Evaluating the vulnerability of surface waters to antibiotic contamination from varying wastewater treatment plant discharges

Effluents from three wastewater treatment plants with varying wastewater treatment technologies and design were analyzed for six antibiotics and caffeine on three sampling occasions. Sulfamethoxazole, trimethoprim, ciprofloxacin, tetracycline, and clindamycin were detected in the effluents at concentrations ranging from 0.090 to 6.0 microg/L. Caffeine was detected in all effluents at concentrations ranging from 0.19 to 9.9 microg/L. These findings indicate that several conventional wastewater management practices are not effective in the complete removal of antibiotics, and their discharges have a large potential to affect the aquatic environment. To evaluate the persistence of antibiotics coming from the wastewater discharges on the surrounding surface waters, samples were collected from the receiving streams at 10-, 20- and 100-m intervals. Ciprofloxacin, sulfamethoxazole, and clindamycin (0.043 to 0.076 microg/L) were found as far as 100 m from the discharge point, which indicates the persistence of these drugs in surface waters.     

Range-wide Yangtze freshwater dolphin expedition: The last chance to see Baiji?

BACKGROUND, AIM AND SCOPE: There are two species of fresh water cetaceans surviving in the Yangtze River system in China: Baiji (Lipotes vexillifer) and Yangtze finless porpoise (Neophocaena phocaenoides asiaeorientalis). As a result of the expansion of human activities on the river, their distribution ranges appear to be decreasing and in the case of the Baiji, are even being restricted to several sections. The Baiji is the world's most critically endangered cetacean species with a population estimated at only a few tens of individuals. The Yangtze finless porpoise is the world's only freshwater-adapted population of the species, and it has been estimated that only around 1,000 individuals remain in the river system. In order to prevent the extinction of Baiji and a sharp decline in the abundance of the porpoise, in situ conservation (i.e. in the river) and two ex situ conservation (i.e. in semi-natural reserves and in captivity) strategies were proposed and have been implemented since the early 1990s. In view of both the severely endangered status of the animals and the severely degraded conditions of their habitats, the feasibility and actual status of these two strategies are raised for discussion. MAIN FEATURES: The threats faced by the cetaceans are mainly from the unfettered exploitation of the river's resources. In the past 20 years, five nature reserves have been established along the river. Imposing maximum prohibition of harmful and illegal fishing methods in the reserves might prolong the process of extinction of these cetaceans in the wild, but so far, the administrative measures taken in the reserves have not yet kept the abundance from sharply declining. As human use of the river and its resources is expected to intensify for many decades into the future, the ability of the river to continue to support these species is certainly undecided. Therefore, rescuing animals from the river and establishing viable breeding populations in seminatural reserves, in which the environment is similar to the main stream of the river, and in captivity, has to be considered urgently as the short-term goal of ex situ strategies. Since the abundance of porpoises is higher than that of the Baiji, we have first established breeding populations of them in the semi-natural reserves and in captivity. But, considering the extremely low density of Baiji in the river, an immediate range-wide Yangtze Baiji survey is an urgent need for locating and capturing sufficient Baiji for successfully establishing a breeding population of them in semi-natural reserves. RESULTS: Two semi-natural reserves (in Shishou, Hubei Province, and Tongling, Anhui Province) have been set up along the river in order to establish breeding populations of the Baiji and the porpoises. So far, several small groups of porpoises that were caught in the main stream of the river have successively been introduced into the semi-natural reserves. Under careful management, these animals in both of the semi-natural reserves not only survive, but can also reproduce naturally and successfully. At least one or three calves were born in each reserve each year. Additionally, a breeding group of porpoises is being established at the Baiji Dolphinarium at the Institute of Hydrobiology, Chinese Academy of Sciences, Wuhan. There are presently four adults and one calf living in the Dolphinarium. The calf, born in July, 2005, is the first captive bred Yangtze Finless Porpoise in the world. In preparation for the range-wide Yangtze cetacean survey, a 9-day pilot expedition on the river near Wuhan was conducted in March, 2006, in order to develop methods for locating the Baiji. No Baiji were expected to be seen in such a short period but about 40 porpoise sightings were observed. Results of the pilot survey indicated that traditional visual and acoustical survey methods for cetaceans should be adapted to find the elusive Baiji in the river. Currently, the range-wide Yangtze cetacean survey is in preparation. The survey will cover over 1,700 km of the Yangtze River from Yichang to Shanghai, and is expected to provide detailed information on Baiji and porpoise numbers and distribution patterns in the river. DISCUSSION: Although the short-term goal of ex situ conservation is to rescue cetaceans from the river and to establish viable breeding populations in semi-natural reserves and in captivity, the long-term goal of releasing the animals back into the river when the threats have decreased and the natural environment has been improved, should not be neglected. Moreover, the in situ conservation efforts in the natural reserves, and even in the entire Yangtze River system, including the lakes, should not be ignored or abandoned at any time. The activities contributing to the conservation of the Baiji and the porpoise in the wild have the incidental effect of benefiting the entire Yangtze ecosystem and other rare threatened species. The dynamics of the groups of porpoises in semi-natural reserves should be monitored continually, in order to guide the establishment of breeding groups of Baiji in these semi-natural reserves in the near future. CONCLUSIONS: Under the existing severely degraded conditions of the Yangtze system, the sharply fall populations of Baiji and porpoises will not be suspended in the foreseeable future. Therefore, ex situ conservation should be emphasized, and the severely threatened Baiji in the river should be removed and translocated to semi-natural reserves for establishing viable breeding populations. The successful program of capturing, translocating and maintaining finless porpoises in the Shishou semi-natural reserve has demonstrated its adequacy as an ex situ environment for cetaceans. Following the successful pilot survey in the river, the immediate range-wide Yangtze cetacean survey is proposed and is in preparation. The range-wide survey is expected to ensure that any remaining Baiji can be found reliably and captured successfully after the survey. RECOMMENDATIONS AND PERSPECTIVES: During the range-wide survey, not only the Baiji but also the porpoise as well as their habitats should be investigated based on visual and acoustical methods that adapted to the river and the animals. Meanwhile, the current risk levels to the Baiji and porpoises should be evaluated at each area where Baiji or porpoises can be reliably sighted. Any capture efforts should be targeted on the most threatened areas, or where there is maximum risk of injury or death. The immediate track of the Baiji should be carried out once a Baiji is sighted during the range-wide survey in order to obtain the movement route of the animals, which is crucial information for the successful capture operation. Additionally, the need to establish new semi-natural reserves for the porpoises should be placed on the agenda of local and central governments in the near future.     

