Foi realizado inventário florístico das árvores e arbustos da mata Ribeirão Cachoeira (233,7ha, altitude 650m, coordenadas 46°55'58''W, 22°50'13''S), o segundo maior e mais bem conservado fragmento de floresta estacional semidecidual do município de Campinas, SP. O solo característico é o Podzólico Vermelho Amarelo e o clima é Cwag' de Köppen. As coletas foram feitas durante o período de agosto/1996 a setembro/1997. Foram incluídos apenas indivíduos férteis com perímetro a altura do peito igual ou superior a 9cm. Foram encontradas 175 espécies de 119 gêneros e 49 famílias. As famílias mais ricas foram Myrtaceae (14 espécies), Rutaceae e Fabaceae (13), Caesalpiniaceae (11), Solanaceae (9) e Rubiaceae (8). Algumas espécies foram encontradas pela primeira vez na região: Tachigali multijuga Benth. e Schoepfia brasiliensis A.DC. A floração foi maior entre agosto e outubro. A frutificação foi maior nos meses de agosto a novembro. A maioria das espécies encontradas é zoocórica (58%), as anemocóricas foram 23% e as autocóricas 19%. Compararam-se as relações florísticas desta mata com outros 20 levantamentos do Estado. Os resultados obtidos indicaram a formação de dois grupos distintos. O mais homogêneo deles inclui as florestas do município de Campinas, mostrando que, possivelmente, são remanescentes de uma vegetação originalmente contínua.

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In this study we evaluated floristic composition patterns of communities of climbers within ten inventories carried out in semideciduous forest fragments of southeastern Brazil. One of the inventories is original, being carried out for the present study in Ribeirão Cachoeira forest, Campinas, São Paulo State, Southeastern Brazil. This inventory was then pooled together to other nine climbers' inventories made in other forests of Southeastern Brazil to form a data base, which was examined regarding species richness, similarity, species distribution and climbing methods. The total number of species obtained was 355, belonging to 145 genera and 43 families. The ten most diverse families Bignoniaceae (45 species), Fabaceae (42), Malpighiaceae (36), Asteraceae (31), Apocynaceae (29), Sapindaceae (28), Convolvulaceae (21), Cucurbitaceae (14), Passifloraceae (10), and Euphorbiaceae (8) contributed to 74.4% of the total number of species recorded. The commonest climbing method in the studied sites was main stem or branch twining, accounting for 178 species or 50.1% of the total, the second commonest was tendril climbing (121 species, 34.1%), and the least, scrambling (56 species, 15.8%). We found a high percentage of exclusive species i.e., those occurring in only one forest site, which accounted for 49.3% of the total recorded. The mean similarity among forest sites (30%) may be considered low. The climbing species contribution to the total wood plant richness recorded on the forests sites was very high in some of the sites (up to 52.5%). These results indicated the importance of climber communities to plant diversity for semideciduous forests in Southeastern Brazil, enhancing the regional diversity and the conservation value of these forest remnants.

AimTree crowns determine light interception, carbon and water exchange. Thus, understanding the factors causing tree crown allometry to vary at the tree and stand level matters greatly for the development of future vegetation modelling and for the calibration of remote sensing products. Nevertheless, we know little about large‐scale variation and determinants in tropical tree crown allometry. In this study, we explored the continental variation in scaling exponents of site‐specific crown allometry and assessed their relationships with environmental and stand‐level variables in the tropics.LocationGlobal tropics.Time periodEarly 21st century.Major taxa studiedWoody plants.MethodsUsing a dataset of 87,737 trees distributed among 245 forest and savanna sites across the tropics, we fitted site‐specific allometric relationships between crown dimensions (crown depth, diameter and volume) and stem diameter using power‐law models. Stand‐level and environmental drivers of crown allometric relationships were assessed at pantropical and continental scales.ResultsThe scaling exponents of allometric relationships between stem diameter and crown dimensions were higher in savannas than in forests. We identified that continental crown models were better than pantropical crown models and that continental differences in crown allometric relationships were driven by both stand‐level (wood density) and environmental (precipitation, cation exchange capacity and soil texture) variables for both tropical biomes. For a given diameter, forest trees from Asia and savanna trees from Australia had smaller crown dimensions than trees in Africa and America, with crown volumes for some Asian forest trees being smaller than those of trees in African forests.Main conclusionsOur results provide new insight into geographical variability, with large continental differences in tropical tree crown allometry that were driven by stand‐level and environmental variables. They have implications for the assessment of ecosystem function and for the monitoring of woody biomass by remote sensing techniques in the global tropics.