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61.
A Review of the Elements of Human Well-Being with an Emphasis on the Contribution of Ecosystem Services 总被引:7,自引:0,他引:7
Natural ecosystems perform fundamental life-support services upon which human civilization depends. However, many people believe that nature provides these services for free and therefore, they are of little or no value. While we do not pay for them, we pay significantly for their loss in terms of wastewater treatment facilities, moratoriums on greenhouse gases, increased illnesses, reduced soil fertility and losses in those images of nature that contribute to our basic happiness. Little is understood about the well-being benefits of the natural environment and its ecosystem services. The interwoven relationship of ecosystems and human well-being is insufficiently acknowledged in the wider philosophical, social, and economic well-being literature. In this article, we discuss an approach to examine human well-being and the interactions of its four primary elements-basic human needs, economic needs, environmental needs, and subjective well-being-and ecosystem services. 相似文献
62.
Using structural equation modeling to investigate relationships among ecological variables 总被引:2,自引:0,他引:2
Ziad A. Malaeb J. Kevin Summers Bruce H. Pugesek 《Environmental and Ecological Statistics》2000,7(1):93-111
Structural equation modeling is an advanced multivariate statistical process with which a researcher can construct theoretical concepts, test their measurement reliability, hypothesize and test a theory about their relationships, take into account measurement errors, and consider both direct and indirect effects of variables on one another. Latent variables are theoretical concepts that unite phenomena under a single term, e.g., ecosystem health, environmental condition, and pollution (Bollen, 1989). Latent variables are not measured directly but can be expressed in terms of one or more directly measurable variables called indicators. For some researchers, defining, constructing, and examining the validity of latent variables may be the end task of itself. For others, testing hypothesized relationships of latent variables may be of interest. We analyzed the correlation matrix of eleven environmental variables from the U.S. Environmental Protection Agency's (USEPA) Environmental Monitoring and Assessment Program for Estuaries (EMAP-E) using methods of structural equation modeling. We hypothesized and tested a conceptual model to characterize the interdependencies between four latent variables-sediment contamination, natural variability, biodiversity, and growth potential. In particular, we were interested in measuring the direct, indirect, and total effects of sediment contamination and natural variability on biodiversity and growth potential. The model fit the data well and accounted for 81% of the variability in biodiversity and 69% of the variability in growth potential. It revealed a positive total effect of natural variability on growth potential that otherwise would have been judged negative had we not considered indirect effects. That is, natural variability had a negative direct effect on growth potential of magnitude –0.3251 and a positive indirect effect mediated through biodiversity of magnitude 0.4509, yielding a net positive total effect of 0.1258. Natural variability had a positive direct effect on biodiversity of magnitude 0.5347 and a negative indirect effect mediated through growth potential of magnitude –0.1105 yielding a positive total effects of magnitude 0.4242. Sediment contamination had a negative direct effect on biodiversity of magnitude –0.1956 and a negative indirect effect on growth potential via biodiversity of magnitude –0.067. Biodiversity had a positive effect on growth potential of magnitude 0.8432, and growth potential had a positive effect on biodiversity of magnitude 0.3398. The correlation between biodiversity and growth potential was estimated at 0.7658 and that between sediment contamination and natural variability at –0.3769. 相似文献
63.
Over the past 50 years, human beings have influenced ecosystems more rapidly than at any similar time in human history, drastically
altering ecosystem functioning. Along with ecosystem transformation and degradation, a number of studies have addressed the
functioning, assessment and management of ecosystems. The concept of ecosystem services has been developed in the scientific
literature since the end of the 1970s. However, ecosystem service research has focused on certain service categories, ecosystem
types, and geographical areas, while substantial knowledge gaps remain concerning several aspects. We assess the development
and current status of ecosystem service research on the basis of publications collected from the Web of Science. The material
consists of (1) articles (n = 353) from all the years included in the Web of Science down to the completion of the Millennium Ecosystem Assessment and
(2) more recent articles (n = 687) published between 2006 and 2008. We also assess the importance of international processes, such as the Convention
on Biological Diversity, the Kyoto Protocol and the Millennium Ecosystem Assessment, as drivers of ecosystem service research.
Finally, we identify future prospects and research needs concerning the assessment and management of ecosystem services. 相似文献
64.
A novel biomonitoring system using microbial fuel cells 总被引:2,自引:0,他引:2
A novel biomonitoring system using microbial fuel cells for detecting the inflow of toxic substances into water systems has been developed for the purpose of on-site and on-line monitoring. The characteristics of electric current generation by electrochemically-active bacteria were conveniently monitored using a microbial fuel cell format and a computer-controlled potentiometer. When toxic substances (an organophosphorus compound, Pb, Hg, and PCBs) were added to the microbial fuel cell, rapid decreases in the current were observed. The inhibition ratios caused by inflow of these toxic substances (1 mg l(-1)) were 61%, 46%, 28% and 38%, respectively, when compared to the control, and generally increased in proportion to the addition time and concentration of toxic substances. When real wastewater was applied from a local wastewater treatment plant, more significant current decreases and higher inhibition ratios were observed following the introduction of toxic substances than in the laboratory tests. For example, the inhibition ratio was 76% on addition of a 1 mg l(-1) Cd and 1 mg l(-1) Pb mixture. Application of the microbial fuel cell for pollutant biomonitoring is discussed. 相似文献
65.
