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Introduction- The ecotoxicological tests with terrestrial organisms are recent as compared to aquatic organisms (ROMBKE and KNACKER, 2003); however, new studies shall be encouraged according to their importance in the complex food chain (EMBRAPA, 2004). Thus, forest soils were assessed by means of ecotoxicological tests with plants and earthworms and compared to laboratory controls.

Methodology- Samples of forest soils from four different areas (A, B, C and D) were collected in the municipalities of Domingos Martins and Venda Nova do Imigrante, State of Espírito Santo, at a depth of 0 - 5 cm. The samples were submitted to ecotoxicological tests withLactuca sativa, Zea mays and Eisenia fetida(ABNT, 2007; ABNT, 2009). The soil used as laboratory control for tests with plants was collected in the region of Domingos Martins, and an artificial soil was used for tests with earthworms (ABNT, 2007). After exposing the organisms to the soils, the plant biomass (15 days) and earthworm biomass (14 days) were assessed. Feasibility of the organisms used was checked through sensitivity tests with boric acid. Chemical analyses were also held with the soil samples. The data were submitted to normalcy, followed by ANOVA and subsequently the Tukey test ([CFP1] = 10%).

Results and Discussion- With regard toL. sativa,the biomass produced in soil for laboratory control (0.0466 g/kg) was significantly lower than with soils from the forest A (0.1756 g/kg), forest B (0.3144 g/kg), forest C (0.2326 g/kg), and forest D (0.1282 g/kg). With regard toZ. mays, a similar result was observed, the laboratory control evidenced biomass below (2.6190 g/kg) that with soils from the forest A (5.0448 g/kg), forest B (4.7567 g/kg), forest C (4.3153 g/kg), and forest D (4.3022 g/kg). The greater biomasses for L. sativa were found in area B, and the same occurred forZ. maysin area A. All of the forest soils presented greater concentrations of P, K, Ca, Mg and N as compared to laboratory controls, and that may have been responsible for the higher biomass of the plants, considering these elements are directly related to their growth (SEVERINO et al., 2006). The results of tests with earthworms indicated an opposite trend, as in the artificial control (1.4876 g/kg) the biomass was greater than the one found in soils from the forest A (0.0191 g/kg), B (-0.6091 g/kg), C (-0.8182 g/kg), and D (0.3864g/kg). Moreover, it was found that earthworms lost weight in two forest soils. Light organic matter (MOL) in the artificial soils was greater as compared to soils from forest A (1.988 g/kg), forest B (1.918 g/kg), forest C (0.715 g/kg). and forest D (3.407 g/kg), which explains the result presented and ratified by Sivakumar and Subbhuraam (2005).

Conclusion- The forest soil proved to be satisfactory for use in ecotoxicological tests, as the organisms became adapted and developed during the tests. Nonetheless, additional studies shall be developed to assess any interventions required, in order to compare their results to the environmental samples.