The Cost of Co-viability in the Australian Northern Prawn Fishery

Fisheries management must address multiple, often conflicting objectives in a highly uncertain context. In particular, while the bio-economic performance of trawl fisheries is subject to high levels of biological and economic uncertainty, the impact of trawling on broader biodiversity is also a major concern for their management. The purpose of this study is to propose an analytical framework to formally assess the trade-offs associated with balancing biological, economic and non-target species conservation objectives. We use the Australian Northern Prawn Fishery (NPF), which is one of the most valuable federally managed commercial fisheries in Australia, as a case study. We develop a stochastic co-viability assessment of the fishery under multiple management objectives. Results show that, due to the variability in the interactions between the fishery and the ecosystem, current management strategies are characterized by biological and economic risks. Results highlight the trade-offs between respecting biological, economic and non-target species conservation constraints at each point in time with a high probability and maximizing the net present value of the fishery.     

Surface ozone comparison conducted in two rural areas in central-southern Spain

Purpose  

The purpose of this work is to contribute to the understanding of the photochemical air pollution analysing the levels and temporal variations of surface ozone in two rural areas situated in central-southern Spain.     

Removal of fenhexamid and pyrimethanil from aqueous solutions by clays and organoclays

The ability of a sodium montmorillonite (CLONa) and two commercial available organoclays having interlayer organic cations possessing different functional groups (CLO20A and CLO30B) was investigated for adsorbing two pesticides namely fenexamid (FEX) and pyrimethanyl (PMT). The two organoclays displayed a higher affinity with the pesticides than the unmodified clay, but the improvement in adsorption capacity varied according to the characteristics of the pesticide and the interlayer organic cation. FEX was adsorbed to a greater extent than PMT by both organoclays, which may be due to the higher hydrophobicity of FEX thereby indicating considerable hydrophobic interaction between the adsorbent/adsorbate systems. Our findings may find application in the removal of water-soluble pesticides from aquifers.     

Uptake,translocation, and control of trumpet flower (Tecoma stans) with aminocyclopyrachlor

To gain a better understanding of the physiology of the herbicide aminocyclopyrachlor in young plants of trumpet flower, the uptake and translocation were evaluated after the application of herbicide. This was determined by treating individual leaves with formulated herbicides plus ¹⁴C-aminocyclopyrachlor after the application of the formulated herbicide. This experiment used a randomized experimental design with three replications. In addition, field studies were conducted to assess the effectiveness of foliar applications of aminocyclopyrachlor in association with metsulfuton-methyl. The plant absorbed 20% of the herbicide applied. The translocation percentage did not surpass 5% of the total amount applied. Only 1% of the herbicide applied was translocated to the roots. Rate of 40 + 13 g a.i. 100 L^?1 of aminocyclopyrachlor+metsulfuron-methyl was effective to control T. stans.     

Municipal solid waste shear strength parameters defined through laboratorial and in situ tests

This paper presents the parameters of municipal solid waste shear strength determined in the laboratory (triaxial tests) and by in situ tests: standard penetration tests (SPT) and cone penetration tests (CPT). The results analyzed here are part of a study carried out on the Santo Tirso landfill (north of Portugal) between 2001 and 2007. The influence of the strain levels, waste composition, and waste age on the shear strength parameters is presented, as well as an attempt to establish some correlations between the SPT and CPT tests and to estimate municipal solid waste (MSW) friction angles from the SPT tests. The results indicate that the aging of the waste, which is characterized by a decrease in fibrous and organic materials and an increase in inert materials and fine fraction, leads to an increase in frictional resistance and to a decrease in cohesion. The results of the SPT and CPT tests indicate higher penetration resistance in older and deeper waste. Estimating the frictional resistance from the SPT test seems to obey an empirical relationship expressed by a power function, which depends on the strain level.

Implications: Comparison of shear strength parameters of municipal solid waste (MSW) determined through laboratory (triaxial tests) and in situ tests (SPT and CPT) showed that the greater amount of fibrous and granular elements leads to an increase in “cohesion” and in friction angle values, respectively. Waste aging results in an increase in frictional resistance and in a decrease in “cohesive” resistance. This is consistent with the composition changes with aging: increase of the relative quantity of inert materials and fine fraction, and decrease in particle size, in organic matter content, and in fabrics and plastics.     

Future Nutrient Load Scenarios for the Baltic Sea Due to Climate and Lifestyle Changes

Dynamic model simulations of the future climate and projections of future lifestyles within the Baltic Sea Drainage Basin (BSDB) were considered in this study to estimate potential trends in future nutrient loads to the Baltic Sea. Total nitrogen and total phosphorus loads were estimated using a simple proxy based only on human population (to account for nutrient sources) and stream discharges (to account for nutrient transport). This population-discharge proxy provided a good estimate for nutrient loads across the seven sub-basins of the BSDB considered. All climate scenarios considered here produced increased nutrient loads to the Baltic Sea over the next 100 years. There was variation between the climate scenarios such that sub-basin and regional differences were seen in future nutrient runoff depending on the climate model and scenario considered. Regardless, the results of this study indicate that changes in lifestyle brought about through shifts in consumption and population potentially overshadow the climate effects on future nutrient runoff for the entire BSDB. Regionally, however, lifestyle changes appear relatively more important in the southern regions of the BSDB while climatic changes appear more important in the northern regions with regards to future increases in nutrient loads. From a whole-ecosystem management perspective of the BSDB, this implies that implementation of improved and targeted management practices can still bring about improved conditions in the Baltic Sea in the face of a warmer and wetter future climate.     