Smith LM Didonato EM Harwell LC Nestlerode JA Summers JK 《Environmental monitoring and assessment》2007,128(1-3):511-524
Using the approach established by EPA's Environmental Monitoring and Assessment Program (EMAP), a shoreline monitoring survey
was conducted in August and September 1999, encompassing the Florida Panhandle from Perdido Key, Florida to Port St. Joe,
Florida. The objective of this survey was to demonstrate the use of a probabilistic survey for monitoring and estimating the
condition of swimmable beach areas. Thirty stations were sampled using a probabilistic sampling design. Hydrographic data
were collected in addition to samples for water chemistry. Bacterial indicators, enterococci and fecal coliforms, were enumerated
from the water according to the EPA Beaches Environmental Assessment Closure and Health (BEACH) Program and Florida state
guidelines. Additional criteria for site condition included the presence or absence of primary and secondary dunes, anthropogenic
debris and vegetation. Based on EMAP evaluation guidelines and Florida state criteria, a baseline assessment of the condition
of the Gulf of Mexico beach resources surveyed is presented. 相似文献
66.
Determining the viability of marine protists using a combination of vital, fluorescent stains 总被引:1,自引:0,他引:1
Determining the viability of protists and small microzooplankton has long been a focus of studies in marine biology and ecology.
It is especially relevant in the issue of shipborne invasive species, and impending international guidelines and various national
regulations on the allowable concentrations of organisms in discharged ballast water have spurred the growth of an industry
that develops and manufactures ballast water management systems. The success of management systems and ability of ships to
meet ballast water discharge standards is determined by the number of viable organisms in treated water. Here, we propose
combining two vital, fluorescent stains (fluorescein diacetate [FDA] and 5-chloromethylfluorescein diacetate [CMFDA]) with
direct microscopic observation to enumerate viable organisms ≥10 and <50 μm in minimum dimension (nominally protists). This
approach was validated in four locations in the United States to determine the efficacy of the stains. Although the accuracy
of the stains varied by geographic location and the taxonomic composition of the planktonic assemblage, combining fluorescent
stains is a robust, powerful tool that can be optimized for the species present at each location. While this method was developed
for analyzing viable organisms in treated ballast water, it may also be used or adapted for any field of research that examines
a broad taxonomic range of autotrophic and heterotrophic plankton. 相似文献
67.
Angela Summers William Vogtmann Steven Smolen 《Journal of Loss Prevention in the Process Industries》2011,24(6):879-885
Most risk analysis methods rely on a qualitative judgment of consequence severity, regardless of the analysis rigor applied to the estimation of hazardous event frequency. Since the risk analysis is dependent on the estimated frequency and consequence severity of the hazardous event, the error associated with the consequence severity estimate directly impacts the estimated risk and ultimately the risk reduction requirements. Overstatement of the consequence severity creates excessive risk reduction requirements. Understatement results in inadequate risk reduction.Consistency in the consequence severity estimate can be substantially improved by implementing consequence estimation tools that assist PHA/LOPA team members in understanding the flammability, explosivity, or toxicity of process chemical releases. This paper provides justification for developing semi-quantitative look-up tables to support the team assessment of consequence severity. Just as the frequency and risk reduction tables have greatly improved consistency in the estimate of the hazardous event frequency, consequence severity tables can significantly increase confidence in the severity estimate. 相似文献
68.
69.
Deepak Sodhi Martin A. Abraham Jack C. Summers 《Journal of the Air & Waste Management Association (1995)》2013,63(3):352-356
Oxidation of formaldehyde over supported platinum catalyst produced CO2 as a major product and CO as a minor product under a wide range of Inlet concentrations and reaction temperatures. The temporal variation of CO yield proceeded through a maximum suggesting that it was produced as an intermediate in the pathway leading to CO2. CO selectivity (S co = y co/x HCHO) was maximized by operating at oxygen concentration below the stoichiometric point and at high reaction temperatures. A mechanism for formaldehyde oxidation is proposed which involves adsorption of formaldehyde followed by catalytic decomposition to CO and H2 and oxidation of the surface species; the rate limiting step apparently shifts from the decomposition at high oxygen concentration to the oxidation of surface species at low concentration. The rate expression was obtained from the postulated mechanism and found to be consistent with the experimental results. The maximum for the yield of CO provided a second method by which to confirm the postulated rate expression. 相似文献
70.
Parents adjust care in response to weather conditions and egg dehydration in a Neotropical glassfrog
Jesse R. J. Delia Aurelio Ramírez-Bautista Kyle Summers 《Behavioral ecology and sociobiology》2013,67(4):557-569
Parental hydration of terrestrially developing eggs has evolved repeatedly among frogs and is thought to buffer embryos from environmental variation. While many anurans offer relevant opportunities to study parental care, research on how parents respond to environmental variation and offspring conditions are lacking. In this study, we investigated the interrelationships of weather, embryo hydration demands, and parental provisioning in a wild population of the glassfrog Hyalinobatrachium (‘Centrolenella’) fleischmanni in Oaxaca, Mexico. We determined whether males modify parental behavior in response to changes in weather conditions that effect embryo dehydration, how variation in both weather and parental hydration affect egg water balance and embryonic mortality, and whether parental provisioning is related to the hydration levels of egg clutches. We found that male H. fleischmanni compensate for environmental variation in offspring conditions by adjusting the frequency of parental care in response to both weather and egg dehydration. Using a male removal experiment, we examined the function of paternal care and made comparisons with previous research, finding that both the adaptive value of parental care and flexibility in parental behavior are impacted by spatial and temporal conditions. We present observations that indicate a direct conflict between providing parental care and multiple matings. In summary, this research demonstrates that the variable frequency of paternal care in H. fleischmanni is a response to the fluctuating nature of the climate and resulting hydration requirements of embryos in combination with the allocation of effort to parental care versus mating activity. 相似文献