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161.
The long-term application of biosolids that periodically contained elevated metal concentrations has raised questions about potential effects on animal health. To address these concerns, we determined metal concentrations (As, Cd, Cu, Pb, Hg, Mo, Ni, Se, and Zn) in both soil and bermudagrass [Cynodon dactylon (L.) Pers.] forage from 10 fields in the following categories of biosolids application: six or more years (>6YR), less than six years (<6YR), and no applications (NS). Soil metal concentrations in all groups were similar to values reported for mineral soils in Georgia, and well below USEPA cumulative limits. Average metal concentrations in the forage were below the maximum tolerable level (MTL) for beef cattle, although two biosolids-amended fields in the >6YR group produced forage that was at or near the MTL for Cd and Mo, and one field in the <6YR group produced forage above the MTL for Cd. The Cu to Mo ratios in forage decreased with increasing time of sludge application, with the average in the >6YR group at a proposed 5:1 Cu to Mo ratio limit to protect ruminant health. Sulfur concentrations in the forage from all three groups was near the MTL of 4 g kg(-1). The study indicated that toxic levels of metals have not accumulated in the soils due to long-term biosolids application. Overall forage quality from the biosolids-amended fields was similar to that of commercially fertilized fields; however, due to the relatively high S and potential for a low Cu to Mo ratio, Cu supplements should be used to ensure ruminant health. 相似文献
162.
International declarations and charters have been produced to encourage and support higher education institutions (HEIs) to
address their environmental responsibilities. This paper discusses the results of a critical examination of a range of international
HEIs that have signed the global environmental Talloires Declaration. It also assesses the Talloires Secretariat (University
Leaders for a Sustainable Future, ULSF) and the extent to which this has been a primary stimulus. An international survey
was undertaken and the results presented in a discursive format in order to highlight key driving forces, barriers, and opportunities
for environmental responsibility in HEIs. Analysis reveals that they occur on two distinct and evolving levels: the macro
national framework level and the micro institutional framework level. Survey responses revealed that none of the HEIs have
an embedded institutional environmental culture and most did not have all the micro institutional mechanisms in place for
an integrated university-wide environmental response. Many of the institutional barriers to environmental responsibility occurred
as a result of this lack of strategy. The most significant institutional opportunity cited was enthusiastic individuals, particularly
those at senior management or directorate level, and these individuals were found to be a key driving force. Results also
showed that environmental reporting along the lines developed by the private sector is a flexible mechanism that can stimulate
progress internally and externally and can be cost effectively disseminated via the World Wide Web. Moreover the survey results
indicate that ULSF is not currently a primary stimulus for institution wide action. 相似文献
163.
Julia Jaenicke Henk Wösten Arif Budiman Florian Siegert 《Mitigation and Adaptation Strategies for Global Change》2010,15(3):223-239
Extensive degradation of Indonesian peatlands by deforestation, drainage and recurrent fires causes release of huge amounts
of peat soil carbon to the atmosphere. Construction of drainage canals is associated with conversion to other land uses, especially
plantations of oil palm and pulpwood trees, and with widespread illegal logging to facilitate timber transport. A lowering
of the groundwater level leads to an increase in oxidation and subsidence of peat. Therefore, the groundwater level is the
main control on carbon dioxide emissions from peatlands. Restoring the peatland hydrology is the only way to prevent peat
oxidation and mitigate CO2 emissions. In this study we present a strategy for improved planning of rewetting measures by dam constructions. The study
area is a vast peatland with limited accessibility in Central Kalimantan, Indonesia. Field inventory and remote sensing data
are used to generate a detailed 3D model of the peat dome and a hydrological model predicts the rise in groundwater levels
once dams have been constructed. Successful rewetting of a 590 km2 large area of drained peat swamp forest could result in
mitigated emissions of 1.4–1.6 Mt CO2 yearly. This equates to 6% of the carbon dioxide emissions by civil aviation in the European Union in 2006 and can be achieved
with relatively small efforts and at low costs. The proposed methodology allows a detailed planning of hydrological restoration
of peatlands with interesting impacts on carbon trading for the voluntary carbon market. 相似文献
164.
