Temporal variation of Nitella furcata subsp. mucronata var. mucronata f. oligospira (Charophyceae) in the Ninféias pond, São Paulo State, southeast Brazil

Abstract

Temporal and spatial variation of Nitella furcata (Roxburgh ex Bruzelius) C. Agardh emend. R.D. Wood subsp. mucronata (A. Braun) R.D. Wood var. mucronata f. oligospira (A. Braun) R.D. Wood were studied at the Ninféias pond (23°38'18.9"S, 46°37'16.3"W), a tropical, shallow, mesotrophic reservoir located in the Parque Estadual das Fontes do Ipiranga Biological Reserve, Municipality of São Paulo, southeast Brazil. Water samples were collected monthly from October/1996 to October/1997 for turbidity, electric conductivity, pH, alkalinity, dissolved oxygen, nutrients, biomass, and algal phenology analysis. Spatial distribution pattern of algal biomass showed that all four sampling stations were similar among themselves during the whole study period. Regarding the temporal variation, greatest algal total biomass values (98.35-266.06 g.m-2) were measured during the rainy period whereas the smallest ones (48.86-170.56 g.m-2) were detected during the dry period. Algal population density peaked at all four sampling stations from October/1996 to April/1997 (rainy period) when the greatest values of air and water temperature, precipitation, solar radiation, turbidity, total nitrogen, and ammonium were measured allowing favorable conditions for the algal growth. Period from May/1997 (late fall) to October/1997 (early spring) was favorable to the development of reproductive structures (nucules and globules) with consequent decrease of algal biomass and population density, clearly suggesting the greatest energy allocation towards the development of sexual reproductive structures. This fact was confirmed by the canonic correspondence analysis that indicated strong correlation between nucules length and width, number of nucules per plant, and oospores length and width with the low values of pH and high ones of dissolved inorganic matter detected during the dry period. Consequently, environmental factors such as increasing of water temperature and nutrients availability at the Ninféias pond acted decisively towards growth and accumulation of algal biomass.

Biomass and chemical composition of Nitella furcata subsp. mucronata var. mucronata f. oligospira (A. Braun) R. D. Wood (Chlorophyta, Characeae) in the littoral region of Ninféias Pond, São Paulo, Southeast Brazil

“…Bueno & Bicudo (2006) summarizes the environmental variables measured for each sampling station at the Ninféias pond and their respective analytic methods. Table 1.…”

“…Palma-Silva et al (2004) approached the charophytes as a nutrient and energy reservoir in the same lagoon above, under anthropic impact. Finally, Bueno & Bicudo (2006) …”

“…Study on Characeae of lotic environments in Brazil is restricted to those of Vieira and ; and on material from lentic systems to those of Palma-Silva et al (2002a, 2002b, 2004 and Bueno & Bicudo (2006). are taxonomic papers and dealt, respectively, with the floristic survey of genera Nitella and Chara in lotic systems of the southeastern region of the state of São Paulo.…”

Levantamento florístico das Characeae (Chlorophyta) de Mato Grosso e Mato Grosso do Sul, Brasil: Chara

“…Para ambiente lênticos são Carneiro et al (1994), Palma-Silva (1998), Palma-Silva et al (2000, 2002a, 2002b e Bueno & Bicudo (2006, 2008. Os estudos do tipo taxonômico são os de Bicudo (1968ade Bicudo ( , 1968bde Bicudo ( , 1969de Bicudo ( , 1972de Bicudo ( , 1974de Bicudo ( , 1976de Bicudo ( , 1977de Bicudo ( , 1979, Astorino (1983), Bueno et al (1996), Bueno & Bicudo (1997, Picelli-Vicentim et al (2004) e Prado & Baptista (2005).…”