Hunting for Life on Mars by Studying Life on Earth

Modern-day Mars is a dry, harsh environment with no surface water, but billions of years ago it might have been water-rich, like Earth. Scientists believe that, as water was lost on Mars, the remaining water would have become increasingly salty and rich in sulphur. By researching environments on Earth with a similar chemistry, we can develop hypotheses about whether life could have existed on Mars. In our research, we studied Colour Peak, a sulphur-rich, salty spring system in the Canadian High Arctic. This environment contains bacteria that use sulphur to get their energy. By studying water and sediment samples from this region, we confirmed that bacteria that used sulphur as an energy source could potentially have lived on Mars. These results can help scientists who are analysing data from Mars missions to identify evidence of former life on Mars.

Assessment of Surface Water Quality in the Podu Iloaiei Dam Lake (North-Eastern Romania): Potential Implications for Aquaculture Activities in the Area

The Podu Iloaiei Dam Lake located on the Bahluet River from Bahlui hydrographic basin, north-eastern Romania, is one of the most important water resources used for aquaculture activities in the region of interest. In the present study, the chemical composition related to water-soluble ions and elements was assessed in both water and sediment samples collected from the area of interest during July 2017 and October 2017, representative months for warm and cold seasons, respectively. Water-soluble ions (H3C2O2−, HCO2−, C2O42−, F−, Cl−, NO2−, Br−, NO3−, SO42−, Li+, Na+, NH4+, K+, and Ca2+) were analyzed by ion chromatography, while inductively coupled plasma mass spectrometry was used to quantify water-soluble fractions of elements (Be, B, Mg, Al, Ti, V, Cr, Mn, Fe, Co, Ni, Cu, Zn, Ga, Ge, Rb, Sr, Mo, Ru, Pd, Ag, Cd, Sn, Sb, Te, Ba, Ir, Tl, Pb, Bi, and U). Evidence was obtained on the contributions of both anthropogenic and natural (pedologic) related sources in controlling the chemical composition of the water and sediment samples in the area. Analysis of Piper diagrams revealed the existence of CO32−/HCO3− and Ca2+/Mg2+ as dominant species for the sediment samples. The interest water pool was found to be oligotrophic over the warm period and eutrophic over the cold period. Overall, abundances and the association of chemical species in the area seemed to be controlled by a complex interplay between the water body’s main characteristics, meteorological factors, and anthropogenic activities. Moreover, the present results suggest that precautions should be taken for physicochemical parameter monitoring and prevention acts for surface water quality assurance in order to control the potential negative influence of some chemical parameters on fish productivity. Reported data also have a high potential to be used by experts in the field of developing lake water management policies for a sustainable exploitation of various aquatic systems.

Bacterial Diversity of Water and Sediment Samples from Gull Point State Park (West Okoboji, Iowa) Determined Using 16S rRNA Gene Amplicon Sequencing

Gull Point State Park is located on a peninsula on the west shore of West Okoboji Lake (Iowa, USA). It is the primary state park in the Iowa Great Lakes region. Sediment and water samples from three locations at the Gull Point pond were analyzed for their microbial composition.

Heavy Metals Analysis and Health Risk Assessment of Three Fish Species, Surface Water and Sediment Samples in Ogbaru Axis of River Niger, Anambra State, Nigeria

