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Evaluation of conservation education programs can: (1) provide accountability in demonstrating a program's worth, (2) offer an opportunity for receiving feedback and improving programs, (3) further our understanding of the process of program development, and (4) promote conservation education by substantiating claims about its benefits. The Planning-Process-Product systems evaluation model provides feedback needed for making decisions about the development, implementation, and outcome of a program. Planning evaluation was useful in assessing the needs, goals, opportunities, and constraints of a number of programs in Costa Rica and Belize, such as a forestry education project and a zoo outreach program. It provided a basis for making planning decisions incorporating specific objectives, such as the reforestation of a region or a change in knowledge and attitudes in program participants. Process evaluation provided a Costa Rican sustainable development program with feedback during its implementation and enabled it to modify and improve its newsletter for local farmers and its ecology classes for school children. Product evaluation assessed project accomplishments, such as the $700,000 raised by the Children's Rainforest group and the 20 miles of riparian land under conservation management as part of the Belize Community Baboon Sanctuary project. Outcomes are compared with the programs original monetary or land management objectives to determine the success of the programs and to provide feedback for improvement.  相似文献   
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A review of wetland impacts authorized under the New Jersey Freshwater Wetlands Protection Act (FWPA) was conducted based on permitting data compiled for the period 1 July 1988 to 31 December 1993. Data regarding the acreage of wetlands impacted, location of impacts by drainage basin and watershed, and mitigation were analyzed. Wetland impacts authorized and mitigation under New Jersey's program were evaluated and compared with Section 404 information available for New Jersey and other regions of the United States.Under the FWPA, 3003 permits were issued authorizing impacts to 234.76 ha (602.27 acres) of wetlands and waters. Compensatory mitigation requirements for impacts associated with individual permits required the creation of 69.20 ha. (171.00 acres), and restoration of 16.49 ha (40.75 acres) of wetlands. Cumulative impacts by watershed were directly related to levels of development and population growth.The FWPA has resulted in an estimated 67% reduction [44.32 ha (109.47 acres) vs 136.26 ha (336.56 acres)] in annual wetland and water impacts when compared with Section 404 data for New Jersey. For mitigation, the slight increase in wetland acreage over acreage impacted is largely consistent with Section 404 data.Based on this evaluation, the FWPA has succeeded in reducing the level of wetland impacts in New Jersey. However, despite stringent regulation of activities in and around wetlands, New Jersey continues to experience approximately 32 ha (79 acres) of unmitigated wetland impacts annually. Our results suggest that additional efforts focusing on minimizing wetland impacts and increasing wetlands creation are needed to attain a goal of no net loss of freshwater wetlands.  相似文献   
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Based on intergroup theory, this study examined relationships among group characteristics (racioethnicity, gender, and level), contextual organizational unit characteristics (gender and racioethnic heterogeneity, resource support for women and racioethnic minorities) and perceptions of diversity climate by faculty at a large university. Compared to white men, white women and racioethnic minorities placed greater value on employer efforts to promote diversity, and held more favorable attitudes about the qualifications of women and racioethnic minorities. The study found that group rather than contextual organizational unit characteristics were more strongly related to diversity climate. However, the organizational unit characteristic, gender heterogeneity, was significantly related to valuing diversity. The greater the ratio of women in a unit, regardless of the respondents' gender, racioethnicity or level, the more favorable diversity activities were viewed. In addition, units whose allocation of resources to racioethnic minorities were perceived as insufficient by respondents were more likely to have members who valued diversity and held favorable perceptions toward the qualifications of racioethnic minorities. Implications for organizations and future research are offered.  相似文献   
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Many public programs have differential impacts on diverse parts of metropolitan areas. This fact has led analysts to use changes in land values as measures of the benefits of public programs. Using a model derived from theoretical urban economics, this paper demonstrates that changes in land values will only equal total benefits under very restrictive assumptions. Making concrete assumptions about consumer demand, the paper goes beyond previous work to consider the distributional impact of three different kinds of public programs: those which provide uniform benefits to every community, those which attempt to reduce intercommunity inequality, and those which generate improvements in only a subset of the region's towns.  相似文献   
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The National Oceanic Data Center (NODC) contains historical records from approximately 144,000 hydrographic stations in the North Atlantic. This data has been used by oceanographers to construct maps of point estimates of pressure, temperature, salinity and oxygen in the North Atlantic (Levitus (1994); Lozier et al. (1995)). Because data from any particular year are scarce, the previous maps have been for time-averaged values only. In addition, the maps have been reported without uncertainty estimates. This paper presents a Markov random field (MRF) analysis that can generate maps for specific time periods along with associated uncertainties. To estimate changes in oceanic properties over time previous oceanographic work has focused on differences between a few time periods each having many observations. Due to data scarcity this poses a severe restriction for both spatial and temporal coverage of climatic change. The MRF analysis provides a means for temporal modeling that does not require high data density at each time period. To demonstrate the usefulness of a MRF analysis of oceanic data we investigate the temporal variability along 24.5°N in the North Atlantic. Our results are compared to an earlier analysis (Parrilla et al. (1994)) where data from only three time periods was used. We obtain a more thorough understanding of the temperature change found by this previous study.  相似文献   
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