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1.
Natural scientists are increasingly interested in social research because they recognize that conservation problems are commonly social problems. Interpreting social research, however, requires at least a basic understanding of the philosophical principles and theoretical assumptions of the discipline, which are embedded in the design of social research. Natural scientists who engage in social science but are unfamiliar with these principles and assumptions can misinterpret their results. We developed a guide to assist natural scientists in understanding the philosophical basis of social science to support the meaningful interpretation of social research outcomes. The 3 fundamental elements of research are ontology, what exists in the human world that researchers can acquire knowledge about; epistemology, how knowledge is created; and philosophical perspective, the philosophical orientation of the researcher that guides her or his action. Many elements of the guide also apply to the natural sciences. Natural scientists can use the guide to assist them in interpreting social science research to determine how the ontological position of the researcher can influence the nature of the research; how the epistemological position can be used to support the legitimacy of different types of knowledge; and how philosophical perspective can shape the researcher's choice of methods and affect interpretation, communication, and application of results. The use of this guide can also support and promote the effective integration of the natural and social sciences to generate more insightful and relevant conservation research outcomes. Una Guía para Entender la Investigación de Ciencias Sociales para las Ciencias Naturales Katie Moon  相似文献   
2.
The temporal variability and bioaccumulation dynamics of C12–25 n-alkanes, isoprenoids and unresolved aliphatic hydrocarbons (UCM) were studied in a detritivorous fish (Sábalo: Prochilodus lineatus) collected from 1999 to 2005 in the sewage impacted Buenos Aires coastal area. Fish muscles contain huge amounts of n-C12–25 (165 ± 93, 70 ± 48 or 280 ± 134 μg g−1, dry, fresh and lipid weight, respectively) and UCM (931 ± 560, 399 ± 288 and 1567 ± 802 μg g−1) reflecting the chronic bioaccumulation of fossil fuels from sewage particulates. On a temporal basis, lipid normalized aliphatic concentrations peaked by the end of 2001–2002 during the rainiest period over the last four decades (1750 vs. 1083 ± 4.6 mm in 1999, 2004 and 2005), reflecting an enhanced exposition due to massive anthropogenic fluxes from Metropolitan Buenos Aires in wet years. The hydrocarbon composition in fish muscles is enriched in n-C15–17 and isoprenoids relative to a fresh crude oil and settling particulates, with fresher signatures during the 2001–2002 maxima. Fish/settling material bioaccumulation factors (BAFs: 0.4–6.4 dry weight or 0.07–0.94 lipid-organic carbon) plotted against Kow showed a parabolic pattern maximizing at n-C14–18 and isoprenoids. The optimal bioaccumulation window corresponds to highly hydrophobic (loKow: 7.2–9.9), intermediate-size C14–18 n-alkanes and C15–20 isoprenoids (MW: 198–282; length: 17.9 to 25.4 Å) with melting points ranging from −19.8 to 28 °C. The uptake efficiency is inversely correlated to melting points and increased from 75% for n-C25 to above 90% for n-C14–15 and isoprenoids.  相似文献   
3.
Coastal fisheries provide staple food and sources of livelihood in Pacific Island countries, and securing a sustainable supply is recognised as a critical priority for nutrition security. This study sought to better understand the role of fish for Pacific Island communities during disasters and in disaster recovery. To evaluate community impacts and responses after natural disasters, focus group discussions were held with men and women groups at ten sites across Shefa, Tafea, Malampa and Sanma provinces in Vanuatu. The combined impacts of category 5 Tropical Cyclone Pam (TC-Pam) in March 2015 and prolonged El-Niño induced drought have had a profound impact across much of Vanuatu. Terrestrial systems had been disproportionately impacted with substantial shortages in drinking water, garden crops, cash crops and damage to infrastructure. Localized impacts were noted on marine environments from TC-Pam and the drought, along with an earthquake that uplifted reef and destroyed fishing grounds in Malampa province. Communities in Malampa and Shefa provinces also noted a crown-of-thorns outbreak that caused coral mortality. The significant reduction in terrestrial-based food and income generation capacity generally led to increased reliance on marine resources to cope and a shift in diets from local garden food to rice. However, limited market access, lack of fishing skills and technology in many sectors of the community reduced the capacity for marine resources to support recovery. A flexible management approach allowed protected areas and species to be utilized as reservoirs of food and income when temporarily opened to assist recovery. These findings illustrate that fish and fisheries management is at the center of disaster preparedness and relief strategies in remote Pacific Island communities. High physical capital (e.g. infrastructure, water tanks and strong dwellings) is key for disaster preparedness, but supporting community social capital for the purpose of natural resource management and human capital for diverse adaptation skills can also improve community resilience. Recognizing the humanitarian value that well managed fisheries resources and skilled fishers can play to disaster relief adds another dimension to the imperative of improving management of coastal fisheries and aligning policies across sectors.  相似文献   
4.