Human activities on environmental resources have negatively affected floras and faunas in maintaining fair balance. In this research study, selected heavy metals (Al, As, Cd, Cr, Cu, Fe, Hg, Pb, Ni, Zn) concentration in three fish species (Clarias gariepinus, Heterotis niloticus and Anguilla labiate), surface water and sediment samples in Ogbaru axis of River Niger, Anambra State, Nigeria. We evaluated the samples using atomic absorption spectrophotometer (AAS). The result of heavy metals (Cu, Fe, Zn, Ni, Pb, Cd, Al, Cd) analysis in fish samples showed that Cr was detected in Clarias garipinus and Anguilla labiate with a concentration of 0.001mg/kg in both species but was not detected in Heterotis niloticus. Hg and Al were not detected in Anguilla labiate but both metals were detected in the other fish species with a mean concentration of 0.311mg/kg and 0.019mg/kg respectively for Clarias garipinus and 0.001mg/kg and 0.005mg/kg respectively for Heterotis niloticus. In decreasing order, the heavy metal concentration in Clarias garipinus in increasing order of Cu >Fe > Ni > Hg > Pb > Zn > As > Cd > Al > Cr, while Heterotis niloticus followed the order Cu > Zn > Fe > Ni > Pb > Cd > Al > As > Hg > Cr, and Anguilla labiate followed the pattern of Cu > Fe > Zn > Ni > Pb > Cd > Cr > As > Hg > Al. For surface water, As (0.005mg/l), Cd (0.032 mg/l), Cr (0.099 mg/l), Cu (0.186 mg/l), Fe (2.308 mg/l), Hg (1.501 mg/l) and Pb (0.724 mg/l) showed high concentration for the raining season compared to dry season, as Al (0.246 mg/l), Ni (0.773 mg/l) and Zn (2.903 mg/l) were dominant during dry season, while sediment samples of Cr (0.112 mg/kg), Cu (0.029 mg/kg), Ni (0.945 mg/kg) and Pb (0.039 mg/kg) concentration in raining season were higher than dry season and vice versa for other As, Cd, Fe, Hg, Zn. Correlation matrices showed positive value showing that heavy metals were from a similar source with migration route and vice versa for negative correlation. Health and exposure risk assessment was conducted for carcinogenic and non-carcinogenic exposure in adults and children, where the cumulative cancer risk was within USEPA regulatory standard (1.0E-6 – 1.0E-04) and cumulative hazard index were above 1 for adults (2.02) and children (4.93), implying that children are at risk of having adverse health issues compared to adults. Therefore, there is a need for regulatory advocacy and special care to mitigate anthropogenic release and safeguard the environment.

Determination and Occurrence of Mineralocorticoids in Taihu Lake of China

We developed a sensitive method for monitoring six natural (aldosterone) and synthetic mineralocorticoids (canrenone, spironolactone, 7β-spironolactone, 7α-thio spironolactone, and 7α-thiomethyl spironolactone) in sediment and water using ultra-performance liquid chromatography–electrospray tandem mass spectrometry, and then 30 water and 30 sediment samples were analyzed to reveal their occurrence and distributions in Taihu Lake. All target six mineralocorticoids were detected in sediment and water samples with the detection frequencies as high as 96–100%. The median concentrations of mineralocorticoids ranged from 0.04 ng/L (7α-thiomethyl spironolactone) to 14 ng/L (aldosterone) in water and 0.01 ng/g (7β-spironolactone and canrenone) to 1.44 ng/g (aldosterone) in sediment in dry weight. Natural aldosterone was the predominant mineralocorticoid detected in both water and sediment samples, indicating the mineralocorticoid pollution in Taihu Lake was mainly derived from human and/or animal excrement rather than pharmaceutical industry and usage. Two metabolites 7β-spironolactone and 7α-thio spironolactone were first found in this study. Low ratios of metabolites to spironolactone were observed in sediment (0.05–0.75) in contrast to water (0.12–2.26), indicating that spironolactone was prone to degradation in water phase compared to sediment environment.

Pertumbuhan Api-Api (Avicennia alba) dan Kelimpahan Epifauna Bentik di Kawasan Rehabilitasi Mangrove Desa Kedaburapat Kabupaten Kepulauan Meranti

The research was conducted in July - October 2020. Collection of data A. alba growth and abundance of benthic epifauna was carried out in the mangrove rehabilitated area of Kedabupat village, Kepulauan Meranti Regency. The aims of this study was to analyze the growth (stems height and diameter) of the mangrove A. alba species as a result of rehabilitation and abundance of benthic epifauna in the area. The method used in this research was a survey method, where data was obtained by directly to the research location. The data collected was data on the height and diameter of A. alba stems, density of macro epifauna species, and water quality in the field, then followed by analysis of water and sediment samples in the laboratory. The results showed that the average increace in height of the stem by zone was 6.45-12.93 cm/month, meanwhile the average value of the increase in stem diameter by zone is 1.53-1.85 mm/month. There were 13 epifauna benthic species from 2 classes namely Gastropod and Malacostraca from mangrove rehabilitation. Gastropod class that was Littoraria melanostoma, Nerita balteata and Sphaerassiminea miniata; from the malacostraca class that was Uca coarctata, Metopograpsus latifrons, Ceonobita cavipes, and Clibanarius longitarsus. Benthic epifauna abundance values average ranged from 31.33-52.22 ind/m2.