Monitoramento da precipitação efetiva em diferentes povoamentos florestais: estudo de caso na Floresta Nacional de Ipanema, Iperó-SP

Abstract

The water, renewable resource, but finite, has been studied in many areas of knowledge, especially with regard to their availability on the surface. Other studies, however, are developed to identify how and how much is their participation in various stages of the hydrology cycle. Researchs that relates rain with the rain forest systems are examples of this. This paper aims to present the importance of determining the effective rainfall, and to study the influence of forest vegetation in the hydrological cycle in watersheds, as well as the present study that is being developed in the Floresta Nacional de Ipanema, in Iperó-SP. These studies collect information on understanding the distribution of water on vegetation in order to generate forms of management are technically feasible, facilitating the important decisions for the integrated use of watershed.

PARTITIONING OF RAINFALL IN EXPERIMENTAL PLANTATIONS OF Eucalyptus urophylla AND Pinus elliottii

“…In general, gross rainfall was responsible for approximately 70% of the stemflow variation in both species, a similar result to those found for E. cloeziana (71%) and P. caribaea (69%) by Shinzato et al (2011). The lower influence of gross rainfall on stemflow variation than on throughfall was reported in studies of planted forests and natural forests (LIMA, 1976;MOURA et al, 2012).…”

“…He also pointed out that to have stemflow in the pine plantation, a greater amount of rainfall was needed than that for eucalyptus. For E. cloeziana and P. caribaea, Shinzato et al (2011) verified the occurrence of stemflow from rainfalls of 6.6 mm and 8.2 mm, respectively. The linear regressions of the gross rainfall versus the throughfall were highly significant.…”

Net Precipitation in a Semideciduous Forest Fragment in Viçosa City, Mg

“…In order for stemflow to occur, canopy must first be saturated, i.e., the maximum water retention capacity must be reached. After the canopy is saturated, as the rain continues to fall, the process of stemflow takes place (SHINZATO et al, 2011).…”

THE INFLUENCE OF THE NUMBER OF LEAVES IN THE MACAÚBA PALM Acrocomia aculeata (Jacq.) Lodd. ex Mart. ON THE CORRELATION BETWEEN STEMFLOW AND GROSS PRECIPITATION

“…From the four regression equations obtained, we estimated that stemflow in macaúba occurs after gross precipitation equal to or greater than: 2.62 mm in plants with 10 leaves, 2.24 mm in plants with 13 leaves, 1.91 Shinzato et al (2011), stemflow only occurs after a gross precipitation equal to or greater than 11.0, 6.6, and 8.2 mm in a seasonal semideciduous forest, in Eucalyptus cloeziana, and in Pinus sp., respectively. Comparing our estimations with the values reported by these authors, we could conclude that the macaúba palm has a great capacity to intercept and direct rainfall waters to its stipe, thus allowing the occurrence of stemflow even with light rainfall events.…”

“…In order for stemflow to occur, the first event needed is crown saturation, i.e., the tree crown must reach its maximum capacity of water retention. After that, the stemflow process initiates (SHINZATO et al, 2011). According to Oliveira et al (2011), despite being constantly neglected by several authors, as it represents a small portion of the annual hydric balance, stemflow has a great importance in the hydrological cycle, as it represents a volume of water that reaches the soil with low velocity, thus favoring infiltration and recharging water tables.…”