Background, Aim and Scope

The presence of heavy metals in wastewater is one of the main causes of water and soil pollution. The aim of the present study was to investigate the removal of Cd, Cu, Pb, Hg, Mn, Cr and Zn in urban effluent by a biological wastewater treatment, as well as to quantify the levels of As, Be, Cd, Cr, Cu, Fe, Hg, Mn, Ni, Pb, Sn, Tl, V and Zn in dewatering sludge from the Biological Wastewater Treatment Plant to Ribeirão Preto (RP-BWTP), Brazil.

Materials and Methods

Concentrations of Cd, Cr, Cu, Mn and Pb in wastewater and those of Ni in sludge were determined by atomic absorption spectrophotometry with graphite furnace atomization. Mercury concentrations in wastewater were measured by hydride generation atomic spectrophotometry, and Zn levels were determined by atomic absorption spectrophotometry using acetylene flame. In sludge, the levels of As, Be, Cd, Cr, Cu, Fe, Hg, Mn, Pb, Sn, Tl, V and Zn were determined by inductively coupled plasma-mass spectrometry.

Results

The percentages of removal efficiency (RE) were the following: Hg 61.5%, Cd 60.0%, Zn 44.9%, Cu 44.2%, PB 39.7%, Cr 16,5% and Mn 10.4%. In turn, the mean concentrations (mg/kg) of metals in dewatering sludge followed this increasing order: Tl (<0.03), Hg (0.31), Be (0.43), As (1.14), Cd (1.34), V (59.2), Pb (132.1), Sn (166.1), Cr (195.0), Mn (208.1), Ni (239.4), Cu (391.7), Zn (864.4) and Fe (20537).

Discussion

The relationship between metal levels in untreated wastewater, as well as the removal efficiency are in agreement with previous data from various investigators, It is important to note that metal removal efficiency is not only affected by metal ion species and concentration, but also by other conditions such as operating parameters, physical, chemical, and biological factors.

Conclusions

Metal values recorded for treated wastewater and sludge were within the maximum permitted levels established by the Environmental Sanitation Company (CETESB), São Paulo, Brazil.

Recommendations

There is an urgent need for the authorities who are responsible for legislation on sludge uses in agriculture of establishing safety levels for As, Be, Hg, Sn, Tl and V.

