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Arthrospira platensis has very high absorption by photosynthesis processes of CO2 fixation and release of oxygen. It was becoming significant microalgae for biological wastewater treatment because of their bodies' accumulation of nutrients, heavy metals, organic and inorganic compounds used as the main source of their life production in wastewater. The objective of this study was to determine the ability of Arthrospira platensis for bioremediation by biosorption of heavy metals present in mining wastewater. Microalgae culture condition parameters were: temperature fixed at 30°C-35°C; the light was 1,000-2,000 lux set for 12 h d-1 and 12 h night-1; pH; turbidity was 25-40 NTU. Biosorption was influenced by sorbent concentration (5-60 g L-1), pH 2.0-9.0, and contact time (60 min) for heavy metals removal. It was related to nutrients consumption from wastewater with microalgae growth production by biosorption and takes place with separation of micronutrients (Zn, Cu, and Fe) and toxic metal such (Pb) from microalgae samples in a solution using centrifugation. The photosynthesis process was very suitable, that why chlorophyll productivity was very high. At low light intensity (1,000-1,400 lux), Arthrospira platensis consumed a high amount of nutrients (COD, TP, TN, ammonium) for growth. At high light intensity (2,000 lux), cell productivity, biomass productivity, growth rate, protein content, and energy value were very high. The effect of biosorbent on heavy metals removal from wastewater provides the following results: zinc adsorbed decreased from 4.08 to 2.1216 mg g-1; iron from 6.03 to 0.6 mg g-1; copper from 5.02 to 0.75 mg g-1; and lead decreased from 7.04 to 0.98 mg g-1. The effect of pH on metals biosorption was: sulfates (SO4) 93%, iron Fe 99%, lead Pb 95%, zinc Zn 52%, copper Cu 94%) removal efficiency with pH above 7.1. Heavy metals biosorption from wastewater was depended on sorbent concentration, pH, and contact time. The presence of multi-metal in culture systems decreases zinc adsorption, compared to the single metal one. The previous study was Arthrospira platensis biomass removed 50% of zinc from wastewater, which means that higher concentrations of other metal ions present in the wastewater don't affect the removal of zinc ions from the wastewater. The removal of zinc ions from the mining wastewater was about 52% in the current study. [ABSTRACT FROM AUTHOR]

Phylogeographic barriers, together with habitat loss and fragmentation, contribute to the evolution of a species’ genetic diversity by limiting gene flow and increasing genetic differentiation among populations. Changes in connectivity can thus affect the genetic diversity of populations, which may influence the evolutionary potential of species and the survival of populations in the long term. We studied the genetic diversity of the little known Northern rufous mouse lemur (Microcebus tavaratra), endemic to Northern Madagascar. We focused on the population of M. tavaratra in the Loky-Manambato region, Northern Madagascar, a region delimited by two permanent rivers and characterized by a mosaic of fragmented forests. We genotyped 148 individuals at three mitochondrial loci (D-loop, cytb, and cox2) in all the major forests of the study region. Our analyses suggest that M. tavaratra holds average genetic diversity when compared to other mouse lemur species, and we identified two to four genetic clusters in the study region, a pattern similar to that observed in another lemur endemic to the region (Propithecus tattersalli). The main cluster involved samples from the two mountain forests in the study region, which were connected until recently. However, the river crossing the study region does not appear to be a strict barrier to gene flow in M. tavaratra. Finally, the inferred demographic history of M. tavaratra suggests no detectable departure from stationarity over the last millennia. Comparisons with codistributed species (P. tattersalli and two endemic rodents, Eliurus spp.) suggest both differences and similarities in the genetic clusters identified (i.e., barriers to species dispersal) and in the inferred demographic history. These comparisons suggest that studies of codistributed species are important to understand the effects of landscape features on species and to reconstruct the history of habitat changes in a region. [ABSTRACT FROM AUTHOR]

Despite the fact that lemurs are the most threatened group of mammals and live in one of the world's richest biodiversity hotspots, there are still lemur lineages and regions of Madagascar that suffer from a lack of naturalistic data. This is particularly striking for the genus Phaner as well as for many unprotected forests of Northeastern Madagascar. We detected the presence of Phaner in the isolated lowland dry forest of Analafiana, located south of the Manambato River and close to the city of Vohémar. Little is known about the presence of Phaner in this region. The only record of Phaner in the area around Analafiana comes from museum specimens (Groves and Tattersall, 1991) geographically assigned to Vohémar and identified as belonging to a "doubtful subspecies". Here we provide morphological and genetic (mitochondrial DNA) data for a single juvenile individual captured in Analafiana. We compare our sequence data to the only four Phaner sequences publicly available: two P. electromontis individuals sampled in Montagne d'Ambre and Ankarana, and two other from P. pallescens and P. parienti species. We find that the new mtDNA sequence is divergent from the two P. electromontis sequences, but closer to these than other Phaner sequences. We also note that the Analafiana Phaner individual is morphologically more similar to P. electromontis than to the other species. Altogether, this data suggests this unique and isolated population of Phaner survives in the unprotected Analafiana forest in northeastern Madagascar. It is urgent to carry out more genetic, behavioral, acoustic, and demographic research in this region and on this population, whose exact taxonomic status should be urgently clarified. Our results strongly suggest that Analafiana's Phaner population likely holds the memory of a unique evolutionary history. [ABSTRACT FROM AUTHOR]

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Copyright of Lemur News is the property of Lemur News and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Lemur News is the property of Lemur News and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)