High genetic variability may increase metabolic efficiency and thus allows responding to environmental challenges as limits
to adaptation are approached. Therefore, it has been suggested that high genetic variability contributes strongly to the fitness
of an individual. Survival to high age may thus depend on high genetic variability, and genetically variable individuals may
have a higher survival rate to high ages in comparison to less variable sympatric conspecifics. Such a heterozygosity × age
relationship might be more readily detectable in stressful as compared to benign environments. For testing the relationship
between age and heterozygosity, we genetically analyzed 71 individuals of the frog species Rana perezi from a total of seven populations at 13 allozyme loci. The age of the individuals was determined by skeletochronology. We
found effects on age of both environment and allozyme heterozygosity, especially in populations with high stress regimes.
A significant heterozygosity × age relationship has so far rarely been shown in natural populations. The result of our analysis
suggests that more heterozygous individuals have a higher longevity and may be an important source of genetic variability
of a population, likely contributing to a stabilization of the effective population size. 相似文献
165.
根据2014年1月1日~6月30日江苏省13地级市监测PM2.5,PM10的数据,分析其污染特征.结果表明:全省PM2.5和PM10污染较严重,全省PM2.5,PM10超标率都分别达到78.33%,66.11%以上,尤其是细颗粒物的污染占主导地位;PM2.5/PM10的比值范围达到0.461 9~0.687 2,全省PM2.5和PM10之间存在显著的线性关系;PM2.5,PM10浓度时空分布特征为PM2.5:1月>3月>2月>5月>6月>4月,PM10:1月>5月>3月>6月>2月>4月;苏北>苏中>苏南. 相似文献
166.
Victoria F. Griffiths Joseph W. Bull Julia Baker E.J. Milner-Gulland 《Conservation biology》2019,33(1):76-87
Governments, businesses, and lenders worldwide are adopting an objective of no net loss (NNL) of biodiversity that is often partly achieved through biodiversity offsetting within a hierarchy of mitigation actions. Offsets aim to balance residual losses of biodiversity caused by development in one location with commensurate gains at another. Although ecological challenges to achieve NNL are debated, the associated gains and losses for local stakeholders have received less attention. International best practice calls for offsets to make people no worse off than before implementation of the project, but there is a lack of clarity concerning how to achieve this with regard to people's use and nonuse values for biodiversity, especially given the inevitable trade-offs when compensating biodiversity losses with gains elsewhere. This is particularly challenging for countries where poor people depend on natural resources. Badly planned offsets can exacerbate poverty, and development and offset impacts can vary across spatial-temporal scales and by location, gender, and livelihood. We conceptualize the no-worse-off principle in the context of NNL of biodiversity, by exploring for whom and how the principle can be achieved. Changes in the spatial and temporal distribution of biodiversity-related social impacts of a development and its associated offset can lead to social inequity and negatively impact people's well-being. The level of aggregation (regional, village, interest group, household, and individual) at which these social impacts are measured and balanced can again exacerbate inequity in a system. We propose that a determination that people are no worse off, and preferably better off, after a development and biodiversity offset project than they were before the project should be based on the perceptions of project-affected people (assessed at an appropriate level of aggregation); that their well-being associated with biodiversity losses and gains should be at least as good as it was before the project; and that this level of well-being should be maintained throughout the project life cycle. Employing this principle could help ensure people are no worse off as a result of interventions to achieve biodiversity NNL. 相似文献
167.
