Fertilidade do solo e crescimento de espécies arbóreas em uma agrofloresta em Jupiá, região oeste de Santa Catarina

Abstract

Agroforestry systems are sustainable production alternatives for the production of food, wood and firewood. Besides to the benefits to natural resources provided by the use of agricultural and forest species in the same area unit. The objective of this work was to evaluate the growth of tree species and to relate them to the attributes of soil fertility in an agroforestry in the first years of development. The agroforestry was implanted in November of 2011 in Jupiá, West region of Santa Catarina, Brazil. In an area of 3,000 m2, where tree species and fruit species were combined. In total, 295 seedlings of 21 species were implanted in 10 lines, with 3 x 3 m spacing. Morphometric data were collected from all surviving trees once a year, from April 2013 to April 2017. In 2017, the area was divided into quadrants and chemical soil collection and analysis was performed at 15 sampling points in each quadrant. We verify the heterogeneity of distribution of soil fertility attributes and their influence on the perceived heterogeneous growth of trees. The data were subjected to analysis of variance and Scott-Knott test. Principal component analysis (PCA) was performed to relate tree growth to soil attributes. Geostatistics was used, using the kriging method, to analyze the distribution of spatial variability of soil chemical attributes in each quadrant. Soil sites with higher levels of phosphorus and potassium generated greater growth of tree species, when eucalyptus growth data was excluded. These points coincided mainly with the quadrants Q3 and Q4 of this agroforestry, which refers to the previous use of this area, since in these quadrants there was a greater deposit of bovine manure in relation to the other two quadrants. Therefore, it is recommended that agroforestry with these tested tree species, be implanted in areas with high fertility or that the soil be corrected and fertilized before implantation, after multiple soil sampling, in order to homogenize and enhance the fastest growth of the trees.