Shoreline development and degradation of coastal fish reproduction habitats

Coastal development has severely affected habitats and biodiversity during the last century, but quantitative estimates of the impacts are usually lacking. We utilize predictive habitat modeling and mapping of human pressures to estimate the cumulative long-term effects of coastal development in relation to fish habitats. Based on aerial photographs since the 1960s, shoreline development rates were estimated in the Stockholm archipelago in the Baltic Sea. By combining shoreline development rates with spatial predictions of fish reproduction habitats, we estimated annual habitat degradation rates for three of the most common coastal fish species, northern pike (Esox lucius), Eurasian perch (Perca fluviatilis) and roach (Rutilus rutilus). The results showed that shoreline constructions were concentrated to the reproduction habitats of these species. The estimated degradation rates, where a degraded habitat was defined as having ≥3 constructions per 100 m shoreline, were on average 0.5 % of available habitats per year and about 1 % in areas close to larger population centers. Approximately 40 % of available habitats were already degraded in 2005. These results provide an example of how many small construction projects over time may have a vast impact on coastal fish populations.

Electronic supplementary material

The online version of this article (doi:10.1007/s13280-014-0522-y) contains supplementary material, which is available to authorized users.     

Function of bacterial cells and their exuded extracellular polymeric substances (EPS) in virus removal by red soils

The potential influence of autochthonous microorganisms on virus fate in soil is usually determined through extreme conditions of sterilization vs. nonsterilization; however, the relative importance of microbial cells and their exudates remains unclear. In this study, bacterial cells (cell) were harvested, and their exuded extracellular polymeric substances (EPS) were extracted from three strains of bacteria, namely, Gram-negative bacteria Pseudomonas putida and Pseudomonas aeruginosa as well as Gram-positive bacterium Bacillus subtilis. This study aimed to evaluate virus removal in solutions in the presence of cell, EPS, and their combination (cell/EPS), as well as to investigate how their presence affects virus removal efficiencies by four red soils based on batch experiments. Results showed that virus removal percentage in solutions ranged from 11 to 23 in the presence of cells only and from 12 to 15 in the presence of EPS only. The removal percentage in the combined cell/EPS treatment can be estimated by summing the results achieved by the cell and EPS treatments, separately. Meanwhile, cell presence had a negligible effect on virus removal by red soils. EPS and combined cell/EPS significantly reduced virus removal by 20 to 69 % and 16 to 50 %, respectively, which indicated that EPS served a dominant function in reducing virus removal. This study clearly demonstrated that the prediction of virus removal by red soils must consider the effect of bacteria, especially those producing large quantities of EPS, which can be responsible for the underestimation of viral load in certain studies.     

Growth and Histopathological Effects of Chronic Exposition of Marine Pejerrey Odontesthes argentinensis Larvae to Petroleum Water-Soluble Fraction (WSF)

The water-soluble fraction (WSF) of petroleum contains a mixture of polycyclic aromatic hydrocarbons, volatile hydrocarbons, phenols, and heterocyclic compounds, considered deleterious to aquatic biota. Marine “pejerrey” Odontesthes argentinensis (Teleostei: Atherinopsidae) has a great commercial importance in local fisheries and a high potential for aquaculture. The aim of this study was to evaluate the histopathological effects in “pejerrey” larvae exposed to different concentrations of petroleum WSF. The chronic toxicity test was conducted with newly hatched larvae exposed for 21 days to sublethal concentrations of WSF (2.5, 5, 10, and 20 % of WSF), plus one control. Survival and growth were significantly lower in the highest concentration. Several histopathological changes were found in the gills (e.g., hyperplasia, aneurisms, edema, and necrosis), kidney (e.g., nuclear alterations, decrease in the hematopoietic cells), and liver (e.g., hypertrophy, karyorrhexis, and karyopyknosis). An index of branchial lesion was proposed to standardize gill lesions to different pollutants.     

Chlorpyrifos acute exposure induces hyperglycemia and hyperlipidemia in rats

In this study we evaluated the hyperglycemic and hyperlipidemic effects of chlorpyrifos (CPF) after an acute exposure in rats. The mechanisms involved in hyperglycemia induced by CPF were studied. A single dose of CPF (50 mg kg⁻¹, subcutaneous, s.c.) was administered to overnight-fasted rats. Glucose and corticosterone levels, lipid status and paraoxonase (PON1) activity were determined in plasma of rats. Cardiovascular risk factors and the atherogenic index were calculated. Glycogen levels, tyrosine aminotransferase (TAT) and glucose-6-phosphatase (G6Pase) activities were determined in livers of rats. Cerebral acetylcholinesterase (AChE) activity was also determined. CPF caused an increase in glucose and glycogen levels as well as in TAT and G6Pase activities. The CPF exposure caused an increase in corticosterone levels, an inhibition of AChE activity and a reduction of PON1 activity. Regarding the lipid status, CPF induced an increase in triglycerides (TG) and low-density lipoprotein-cholesterol (LDL) levels and a decrease in high-density lipoprotein (HDL) levels associated with an increase of cardiovascular risk factors and the atherogenic index. The present study demonstrated that a single CPF administration caused hyperglycemia and hyperlipidemia in rats. The activation of the gluconeogenesis pathway, probably elicited by hypercorticosteronemia, is involved in the hyperglycemic effect of CPF in rats.