Stream friendly coffee: evaluating the impact of coffee farming on high-elevation streams of the Tarrazú coffee region of Costa Rica

Coffee farming is an important practice in the tropics, but studies addressing its effect on streams, especially at high elevations in high productivity regions, are limited. We evaluated streams draining the high-elevation coffee farming region of Tarrazú, Costa Rica, in terms of water quality and benthic macroinvertebrates over the course of a year. We compared our observations to regulatory benchmarks to determine overall condition, and compared our sites in terms of riparian vegetation (i.e., canopy cover, and riparian width) to determine the role of this management practice. Overall, we found that most streams fell within recommended water quality criteria and supported high proportion of pollution-sensitive taxa. Nevertheless, we found high levels of conductivity during the drier period of the year, which may signal agrochemical pollution. Also during the drier period, we found significantly higher diversity, % scrapers, and % predators, which suggests a boost in basal food sources associated to the observed high conductivity levels. We found that riparian buffer widths were not associated to improvements in water quality indicators or bio-integrity parameters on our sites. However, canopy cover was positively correlated to % shredders and family diversity, and negatively correlated to certain tolerant taxa. Our findings help to better characterize a system that is of great economic importance in the tropics, but that remains relatively under studied. It also helps inform management practices to enhance the potential of coffee agroforestry systems in promoting tropical biodiversity conservation within aquatic ecosystems.

     

A review of the enforcement regime for vessel‐source oil pollution control

Abstract

The purpose of this article is to identify the currently applicable international law intended to regulate vessel‐source pollution. Part I delineates the elements relevant for this study. Part II discusses the development of a sequence of incremental conventions. Part III examines the significance and weaknesses of the 1973 MARPOL Convention with its 1978 Protocol and of the 1982 UN. Convention on the Law of the Sea. Part IV explores alternative and/or supplementary legal approaches for handling the vessel‐source oil pollution threat.     

Reconstruction of source water using the δ18O of tree ring phenylglucosazone: A potential tool in paleoclimate studies

The oxygen isotope ratios of tree ring cellulose have a great potential as proxy for the oxygen isotope ratios of source water, which is related to climate. However, source water isotopic signatures can be masked by plant physiological and biochemical processes during cellulose synthesis. To minimize biochemical effects in the recording of source water, we modified the cellulose molecule to phenylglucosazone, which only has oxygen attached to carbon 3–6 (O_C3–6) of the cellulose glucose moieties, thus eliminating the oxygen attached to carbon 2 of the cellulose glucose moieties (O_C-2). Here we developed a method to use small amounts of inter and intra-annual tree ring cellulose for phenylglucosazone synthesis. Using this new method we tested if the oxygen isotope ratios of source water reconstructed from tree ring phenylglucosazone (δ¹⁸O_sw^PG) and the observed source water (δ¹⁸O_sw^obs) would have a better agreement than those reconstructed from the tree ring cellulose molecule. Annual tree ring samples were obtained from Pinus sylvestris (1997–2003) (Finland) and Picea abies (1971–1992) (Switzerland) and intra-annual tree ring samples were obtained from Pinus radiata (October 2004–March 2006) (New Zealand), each near a meteorological station where precipitation and relative humidity (RH) were measured periodically. The δ¹⁸O of tree ring cellulose and tree ring phenylglucosazone for each of the three species were then used to back calculate the δ¹⁸O of source water according to a previous published empirical equation. As expected, the δ¹⁸O of tree ring phenylglucosazone was superior than cellulose in the reconstruction of source water available to the plant. Deviation between δ¹⁸O_sw^PG and δ¹⁸O_sw^obs was in part correlated with variation in atmospheric relative humidity (RH) which was not observed for the cellulose molecule. We conclude that this new method can be applicable to inter and intra-annual tree ring studies and that the use of the tree ring phenylglucosazone will significantly improve the quality of paleoclimate studies.     

