Germinación de semillas después del fuego: Un estudio con una planta que habita áreas no propensas al fuego

Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)

Latitudinal variation in population structure and reproductive pattern of the endemic south american shrimp Artemesia longinaris (Decapoda : Penaeoidea)

Population Structure and reproductive Maturity of females were investigated in the shrimp Artemesia longinaris Bate, 1888 from coastal waters of northern São Paulo State (Brazil. 23 degrees S) and Mar del Plata (Argentina, 38 degrees S) from June 2001 to May 2002. Monthly collections were taken by, commercial shrimp fishing boats equipped with bottom trawl nets. Population parameters from size frequency distributions and size (carapace length = CL) of female reproductive maturity were analyzed and compared front the two sampling areas. Latitudinal trends in reproductive parameters of A. longinaris were shown in overall body size and size of reproductive maturity, both of which were smaller in females from the tropical location than those front the cold-temperate sampling area. Largest females (> 30 turn CL) were collected in Argentina, while Brazilian specimens reached maximum size at 27 nun CL. The smallest Size of female sexual maturity was estimated at 13.6 nun CL in Brazilian samples compared to 22.1 mm CL calculated for those from Argentina. Populations from both regions exhibited a bimodal size distribution in the spring, with the peak at small body size probably corresponding to recent recruits and the peak at larger body, size to reproductive females or shrimps migrating in from deeper waters or other latitudinal regions. In late spring and summer. an intrusion of the cold South Atlantic Coastal Water mass was observed which lowered water temperature and stimulated plankton production. The primary food source for the larvae of a typically cold-temperate species such as A. longinaris. The trend of increasing body size and delay of sexual maturity with increasing latitude appears to be correlated with the decreasing water temperature and increasing plankton productivity at higher latitudes.

Capacidad de uso de la tierra en la cuenca de la Corriente del Lobo, Itatinga, São Paulo, Brasil

The objective of the research was to define the classes of use capacity of 2403.25 ha in the basin of the Corriente del Lobo - Itatinga (SP), (22°03'56" to 22°59'12" of latitude S and 48°38'47" to 48°41'25" of longitude W Gr.). The soil use capacity was obtained by using the SIG IDRISI 32 crossing the documents of steepness and soils and the document of judgment of classes of soil use capacity and of the utilitarian rising of the physical milieu. The classes and subclasses areas of use capacity presented the following values: IIIa - 68.60 ha (2.85%), IIIe,s - 1919.15 ha (79.86%); IIIe - 210.60 ha (8.76%); IVe - 3.38ha (0.14%); IVe,s - 157.42 ha (6.55%) and VIe,s - 44.10 ha (1.84%). The lands of the basin were distributed in three classes (III, IV and VI) and six subclasses but the biggest extension (79.9%) belonged to the subclass IIIe,s. The modules of the IDRISI allowed to discriminate, mapping and to quantify quickly the soil use capacity of the areas of classes and subclasses in the basin.