Trace element content in soil after a sediment-laden flood in northern Chile

Purpose

Arid and hyper-arid zones worldwide are reservoirs of chemical compounds, among them are various trace elements. With climate change, abnormal precipitation is occurring in arid and hyper-arid mountainous zones, which in turn is increasing the displacement of trace elements from mountainous to populated areas. The objective of this study was to evaluate trace element displacement of a sediment-laden flood in the Copiapó River Basin on March 24–25, 2015.

Materials and methods

Sixty topsoil samples were taken from 20 agricultural fields. Soil organic matter content, pH, electrical conductivity, and particle size were determined according to accepted procedures in Chile. Samples were acid-digested to determine total Al, As, Cd, Cr, Cu, Fe, Hg, Mn, Mo, Ni, Pb, Se, and Zn content by flame atomic absorption spectroscopy. Hydride generation AAS was used for As and Se determination, and Hg was quantified by cold vapor AAS. Detection limits were 0.2, 0.05, 0.1, and 5.0 mg kg^?1 for Cd, Hg, Se, and Mo, respectively. Correlation and principal component analyses were made, and theoretical distribution functions were fitted to each element.

Results and discussion

Metal concentration showed a strong correlation between SOM and particle size, explaining the first component from the principal component analysis. All trace elements correlated well between each other except for Mo and Se. Mo values were consistently below detection levels (<5.0 mg kg^?1). Expected values for the elements were (95% of probability): 13–37 g Al kg^?1, 10–50 mg As kg^?1, <0.2–0.6 mg Cd kg^?1, 13–25 mg Cr kg^?1, 27–281 mg Cu kg^?1, 27–40 g Fe kg^?1, <0.05–6.5 mg Hg kg^?1, 516–1.080 mg Mn kg^?1, 7–24 mg Ni kg^?1, 13–50 mg Pb kg^?1, 0.2–0.6 mg Se kg^?1, and 61–172 mg Zn kg^?1. Concentrations of As, Cu, and Hg were consistently above national standards.

Conclusions

The authors conclude that the trace element contents in sediments deposited by the event are within expected values based on soil data in Chile.

     

Health evaluation of a radiocollared population of free-ranging Baird's tapirs (Tapirus bairdii) in Costa Rica.

The health of a population of free-ranging tapirs (Tapirus bairdii) inhabiting Corcovado National Park, Costa Rica, was assessed as part of an ongoing ecologic study. Nineteen tapirs were immobilized between March 1997 and February 2000, and samples of blood, skin biopsies, and ectoparasites were collected. Ticks were identified as Amblyomma oblongoguttatum or A. coelebs. Hematology and serum biochemistry results suggest statistically significant differences between free-ranging and captive populations that should be interpreted with caution in view of inherent environmental differences between the two populations. Five of 17 animals tested positive for Leptospira bratislava, and 12 individuals tested positive for Venezuelan equine encephalitis. One of nine skin biopsies examined was abnormal and diagnosed as leukoderma. This report represents the first health assessment of a free-ranging population of tapirs.     

Congenital erythropoietic porphyria in an African hedgehog (Atelerix albiventris).

A 6-mo-old, male African hedgehog (Atelerix albiventris) presented with a history of pink urine and demonstrating pink-colored teeth and mild hepatomegaly on examination. Urinalysis revealed no physical, chemical, or cellular abnormalities other than a pink color and fluorescence under ultraviolet light (UV). Also under UV, intense fluorescence of teeth, feet, and spines was noted. Porphyria was suspected. Spectrophotometric evaluation of urine showed extremely elevated levels of copro- and uroporphyrins. Analysis of the urine by thin-layer chromatography showed an abnormal pattern of excreted porphyrin intermediates. Urine high-performance thin-layer chromatography showed that excreted porphyrins were 90-95% of the type-I isomeric form, suggestive of congenital erythropoietic porphyria.     

Calvaria and orbital metastases of pulmonary adenosquamous carcinoma in a cat: a diagnostic challenge

An 11-year-old cat with a 4-month history of lethargy, inappetence, dysphagia, partial mandibular paralysis and weight loss, was euthanized due to the rapid deterioration of his condition. Post-mortem radiographic examination revealed severe bone lysis of the left zygomatic arch, temporal and parietal bones. Magnetic resonance imaging of the head showed a large isointense mass of the left side of the skull associated with extensive lysis of the parietal and temporal bones and destruction of the adjacent tympanic bulla. Gross and histological examinations revealed a pulmonary adenosquamous carcinoma of the left lung, with metastases to the spleen, liver, mesenteric lymph nodes, mesentery, diaphragm, abdominal aorta, left orbit and calvaria. No limb or digit metastases were detected.     

Sustainable water treatment in aquaculture – photolysis and photodynamic therapy for the inactivation of Vibrio species

Species of the genus Vibrio have been recognized as one of the most significant pathogens in aquaculture farming, causing mass mortality of farmed stocks. Photodynamic Antimicrobial Chemotherapy (PACT) with singlet oxygen (¹O₂) has been identified as a powerful and sustainable water treatment method for pathogen eradication. In this study, the efficiencies of photolytic and photodynamic disinfection protocols were studied with two Vibrio species, Vibrio parahaemolyticus and Vibrio owensii. The selected microorganisms were successfully cultivated in marine broth and irradiations were performed with ~10⁸ bacteria mL^?1. Treated samples were monitored for bacterial regrowth for up to 7 days. Photolysis experiments were initially conducted with UV‐A, UV‐B for up to 2 h and visible (VIS) light for up to 24 h. Of these, only irradiation with UV‐B light for at least 45 min was efficient in controlling Vibrio. Irradiations with VIS light were subsequently repeated under PACT conditions in dose?response experiments with two water‐soluble porphyrins, [T₄(MePy)P] and [TPPS₄]. Disinfections of samples were successful for both porphyrin types at minimum concentrations of 10 μM and 24 h of irradiation.     

