[en] Antibiotic residues pose a threat to the health of aquatic organisms. The effects and accumulation of antibiotic ciprofloxacin (CIP) in a floating macrophyte (Eichhornia crassipes) under hydroponic conditions were investigated. It was found that E. crassipes exposure to CIP (< 1000 μg L⁻¹) could maintain a stable photosynthesis efficiency. In response to CIP stress, catalase and peroxidase activities of leaves were 7.24–37.51 nmol min⁻¹ g⁻¹ and 98.46–173.16 U g⁻¹, respectively. The presence of CIP did not inhibit the growth of the plant. After 14 days of exposure, tender leaves became white and withered, ascribed to the decline of chlorophyll content and chlorophyll fluorescence parameters. The CIP concentrations, absorbed by E. crassipes, were highest in the roots, followed by white aerial parts and green aerial parts at CIP concentrations of 100 and 1000 μg L⁻¹. These findings demonstrated that E. crassipes could absorb and tolerate CIP in a limited time-scale and imply an alternative solution for phytoremediation in water bodies contaminated with antibiotics.

[en] Published in summary form only

[en] The first findings and distribution of larvae of the species Diplophos proximus, family Gonostomatidae, in the Pacific of Colombia are presented. The analyzes show larvae between Bahia Malaga and Tumaco (limits with Ecuador), with low abundances during the seasons of September 2003 and 2005, July and December 2010, December 2013, February-March 2014, June 2016 and June and September 2017, always collected at stations located more than 113 km away from the coast and around Malpelo island. The larvae are elongated and have noticeable changes during development, initially oval eyes, poorly pigmented body without photophores and finally rounded eyes, dorsal pigments and photophores during transformation. The present work contributes with information about distribution and ecology of larvae of D. proximus becoming the first records of catches for the Colombian Pacific, including the description of the larval stages found.

[en] The first observation is reported of an enkaryote micro-organism (chlamydomona), collected in samples from the Rodrigo de Freitas lagune in Rio de Janeiro, which responds to the magnetic field in a similar way as the magnetotactic bacterias. (L.C.)

[en] Primary production in squads ecosystems is the organic production of phytoplankton which is the primary food source for others aquatic organisms. The measurement of primary production in the sea can be measured by many methods but the use of ¹⁴ C-method for measurement of primary production is very good. The principle of ¹⁴ C-technique is addition of ¹⁴ CO₂ in the form of Na H ¹⁴ CO₂ to the water sample. Then incubate the bottle of water sample in the sea or in the incubator with light for a certain period. After incubation, the total organic production can be measured from algal uptake ¹⁴ C. Phuket Marine Biological Center has used the ¹⁴ C-technique for measurement the primary production in the Andaman Sea in order to know how much of the primary food source are available in this area. The average value of primary production in the Andaman Sea was 850 mg C/m^-3/d^-1. It can be encountered as an important for marine food source with high primary production

[en] Physico-chemistry, radioactive toxicity of concentration factors for the main radionuclides released into the marine environment. Environmental levels and biological function of the stable isotope

[en] The use of live animal gamma radioisotope tracer techniques in the field of ecotoxicology allows laboratory studies to accurately monitor contaminant biokinetics in real time for an individual organism. However, methods used in published studies for aquatic organisms are rarely described in sufficient detail to allow for study replication or an assessment of the errors associated with live animal radioanalysis to be identified. We evaluate the influence of some important methodological deficiencies through an overview of the literature on live aquatic animal radiotracer techniques and through the results obtained from our radiotracer studies on four aquatic invertebrate species. The main factors discussed are animal rinsing, radioanalysis and geometry corrections. We provide examples of three main techniques in live aquatic animal radiotracer studies to improve data quality control and demonstrate why each technique is crucial in interpreting the data from such studies. The animal rinsing technique is also relevant to non-radioisotope tracer studies, especially those involving nanoparticles. We present clear guidance on how to perform each technique and explain the importance of proper reporting of the validation of each technique for individual studies. In this paper we describe methods that are often used in lab-based radioecology studies but are rarely described in great detail. We hope that this paper will act as the basis for standard operating procedures for future radioecology studies to improve study replication and data quality control. - Highlights: • Live radiotracer techniques provide real-time analysis of contaminant accumulation. • Technique allows for greater data generation from fewer animals. • Methods described in literature are often not detailed enough for study validation. • Procedures for animal rinsing, live radioanalysis and geometry correction described.

[en] This paper presents the combined efforts of the Food and Nutrition Research Institute (FNRI) and the Philippine Atomic Energy Commission (PAEC) as part of the Project NSDB 7401 Ag ''Nutritionwide Survey of Mercury and Other Heavy Metals Pollution in Philippine Waters, Aquatic Life and Sediments.'' Lead and cadmium analysis was done at PAEC by Differential Pulse Anodic Stripping Voltametry (DPASV) while the analysis of copper and zinc was done at FNRI by Atomic Absorption Spectrophotometry (AAS). Fish and other aquatic samples were collected by the Bureau of Fisheries and Aquatic Resources. Mercury analysis by four cooperating agencies, Ateneo University, FNRI, National Pollution Control Commission and PAEC on aquatic life, water and sediments are reported elsewhere. Lead and cadmium are recognized as toxic metals and incidences of poisoning from environmental pollution are well-known and so are the clinical symptoms of this poisoning. Although copper and zinc are basically essential trace elements, they are toxic when ingested above certain concentrations and their presence in the environment at elevated concentrations connotes pollution from industrial sources. (author)

[en] A qualitative survey of the macroscopic algae of the benthic flora in the area, of Saco do Piraquara de Fora follow the seasonality of species, and indication of the most abundant group in the sites of collection, are presented. (E.G.)

[en] Carbon-13 analyses were determined for brachiopods and particulate organic matter from Fiordland waters. Brachiopod delta ¹³$⁰C are about ^-18 per mille which is significantly enriched in ¹³C relative to the particulate matter (about -23 per mille) and different from local terrestrial matter (about -28 per mille). There is no carbon-13 evidence for non-marine food in the diet of brachiopods