Acute Physicochemical Effects in a Large River-Floodplain System Associated with the Passage of Hurricane Gustav

On 1 September 2008, Hurricane Gustav passed over the Atchafalaya River Basin (ARB) in south-central Louisiana. Anticipating physicochemical shifts due to concentrated precipitation and wind stress generated by this strong category 2 storm, we deployed a continuous recording multiparameter water quality sonde in a southern ARB bayou 3 days prior to storm arrival to document conditions before, during, and after hurricane landfall. Quarter-hourly physicochemical measurements taken over a 2-week period indicated that dissolved oxygen (DO), pH, and specific conductance all reached annual lows immediately following storm passage. The most pronounced poststorm fluctuation involved DO. Daily mean DO concentration dropped to hypoxic level (DO-2 mg/L) within 3 days of landfall, followed by near anoxic conditions within 5 days that resulted in extensive system-wide fish kills. Within 6 weeks, however, DO returned to, and pH was near pre-storm levels. To evaluate the impact of Hurricane Gustav on ARB physicochemistry, we contrasted data on DO, pH, temperature, and specific conductance collected from 16 lower ARB sampling sites over a 54-day interval prior to storm landfall with data collected during a 45-day post-storm period. Results indicated that water quality was highly dissimilar (P\u3c0.0001) between the two periods. © Society of Wetland Scientists 2011

Metabolic signatures associated with environmental pollution by metals in Doñana National Park using P. clarkii as bioindicator

Bioindicators can reflect the effects of pollutants on their metabolism, being widely used to assess environmental stress. In this sense, the crab Procambarus clarkii has been previously proposed to monitor the contamination in Doñana National Park (southwest Spain) using conventional biomarkers. In this work, a metabolomic approach based on direct infusion mass spectrometry, which allows an easy and quick study of a large number of metabolites in a single run, was used for pollution assessment of this area, considering the biological response of this organism to contamination. In addition, metal accumulation in crab tissues was determined. Thus, the integrated analysis of metabolomic and metallomic data enabled the study of metabolic response of the organism against pollution. Several metabolites were discovered as potential biomarkers of pollution, such as decreased levels of carnosine, alanine, niacinamide, acetoacetate, pantothenic acid, ascorbate, glucose-6-phosphate, arginine, glucose, lactate, phospholipids, and tryglicerides, as well as elevated levels of acetyl carnitine, phosphocholine, choline, and uric acid. In this way, metal-induced toxicity could be related to metabolic impairments, principally oxidative stress, metabolic dysfunction, and dyslipidemia.CTM2012-38720-C03-01, P008-FQM-3554, P009-FQM-4659info:eu-repo/semantics/publishedVersio