Comparison of GC-MS and FTIR methods for quantifying naphthenic acids in water samples

The extraction of bitumen from the oil sands in Canada releases toxic naphthenic acids into the process-affected waters. The development of an ideal analytical method for quantifying naphthenic acids (general formula C(n)H(2n+Z)O(2)) has been impeded by the complexity of these mixtures and the challenges of differentiating naphthenic acids from other naturally-occurring organic acids. The oil sands industry standard FTIR method was compared with a newly-developed GC-MS method. Naphthenic acids concentrations were measured in extracts of surface and ground waters from locations within the vicinity of and away from the oil sands deposits and in extracts of process-affected waters. In all but one case, FTIR measurements of naphthenic acids concentrations were greater than those determined by GC-MS. The detection limit of the GC-MS method was 0.01 mg L(-1) compared to 1 mg L(-1) for the FTIR method. The results indicated that the GC-MS method is more selective for naphthenic acids, and that the FTIR method overestimates their concentrations.     

Extinction of a West African Red Colobus Monkey

Abstract: We provide the first documented case of the extinction in the twentieth century of a widely recognized primate taxon. During surveys in Ghana and Côte d'Ivoire in 1993–1999, we were unable to find any surviving populations of Miss Waldron's red colobus monkey (   Procolobus badius waldroni ), a primate taxon endemic to the forests of this part of West Africa. We conclude that this monkey, which at least one authority considers worthy of species status, is probably extinct. Hunting by humans appears to be the ultimate cause of the extinction. Until our surveys began, little attention had been paid to the plight of this red colobus monkey, despite its listing as endangered by the World Conservation Union. The extinction of other large animals in the Upper Guinea rainforest region is likely to follow soon unless more attention is paid to the full range of endangered forms and more resources are devoted to their rigorous protection.     

Thinning Pine Plantations to Reestablish Oak Openings Species in Northwestern Ohio

Globally the area in forest plantations is rising by 2% annually, increasing the importance of plantations for production of human goods and services and for ecological functions such as carbon storage and biodiversity conservation. Specifically in the Great Lakes states and provinces of Midwestern North America, thousands of hectares of pine plantations were established in the early and mid-1900s to revegetate abandoned agricultural fields that had replaced mixed-species forests and oak–prairie ecosystems. Plantation establishment also was intended to bolster the timber base. Management priorities have shifted, with many resource managers currently seeking to manage existing plantations for promoting mixed-species ecosystems. The purpose of this study was to assess plant succession and the reestablishment of oak savanna and prairie species after thinning 14 plantations of Pinus resinosa and strobus in northwestern Ohio, USA. Thinning reduced tree basal area by an average of 75%. Plant communities were sampled on 0.05-ha plots one and 3 years after thinning and compared to 10 unthinned control plantations. By 3 years after thinning, thinned plots contained 2–3 times more species and 14 times more plant cover than control plots. The species composition of colonizing plants was most strongly correlated with residual pine basal area and soil variables related to drainage (e.g., sand concentration, available water capacity). Although plant composition was dominated by widespread colonizers such as Erechtites hieraciifolia, the coefficient of conservatism (indicative of species of more intact, undisturbed communities) significantly increased on thinned plots from year 1 to 3. This finding, coupled with the presence of four rare, state-listed Ohio species whose eight plot occurrences all were on thinned plots, suggests that plant composition is moving towards species typifying more high-quality savanna and prairie habitats.     

Variation of the mixing state of Saharan dust particles with atmospheric transport

Mineral dust is an important aerosol species in the Earth’s atmosphere and has a major source within North Africa, of which the Sahara forms the major part. Aerosol Time of Flight Mass Spectrometry (ATOFMS) is first used to determine the mixing state of dust particles collected from the land surface in the Saharan region, showing low abundance of species such as nitrate and sulphate internally mixed with the dust mineral matrix. These data are then compared with the ATOFMS single particle mass spectra of Saharan dust particles detected in the marine atmosphere in the vicinity of the Cape Verde islands, which are further compared with those from particles with longer atmospheric residence sampled at a coastal station at Mace Head, Ireland. Saharan dust particles collected near the Cape Verde Islands showed increased internally mixed nitrate but no sulphate, whilst Saharan dust particles collected on the coast of Ireland showed a very high degree of internally mixed secondary species including nitrate, sulphate and methanesulphonate. This uptake of secondary species will change the pH and hygroscopic properties of the aerosol dust and thus can influence the budgets of other reactive gases, as well as influencing the radiative properties of the particles and the availability of metals for dissolution.     

Selenium stable isotope investigation into selenium biogeochemical cycling in a lacustrine environment: Sweitzer Lake, Colorado

We present a comprehensive set of Se concentration and isotope ratio data collected over a 3-yr period from dissolved, sediment-hosted, and organically bound Se in a Se-contaminated lake and littoral wetland. Median isotope ratios of these various pools of Se spanned a narrow isotopic range (delta80/76Se(SRM-3149)) = 1.14-2.40 per thousand). Selenium (VI) reduction in the sediments is an important process in this system, but its isotopic impact is muted by the lack of direct contact between surface waters and reduction sites within sediments. This indicates that using Se isotope data as an indicator of microbial or abiotic Se oxyanion reduction is not effective in this or other similar systems. Isotopic data suggest that most Se(IV) in the lake originates from oxidation of organically bound Se rather than directly through Se(VI) reduction. Mobilization of Se(VI) from bedrock involves only a slight isotopic shift. Temporally constant isotopic differences observed in Se(VI) from two catchment areas suggest the potential for tracing Se(VI) from different source areas. Phytoplankton isotope ratios are close to those of the water, with a small depletion in heavy isotopes (0.56 per thousand). Fish tissues nearly match the phytoplankton, being only slightly depleted in the heavier isotopes. This suggests the potential for Se isotopes as migration indicators. Volatile, presumably methylated Se was isotopically very close to median values for phytoplankton and macrophytes, indicating a lack of isotopic fractionation during methylation.     

