Litter fall consists of all organic material deposited on the forest floor, being of extremely important for the structure and maintenance of the ecosystem through nutrient cycling. This study aimed to evaluate the production and decomposition of litter fall in a secondary Atlantic forest fragment of secondary Atlantic Forest, at the Guarapiranga Ecological Park, in São Paulo, SP. The litter samples were taken monthly from May 2012 to May 2013. To assess the contribution of litter fall forty collectors were installed randomly within an area of 0.5 ha. The collected material was sent to the laboratory to be dried at 65 °C for 72 hours, being subsequently separated into fractions of leaves, twigs, reproductive parts and miscellaneous, and weighed to obtain the dry biomass. Litterbags were placed and tied close to the collectors to estimate the decomposition rate in order to evaluate the loss of dry biomass at 30, 60, 90, 120 and 150 days. After collection, the material was sent to the laboratory to be dried and weighed again. Total litter fall throughout the year reached 5.7 Mg.ha-1.yr-1 and the major amount of the material was collected from September till March. Leaves had the major contribution for total litter fall (72%), followed by twigs (14%), reproductive parts (11%) and miscellaneous (3%). Reproductive parts had a peak during the wet season. Positive correlation was observed between total litter and precipitation, temperature and radiation (r = 0.66, p<0.05; r = 0.76, p<0.05; r = 0.58, p<0.05, respectively). The multiple regression showed that precipitation and radiation contributed significantly to litter fall production. Decomposition rate was in the interval expected for secondary tropical forest and was correlated to rainfall. It was concluded that this fragment of secondary forest showed a seasonality effect driven mainly by precipitation and radiation, both important components of foliage renewal for the plant community and that decomposition was in an intermediate rate.

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RESUMO O cultivo de plantas tem uma relação com o homem desde as primeiras organizações humanas. O uso de plantas em quintais é uma tradição que tem passado de geração a geração em determinadas localidades. O objetivo deste trabalho foi levantar a ocorrência de quintais domésticos em diferentes cidades de três estados brasileiros, além de conhecer uso das plantas cultivadas

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Environmental issues in urban areas have been increasingly discussed in the construction of smart and sustainable cities. Thus, public green spaces have become the focus of studies for bringing several contributions to the urban environment, as well as provide many ecosystem services. However, it is important to know how users of these green spaces perceive the environment around them, especially in the context of creating new parks in areas with intense human settlements. The aim of this study was to investigate the ecological knowledge of residents surrounding an urban green area in the east zone of São Paulo city, which became municipal park after the end of this study. The Municipal Park Jardim da Conquista (PMJC) is located in an area considered one of the largest human settlements in Brazil and the world. 675 interviews were carried out with people living around the urban park in 2013. The profile of the supposed goers varies between 20 and 30 years, belonging predominantly to C economic class and also with sporadic profile of visiting the park. The interviewed people related these green spaces with leisure and biodiversity conservation. In addition, residents attribute part of the care and preservation of the park to themselves. This work highlights the user profile of a new park in the city of São Paulo, as well as their knowledge of some ecological aspects of an urban park.