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901.
902.
Predicting Opportunities for Greening and Patterns of Vegetation on Private Urban Lands 总被引:1,自引:1,他引:1
Troy AR Grove JM O'Neil-Dunne JP Pickett ST Cadenasso ML 《Environmental management》2007,40(3):394-412
This paper examines predictors of vegetative cover on private lands in Baltimore, Maryland. Using high-resolution spatial
data, we generated two measures: “possible stewardship,” which is the proportion of private land that does not have built
structures on it and hence has the possibility of supporting vegetation, and “realized stewardship,” which is the proportion
of possible stewardship land upon which vegetation is growing. These measures were calculated at the parcel level and averaged
by US Census block group. Realized stewardship was further defined by proportion of tree canopy and grass. Expenditures on
yard supplies and services, available by block group, were used to help understand where vegetation condition appears to be
the result of current activity, past legacies, or abandonment. PRIZM™ market segmentation data were tested as categorical
predictors of possible and realized stewardship and yard expenditures. PRIZM™ segmentations are hierarchically clustered into
5, 15, and 62 categories, which correspond to population density, social stratification (income and education), and lifestyle
clusters, respectively. We found that PRIZM 15 best predicted variation in possible stewardship and PRIZM 62 best predicted
variation in realized stewardship. These results were further analyzed by regressing each dependent variable against a set
of continuous variables reflective of each of the three PRIZM groupings. Housing age, vacancy, and population density were
found to be critical determinants of both stewardship metrics. A number of lifestyle factors, such as average family size,
marriage rates, and percentage of single-family detached homes, were strongly related to realized stewardship. The percentage
of African Americans by block group was positively related to realized stewardship but negatively related to yard expenditures. 相似文献
903.
Agri-environment programs aim to secure environmental and social stewardship services through payments to farmers. A critical
component of many agri-environment programs is an agri-environment index (AEI) used to quantify benefits and target investments.
An AEI will typically comprise multiple indicators, which are weighted and combined using a utility function, to measure the
benefit of investment options (e.g., projects, farms, regions). This article presents a review of AEIs with 11 case studies
from agri-environment programs in the United States, Australia, and the United Kingdom. We identify a generic procedure used
to define AEIs and explore the implications of alternative methodological approaches. We conclude that AEIs have become an
extremely important policy instrument and make suggestions for their improvement. 相似文献
904.
The microbiological and physico-chemical characteristics of the drinking water supplied by the Central Borehole at the University
of Benin, Ugbowo Campus were investigated. The investigation entailed assessment of the pH, turbidity, total suspended solids,
total dissolved solids, dissolved oxygen, temperature, salinity, conductivity, nitrate, nitrite, phosphate, sulphate, chloride,
N-nitroso compounds, cadmium, chromium, nickel, lead, zinc, manganese, iron, coliform count, BOD5 and COD of the water at the Central Borehole and at ten residential quarters. The assessment indicated that the water was
fit for drinking and other domestic applications. Results were also compared with WHO, EU and Nigeria FEPA standards. The
results showed that the pH values of the water (5.01–5.86) and total coliform count (1–2/100 ml) expressed as MPN were outside
the limits set by the WHO, EU and FEPA. The data also showed that the other water quality parameters assessed were within
WHO, EU and FEPA permissible limits. The results of ANOVA showed that significant changes occurred during distribution. 相似文献
905.
Analysis tools that combine large spatial and temporal scales are necessary for efficient management of wildlife species,
such as the burrowing owl (Athene cunicularia). We assessed the ability of Ripley’s K-function analysis integrated into a geographic information system (GIS) to determine changes in burrowing owl nest clustering
over two years at NASA Ames Research Center. Specifically, we used these tools to detect changes in spatial and temporal nest
clustering before, during, and after conducting management by mowing to maintain low vegetation height at nest burrows. We
found that the scale and timing of owl nest clustering matched the scale and timing of our conservation management actions
over a short time frame. While this study could not determine a causal link between mowing and nest clustering, we did find
that Ripley’s K and GIS were effective in detecting owl nest clustering and show promise for future conservation uses. 相似文献
906.
