Daily Archives: November 17, 2014

Worldwide Climate-Related Deaths have Decrease; Livability has Increased due to Fossil Fuels

Let’s keep the big picture clearly in focus.

“Here are a couple of striking numbers from the data: in the decade from 2004 to 2013, worldwide climate-related deaths (including droughts, floods, extreme temperatures, wildfires, and storms) plummeted to a level 88.6 percent below that of the peak decade, 1930 to 1939.2 The year 2013, with 29,404 reported deaths, had 99.4 percent fewer climate-related deaths than the historic record year of 1932, which had 5,073,283 reported deaths for the same category.3 ” Click here for article.

And I strongly suspect that an honest assessment would find a direct correlation between improvements in the health of the inhabitants of a country or area over several previous decades and the availability of affordable energy (primarily fossil fuels). Are there negative environmental impacts that should be avoided in the future? Sure. But one must focus on the bigger picture.

Alum Sludge on Vegetative Buffer Strips Reduced Phosphorus in Surface Runoff

Habibiandehkordi R, Quinton JN, Surridge BW. Long-term effects of drinking-water treatment residuals on dissolved phosphorus export from vegetated buffer strips. Environmental science and pollution research international. 2014 Nov 13.

The export of dissolved phosphorus (P) in surface runoff from agricultural land can lead to water quality degradation. Surface application of aluminium (Al)-based water treatment residuals (Al-WTRs) to vegetated buffer strip (VBS) soils can enhance P removal from surface runoff during single runoff events. However, the longer-term effects on P removal in VBSs following application of products such as Al-WTR remain uncertain. We used field experimental plots to examine the long-term effects of applying a freshly generated Al-WTR to VBSs on dissolved P export during multiple runoff events, occurring between 1 day and 42 weeks after the application of Al-WTR. Vegetated buffer strip plots amended with Al-WTR significantly reduced soluble reactive P and total dissolved P concentrations in surface runoff compared to both unamended VBS plots and control plots. However, the effectiveness of Al-WTR decreased over time, by approximately 70 % after 42 weeks compared to a day following Al-WTR application. Reduced performance did not appear to be due to drying of Al-WTR in the field. Instead, the development of preferential flow paths as well as burying of Al-WTR with freshly deposited sediments may explain these observations. Better understanding of the processes controlling long-term P removal by Al-WTR is required for effective management of VBSs.

Click here for paper (fee).

Conjugative Plasmids Convey Antibiotic Resistance Genes

Laroche-Ajzenberg E, Flores Ribeiro A, Bodilis J, Riah W, Buquet S, Chaftar N, Pawlak B. Conjugative multiple-antibiotic-resistance plasmids in E. coli isolated from environmental waters contaminated by human faecal wastes. Journal of Applied Microbiology. 2014 Nov 12. doi: 10.1111/jam.12691.

AIMS: To better understand the involvement of faecal contamination in the dissemination of antibiotic-resistance genes, we investigated the genetic supports of resistances in nine multi-resistant E. coli strains originating from human faecal contamination, and isolated from three different aquatic environments used for producing drinking water.

METHODS AND RESULTS: Seven strains harboured at least one large plasmid that we have characterized (size, antibiotic resistance patterns, incompatibility group, capacity of autotransfer, presence of integron). Most of these plasmids were conjugative and carried numerous resistances. One of the plasmids studied, belonging to the IncP incompatibility group, was able to transfer by conjugation to Pseudomonas fluorescens and Aeromonas sp. Only two of the plasmids we studied carried class 1 and/or 2 integron(s).

CONCLUSIONS: Conjugative plasmids isolated from multi-resistant E. coli strains explained most of the resistances of their host strains and probably contribute to the spread of antibiotic resistance genes coming from human faecal contamination.

SIGNIFICANCE AND IMPACT OF THE STUDY: These results highlight the key role played by plasmids in the multi-resistance phenotype of faecal bacteria and the diversity of these genetic structures. Contaminated water, especially accidentally contaminated drinking water, could be a path back to humans for these plasmids.

Click here for paper (fee).

UV Radiation and Aquatic Ecosystems: A Nice Story

This article makes some good points about the science of UV radiation. But extrapolating to generalized assertions about the future status and fate of natural aquatic systems from “climate change” goes a bit too far. But it’s a nice story.

We must remember, UV radiation was around and having its effects on aquatic ecosystems for many centuries before any of these researcher were born. What may be “new” discoveries to them (and us) are certainly not new for the ecosystem. To take such a limited knowledge base and extrapolate to the future (e.g., long term effects of warmer waters) is rather premature, if not silly. Especially in view of the extreme cold many natural aquatic systems are currently experiencing. Seems to me some warming would be a good thing….

Häder DP, Williamson CE, Wängberg SA, Rautio M, Rose KC, Gao K, Helbling EW, Sinha RP, Worrest R. Effects of UV radiation on aquatic ecosystems and interactions with other environmental factors. Photochemical and Photobiological Sciences. 2014 Nov 12.

