Monitoring nitrogen loading and retention in an urban stormwater detention pond

Stormwater detention ponds have become ubiquitous in urbanized areas and have been suggested as potential hotspots of N transformation within urban watersheds. As a result, there is a great deal of interest in their use as structural best management practices to reduce the excessive N export from these watersheds. We conducted continuous monitoring of the influent and effluent N loads of a stormwater detention pond located on the Princeton University campus in Princeton, New Jersey. Our monitoring was conducted during four 21-d periods representing the four seasons of the northeastern United States. Water quality samples were collected and analyzed for nitrate (NO3-) during all four monitoring periods. During two of these periods, loads of ammonium (NH4+), dissolved organic N, and particulate N (PN) were measured. Our results show that NO3- dominated the influent N load, particularly in dry weather inflows to the detention pond. However, PN, which is often neglected in stormwater quality monitoring, made up as much as 30% of the total load and an even greater fraction during storm events. The results of our monitoring suggest that seasonal variation may play an important role in N retention within the detention pond. Although retention of NO3-, the most dominant fraction of N in the influent stormwater, was observed during the summer sampling period, no significant NO3- retention was observed during the spring or the two cold-weather sampling periods.     

Evaluating the Impacts of Mangrove Rehabilitation in Cogtong Bay,Philippines

Marine Protected Areas (MPAs) have been hailed worldwide as vehicles toward sustainable development (SD) in coastal zones. The prominent model by which MPAs operate is through a comanagement approach, a shift from traditional top-down management. This paradigm shift must be reviewed continuously to evaluate its social and ecological impacts, thereby allowing adaptive management. We evaluated the perceived impacts of the Cogtong Bay Mangrove Rehabilitation Project (CBMRP; Philippines) by using 12 perception indicators categorized into 3 comanagement impact criteria (equity, efficiency, and sustainability). We also collected 16 contextual attributes of each respondent to determine the correlates of perceived impacts. Our results showed that there were significant improvements in all indicators under the efficiency criterion but mixed impacts in the equity and sustainability criteria. Access to resource and household income (equity) and fisheries abundance (sustainability) were perceived to have decreased during the last 15 years and were not expected to improve in the future. Stepwise multiple regression analysis showed that the asymmetries of the perceived impacts of the CBMRP were principally caused by disparities in perceptions by gender and by location (Candijay and Mabini). This highlighted the importance of cross-scale institutional linkages between Cogtong Bay municipalities to systematically address baywide management issues. Our results further demonstrated the necessity of integrating gender issues into the evaluation of MPA impacts to ensure a robust evaluation. Finally, we recommend that a rigorous evaluation of MPAs using a common set of impact indicators should be encouraged to allow comparison of studies both spatially and temporally.     

The Moral Status of Fish. The Importance and Limitations of a Fundamental Discussion for Practical Ethical Questions in Fish Farming

As the world population is growing and government directives tell us to consume more fatty acids, the demand for fish is increasing. Due to declines in wild fish populations, we have come to rely more and more on aquaculture. Despite rapid expansion of aquaculture, this sector is still in a relatively early developmental stage. This means that this sector can still be steered in a favorable direction, which requires discussion about sustainability. If we want to avoid similar problems to the ones we have experienced with livestock farming, we need to generate knowledge of the biology, profitability, environmental aspects, consumer awareness, and product appreciation of particular fish species. However, the discussion about a sustainable aquaculture also raises the question how we should treat fish. This moral question is regularly addressed as a problem of applied ethics with a focus on tailoring ethical principles to practical questions. In this article we do not deny the importance of the practical accounts, but we start from the fundamental question whether and why fish matter in our moral deliberations, i.e., from the discussion on moral status. We elaborate the distinction between moral considerability and moral significance in order to show both the importance and the limitations of the discussion about moral status for practical problems in aquaculture. We illustrate these points with a case-study about the farming of a specific fish species, the African catfish.     

Fish Welfare in Aquaculture: Explicating the Chain of Interactions Between Science and Ethics

Aquaculture is the fastest growing animal-production sector in the world. This leads to the question how we should guarantee fish welfare. Implementing welfare standards presupposes that we know how to weigh, define, and measure welfare. While at first glance these seem empirical questions, they cannot be answered without ethical reflection. Normative assumptions are made when weighing, defining, and measuring welfare. Moreover, the focus on welfare presupposes that welfare is a morally important concept. This in turn presupposes that we can define the capacities of fish, which is an empirical undertaking that informs and is informed by ethical theories about the moral status of animals. In this article we want to illustrate the need for a constant interaction between empirical scientific research and ethics, in which both fields of research make their own contribution. This is not a novel claim. However, the case of fish sheds new light on this claim, because regarding fish there is still much empirical uncertainty and there is a plurality of moral views on all levels. Therefore, we do not only want to show the necessity of this interaction, but also the added value of a cooperation between ethicists and empirical scientists, such as biologists, physiologists, and ethologists. We demonstrate this by considering the different steps in the process of reflection about and implementation of fish welfare.