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71.
Crowdsourcing is a popular means of acquiring data, but the use of such data is limited by concerns with its quality. This is evident within cartography and geographical sciences more generally, with the quality of volunteered geographic information (VGI) recognized as a major challenge to address if the full potential of citizen sensing in mapping applications is to be realized. Here, a means to characterize the quality of volunteers, based only on the data they contribute, was used to explore issues connected with the quantity and quality of volunteers for attribute mapping. The focus was on data in the form of annotations or class labels provided by volunteers who visually interpreted an attribute, land cover, from a series of satellite sensor images. A latent class model was found to be able to provide accurate characterisations of the quality of volunteers in terms of the accuracy of their labelling, irrespective of the number of cases that they labelled. The accuracy with which a volunteer could be characterized tended to increase with the number of volunteers contributing but was typically good at all but small numbers of volunteers. Moreover, the ability to characterize volunteers in terms of the quality of their labelling could be used constructively. For example, volunteers could be ranked in terms of quality which could then be used to select a sub-set as input to a subsequent mapping task. This was particularly important as an identified subset of volunteers could undertake a task more accurately than when part of a larger group of volunteers. The results highlight that both the quantity and quality of volunteers need consideration and that the use of VGI may be enhanced through information on the quality of the volunteers derived entirely from the data provided without any additional information.  相似文献   
72.
Connectivity initiatives typically require conservation action on private lands as a complement to public reserve systems, so they are more likely to succeed if underpinned by knowledge of the social factors influencing landholders' participation. Using a combination of social survey and market research techniques, we identify spatially referenced landholder segments. Using a number of behavioral and attitudinal constructs, including three psychographic constructs not previously used for identifying segments—sense of place, lifestyle motives, and nature values—we identify three lifestyler and two farmer segments, and show that the characteristics of lifestyler segments are more nuanced than previously thought. Preferences for four corridor connectivity initiatives are found to differ across landholder segments, which indicates the importance using a targeted approach for designing connectivity conservation programs. The results highlight the importance for achieving corridor connectivity of the Blue Collar Lifestyler segment, a lower sociodemographic segment not previously identified in the literature.  相似文献   
73.
In this paper we address the revival of interest in recent years in the relevance of geographical research and highlight problems of politicization faced by researchers through cases of policy-oriented research in the UK and Belgium. We argue that geographers should be aware of the possibilities and constraints for critical engagement in the context of policy-oriented research. We identify at least two important opportunities for researchers to avoid clientelistic relationships with contractors and enhance their political relevance. First, researchers can stick to letter of the contract and maintain academic standards while at the same time interpreting their tasks according to their own ethical and political judgements. Second, relevance can be increased by forming alliances within and beyond the formal hierarchies of the state and the academy. The identification and utilization of these 'spaces of relevance' can be seen as the first step towards an approach that strategically seeks a balance between societal engagement on the one hand and contractual obligations, policy relevance and academic standards on the other.  相似文献   
74.
ABSTRACT

Obtaining useful geographic information from the flood of user-generated geographic content (UGGC) data is of significant interest, but comes with challenges in an age of crowdsourcing. To address this issue, we adopt Maslow’s model of human needs to frame UGGC. Synthesizing across literature about volunteered geographic information and participatory GIS, we present a conceptual framework for characterizing collection of UGGC. The framework is composed of multiple dimensions and levels that include perspectives about motivations, participatory methods, and participants. We also articulate four levels of participants (stakeholders, core-engaged participants, semi-core-engaged participants, and engaged citizens) together with four work principles (communication, cooperation, coordination, and collaboration). Finally, a case study describes an example we use to evaluate the conceptual framework for its suitability in design of a UGGC system. We conclude by reflecting on how and why this framework offers a valuable perspective for deriving useful geographic information and offer future research directions.  相似文献   
75.
To accurately document the accelerated changes in biodiversity, scientists need an accurate historic baseline to which to compare the current state of a locale. These historic baselines are hard to come by, and specifically in the coastal principality of Asturias (northern Spain), biodiversity information before 1980 is scarce, fragmented, or entirely lacking. However, most families still keep old photographs, and we wondered if these historic documentations of the environment could provide missing baseline biodiversity data. We conducted a case study asking volunteers to find old family photographs, then return to the same place to retake the photograph from the same perspective. We compiled these photographs and analyzed the changes in biodiversity indices between the past and present. Thus, we quantified diversity changes in the region over the last century.  相似文献   
76.
Climate engineering has received increasing attention, but its discussion has remained on the sidelines of mainstream climate policy. The policy relevance of this previously exotic option is poised to rise because of the gap between the temperature goals of the Paris Agreement and slow global mitigation efforts. It is therefore crucial to understand the risks and benefits of the proposed schemes, and the social implications of policy choices. Assessment of the risks and benefits of solar geoengineering strongly depends on scenarios, but previous scenarios have not reflected the full range of social choices. In light of concerns over risks, a newer set of scenarios is desirable, which represents both uncertainties and social choices more fully. Borrowing and extending lessons from recent literature on the new community climate scenario process, we envision a possible scenario-building process that combines interdisciplinary scholarship with the involvement of stakeholders and citizens. The resultant scenarios would better characterize uncertainties of, and policy choices for, solar geoengineering, and foster critical appraisal of its risks and benefits. Such societal choices might include not only total ban and large-scale deployment, but also limited deployment, which has received less attention in the scenario literature. The interaction between scenario and governance research would be able to highlight the central issues at stake, including ethical, social, and political dimensions.

