DINÂMICA DA COBERTURA DE DOSSEL, TEMPERATURA E UMIDADE DO SOLO EM SISTEMAS AGROFLORESTAIS NO OESTE DO PARÁ

Considering the importance of the forest component in agroforestry systems (SAFs), this study aimed to analyze the dynamics of canopy cover, temperature and soil moisture in three agroforestry systems, which have different arrangements, having in common the production of black pepper (Piper nigrum L.), in Belterra and Mojuí dos Campos, in Pará, inserted in properties of family farmers. Data collection for moisture, soil temperature and canopy cover was performed monthly for nine months (April to December/2017). These measurements were performed at six points in the rows and between the rows of perennial planting in each system. It was concluded that the canopy cover with in the evaluated systems can be considered, in SAFs 1 and 2, as a factor that regulates the amount of light that reaches the system, influencing the soil moisture, both in the row and between the rows. However, soil temperature was the variable that suffered the least interference and that interfered least in the other variables analyzed.Considerando la importância del componente forestalenlos sistemas agroforestales (SAF), este estudiotuvo como objetivo analizar la dinámica de la cobertura del dosel, la temperatura y la humedad del suelo entres sistemas agroforestales, que tienen diferentes arreglos, teniendo em común la producción de pimienta negra (Piper nigrum L.), em Belterra y Mojuí dos Campos, en Pará, insertos em propiedades de agricultores familiares. La recolección de datos de humedad, temperatura del suelo y cobertura del dosel se realizo mensualmente durante nueve meses (abril a diciembre/2017). Estas mediciones se realizaronen seis puntos de lossurcos y entre lossurcos de siembra perene en cada sistema. Se concluyó que la cobertura del dosel dentro de los sistemas evaluados puede ser considerada, em los SAF 1 y 2, como um factor que regulala cantidad de luz que llega al sistema, influyendo em la humedad del suelo, tanto em hilera como entre hileras. Sin embargo, la temperatura del suelo fue la variable que menos interferência sufrió y la que menos interfirió em las demás variables analizadas.Considerando a importância do componente florestal nos sistemas agroflorestais (SAFs) este trabalho objetivou analisar a dinâmica da cobertura de dossel, temperatura e umidade do solo em três sistemas agroflorestais, que dispõem de arranjos diferentes, tendo em comum a produção de pimenta-do-reino (Piper nigrum L.), em Belterra e Mojuí dos Campos, no Pará, inseridos em propriedades de agricultores familiares. A coleta de dados para umidade, temperatura do solo e a cobertura do dossel foi realizada mensalmente durante nove meses (abril a dezembro/2017). Estas medições foram realizadas em seis pontos nas linhas e nas entrelinhas de plantio perene de cada sistema. Concluiu-se que a cobertura de dossel dentro dos sistemas avaliados pode ser considerada, nos SAFs 1 e 2, como um fator que regula a quantidade de luz que chega no sistema, influenciando na umidade do solo, tanto na linha quanto na entrelinha. No entanto, a temperatura do solo foi a variável que menos sofreu interferência e que menos interferiu nas demais variáveis analisadas

PRODUCTION OF SWEET POTATO (Ipomoea batatas (L.) Lam) IN AGROFORESTRY SYSTEM: CASE STUDY OF AN EXPERIMENTAL UNIT IN SANTARÉM, PARÁ, BRAZIL

