Boosting freshwater fish conservation with high-resolution distribution mapping across a large territory

The lack of high-resolution distribution maps for freshwater species across large extents fundamentally challenges biodiversity conservation worldwide. We devised a simple framework to delineate the distributions of freshwater fishes in a high-resolution drainage map based on stacked species distribution models and expert information. We applied this framework to the entire Chinese freshwater fish fauna (>1600 species) to examine high-resolution biodiversity patterns and reveal potential conflicts between freshwater biodiversity and anthropogenic disturbances. The correlations between spatial patterns of biodiversity facets (species richness, endemicity, and phylogenetic diversity) were all significant (r = 0.43–0.98, p < 0.001). Areas with high values of different biodiversity facets overlapped with anthropogenic disturbances. Existing protected areas (PAs), covering 22% of China's territory, protected 25–29% of fish habitats, 16–23% of species, and 30–31% of priority conservation areas. Moreover, 6–21% of the species were completely unprotected. These results suggest the need for extending the network of PAs to ensure the conservation of China's freshwater fishes and the goods and services they provide. Specifically, middle to low reaches of large rivers and their associated lakes from northeast to southwest China hosted the most diverse species assemblages and thus should be the target of future expansions of the network of PAs. More generally, our framework, which can be used to draw high-resolution freshwater biodiversity maps combining species occurrence data and expert knowledge on species distribution, provides an efficient way to design PAs regardless of the ecosystem, taxonomic group, or region considered.     

The need for spatially explicit quantification of benefits in invasive‐species management

Worldwide, invasive species are a leading driver of environmental change across terrestrial, marine, and freshwater environments and cost billions of dollars annually in ecological damages and economic losses. Resources limit invasive‐species control, and planning processes are needed to identify cost‐effective solutions. Thus, studies are increasingly considering spatially variable natural and socioeconomic assets (e.g., species persistence, recreational fishing) when planning the allocation of actions for invasive‐species management. There is a need to improve understanding of how such assets are considered in invasive‐species management. We reviewed over 1600 studies focused on management of invasive species, including flora and fauna. Eighty‐four of these studies were included in our final analysis because they focused on the prioritization of actions for invasive species management. Forty‐five percent (n = 38) of these studies were based on spatial optimization methods, and 35% (n = 13) accounted for spatially variable assets. Across all 84 optimization studies considered, 27% (n = 23) explicitly accounted for spatially variable assets. Based on our findings, we further explored the potential costs and benefits to invasive species management when spatially variable assets are explicitly considered or not. To include spatially variable assets in decision‐making processes that guide invasive‐species management there is a need to quantify environmental responses to invasive species and to enhance understanding of potential impacts of invasive species on different natural or socioeconomic assets. We suggest these gaps could be filled by systematic reviews, quantifying invasive species impacts on native species at different periods, and broadening sources and enhancing sharing of knowledge.     

Matrix Diffusion Modeling Applied to Long‐Term Pump‐and‐Treat Data: 2. Results From Three Sites

The data mining/groundwater modeling methodology developed in McDade et al. (2013) was performed to determine if matrix diffusion is a plausible explanation for the lower‐concentration but persistent chlorinated solvent plumes in the groundwater‐bearing units at three different pump‐and‐treat systems. Capture‐zone maps were evaluated, and eight wells were identified that did not draw water from any of the historical source areas but captured water from the sides of the plume. Two groundwater models were applied to study the persistence of the plumes in the absence of contributions from the historical source zones. In the wells modeled, the observed mass discharge generally decreased by about one order of magnitude or less over 4 to 10 years of pumping, and 1.8 to 17 pore volumes were extracted. In five of the eight wells, the matrix diffusion model fit the data much better than the advection dispersion retardation model, indicating that matrix diffusion better explains the persistent plume. In the three other wells, confounding factors, such as a changing capture zone over time (caused by changes in pumping rates in adjacent extraction wells); potential interference from a high‐concentration unremediated source zone; and limited number of pore volumes removed made it difficult to confirm that matrix diffusion processes were active in these areas. Overall, the results from the five wells indicate that mass discharge rates from the pumping wells will continue to show a characteristic “long tail'' of mass removal from zones affected by active matrix diffusion processes. Future site management activities should include matrix diffusion processes in the conceptual site models for these three sites. © 2013 Wiley Periodicals, Inc.     

