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61.
The quality assessment of coastal waters of a tourist resort, on the basis of water quality criteria was attempted by using different quantitative approaches. Five variables related to eutrophication, that is nitrate, nitrite, ammonia, phosphate and chl were analyzed. Graphical methods were applied to all variables as well as unvariate statistical methods on the total inorganic nitrogen. Cluster analysis based on the five variables was also applied as an approach for numerical classification of the coastal waters. Comparison between the unvariate and multivariate methods used, was attempted to assess the validity of the procedures. The suitability of the methods used in coastal water management is also discussed.  相似文献   
62.
Investigation into local peoples’ perceptions can produce useful information that could be incorporated into the decision-making process to help resolve environmental problems. Within the arena of land degradation, a number of studies have also been conducted to explore local peoples’ views of the problem. However, the perceptions of land-degrading practices of the general public have so far not been actively solicited. This study aimed to contribute to this area of research by adopting the psychometric scaling technique to empirically explore the lay public’s ecological risk perceptions of land-degrading activities in Minqin County in Gansu Province, northern China. The primary data were collected via a questionnaire survey (n = 1,138) administered between 14 and 31 December 2002. The major findings of the survey were: (1) Respondents perceived the ecological risks posed by different land-degrading activities to be different. (2) There was a considerable incongruence in the way in which mining of groundwater was conceived by experts and laymen, respectively. (3) Respondents were pretty unsure of expert knowledge. (4) Respondents’ ecological risk perceptions were significantly affected by their personal attributes. As far as the policy implications of these findings are concerned, this study accentuates that we must be aware of, and involved in, the environmental perceptions of the lay public in order to succeed in guiding any human-environment tensions along more sustainable trajectories and navigating the transition to sustainability.  相似文献   
63.
The role of indigenous knowledge in increasing context specificity and exposing blind spots in scientific understanding is widely evidenced in disaster studies. This paper aims to structure the processes that shape indigenous knowledge production and its optimisation using the case of floods. An inductive analytical approach is applied among riparian indigenous communities (focus on the Bayira) of the Rwenzori region of Uganda where plenty of indigenous flood practices have been recorded. Indigenous knowledge of floods is found to be based on intimate comprehension of local hydrometeorological regularities. Insofar as these regularities follow natural dynamics, indigenous socio-epistemic processes are noted to be consistent with the laws of nature. Coupled with regular open sociocultural deliberations, the conceptualisation of hydrometeorological regularities induces an indigenous ontology and empiricist epistemology. This, together with the techniques used, is the driver of crucial epistemic virtues which enable indigenous knowledge to provide disaster solutions that are adapted, pragmatic, and holistic.  相似文献   
64.
We investigate the correlation between stress-related compounds produced by corals of the Great Barrier Reef (GBR) and local atmospheric properties—an issue that goes to the core of the coral ecosystem’s ability to survive climate change. We relate the variability in a satellite decadal time series of fine-mode aerosol optical depth (AOD) to a coral stress metric, formulated as a function of irradiance, water clarity, and tide, at Heron Island in the southern GBR. We found that AOD was correlated with the coral stress metric, and the correlation increased at low wind speeds, when horizontal advection of air masses was low and the production of non-biogenic aerosols was minimal. We posit that coral reefs may be able to protect themselves from irradiance stress during calm weather by affecting the optical properties of the atmosphere and local incident solar radiation.  相似文献   
65.
Acid weathered soils often require lime and fertilizer application to overcome nutrient deficiencies and metal toxicity to increase soil productivity. Slow-pyrolysis chicken manure biochars, produced at 350 and 700°C with and without subsequent steam activation, were evaluated in an incubation study as soil amendments for a representative acid and highly weathered soil from Appalachia. Biochars were mixed at 5, 10, 20, and 40 g kg into a Gilpin soil (fine-loamy, mixed, active, mesic Typic Hapludult) and incubated in a climate-controlled chamber for 8 wk, along with a nonamended control and soil amended with agronomic dolomitic lime (AgLime). At the end of the incubation, soil pH, nutrient availability (by Mehlich-3 and ammonium bicarbonate diethylene triamine pentaacetic acid [AB-DTPA] extractions), and soil leachate composition were evaluated. Biochar effect on soil pH was process- and rate-dependent. Biochar increased soil pH from 4.8 to 6.6 at the high application rate (40 g kg), but was less effective than AgLime. Biochar produced at 350°C without activation had the least effect on soil pH. Biochar increased soil Mehlich-3 extractable micro- and macronutrients. On the basis of unit element applied, increase in pyrolysis temperature and biochar activation decreased availability of K, P, and S compared to nonactivated biochar produced at 350°C. Activated biochars reduced AB-DTPA extractable Al and Cd more than AgLime. Biochar did not increase NO in leachate, but increased dissolved organic carbon, total N and P, PO, SO, and K at high application rate (40 g kg). Risks of elevated levels of dissolved P may limit chicken manure biochar application rate. Applied at low rates, these biochars provide added nutritional value with low adverse impact on leachate composition.  相似文献   
66.
The environmental risks caused by the use of fluoroquinolone antibiotics in human therapeutics and animal husbandry are associated with their persistence and (bio)accessibility in soil. To assess these aspects, we administered difloxacin to pigs and applied the contaminated manure to soil. We then evaluated the dissipation and sequestration of difloxacin in soil in the absence and presence of plants within a laboratory trial, a mesocosm trial, and a field trial. A sequential extraction yielded antibiotic fractions of differing binding strength. We also assessed the antibiotic's effects on nitrogen turnover in soil (potential nitrification and denitrification). Difloxacin was hardly (bio)accessible and was very persistent under all conditions studied (dissipation half-life in bulk soil, >217 d), rapidly forming nonextractable residues. Although varying environmental conditions did not affect persistence, dissipation was accelerated in soil surrounding plant roots. Effects on nitrogen turnover were limited due to the compound's strong binding and small (bio)accessibility despite its persistence.  相似文献   
67.
Quantitative inference from environmental contaminant data is almost exclusively from within the classic Neyman/Pearson (N/P) hypothesis-testing model, by which the mean serves as the fundamental quantitative measure, but which is constrained by random sampling and the assumption of normality in the data. Permutation/randomization-based inference originally forwarded by R. A. Fisher derives probability directly from the proportion of the occurrences of interest and is not dependent upon the distribution of data or random sampling. Foundationally, the underlying logic and the interpretation of the significance of the two models vary, but inference using either model can often be successfully applied. However, data examples from airborne environmental fungi (mold), asbestos in settled dust, and 1,2,3,4-tetrachlorobenzene (TeCB) in soil demonstrate potentially misleading inference using traditional N/P hypothesis testing based upon means/variance compared to permutation/randomization inference using differences in frequency of detection (Δf d). Bootstrapping and permutation testing, which are extensions of permutation/randomization, confirm calculated p values via Δf d and should be utilized to verify the appropriateness of a given data analysis by either model.  相似文献   
68.
A slurry method of induction of test particles into a high-temperature, high-pressure gaseous flow stream is presented. The method can provide accurate control and sensitive adjustment of the particle feed and can have an ameliorative effect on particle statistics.  相似文献   
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