Sistema Regional de Información
en línea para Revistas Científicas de América Latina,
el Caribe, España y Portugal

The present study was carried out with the purpose of evaluating the bioinsecticidal effect of Tagetes erecta leaves on larvae of Zadiprion vallicola. Water, acetone and ethanol extracts of T. erecta leaves were extracted by maceration. The extracts were applied in concentrations of 250 mg/L, 500 mg/L, 750 and 1000 mg/L and distilled water used as control. Mortalities were corrected in proportion and an analysis of variance was performed. In addition, the LC50 was calculated for the various extracts obtained. There were differences in mortality in concentrations (F = 171.4, p < 0.001), between solvents (F = 1060, p < 0.001) and in their interactions (F = 7.3, p < 0.001). For the control group the mortality was null, due to the extracts; the greater mortalities were presented in applications greater than 500 mg/L. As concentrations increased, mortality marked a tendency to stabilize. Acetone and ethanolic extracts, with mortalities of 0.81 and 0.96, were highly effective compared to water extracts with a mortality of 0.64. The ethanol extracts produced an LC50 of 63.1 mg/L and the acetonic extracts of 64.5 mg/L, low concentrations compared to that produced by the water extracts of 398.1 mg/L. The effects of these extracts on the mortality of Z. vallicola are similar to those reported for the entomopathogenic fungus Metarhizium anisopliae, and therefore represent a valuable alternative for its control, especially in the case of ethanol extracts.

The use of renewable materials as a source of nutrients, besides being a solution of interest for waste disposal, may also be an effective way to reduce the high costs of inputs needed for the production of forestry seedlings. The purpose of this study was to evaluate the growth of Anadenanthera colubrina (Vell. Brenan) (angico branco) cultivated in organic substrates. A randomized block design was adopted and the treatments were distributed in a 3 × 5 factorial scheme, with three organic residues: decomposed burity (moriche palm) stem, carnaúba straw and organic compost mixed with the soil in four percentages: 20%, 40%, 60% and 80% of the composition of substrate and a control treatment with soil only, without incorporating the organic residue, with six repetitions. Ninety days after emergence, the seedlings were collected to determine the growth parameters: stem diameter (SD), height (H), of the following indexes: H/D, leaf number (LN), total chlorophyll (T), leaf area (LA), dry mass of the aerial part (DMAP), dry mass of roots (DMR), total dry mass (TDM) H/DMAP: DMAP/DMR, and Dickson Quality Index (DQI). The treatments that contained 60% and 80% of organic compost presented the best responses. It is concluded that the production of angico branco seedlings cultivated with substrate with the addition of 80:20 (organic compost: soil) presented the best results and was technically feasible according to the characteristics and indexes analyzed.

Plant roots help to avoid soil loss since they form meshes that retain it, especially in sandy soils with low cohesion. However, technical documentation over the execution of tests to characterize roots is scarce; therefore, a detailed approach is required in order to perform reliable studies. The objectives of this work are to document and characterize the mechanical properties of the roots of two tropical species through tension and bending tests. To this end, special devices were designed to hold roots of Jatropha curcas L. and Ricinus communis L. extracted from sandy soils. The roots were subjected to tension and bending tests and their corresponding modulus of Young were estimated, as the maximum bending stresses. The Young tension moduli varied between 6.27 MPa to 334 MPa for Ricinus and 4.56 MPa to 271 MPa for Jatropha, with diameters between 0.5 mm and 6.8 mm for both species; during the bending tests, the roots never reached the breaking point, but they registered maximum stress values of 21 MPa and 28 MPa for Ricinus and Jatropha respectively. It is concluded that roots of Jatropha and Ricinus have low moduli of elasticity values, similar to other herbs and trees roots, with a very high flexibility, comparable to low density polyethylene.

This study aims to estimate the profitability and to evaluate the economic risks of REDD + projects in the Brazilian Amazon. The data were obtained through interviews and questionnaires to the proponents of the private REDD + projects of Amazonia. The economic risk was calculated using sensitivity analysis of the key project variables and the probability of project profitability through the Monte Carlo Simulation Method. The results indicate that the variable cost was responsible for 80% of the total costs. Fixed costs accounted for 20% of total costs. The result of the cash flow risk analysis concluded that REDD + projects in the Brazilian Amazon are viable, Internal Rate of Return of 11.49% a.a. was greater than the 10% a.a. Minimum Attractiveness Rate. The point at which the project computes a positive NPV is the price of BRL 18.6. Projects that sold VCUs at a price lower than BRL 18.6 may be financially unfeasible. The Monte Carlo simulation showed that the probability of obtaining a TIR of 10% a.a. or more is 51.53% a.a. It is concluded that REDD + projects in the Amazon have a positive return probability approaching 50%, but this return is not as attractive.

This essay reflects on the past, present, and potential future of global governance, its historical practices and principles, the interests it has served, and who/what it has included/excluded or marginalized. It initially explores ontological, conceptual, and normative issues, and how these have been historically connected to the dynamics of world orders, patterns of global governance, and global capitalism. It reflects on developments from the eleventh century up to World War II and critically appraises presently dominant principles and practices of global governance—in order to highlight key questions concerning the future. The essay asks whether current practices are in contradiction to the material and human interests and indeed the very survival of humankind and the integrity of the planet, its biosphere, and its life-forms. It concludes by identifying some forms of political agency that might help reshape governance towards more equitable, socially just and sustainable planetary governance.