Lavee D 《Environmental management》2007,40(6):926-943
It has traditionally been argued that recycling municipal solid waste (MSW) is usually not economically viable and that only
when externalities, long-term dynamic considerations, and/or the entire product life cycle are taken into account, recycling
becomes worthwhile from a social point of view. This article explores the results of a wide study conducted in Israel in the
years 2000–2004. Our results reveal that recycling is optimal more often than usually claimed, even when externality considerations
are ignored.
The study is unique in the tools it uses to explore the efficiency of recycling: a computer-based simulation applied to an
extensive database. We developed a simulation for assessing the costs of handling and treating MSW under different waste-management
systems and used this simulation to explore possible cost reductions obtained by designating some of the waste (otherwise
sent to landfill) to recycling. We ran the simulation on data from 79 municipalities in Israel that produce over 60% of MSW
in Israel. For each municipality, we were able to arrive at an optimal method of waste management and compare the costs associated
with 100% landfilling to the costs born by the municipality when some of the waste is recycled. Our results indicate that
for 51% of the municipalities, it would be efficient to adopt recycling, even without accounting for externality costs. We
found that by adopting recycling, municipalities would be able to reduce direct costs by an average of 11%.
Through interviews conducted with representatives of municipalities, we were also able to identify obstacles to the utilization
of recycling, answering in part the question of why actual recycling levels in Israel are lower than our model predicts they
should be. 相似文献
907.
Merle Sowman Maria Hauck Lance van Sittert Jackie Sunde 《Environmental management》2011,47(4):573-583
A historical perspective on MPA identification and governance in South Africa reflects the continued influence of a top-down
and natural science-based paradigm, that has hardly changed over the past half century, despite the wealth of literature,
and a growing consensus, that advocates the need to adopt a more integrated and human-centered approach. Based on extensive
research in two coastal fishing communities, the paper highlights impacts and conflicts arising from this conventional approach
to MPA identification, planning and management. It argues that failure to understand the particular fishery system in all
its complexity, in particular the human dimensions, and involve resource users in planning and decision-making processes,
undermines efforts to achieve conservation and fisheries management objectives. The customary rights of local resource users,
and their food and livelihood needs in relation to marine resources, need to be acknowledged, prioritized and integrated into
planning and decision-making processes. Convincing ecologists, fisheries scientists and managers, that MPA success depends
on addressing the root causes of resource decline and incorporating social factors into MPA identification, planning and management,
remains a huge challenge in South Africa. 相似文献
908.
Adaptations in infrastructure may be necessitated by changes in temperature and precipitation patterns to avoid losses and maintain expected levels of service. A roster of adaptation strategies has emerged in the climate change literature, especially with regard to timing: anticipatory, concurrent, or reactive. Significant progress has been made in studying climate change adaptation decision making that incorporates uncertainty, but less work has examined how strategies interact with existing infrastructure characteristics to influence adaptability. We use a virtual testbed of highway drainage crossings configured with a selection of actual culvert emplacements in Colorado, USA, to examine the effect of adaptation strategy and culvert characteristics on cost efficiency and service level under varying rates of climate change. A meta-model approach with multinomial regression is used to compare the value of better climate change predictions with better knowledge of existing crossing characteristics. We find that, for a distributed system of infrastructural units like culverts, knowing more about existing characteristics can improve the efficacy of adaptation strategies more than better projections of climate change. Transportation departments choosing climate adaptation strategies often lack detailed data on culverts, and gathering that data could improve the efficiency of adaptation despite climate uncertainty. 相似文献
909.
910.
Raphael Abiodun Olawepo 《The Environmentalist》2008,28(2):108-122
Fish production and marketing are as old as the rural communities involved in the lucrative occupation in Badagry area of Lagos State, Nigeria. A random sampling of 200 fishermen using Participatory Rural Appraisal techniques (PRA) in five Badagry villages was used to explore coastal fishing and socio-economic development in the study area with a view to enhancing local productivity and sustainability. The findings show that an average fisherman in Badagry is aware of the resources available in his environment, and can affect productivity levels positively if given adequate incentives. There are two lessons from this study; one has to do with what PRA tells us about the fishing community, the other is the importance of facilitators that have, amongst other things, good listening skills. The experience also revealed that field workers’ ability to listen and learn from local fishermen was a critical factor in collecting in-depth information that could be used for rural community planning. 相似文献