UV reactions

Interactions between climate change and UV radiation are having strong effects on aquatic ecosystems due to feedback between temperature, UV radiation, and greenhouse gas concentration. Higher air temperatures and incoming solar radiation are increasing the surface water temperatures of lakes and oceans, with many large lakes warming at twice the rate of regional air temperatures. Warmer oceans are changing habitats and the species composition of many marine ecosystems. For some, such as corals, the temperatures may become too high. Temperature differences between surface and deep waters are becoming greater. This increase in thermal stratification makes the surface layers shallower and leads to stronger barriers to upward mixing of nutrients necessary for photosynthesis. This also results in exposure to higher levels of UV radiation of surface-dwelling organisms. In polar and alpine regions decreases in the duration and amount of snow and ice cover on lakes and oceans are also increasing exposure to UV radiation. In contrast, in lakes and coastal oceans the concentration and colour of UV-absorbing dissolved organic matter (DOM) from terrestrial ecosystems is increasing with greater runoff from higher precipitation and more frequent extreme storms. DOM thus creates a refuge from UV radiation that can enable UV-sensitive species to become established. At the same time, decreased UV radiation in such surface waters reduces the capacity of solar UV radiation to inactivate viruses and other pathogens and parasites, and increases the difficulty and price of purifying drinking water for municipal supplies. Solar UV radiation breaks down the DOM, making it more available for microbial processing, resulting in the release of greenhouse gases into the atmosphere. In addition to screening solar irradiance, DOM, when sunlit in surface water, can lead to the formation of reactive oxygen species (ROS). Increases in carbon dioxide are in turn acidifying the oceans and inhibiting the ability of many marine organisms to form UV-absorbing exoskeletons. Many aquatic organisms use adaptive strategies to mitigate the effects of solar UV-B radiation (280-315 nm), including vertical migration, crust formation, synthesis of UV-absorbing substances, and enzymatic and non-enzymatic quenching of ROS. Whether or not genetic adaptation to changes in the abiotic factors plays a role in mitigating stress and damage has not been determined. This assessment addresses how our knowledge of the interactive effects of UV radiation and climate change factors on aquatic ecosystems has advanced in the past four years.

Click here for paper (Open Access).

Soil Fluoride Spiking Effects on Olive Trees

Zouari M, Ben Ahmed C, Fourati R, Delmail D, Ben Rouina B, Labrousse P, Ben Abdallah F. Soil fluoride spiking effects on olive trees (Olea europaea L. cv. Chemlali). Ecotoxicology and Environmental Safety. 2014 Oct;108:78-83. doi: 10.1016/j.ecoenv.2014.06.022.

A pot experiment under open air conditions was carried out to investigate the uptake, accumulation and toxicity effects of fluoride in olive trees (Olea europaea L.) grown in a soil spiked with inorganic sodium fluoride (NaF). Six different levels (0, 20, 40, 60, 80 and 100mM NaF) of soil spiking were applied through NaF to irrigation water. At the end of the experiment, total fluoride content in soil was 20 and 1770mgFkg(-1) soil in control and 100mM NaF treatments, respectively. The comparative distribution of fluoride partitioning among the different olive tree parts showed that the roots accumulated the most fluoride and olive fruits were minimally affected by soil NaF spiking as they had the lowest fluoride content. In fact, total fluoride concentration varied between 12 and 1070µgFg(-1) in roots, between 9 and 570µgFg(-1) in shoots, between 12 and 290µgFg(-1) in leaves, and between 10 and 29µgFg(-1) in fruits, respectively for control and 100mM NaF treatments. Indeed, the fluoride accumulation pattern showed the following distribution: roots>shoots>leaves>fruits. On the other hand, fluoride toxicity symptoms such as leaf necrosis and leaf drop appeared only in highly spiked soils (60, 80 and 100mM NaF).

Click here for paper (fee).

Groundwater Quality in the Bakken Formation Production Area

McMahon PB, Caldwell RR, Galloway JM, Valder JF, Hunt AG.Quality and Age of Shallow Groundwater in the Bakken Formation Production Area, Williston Basin, Montana and North Dakota. Ground water. 2014 Nov 13. doi: 10.1111/gwat.12296.

The quality and age of shallow groundwater in the Bakken Formation production area were characterized using data from 30 randomly distributed domestic wells screened in the upper Fort Union Formation. Comparison of inorganic and organic chemical concentrations to health based drinking-water standards, correlation analysis of concentrations with oil and gas well locations, and isotopic data give no indication that energy-development activities affected groundwater quality. It is important, however, to consider these results in the context of groundwater age. Most samples were recharged before the early 1950s and had 14 C ages ranging from <1000 to >30,000 years. Thus, domestic wells may not be as well suited for detecting contamination associated with recent surface spills as shallower wells screened near the water table. Old groundwater could be contaminated directly by recent subsurface leaks from imperfectly cemented oil and gas wells, but horizontal groundwater velocities calculated from 14 C ages imply that the contaminants would still be less than 0.5 km from their source. For the wells sampled in this study, the median distance to the nearest oil and gas well was 4.6 km. Because of the slow velocities, a long-term commitment to groundwater monitoring in the upper Fort Union Formation is needed to assess the effects of energy development on groundwater quality. In conjunction with that effort, monitoring could be done closer to energy-development activities to increase the likelihood of early detection of groundwater contamination if it did occur.