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101.
Recently, a number of “Payment for Watershed Services” programs have aimed to engage private landowners in watershed stewardship initiatives by offering financial incentives for adopting watershed best management practices. However, a growing field of research suggests that financial incentives alone may be of limited utility to encourage widespread and long-standing behavior change, and other policy tools may be required. This research examines how attitudes may influence enrollment in watershed stewardship programs to shed light the application of incentive, capacity building, and symbolic policy tools. We distributed a questionnaire to rural landowners in the Clackamas River watershed, OR, and received 281 valid responses (29% response rate). We found that attitudes associated with trust, ecological understanding, and technical capacity played more fundamental roles compared with financial considerations. We interpret these findings by evaluating the likely efficacy of various policy tools, and stress the importance of engaging landowners by building capacity and trust. 相似文献
102.
A previously unsuspected source of fuel for the global firestorm recorded by soot in the Cretaceous–Tertiary impact layer may have resided in methane gas associated with gas hydrate in the end-Cretaceous seafloor. End-Cretaceous impact-generated shock and megawaves would have had the potential to initiate worldwide oceanic methane gas blow-outs from these deposits. The methane would likely have ignited and incompletely combusted. This large burst of methane would have been followed by longer-term methane release as a part of a positive thermal feedback in the disturbed ocean-atmosphere system. 相似文献
103.
Priv.-Doz. Dr. Max Weber 《Pure and Applied Geophysics》1960,47(1):12-16
Zusammenfassung Es wird die Methode der fortgesetzten Auslage in der Refraktionsseismik allgemein behandelt, und dazu werden einige Beispiele gegeben.
Summary The method of continuous profiling in the refraction seismic is generally treated and some examples are given.相似文献
104.
MIKE WALKER Martin J. Head John Lowe Max Berkelhammer Svante Bj
rck Hai Cheng Les C. Cwynar David Fisher Vasileios Gkinis Antony Long Rewi Newnham Sune Olander Rasmussen Harvey Weiss 《第四纪科学杂志》2019,34(3):173-186
The Holocene, which currently spans ~11 700 years, is the shortest series/epoch within the geological time scale (GTS), yet it contains a rich archive of evidence in stratigraphical contexts that are frequently continuous and often preserved at high levels of resolution. On 14 June 2018, the Executive Committee of the International Union of Geological Sciences formally ratified a proposal to subdivide the Holocene into three stages/ages, along with their equivalent subseries/subepochs, each anchored by a Global boundary Stratotype Section and Point (GSSP). The new stages are the Greenlandian (Lower/Early Holocene Subseries/Subepoch) with its GSSP in the Greenland NGRIP2 ice core and dated at 11 700 a b2k (before 2000 CE); the Northgrippian (Middle Holocene Subseries/Subepoch) with its GSSP in the Greenland NGRIP1 ice core and dated at 8236 a b2k; and the Meghalayan (Upper/Late Holocene Subseries/Subepoch) with its GSSP in a speleothem from Mawmluh Cave, north‐eastern India, with a date of 4250 a b2k. We explain the nomenclature of the new divisions, describe the procedures involved in the ratification process, designate auxiliary stratotypes to support the GSSPs and consider the implications of the subdivision for defining the Anthropocene as a new unit within the GTS. 相似文献
105.
Interstellar transfer of planetary microbiota 总被引:2,自引:0,他引:2
106.
107.
108.
Max Pettini Samantha A. Rix Chuck C. Steidel Matthew P. Hunt Alice E. Shapley Kurt L. Adelberger 《Astrophysics and Space Science》2002,281(1-2):461-466
Recent advances in instrumentation and observing techniques have made it possible to begin to study in detail the stellar
populations and the interstellar media of galaxies at redshift z = 3, when the universe was still in its ‘teen years’. I illustrate recent progress in this field with the latest observations
of the gravitationally lensed galaxy MS 1512- cB58.
This revised version was published online in September 2006 with corrections to the Cover Date. 相似文献
109.
Using Ontologies for Integrated Geographic Information Systems 总被引:13,自引:0,他引:13
Frederico T. Fonseca Max J. Egenhofer Peggy Agouris & Gilberto Câmara 《Transactions in GIS》2002,6(3):231-257
Today, there is a huge amount of data gathered about the Earth, not only from new spatial information systems, but also from new and more sophisticated data collection technologies. This scenario leads to a number of interesting research challenges, such as how to integrate geographic information of different kinds. The basic motivation of this paper is to introduce a GIS architecture that can enable geographic information integration in a seamless and flexible way based on its semantic value and regardless of its representation. The proposed solution is an ontology-driven geographic information system that acts as a system integrator. In this system, an ontology is a component, such as the database, cooperating to fulfill the system's objectives. By browsing through ontologies the users can be provided with information about the embedded knowledge of the system. Special emphasis is given to the case of remote sensing systems and geographic information systems. The levels of ontologies can be used to guide processes for the extraction of more general or more detailed information. The use of multiple ontologies allows the extraction of information in different stages of classification. The semantic integration of aerial images and GIS is a crucial step towards better geospatial modeling. 相似文献
110.
Public participation geographic information systems (PPGIS) are an increasingly important tool for collecting spatial information about the social attributes of place. The availability of Internet‐based options for implementing PPGIS presents new opportunities for increased efficiency and new modes of access. Here we used a mixed‐mode approach to evaluate paper versus Internet mapping methods for the same PPGIS survey in Wyoming. We compared participant characteristics, mapping participation, and the spatial distribution of mapped attributes between participants who responded to the paper versus Internet option. The response rate for those who completed the paper version of the survey was nearly 2.5 times the response rate of the Internet version. Paper participants also mapped significantly more places than did Internet participants (43 vs. 18). Internet participants tended to be younger, more likely to have a college degree, and had lived in the region for less time than paper participants. For all but one attribute there was no difference in the spatial distribution of places mapped between Internet and paper methods. Using a paper‐based PPGIS survey resulted in a higher response rate, reduced participant bias, and greater mapping participation. However, survey mode did not influence the spatial distribution of the PPGIS data. 相似文献