Urban Development and Air Quality in San Luis City, Argentina

Some factors such as the high population growth, along with insufficient housing, health and sanitary services, obsolete industrial technology and the lack of environmental management programs, give rise to contamination in Latin-American cities. Owing to the urban characteristics of San Luis, a detailed analysis of air quality was planned as part of a more comprehensive study, in order to make an environmental diagnosis of the city after the demographical and economic upgrowth over the last 15 years. It has been concluded that air pollution levels in San Luis are higher than those expected for a medium-size city. The reported high levels were attributed to important industrial activity, responsible not only for the direct of polluting gases to the atmosphere but also as the principal cause of the urban expansion. The levels of CO and SO₂ (ppm) found in the city can be considered as high. Some weeks during the sampling measure values were appreciably higher than the maximum tolerance levels established. The urban area under study was separated into five defined areas, which allowed to make comparisons in order to identify specific contamination problems. The slopes corresponding to the plot polluting substances concentration vs. wind speed were lower than the expected values. Because of the urban area characteristics, different micrometeorological effects facilitating a low air exchange can be generated, and consequently increasing the contamination levels. Thus, it is correct to conclude that the degradation processes are not occurring in a single environmental plane. Accordingly, air contamination rate in San Luis city could be considered as evidence of other upper-scale regional environmental degradation processes.     

Growth, photosynthetic and respiratory responses to sub-lethal copper concentrations in Scenedesmus incrassatulus (Chlorophyceae)

In the present paper we investigated the effects of sub-lethal concentrations of Cu²⁺ in the growth and metabolism of Scenedesmus incrassatulus. We found that the effect of Cu²⁺ on growth, photosynthetic pigments (chlorophylls and carotenoids) and metabolism do not follow the same pattern. Photosynthesis was more sensitive than respiration. The analysis of chlorophyll a fluorescence transient shows that the effect of sub-lethal Cu²⁺ concentration in vivo, causes a reduction of the active PSII reaction centers and the primary charge separation, decreasing the quantum yield of PSII, the electron transport rate and the photosynthetic O₂ evolution. The order of sensitivity found was: Growth > photosynthetic pigments content = photosynthetic O₂ evolution > photosynthetic electron transport > respiration. The uncoupled relationship between growth and metabolism is discussed.     

The association between prenatal exposure to polycyclic aromatic hydrocarbons and childhood intelligence: a systematic review of observational studies

Environmental Science and Pollution Research - Exposure to polycyclic aromatic hydrocarbons (PAHs) during pregnancy has been associated with many adverse child health. However, the evidence on such...     

Sensitivity of amounts and distribution of tropical forest carbon credits depending on baseline rules

One of the largest sources of global greenhouse gas emissions can be addressed through conservation of tropical forests by channeling funds to developing countries at a cost-savings for developed countries. However, questions remain to be resolved in negotiating a system for including reduced emissions from deforestation and forest degradation (REDD) in a post-Kyoto climate treaty. The approach to determine national baselines, or reference levels, for quantifying REDD has emerged as central to negotiations over a REDD mechanism in a post-Kyoto policy framework. The baseline approach is critical to the success of a REDD mechanism because it affects the quantity, credibility, and equity of credits generated from efforts to reduce forest carbon emissions. We compared outcomes of seven proposed baseline approaches as a function of country circumstances, using a retrospective analysis of FAO-FRA data on forest carbon emissions from deforestation. Depending upon the baseline approach used, the total credited emissions avoided ranged over two orders of magnitude for the same quantity of actual emissions reductions. There was also a wide range in the relative distribution of credits generated among the five country types we identified. Outcomes were especially variable for countries with high remaining forest and low rates of deforestation (HFLD). We suggest that the most credible approaches measure emissions avoided with respect to a business-as-usual baseline scenario linked to historic emissions data, and allow limited adjustments based on forest carbon stocks.     

Do artificial structures alter marine invertebrate genetic makeup?

Human-made structures are increasingly built in marine coastal habitats for a variety of purposes. Offshore oil and gas production platforms are among the largest examples. Yet, biological effects of these increasing density artificial substrata are under evaluated. The objective of our study is to investigate the possible role of offshore platforms in modifying the genetic composition of populations of natural rocky shores species. The serpulid Pomatoceros triqueter was used as a model, and genetic variation was assessed using a 419?bp fragment of the mtDNA COI gene in samples collected on eleven offshore gas platforms, on one coastal buoy on the sandy shore and in four sites located on natural rocky shores in the Adriatic Sea. Deep phylogenetic lineages were uncovered over all samples. Nucleotide diversity and mean number of pairwise differences among haplotypes were significantly smaller in offshore platform samples compared to rocky shores samples. No significant genetic structure was observed over all samples. We found direct evidence of lower genetic diversity on platforms confirming that, although artificial structures attract and support species typical of hard bottoms, they are not analogues of natural rocky habitats.