This study investigated the relationship between leaf production, litterfall, water balance, Leaf Area Index (LAI), and Normalized Difference Vegetation Index (NDVI) in semideciduous forests. The goal was to model this phenomenon to obtain the estimates of this component as an additional compartment of the ecosystem carbon sink. The tests were conducted in eight semideciduous forest fragments. Twenty-four permanent plots were monitored monthly and LAI measurements and weighing of litterfall deposited in nets were conducted for a period of thirteen months. In this period, Landsat 5 and IRS satellite images were obtained and processed for generation of NDVI. The water balance was calculated for each day. The relationship among the variables “leaf dry weight,” “LAI,” “NDVI,” and “water balance” was verified and a regression model was built and evaluated. The deciduous phenomenon can be explained by hydric balance, and LAI and NDVI are ancillary variables. The tendency of the variables in the period of 13 months was explained by quadratic functions. The varied behavior among the monitoring sites helped to know differences in the deposition of leaves. This study showed that only the leaf component of the litterfall of a semideciduous forest in tropical climate can capture 4 to 8 Mg·ha−1·yr−1of CO2and this amount can be estimated using climate, biophysics, and vegetation index variables.

Abstract. This work presents indicators to assess the conservation status of forest patches in fragmented landscapes. However, how can we evaluate the conservation status of forest patches in order to compare it to a hypothetical situation of well-preserved vegetation without human disturbance? It is possible to measure some ecological processes, like nutrient cycling, canopy, edaphic, topographic and hydrological parameters, as well as landscape attributes, and associate them to conservation status. When the attributes of original well-preserved forest are unknown because they are seldom found, it is possible to compare patches by assessing the variability of their attributes. To this end, parameters related to canopy, soil, topography and landscape were analyzed to establish indicators and their integrated analysis was developed to assess the conservation status of forest patches and identify possible causes of shortcomings or obstacles to reach the conservation status. The study area is located in a Semidecidual Forest region, in Brazil. The methodology was developed considering plots distributed in sites within forest patches. The results allowed the identification of patches in different conditions of conservation and provided information of the factors that contribute to this status, in order to help guide and select the most appropriate measures to mitigate degradation and identify forest conservation strategies.

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