Key policy insights

  • A more comprehensive assessment of solar geoengineering is necessary to evaluate its risks and benefits, necessitating new scenario research

  • It is crucial to reflect the full span of policy choices and uncertainties with interdisciplinary collaboration in such scenarios

  • Such societal choices might include not only total ban and large-scale deployment, but also limited deployment, which has received less attention in the scenario literature

  • Participatory scenario research would enable incorporating the concerns and opinions of stakeholders and citizens in scenario creation

  相似文献   
77.
This article discusses the ways in which the impacts of “geographic” community-based learning and research (CBLR) transcend the boundaries of the discipline of geography and also contribute to the practice and theory of civic engagement. I consider mapping and spatial thinking as a unique method for encouraging faculty, students, and community to engage in community partnerships. Drawing from several years of experience of teaching a CBLR course in an interdisciplinary setting, I highlight the role of geography in promoting community engagement. Geographic perspectives and methods can transform outreach or service models of community engagement into meaningful community partnerships that build and sustain a reciprocal relationship between university and community. I articulate three levels of geographic intervention that geographers need to attend to: theoretical, pedagogical, and institutional interventions on civic engagement.  相似文献   
78.
A crucial element in the foundation of geographic training is field experience and the opportunity to learn how to interpret the landscape. This element of the geographer's background provides a link between theory and reality. To enhance that experience, a place-based project focusing on civic engagement increases the student's understanding of geographic concepts, tools, and techniques while providing a service to a local community. This research proposes a model for developing classroom field experience that engages the student-researchers with a local community to address a community-based issue. A case study examining downtown parking in Laramie, Wyoming, is presented. The case study demonstrates how field experience, civic engagement, and collaborative learning can be incorporated into a classroom  相似文献   
79.
Governments are increasingly supporting initiatives to address plastic pollution, but efforts are largely opportunistic or driven by national socio-political priorities. There is an urgent need to move away from piecemeal single product instruments (e.g. single use plastic bag taxes or plastic straw bans) to deliver system-wide strategies that minimise the most pervasive sources of plastic pollution. Developing a common understanding of a jurisdiction’s plastic waste stream and the solutions available to decision-makers is vital to build consensus across stakeholders and to align on an evidence-based portfolio of priority instruments.This paper presents the Plastic Drawdown framework as a boundary-spanning tool to quickly create a coherent, relevant, and credible analysis and visualisation for stakeholders of plastic waste, leakage hotspots and minimisation opportunities. Using a new plastic waste modelling framework with a consultative structure, Plastic Drawdown explores plastic waste and leakage over a ten-year period and assesses impacts of policy instruments on this projection. Plastic Drawdown is adaptable to the data poor environment typical of many countries and designed as a rapid assessment tool to support the decision making of governments operating in a highly resource-constrained context.The Maldives is used as a case study to show the utility of the tool, where it highlighted strategies with the potential to reduce leakage of plastic waste into the marine environment by up to 85% by 2030. Plastic Drawdown built the case for phasing out single-use plastic waste across the Maldives and supported the Government’s decision to set ambitious targets, as announced at the United Nations General Assembly in 2019.  相似文献   
80.
ABSTRACT

Streamflow data are important for river management and the calibration of hydrological models. However, such data are only available for gauged catchments. Citizen science offers an alternative data source, and can be used to estimate streamflow at ungauged sites. We evaluated the accuracy of crowdsourced streamflow estimates for 10 streams in Switzerland by asking citizens to estimate streamflow either directly, or based on the estimated width, depth and velocity of the stream. Additionally, we asked them to estimate the stream level class by comparing the current stream level with a picture that included a virtual staff gauge. To compare the different estimates, the stream level class estimates were converted into streamflow. The results indicate that stream level classes were estimated more accurately than streamflow, and more accurately represented high and low flow conditions. Based on this result, we suggest that citizen science projects focus on stream level class estimates instead of streamflow estimates.  相似文献   
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