Efeito do tipo de adubação no crescimento inicial de sete espécies arbóreas

Abstract

The degradation of forests in tropical regions caused by anthropic actions, mainly due to agricultural activities, has resulted in impacts such as the loss of ecosystem functions and services. This degradation results in changes in soil chemical and physical properties, and biological communities. Forest restoration aims to minimize these impacts, through the reintroduction of native tree species. Understanding the mechanisms involved between the performance of different plant species and the state of soil degradation can lead to more efficient forest restoration practices. This study experimentally evaluated the effects of soil nutrient and organic matter availability on the growth of seven native tree species: Guazuma ulmifolia Lam., Pterogyne nitens Tul., Copaifera langsdorffii Desf., Peltophorum dubium (Spreng.) Raub., Hymenaea courbaril L., Cariniana estrellensis (Raddi) Kuntze and Terminalia argentea Mart.. We monitored plant initial growth and the changes in soil nutrient availability over time in seedling cultivations under three types of fertilization, one chemical (addition of NPK), and two organic additions, using restaurant waste and cattle manure. The plants were also cultivated in soil without any type of fertilization, which was used as a control. The experiment was conducted in a nursery with irrigation twice a day and monitored for approximately 30 weeks from the germination of each species. Soil chemical analyses were carried out monthly for each of the three treatments, plus control, to quantify the levels of OM, K, P, pH, N, V% (base saturation) and m% (aluminum saturation). A Principal Component Analysis of the chemical parameters showed that the soils were organic fertilizer was added were related to the first axis, which was correlated with OM, P, pH, N and V%, whereas the control was close to m%. The chemical treatments, on the other hand, were related with the second axis, which was correlated with K concentrations. There were no significant differences among organic fertilization, cattle manure and restaurant waste, but these treatments differed from chemical fertilization and control. Plants grown in soil that received organic fertilization had the highest growth, with cattle manure being responsible for the largest average individual size in three of the seven species. Individuals grown in control soils presented the lowest growth. Only three species germinated in the treatment that received chemical fertilization, and they reached intermediate sizes when compared to soils with organic fertilizers and controls.