Experimental evidence for a dual pathway model analysis of coping with the climate crisis

Two experiments examined the psychological power of fear and group efficacy beliefs to increase environmental action intentions against the climate crisis. Extending a dual pathway model of coping with collective disadvantage, results showed evidence for emotion-focused approach coping: Environmental action intentions were increased by individuals' manipulated fear of the negative future consequences of the climate crisis (Experiments 1–2). Additionally, results showed evidence for problem-focused approach coping: Individuals' measured (Experiment 1) and manipulated group efficacy beliefs (Experiment 2) increased environmental action intentions. The results thus suggest that the dual pathway model can be successfully applied to a psychological analysis of emotion- and problem-focused approach coping with the climate crisis. We discuss the theoretical and practical implications of these results.     

Surface applied water treatment residuals affect bioavailable phosphorus losses in Florida sands

Water treatment residuals (WTR) can reduce runoff P loss and surface co-application of P-sources and WTR is a practical way of land applying the residuals. In a rainfall simulation study, we evaluated the effects of surface co-applied P-sources and an Al-WTR on runoff and leacheate bioavailable P (BAP) losses from a Florida sand. Four P-sources, namely poultry manure, Boca Raton biosolids (high water-soluble P), Pompano biosolids (moderate water-soluble P), and triple super phosphate (TSP) were surface applied at 56 and 224kgPha(-1) (by weight) to represent low and high soil P loads typical of P- and N-based amendments rates. The treatments further received surface applied WTR at 0 or 10gWTRkg(-1) soil. BAP loss masses were greater in leachate (16.4-536mg) than in runoff (0.91-46mg), but were reduced in runoff and leachate by surface applied WTR. Masses of total BAP lost in the presence of surface applied WTR were less than approximately 75% of BAP losses in the absence of WTR. Total BAP losses from each of the organic sources applied at N-based rates were not greater than P loss from TSP applied at a P-based rate. The BAP loss at the N-based rate of moderate water-soluble P-source (Pompano biosolids) was not greater than BAP losses at the P-based rates of other organic sources tested. The hazards of excess P from applying organic P-sources at N-based rates are not greater than observed at P-based rates of mineral fertilizer. Results suggest that management of the environmental P hazards associated with N-based rates of organic materials in Florida sands is possible by either applying P-sources with WTR or using a moderate water-soluble P-source.     

Distribution of Economic Benefits from Ecotourism: A Case Study of Wolong Nature Reserve for Giant Pandas in China

Ecotourism is widely promoted as a conservation tool and actively practiced in protected areas worldwide. Theoretically, support for conservation from the various types of stakeholder inside and outside protected areas is maximized if stakeholders benefit proportionally to the opportunity costs they bear. The disproportional benefit distribution among stakeholders can erode their support for or lead to the failure of ecotourism and conservation. Using Wolong Nature Reserve for Giant Pandas (China) as an example, we demonstrate two types of uneven distribution of economic benefits among four major groups of stakeholders. First, a significant inequality exists between the local rural residents and the other types of stakeholder. The rural residents are the primary bearers of the cost of conservation, but the majority of economic benefits (investment, employment, and goods) in three key ecotourism sectors (infrastructural construction, hotels/restaurants, and souvenir sales) go to other stakeholders. Second, results show that the distribution of economic benefits is unequal among the rural residents inside the reserve. Most rural households that benefit from ecotourism are located near the main road and potentially have less impact on panda habitat than households far from the road and closer to panda habitats. This distribution gap is likely to discourage conservation support from the latter households, whose activities are the main forces degrading panda habitats. We suggest that the unequal distribution of the benefits from ecotourism can be lessened by enhancing local participation, increasing the use of local goods, and encouraging relocation of rural households closer to ecotourism facilities.     

Validation of an ecosystem modelling approach as a tool for ecological effect assessments

In ecotoxicology, derivation of a "safe" environmental concentration is usually achieved by the use of extrapolation factors or by statistical extrapolation from a set of single species toxicity data. These approaches ignore ecological interactions between species in the field. An ecology-based alternative to this pragmatic approach can be ecosystem modelling, which can account for ecological interactions. However, it is largely unexplored how well the predictions of these models quantitatively agree with large-scale experimental studies. Therefore, we evaluated the capacity of a flexible ecosystem model to predict population and ecosystem-level no observed effect concentrations (NOECs) of 7 organic toxicants. These NOECs were compared with population and ecosystem-NOECs observed in 11 micro- and mesocosm studies. For each of the latter studies, the model was customized to account for the specific ecological interactions within these systems and combined with appropriate single-species toxicity data from literature. Population-NOEC predictions were accurate, or at least protective, for 60, and 85% of all considered model populations, respectively. For all 11 studies, a protective ecosystem-NOEC could be derived, being accurate in 7 cases, and conservative in 4 cases. In general, it can be stated that this type of models can serve as an ecology-based alternative to current extrapolation techniques in EEAs and water quality standard setting.