Grais RF Coulombier D Ampuero J Lucas ME Barretto AT Jacquier G Diaz F Balandine S Mahoudeau C Brown V 《Disasters》2006,30(3):364-376
Emergencies resulting in large-scale displacement often lead to populations resettling in areas where basic health services and sanitation are unavailable. To plan relief-related activities quickly, rapid population size estimates are needed. The currently recommended Quadrat method estimates total population by extrapolating the average population size living in square blocks of known area to the total site surface. An alternative approach, the T-Square, provides a population estimate based on analysis of the spatial distribution of housing units taken throughout a site. We field tested both methods and validated the results against a census in Esturro Bairro, Beira, Mozambique. Compared to the census (population: 9,479), the T-Square yielded a better population estimate (9,523) than the Quadrat method (7,681; 95% confidence interval: 6,160-9,201), but was more difficult for field survey teams to implement. Although applicable only to similar sites, several general conclusions can be drawn for emergency planning. 相似文献
168.
Genesio Mario da Rosa Julia Caetano Manfio Kauane Andressa Flach Alexandre Tiburski Neto Mathias Rezende Mahnke Arci Dirceu Wastowski 《环境质量管理》2023,32(4):301-310
The chrome (Cr) is a metal utilized in various industrial sectors and its investigation in the environment is necessary, for the Cr (III) contain aessential micronutrients in the human nourishment and the Cr (VI), on the other hand, is toxic. In the present work soil contamination with Cr was realized in drainagelysimetersset in concentrations of 0, 200, 400, 600, 800 and 1000 mg kg−1 of total Cr, with the intuition to determine the total Cr and Cr (VI) flux in leached water, in soil and in plants of lettuce (Lactuca sativa L.). In the lysimeters were cultivated four plants, in three cultivation circles. In the end of the cultivations was observed, that the total applied Cr leached in the soil, evidencing the Cr mobility in latossoil with simulant characteristics to the ones utilized in this paper. The Cr (VI) concentrations in the soil increased soon after the treatment applications, but tend to decrees in the time elapse, the same tendences were observed for the total Cr concentrations in the leached water. The Cr absorption by plants was related to the Cr disponibility in the soil, for the soil concentration and the plants decreased with time passing. The Cr mobility in the soil possibilitated the groundwater contamination presenting risks to the water quality and, consequently to public health. 相似文献
169.
In this study, we investigate association patterns of 249 bottlenose dolphin feeding groups off Sardinia Island (Italy) from
January 2000–May 2007 and describe how their association behaviour is related to their response to food patches created by
a marine fin fish farm. We also tested the hypothesis that dolphins have different social structures with different feeding
activities: Associations should decrease during opportunistic feeding behaviours as it is easier to capture prey, and cooperation
is not as necessary. Sixteen individually identified bottlenose dolphins were observed participating in both opportunistic
and not opportunistic feeding activities, with a mean of 30 ± 8 times and 9.6 ± 1 times, respectively. Bottlenose dolphins
show non-random social behaviour during feeding and this behaviour differs depending on their specific foraging activity.
Dolphin associations during feeding can be divided into three categories: acquaintances, affiliates, and feeding associates.
Association behaviour during fish farm feeding is consistent with our hypothesis that during opportunistic behaviours, benefits
from cooperation decrease, as it is easier to capture prey. Group size homogeneity in both feeding activities demonstrates
that the number of dolphins engaging in foraging is not necessarily related with cooperation levels. Moreover, an adult dolphin
may prefer to associate with a specific individual, independent of the sex, who shares the same foraging priorities. This
study is the first to show how aquaculture is not only directly affecting marine predators but could also indirectly affect
their social structure and behaviour. 相似文献
170.
Withers Paul J. A. Forber Kirsty G. Lyon Christopher Rothwell Shane Doody Donnacha G. Jarvie Helen P. Martin-Ortega Julia Jacobs Brent Cordell Dana Patton Myles Camargo-Valero Miller A. Cassidy Rachel 《Ambio》2020,49(5):1076-1089
Ambio - The chaotic distribution and dispersal of phosphorus (P) used in food systems (defined here as disorderly disruptions to the P cycle) is harming our environment beyond acceptable limits. An... 相似文献