Health risk assessment of ‘tiger prawn seed’ collectors exposed to heavy metal pollution in the conserved mangrove forest of Indian Sundarbans: A socio-environmental perspective

Heavy metals contamination from anthropogenic sources in waterways of conserved mangrove ecosystem (Indian Sundarbans) poses serious health hazard to the economically marginalized ‘tiger prawn seed’ (TPS) collectors. Principal component analysis identifies Pb, Ni and Cd as anthropogenic pollutant in Indian Sundarbans. It is observed that Cu, Fe and Zn concentration increases in monsoon, whereas concentration of Cd and Pb decreases in comparison to pre-monsoon levels at all seven fishing villages. Economic status has been assessed using Wealth Rank Tool, which indicates 16–71% of population is in acute economic stress conditions and 5–70% of populations engaged in unsustainable TPS collection for their livelihood. Focus group discussion shows that collectors are exposed (exposure time (ET)) to contaminated water for 3–7 h/d, and lifetime exposure (exposure duration (ED)) varies from 5 to 20 yr. Using site-specific ET and ED results, cumulative hazard quotient (HQ) dermal is estimated to be higher in female than in male. HQ varies from medium (≥1 to <4) to high (>4) due to Cd pollution (0.1–0.26 mg L^-1). The study suggests that promoting alternative sustainable livelihood through group-based organizations (poultry, organic farming, entrepreneurship and transport) could be an effective solution to this problem.     

Characterisation of CpG methylation in the upstream control region of mouse Nat2: Evidence for a gene–environment interaction in a polymorphic gene implicated in folate metabolism

Human arylamine N-acetyltransferase 1 (NAT1), a polymorphic xenobiotic metabolising enzyme, has been investigated in relation to susceptibility and prognosis in certain types of cancer. Both human NAT1 and its murine equivalent NAT2 have previously been shown to play roles in the catabolism of folate, which is required for the synthesis of S-adenosylmethionine, the methyl donor for cellular methylation reactions. We have tested whether the expression of mouse Nat2 is subject to epigenetic regulation, specifically CpG methylation in the promoter region, by determining levels of 5-methylcytosine by bisulphite sequencing and methylation-specific PCR. Under normal conditions, methylation levels of the Nat2 promoter were low, and varied in different tissues. However, CpG methylation was significantly increased by dietary folate supplementation, and increased methylation corresponded to decreased use of the core promoter. Functional deletion of the Nat2 gene gave rise to a significant increase in Nat2 methylation, extending our previous observations that folate catabolism is decreased in Nat2 null mice. Mouse NAT2 is likely to influence epigenetic gene control, particularly of its own locus, and this is consistent with recent evidence associating aberrant mouse Nat2/human NAT1 gene expression with certain developmental malformations and cancers.     

A simple tool for the assessment of water quality in polluted lagoon systems: A case study for Küçükçekmece Lagoon,Turkey

Lagoon systems have particular ecological, morphological and hydrodynamic characteristics and act like transitional zones between inland and open waters. The aim of this study is to develop a Lagoon Water Quality Index (L-WQI) for environmental control of polluted lagoon systems by focusing on primary problems such as increasing stress on aquatic biota, eutrophication and organic pollution. The indicators used in L-WQI are dissolved oxygen saturation, total nitrogen to total phosphorus ratio, nitrate, orthophosphate, chlorophyll-a, chemical oxygen demand, pH, turbidity and electrical conductivity. L-WQI establishes a new normalization function for each variable and uses a modified version of the weighted aggregation method. L-WQI has been adapted to Küçükçekmece Lagoon, a highly polluted watershed located in western Istanbul. The results correlated with the observed water quality trends in this lagoon and highlighted the impact of pollution in its tributaries.     

A novel social life cycle assessment method for determining workers’ human development: a case study of the sugarcane biorefineries in Brazil

The International Journal of Life Cycle Assessment - The social life cycle assessment (S-LCA) methodology needs to advance in its methodological development, mainly regarding the impact assessment...     

A public health risk assessment for yellow fever vaccination: a model exemplified by an outbreak in the state of S?o Paulo,Brazil

We propose a method to analyse the 2009 outbreak in the region of Botucatu in thestate of São Paulo (SP), Brazil, when 28 yellow fever (YF) cases were confirmed,including 11 deaths. At the time of the outbreak, the Secretary of Health of theState of São Paulo vaccinated one million people, causing the death of fiveindividuals, an unprecedented number of YF vaccine-induced fatalities. We apply amathematical model described previously to optimise the proportion of people whoshould be vaccinated to minimise the total number of deaths. The model was used tocalculate the optimum proportion that should be vaccinated in the remaining,vaccine-free regions of SP, considering the risk of vaccine-induced fatalities andthe risk of YF outbreaks in these regions.