路由调查资料,对30个样品9个环境因子数据的综合分析和数理统计,论述了环境因子的存在特征,揭示了某些因子之间的相关关系和共生组合.对样品进行Q型因子分析,显示出30个样品按腐蚀性大小,分为3个点群.通过评价指标得分得出:就本研究区而言,东部区域腐蚀性较强.通过比对分析发现:本海区底质环境优于台湾海峡西部其他海域,较适合海底工程建设.该研究结果对海底工程建设具有指标意义.  相似文献   

15.
One common problem with geographic data is that, for a specific geographic event, only occurrence information is available; information about the absence of the event is not available. We refer to these specific types of geospatial data as geographic one-class data (GOCD). Predicting the potential spatial distributions that a particular geographic event may occur from GOCD is difficult because traditional binary classification methods that require availability of both positive and negative training samples cannot be used. The objective of this research is to define GOCD and propose novel approaches for modelling potential spatial distributions of geographic events using GOCD. We investigate the effectiveness of one-class support vector machine (OCSVM), maximum entropy (MAXENT) and the newly proposed positive and unlabelled learning (PUL) algorithm for solving GOCD problems using a case study: species distribution modelling from synthetic data. Our experimental results indicate that generally OCSVM, MAXENT and PUL are effective in modelling the GOCD. Each method has advantages and disadvantages, but PUL seems to be the most promising method.  相似文献   

16.
Differences in the reporting units of data from diverse sources and changes in units over time are common obstacles to analysis of areal data. We compare common approaches to this problem in the context of changes over time in the boundaries of U.S. census tracts. In every decennial census, many tracts are split, consolidated, or changed in other ways from the previous boundaries to reflect population growth or decline. We examine two interpolation methods to create a bridge between years, one that relies only on areal weighting and another that also introduces population weights. Results demonstrate that these approaches produce substantially different estimates for variables that involve population counts, but they have a high degree of convergence for variables defined as rates or averages. Finally, the article describes the Longitudinal Tract Database (LTDB), through which we are making available public-use tools to implement these methods to create estimates within 2010 tract boundaries for any tract-level data (from the census or other sources) that are available for prior years as early as 1970.  相似文献   

17.
Gauging data are available from numerous streams throughout Australia, and these data provide a basis for historical analysis of geomorphic change in stream channels in response to both natural phenomena and human activities. We present a simple method for analysis of these data, and a brief case study of an application to channel change in the Tully River, in the humid tropics of north Queensland. The analysis suggests that this channel has narrowed and deepened, rather than aggraded: channel aggradation was expected, given the intensification of land use in the catchment, upstream of the gauging station. Limitations of the method relate to the time periods over which stream gauging occurred; the spatial patterns of stream gauging sites; the quality and consistency of data collection; and the availability of concurrent land-use histories on which to base the interpretation of the channel changes.  相似文献   

18.
This paper describes mean grain-size data from the 137Cs- and 210Pb-dated sediment core BS-3 (33-cm long) recovered from Jinheung Pond, located in the southwestern part of the Korean Peninsula. Grain-size analysis of the Jinheung Pond sediments shows a clear signal for changes in annual precipitation over the past 60 years. Instrumental records of annual precipitation (AP) and the annual summation of the precipitation of >50 mm per day (AP50), which reflects the energy available for sediment transport, correlate well with the mean grain-size distributions measured in the core. The most plausible mechanism for this response in mean grain size is variations in the annual amount and intensity of precipitation. Heavy precipitation enhances soil erosion over the catchment area and increases the transport capacity of streams and rivers. Thus, coarser mean grain size should reflect higher precipitation, and smaller mean grain size should reflect lower rainfall. In the data from core BS-3, however, grain-size peaks attributed to increased annual precipitation are not prominent. This is because a dam prevents removal of fine particles from the pond via the outflow. Therefore, the mean grain-size value represents somewhat larger sediments together with fine clays. The results of this study show that sediments of dammed lakes and ponds are well suited for high-resolution environmental investigations, especially for records of changes in precipitation over time.  相似文献   

19.
Abstract

Recent changes in information technology offer the opportunity to explore alternative architectures for geographical information systems (GIS) which might better support advanced applications. This paper describes the architecture and implementation of the environmental decision support system (EDSS), a prototype GIS tool kit. The architecture is based on a simple yet powerful systems model using only data collections, views and operations as the basic entity types. The design of the user interface, data management and data analysis within the model are outlined, with particular emphasis on the advanced facilities for which implementation is simplified by the architecture. A prototype applications system, BANKSIA, is also described.  相似文献   

20.
The paper describes a land use conflict in the coastal zone of Western Norway. The author shows that such conflicts arise due to lack of environmental and conservation data. To avoid land use conflicts, it is inadequate to consider economic and technical aspects, only. It is shown how landscape planning must include several land use interests to be successful. The methods of landscape geography are considered to be useful towards this end.  相似文献   

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