CONNECTING GROUND WATER INFLUXES WITH FISH SPECIES DIVERSITY IN AN URBANIZED WATERSHED1

ABSTRACT: Valley Creek watershed is a small stream system that feeds the Schuylkill River near Philadelphia, Pennsylvania. The watershed is highly urbanized, including over 17 percent impervious surface cover (ISC) by area. Imperviousness in a watershed has been linked to fish community structure and integrity. Generally, above 10 to 12 percent ISC there is marked decline in fish assemblages with fish being absent above 25 percent ISC. This study quantifies the importance of ground water in maintaining fish species diversity in subbasins with over 30 percent ISC. Valley Creek contains an atypical fish assemblage in that the majority of the fish are warm‐water species, and the stream supports naturally reproducing brown trout, which were introduced and stocked from the early 1900s to 1985. Fish communities were quantified at 13 stations throughout the watershed, and Simpson's species diversity index was calculated. One hundred and nine springs were located, and their flow rates measured. A cross covariance analysis between Simpson's species diversity index and spring flow rates upstream of fish stations was performed to quantify the spatial correlation between these two variables. The correlation was found to be highest at lag distances up to about 400 m and drop off significantly beyond lag distances of about 800 m.     

A life-cycle comparison of several auxiliary blowing agents used for the manufacture of rigid polyurethane foam

In a commitment to zero ozone depletion, the United Nations and the U.S. Environmental Protection Agency (EPA) have called for the phase-out of the manufacture and import of hydrochlorofluorocarbons (HCFCs), used as auxiliary blowing agents (ABAs) in the manufacture of polyurethane foams. As a result, more environmentally benign alternative ABAs are being sought by the foam-blowing industry. This study examined the life cycle of HCFC-22, hydrofluorocarbon-134a (HFC-134a), and cyclopentane, which are currently used or considered as potential alternative ABAs in the manufacture of rigid polyurethane foams that serve as insulation in a model North American refrigerator. The raw material extraction/refining, manufacturing, use, and disposal stages of the life cycle of each ABA were considered, and their resulting relative impacts on ozone depletion and global warming were compared. The manufacturing, use, and disposal stages were determined to affect ozone depletion and global warming to the largest extent, emphasizing the need for a greater focus on pollution prevention opportunities in these stages. The HFC-134a life cycle yields no impact on ozone depletion and a significantly decreased global warming impact compared with its predecessor, HCFC-22, and a tradeoff of slightly higher global warming impact and fewer added safety concerns compared with its more flammable counterpart, cyclopentane.     

