RESUMO
Coastal ecosystems such as seagrass, mangroves and saltmarshes sequester and store large quantities of carbon in the soil. Carbon sequestration potential of four seagrass species Halophila ovalis, Halodule pinifolia, Syringodium isoetifolium and Halodule uninervis in Pulicat Lake, Andhra Pradesh, India was assessed. The mean seagrass biomass within the seagrass beds in the lake ranged from 1.43 ± 0.06 to 2.01 ± 0.12 Mg/ ha and the total blue carbon storage in the seagrass meadows ranged from 0.49 ± 0.15 to 9.52 ± 0.15 Mg C ha-1 while stored carbon in the sediment ranged from 1.29 ± 0.04 to 11.94 ± 0.15 Mg C ha-1. Regression analysis showed a considerable correlation between seagrass carbon and sediment carbon. Among the environmental parameters analyzed, pH showed significant correlation with seagrass biomass and sediment carbon (P < 0.05). The present study demonstrates the carbon sequestration potential of seagrass ecosystem in the Pulicat Lake.
Assuntos
Alismatales , Ecossistema , Sedimentos Geológicos , Carbono , Lagos , Sequestro de Carbono , ÍndiaRESUMO
Ascidians (Phylum: Chordata) are sessile and filter-feeding marine animal, species identification of ascidians is possible by observing various morphological and anatomical features in various stages of life span. However, this method is labor intensive, time-consuming and very difficult for non-specialists particularly when dealing with field collections. Suborder Aplousobranchiata and Phlebobranchiata is the largest group of tunicates within, morphological and molecular data suggest that Didemnidae and Ascidiidae are monophyletic, but the monophyly of each genus and their phylogenetic relationships are still poorly understood. Therefore, this study was aimed to develop DNA barcodes of ascidians belonging to the orders of Aplousobranchiata and Phlebobranchiata species namely Diplosoma listerianum, Lissoclinum fragile, Didemnum psammatode, Phallusia fumigata and Phallusia ingeria collected from Andaman and Nicobar Islands were sequenced and submitted in Gen Bank. Colony structure, Scanning Electron Microscope (SEM) for spicules of colonial ascidians, larval type and zooids formation were found to be the most useful morphological characters for discriminating the species. Our BLAST results proved D. Listerianum KP842724 (98%) L. fragile KP842726 (100%) D. psammatode KP779902 (99%), P. fumigata KP779904 (99%) and P. ingeria KP842727 (100%) similarity and this is the first report of mitochondrial COI gene of these ascidians from Andaman and Nicobar Islands. We explored the usefulness of CO1 gene sequences for molecular level identification and mtDNA data in assessing a phylogenetic relationship of ascidian species.
Assuntos
Código de Barras de DNA Taxonômico/métodos , Complexo IV da Cadeia de Transporte de Elétrons/genética , Urocordados/classificação , Animais , DNA Mitocondrial/genética , Índia , Ilhas , Mitocôndrias/genética , Análise de Sequência de DNA , Urocordados/genéticaRESUMO
Ascidians is a crucial group for the studies of deuterostome evolution and the origin of chordates, yet little molecular work has been done to determine the evolutionary relationships and largely unexplored beyond a few species. The phylogenetic analysis are presented for four different species of solitary ascidians, Ascidia virginea, Ascidiella aspersa, Clavelina oblonga and Aplidium fuscum, obtained from Great Nicobar Biosphere reserve (GNBR). Mitochondrial Cytochrome Oxidase subunit 1(COI) gene was amplified and the genetic diversity at the phylogenic level was measured. Bar-coded sequences were extracted with BLAST format from NCBI and the genetic diversity of the submitted sequences were compared with the related ascidian species. Maximum divergences measured among the four species were as follows: Ascidia virginea (96%), Ascidiella aspersa (96%), Clavelina oblonga (94%) and Aplidium fuscum (97%). This is the first report of molecular phylogeny of ascidians from Great Nicobar Biosphere Reserve, Andaman and Nicobar Islands. From this study, we found some stable clades on the evolutionary relationships among these ascidian species that may prompt a reevaluation of some morphological characters.
Assuntos
Genes Mitocondriais , Filogenia , Urocordados/genética , Animais , Complexo IV da Cadeia de Transporte de Elétrons/genética , Análise de Sequência de DNA , Urocordados/metabolismoRESUMO
Aplousobranchia ascidians from two different families were integrated with morphological characteristics and molecular phylogenetic analysis for the first time. The present study employed morphological descriptions (colony structures, tunic, zooids, spicules stigmata and test) and a molecular approach, using a fragment of the mitochondrial cytochrome oxidase I (COI) gene of four Aplousobranchia colonial ascidians Aplidium conicum (98%), Aplidium elegans (98%), Didemnum fulgens (92%) and Trididemnum cyanophorum (94%) from Andaman and Nicobar Islands. Bar-coded sequences were extracted with BLAST format from NCBI and the heritable diversity of the submitted sequences were compared with associated ascidian species. Study revealed that the evolutionary relationship among the ascidian species exhibited the constant clades, which may help for rapid reassessment of morphological characters of the species distributed worldwide.
Assuntos
DNA Mitocondrial/genética , Complexo IV da Cadeia de Transporte de Elétrons/genética , Filogenia , Urocordados/genética , Animais , Evolução Molecular , Variação Genética , Urocordados/anatomia & histologia , Urocordados/classificaçãoRESUMO
BACKGROUND: There is a scarcity of records of morbidity pattern in secondary care centers. Reliable morbidity data will help in proper allocation of human resources. MATERIALS AND METHODS: A retrospective study of inpatient admission records of an urban secondary health center run by family physicians was done between April 2010 and March 2011. RESULTS: Pneumonia and other respiratory illnesses (represented by ICD code J) was the most common diagnosis. This was followed by infectious and viral diseases, circulatory diseases like hypertension, ischemic heart disease and endocrine diseases like non-insulin dependent diabetes mellitus. CONCLUSION: Physicians working in secondary care centres need to be experts in managing respiratory diseases, viral diarrheal illnesses, hypertension, ischemic heart disease and diabetes mellitus and patients with co-morbidities. They also need to be able to manage common obstetrics and neonatal emergencies. As the discipline of family medicine specializes in management of common ailments and multiple co-morbidities with an attitude of patient centeredness, family physicians would be the best managers of such centers. Inclusion of family physicians as specialist in secondary care centers will help in covering the manpower shortage in such centers.