Agroforestry systems (SAFs) can contribute to the recovery of degraded areas or to the restoration of fragmented landscapes, with emphasis on the diversification of species that can be produced simultaneously. The introduction of short-cycle crops in agroforestry systems, such as sweet potato (Ipomoea batatas (L.) Lam), is an affordable income option, as it demands low production costs and has a relatively short cycle. Sweet potato is a vegetable belonging to the Convolvulaceae family and is indicated for hot climates. In this sense, the present work aimed to evaluate the production of sweet potato in different agroforestry arrangements. The experiment was carried out at the Experimental Farm of the Federal University of Western Pará in Santarém, Pará. Sweet potato was introduced into agroforestry systems, with a completely randomized design and using three plots in each treatment (full sun, African mahogany and teak). The data showed that, under the conditions exposed by the research, sweet potato was not adapted to cultivation in shaded areas, presenting the highest production in full sun conditions, where the intercropping with forest species still does not generate shading for the cultivation.Os sistemas agroflorestais (SAFs) podem contribuir para a recuperação de áreas degradadas ou para a restauração de paisagens fragmentadas, com destaque para a diversificação de espécies que podem ser produzidas simultaneamente. A introdução de culturas de ciclos curtos em sistemas agroflorestais, como a batata-doce (Ipomoea batatas (L.) Lam), é uma opção acessível de renda, pois demanda baixo custo de produção e possui um ciclo relativamente curto. A batata-doce é uma hortaliça pertencente à família Convolvulaceae e é indicada para climas quentes. Nesse sentido, o presente trabalho teve como objetivo avaliar a produção de batata-doce em diferentes arranjos agroflorestais. O experimento foi realizado na Fazenda Experimental da Universidade Federal do Oeste do Pará em Santarém, Pará.  A batata-doce foi introduzida em sistemas agroflorestais, com delineamento inteiramente casualizado e utilizando-se de três parcelas em cada tratamento (pleno sol, mogno africano e teca). Os dados mostraram que, nas condições expostas pela pesquisa, a batata-doce não se mostrou adaptada ao cultivo em áreas sombreadas, apresentando a maior produção nas condições de pleno sol, onde o consórcio com espécies florestais ainda não gera sombreamento ao cultivo

Influence of agroforestry system modalities on maize (Zea mays) yield in an Amazon ecosystem

Corn is among the short-cycle annual species used in agroforestry systems due to its adaptation to intercropping. Thus, this study aimed to evaluate the corn yield, cultivar BIO Z 2365, in two types of agroforestry systems. The experiment was carried out in a forestry agroforestry system in two treatments: mechanized with mineral fertilizer and semi-mechanized with organic fertilizer. The experiment was carried out in a forestry agroforestry system (AFSs), with two treatments, mechanized with mineral fertilizers (MEC) and semi-mechanized with organic fertilizers (SMEC). Each treatment was composed of four crop strips (4 x 24 m) distributed with plants arranged at a distance of 0.50 m between lines, totaling four plots per treatment. A random collection of 20 plants per strip was used, and different variables related to production were evaluated. The productivity was estimated using the EMATER and Reetz methods and by estimating the direct yield. The t-test was adopted to verify the difference between treatments. The mechanized system was superior for all the variables evaluated, obtaining average yield of 41.6 bags ha-1. In the semi-mechanized system, the average yield was 29.2 bags ha-1. The performance of cultivar BIO Z 2365 was better in the mechanized system. However, the results revealed that the cultivation of short-cycle crops, despite technological restrictions in the experimental area, can mean an increase in income for small producers or act in reducing the costs of the implementation and maintenance in agroforestry systems; operating as an agent of economic sustainability

Dendrometric Relationships and Biomass in Commercial Plantations of <i>Dipteryx</i> spp. in the Eastern Amazon

The objective of this study is to characterize and compare the relationships between dendrometric variables in Dipteryx spp. stands in the Western Amazon by fitting linear regression equations for total height (ht) and crown diameter (dc). Six forest stands were evaluated in three municipalities. The variables collected included diameter at 1.3 m height (dbh), ht, and dc. Simple and multiple linear regression equations were fitted to characterize the relationships between ht and dc. The aboveground biomass and carbon stock of the stands were estimated. Most dendrometric variables were positively correlated (97.5%). The general equations presented an R2adj. greater than 0.7, and all coefficients were significant. Equations with non-significant coefficients were common in settlement adjustments (45%). The error for these equations varied between 1.1 and 23.6 m. The trees averaged 22 t ha−1 of aboveground biomass in the stands. There was a variation in carbon sequestration potential among stands, ranging from 5.12 to 88.91 t CO2 ha−1. Single-input equations using dbh as an independent variable are recommended for estimating dc and ht for individual Dipteryx spp. stands. Stands in the Western Amazon play a significant role in carbon sequestration and accumulation. Trees can sequester an average of 4.8 tons of CO2 per year