Day length,latitude and behavioural (in)flexibility in baboons<Emphasis Type="Italic"> (Papio cynocephalus ursinus</Emphasis>)

Annual cycles in day length are an important consideration in any analysis of seasonal behaviour patterns, since they determine the period within which obligate diurnal or nocturnal animals must conduct all of their essential activities. As a consequence, seasonal variation in day length may represent an ecological constraint on behaviour, since short winter days restrict the length of the time available for foraging in diurnal species (with long summer days, and thus short nights, a potential constraint for nocturnal species). This paper examines monthly variation in activity patterns over a 4-year study of chacma baboons (Papio cynocephalus ursinus) at De Hoop Nature Reserve, South Africa. Time spent feeding, moving, grooming and resting are all significant positive functions of day length, even before chance events such as disease epidemics and climatically mediated home range shifts have been accounted for. These results provide strong support for the idea that day length acts as an ecological constraint by limiting the number of daylight hours and thus restricting the active period at certain times of year. Day length variation also has important implications across populations. Interpopulation variation in resting time, and non-foraging activity in general, is a positive function of latitude, with long summer days at temperate latitudes apparently producing an excess of time that cannot profitably be devoted to additional foraging or social activity. However, it is the short winter days that are probably of greatest importance, since diurnal animals must still fulfil their foraging requirements despite the restricted number of daylight hours and elevated thermoregulatory requirements at this time of year. Ultimately this serves to restrict the maximum ecologically tolerable group sizes of baboon populations with increasing distance from the equator. Seasonal variation in day length is thus an important ecological constraint on animal behaviour that has important implications both within and between populations, and future studies at non-equatorial latitudes must clearly be mindful of its importance.     

A technology for the treatment of olive-mill waste water in a continuously fed plant

A bench-scale pilot plant has been developed for the treatment of olive-mill water. The plant is fed in a continuous mode and implements a primary treatment (sand filtering and irradiation with UV-rays) and a secondary treatment (anoxic and aerobic biological treatment). Satisfactory results were obtained and the treated green water falls under the limits of the Italian legislation. Veratric and ferulic acid biodegradation were studied under anoxic conditions in order to verify the requirements for optimal biodegradation. Electronic Publication     

Violence and complex humanitarian emergencies: implications for livelihoods models

This paper explores the nature of the violence that characterises complex humanitarian emergencies and the related implications for modelling livelihoods systems. While noting the importance of livelihoods approaches in complex humanitarian emergencies, it deliberates the limitations of sustainable livelihoods frameworks when applied in environments marked by protracted instability. Adaptations to the model are discussed, with a particular focus on the relationships among violence, assets and liabilities within livelihoods systems. Political economy of violence theories intimate that the assets on which livelihoods systems are constructed in peaceful times may instead become life-and livelihood-threatening liabilities in periods of conflict. Adaptations to livelihood systems in violent settings require that analysts consider violence from policy, institutional and process perspectives. It is suggested that vulnerability should be re-conceptualised as endogenous to livelihoods systems in violent settings. Building on the work of others, a livelihoods model adapted for complex humanitarian emergencies is presented.     

The net ecosystem carbon exchange of human-modified environments in the Australian Capital Region

As part of a larger study to quantify and map ecosystem services in southeast Australia, we estimated carbon stored in biomass and soils and the net ecosystem carbon exchange between the land surface and the atmosphere in the Australian Capital Region (ACR). Our aim was to understand and quantify how different human-modified landscapes provide an essential ecosystem service: the exchange and storage of carbon in the landscape. Using a remote sensing based modelling methodology, we obtained values of Net Primary Productivity (NPP), total carbon in soil and biomass and carbon turnover from meteorological and terrain inputs and vegetation attributes. We obtained a set of maps of NPP, total carbon (C) storage and C-turnover for the ACR. We superimposed a land use/cover map to assign the uptake, storage and release of carbon to different land use/cover types. Our results support the hypothesis that human-intensive land uses significantly affect the ability of terrestrial ecosystems to provide an important ecosystem service in the form of carbon storage.