Recife, at Ipojuca (Pernambuco, Brazil), and stands out on the state coast for showing two of the most productive ecosystems: reef and estuary. The objective of this study was to diagnose the current status of these ecosystems considering phytoplankton biomass (chlorophyll a) and productivity (C 14 ), and some environmental variables such as depth, water transparency, temperature, salinity, dissolved oxygen, nutrient salts, pH and particulate suspended material. Samples were collected from the surface at six sites during high and low daytime spring tides on three months during each season, rainy and dry. Salinity varied from 1 to 37, oxygen saturation from 56.78 to 173.82%, nitrite and phosphate were less than 1µmol.L -1 , nitrate was <3.5µmol.L -1 and silicate varied from 11.71 to 92.26µmol.L -1 ; biomass ranged from 1.11 to 18.72mg.m -3 and productivity from 4.62 to 75.27mgC.m -3 .h -1 . According to Principal Components Analysis (PCA) results, there was high positive correlation between tides, depth, transparency, salinity and dissolved O 2 , and inverse correlation to silicate, chlorophyll a, productivity and assimilation rate; also, the pluviometry was directly correlated to nitrite, nitrate and phosphate and inversely to temperature. The environment showed to be homogeneous, that is, without thermal and saline stratification, varying from oligohaline to euhaline and predominantly supersaturated throughout the study, typical of unpolluted areas, and the trophic rate varied from oligotrophic to eutrophic. The studied coastal area was characterized by clear and warm waters with no influence of domestic or industrial effluents.Keywords: chlorophyll a, hydrology, estuary, reefs, Maracaípe. INTRODUÇÃOAs áreas costeiras são as mais ricas dos oceanos e respondem por mais da metade da sua produtividade sendo responsável por quase o total da pesca mundial. Ao longo dos litorais, sais nutrientes são retirados do continente, ventos de superfície e correntes marítimas dragam sedimentos ricos nestes sais, e a luz solar favorece o crescimento de organismos fotossintetizantes (Corson, 2002).Em conseqüência da entrada constante dos nutrientes de origem continental, as águas costeiras tendem a não apresentar exaustão total destes sais, mesmo nos trópicos (Pereira & Soares-Gomes, 2002). Elevadas taxas no ambiente costeiro freqüentemente induzem o crescimento da biomassa fitoplanctônica, aumentando assim, a quantidade de matéria orgânica e resultando numa eutrofização (Nixon, 1995;Smith et al., 1999).As algas planctônicas possuem um grande significado ecológico, por constituírem o inicio da teia trófica, e também por responderem rapidamente aos impactos ambientais, sendo desta forma excelentes indicadores da qualidade da água (Eskinazi-Leça et al., 2002). A ação dos fatores ambientais reflete diretamente na estrutura da comunidade, condicionando o estabelecimento da mesma, que se encontra adaptada às oscilações destas variáveis (Silva-Cunha, 2001).Os ecossistemas aquáticos vêm sendo gradativamente destruídos pelo consta...
scite is a Brooklyn-based organization that helps researchers better discover and understand research articles through Smart Citations–citations that display the context of the citation and describe whether the article provides supporting or contrasting evidence. scite is used by students and researchers from around the world and is funded in part by the National Science Foundation and the National Institute on Drug Abuse of the National Institutes of Health.
hi@scite.ai
10624 S. Eastern Ave., Ste. A-614
Henderson, NV 89052, USA
Copyright © 2024 scite LLC. All rights reserved.
Made with 💙 for researchers
Part of the Research Solutions Family.