Perspectives

According to the current metal levels, RP-BWTP sludge might be used for agriculture purposes. However, for an environmentally safe use of sewage sludge, further studies including systematic monitoring are recommended. Annual metal concentrations and predicted variations of those elements in the sludge should be monitored.
  相似文献   
5.
论文选取广东省北江流域18站1965-2007年月降水数据,应用REOF方法将月降水量场划分为4个子区域,利用Mann-Kendall方法进行趋势检验,并采用滑动t检验方法进行变点分析,结果表明:流域东南部年降水量呈减少趋势,西北部呈增加趋势,年降水量增加变点出现在1992、1993年。选取REOF各分区最大特征向量载荷的站作为基准站,采用Morlet小波、交叉小波变换和小波相干分析其周期特征及其与Niño 3区SST相关关系,结果表明:4站月降水量周期变化均与Niño 3区SST相关显著;时滞相关分析表明,南雄、佛冈、连南三站月降水量变化与Niño 3区SST相关性在滞后3、4个月时最强,而三水站在同期相关性最强,这种差别可能与三水附近地区近几十年来受到的人类活动影响较强有关。  相似文献   
6.
As part of the first environmental assessment within Montevideo Harbour, in summer and winter of 1998, sediments samples were collected at eight locations to determine the spatial distribution of anthropogenic pollutants. Muddy sediments with high organic matter content dominate the study area. Heavy metal levels indicated that sediments were highly polluted with Zn (overall mean: 312+/-102 microg g(-1) dry sediment), Pb (85+/-31), Cu (89+/-25), Cr (162+/-62), and Hg (0.63+/-0.3) and moderately with Ni (30+/-2) and Ag (1.2+/-0.4). Depending on location and season, aliphatic hydrocarbons reached from 21 to 120 microg g(-1), while the unresolved complex mixture represented up to 76% of the total aliphatic fraction. Total PAH concentrations ranged from 1.56 to 90.44 microg g(-1); except at one location, petroleum derivatives were identified as main local source. The results pointed out that almost all the harbour area presented some substances that can cause adverse biological effects, especially in the inner region where all metals are above PEL levels. Principal components analysis confirmed that the inner harbour region is most severely affected by the pollutants and it was possible to differentiate three regions according to their environmental quality.  相似文献   
7.
Seasonal differences in the concentration and biochemical composition of seston have been assessed for the first time in the Humboldt Current System off northern Chile (21°S). The study comprised four seasonal surveys in the Bay of Chipana, including the summer and winter of 2006 and 2007, when El Niño 2006 and La Niña 2007 developed. Protein, lipid, carbohydrate and biogenic silica contents were measured in samples collected at four selected depths. The highest protein, lipid and carbohydrate concentrations were found at the fluorescence maximum (between 10 and 15 m depth), whereas the highest biogenic silica concentration was found 1 m above the seabed. When El Niño started developing, every variable showed low values throughout the water column; however, the lowest values were found when La Niña conditions dominated, together with low oxygen concentrations. Samples collected within the oxygen minimum zone (65 m depth) showed the lowest values for the water column and the lowest seasonal variations. After the evident decline coincident with El Niño 2006, the abundance and biochemical quality (high protein and lipid contents) of seston recovered earlier in the surface layer (upper 15 m) than at other depths.  相似文献   
8.
过去300a长江中下游异常丰梅事件变化与洪涝灾害   总被引:1,自引:0,他引:1  
2016年6—7月,长江流域发生重大洪涝灾害,给社会生产和人民生活带来严重损失。而该时段内梅雨因其强降水过程频繁、持续时间长、雨量集中等特点成为主要致灾因子。论文利用历史文献和观测资料,构建了1736年以来异常丰梅事件年表,分析了其长期变化特征及与El Ni?o事件的统计关系,并诊断了El Ni?o造成异常丰梅事件的大气环流背景。结果表明:1736—2016年间共发生44次异常丰梅事件(含21次特大梅雨事件),其中1900年代、1910年代、1990年代是异常丰梅事件最为频繁的3个时段;与2016年梅雨特征相近的特大梅雨事件有21次。过去300 a间,异常丰梅事件与El Ni?o存在较好的对应关系,44次异常丰梅事件中37次发生在El Ni?o的当年或次年;在21次特大梅雨事件中16次伴随El Ni?o出现。伴随El Ni?o事件而发生的异常丰梅事件环流特点是中高纬经向环流偏强,我国境内水汽输送通道偏西、偏北,大量水汽滞留在长江流域,并与南下的冷空气交汇,从而形成持续性降水;而在El Ni?o次年,低纬存在较强且稳定的副热带高压,水汽输送路径偏北,长江中下游水汽输送通量显著增强,更容易导致异常丰梅事件的发生。  相似文献   
9.
Chirostoma charari and C. compressum, and they are presumed extinct. Twelve (63%) of the remaining species had declines in distribution. Sixteen (80%) of the 20 localities sampled had lost species. The greatest declines occurred in Lago de Cuitzeo proper and in the lower portion of the Río Grande de Morelia watershed. Species losses from the lake were attributable to drying and hypereutrophication of the lake because of substantial reductions in the amount and quality of tributary inputs, whereas losses from the Río Grande de Morelia watershed were the result of pollution from agricultural, municipal, and industrial sources, especially in the region around the city of Morelia. Three localities in the upper portion of the Río Grande de Morelia watershed—Cointzio reservoir, La Mintzita spring, and Insurgente Morelos stream—contained most of the remaining fish species diversity in the basin and deserve additional protection. Fish faunal changes indicated major declines in the health of aquatic ecosystems in the Morelia–Cuitzeo basin.  相似文献   
10.
Abstract: The lack of concrete instances in which conservation and development have been successfully merged has strengthened arguments for strict exclusionist conservation policies. Research has focused more on social cooperation and conflict of different management regimes and less on how these factors actually affect the natural environments they seek to conserve. Consequently, it is still unknown which strategies yield better conservation outcomes? We conducted a meta‐analysis of 116 published case studies on common resource management regimes from Africa, south and central America, and southern and Southeast Asia. Using ranked sociodemographic, political, and ecological data, we analyzed the effect of land tenure, population size, social heterogeneity, as well as internally devised resource‐management rules and regulations (institutions) on conservation outcome. Although land tenure, population size, and social heterogeneity did not significantly affect conservation outcome, institutions were positively associated with better conservation outcomes. There was also a significant interaction effect between population size and institutions, which implies complex relationships between population size and conservation outcome. Our results suggest that communities managing a common resource can play a significant role in conservation and that institutions lead to management regimes with lower environmental impacts.  相似文献   
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