Application of Tamarind Waste Extracts to Improve the Antioxidant Properties of Tamarind Nectars

Plant Foods for Human Nutrition - Tamarind fruits are consumed worldwide and their seeds have an underexploited potential. We assessed the effect of the addition of a freeze-dried aqueous of...     

Identification and quantification of stilbenes in fruits of transgenic tomato plants (Lycopersicon esculentum Mill.) by reversed phase HPLC with photodiode array and mass spectrometry detection

Reversed-phase high-performance liquid chromatography (RP-HPLC) with photodiode array (PDA) and mass spectrometry (MS) detection was employed to study the accumulation of stilbenes and other naturally occurring polyphenol intermediates of flavonoid pathway in tomato fruits of plants genetically modified to synthesize resveratrol. The transgenic tomato fruits were obtained by overexpression of a grapevine gene encoding the enzyme stilbene synthase in tomato plants (Lycopersicon esculentum Mill.). Stilbenes and flavonoids, either glycosylated or free, were simultaneosly identified by electrospray interface (ESI)-MS in negative ionization mode and were quantified by PDA detection at the wavelength corresponding to their maximum absorbance. The two detectors were coupled online with an HPLC system utilizing a narrow-bore C18 reversed-phase column, which was eluted by a multistep gradient of increasing concentration of acetonitrile in water containing 0.5% (v/v) formic acid. The results of these analysis revealed that the genetic modification of the tomato plants originated different levels of accumulation of four stilbenes (i.e., trans- and cis-piceid and trans- and cis-resveratrol) in their fruit depending on the stages of ripening. Either at immature or at mature stages of ripening the stilbenes were preferentially accumulated in the fruit peel as the glycosylated form. The highest amount of trans-piceid and trans-resveratrol were found in the peel of fruits harvested at mature stage of ripening. The variations in the levels of rutin, naringenin, and chlorogenic acid found in the samples extracted from the fruits of transgenic tomato plants, in comparison to that determined in the control lines, seemed to be related to the genetic transformation, whose effect on the flavonoid biosynthetic pathway needs to be elucidated by additional studies.     

Operational Effectiveness of Centralized Nursery for Small-Scale Forestry in San Carlos City, Negros Occidental, the Philippines: Lessons Learned in Seedling Production for Commercial Energy Crop Plantations

One way to maximize potential income of smallholder tree farmers is to ensure high quality of planting material. In San Carlos City, Negros Occidental, the Philippines, great importance is placed on seedling quality because Energy Crop Plantations (ECPs) managed under a Short-Rotation Coppice (SRC) system will involve a single planting for several three-year coppices. High seedling quality requires superior seed provenances and seedling propagation methods. Throughout the establishment of the nursery facility, and the propagation of planting stock, data collection, reporting and database systems have been designed to capture relevant costs and technical information. Training has been provided to nursery personnel and labourers to enable them to operate the nursery and produce high quality seedlings. This paper reports a practical operational evaluation of all materials and procedures followed in nursery establishment and seedling production. Economies of scale in nursery operation are achieved at a production level of at least 90,000 seedlings per planting season of three months in the year. The production cost is estimated at PhP 3.57/seedling, excluding the cost of the nursery infrastructure and overheads. Cost comparison with decentralized or contracted nurseries shows little variation at a total cost of PhP 4.12/seedling. However, with these alternative nursery arrangements there is high risk of producing low quality seedlings by possible reduction of inputs and skipping quality enhancement procedures to reduce production cost.     

Phosphorus availability and grass growth in biochar-modified acid soil: A study excluding the effects of soil pH

The low efficiency of phosphorus fertilization in weathered soils can limit plant development. The application of biochars in these areas has been seen as an important way to increase the efficiency of phosphorus fertilization and to promote better plant growth. However, biochars are alkaline materials that can increase soil pH and thus change the nutrient dynamics, which has been often ignored in studies of this nature. Here, all treatments had their pH standardized at 6.1 to eliminate the influence of pH on biochar application responses. The main goal of this study was to evaluate the real potential of coffee straw and eucalyptus bark biochars, produced under different pyrolysis temperatures, in the optimization of phosphorus fertilization and the development of Brachiaria brizantha. A greenhouse experiment was set up in a 2 × 2 × 5 factorial scheme, conducted for 120 days. The biochars, prepared from coffee straw and eucalyptus bark at 350 and 600°C, were applied at five rates in a Red-Yellow Oxisol. The application of biochars may reduce the demand for nutrients and correctives, optimize phosphorus fertilization and improve the development of Brachiaria brizantha, but this ability depends on the raw material and the pyrolysis temperature used in its production. All analysed biochars can contribute to higher tillering and dry matter production, but only coffee straw biochars and eucalyptus bark biochar produced at 350°C were efficient in the optimization of phosphorus fertilization until 120 days of cultivation of Brachiaria brizantha.