Abstract The aim of this study was to evaluate the precision and efficiency of the forest inventory method from using Terrestrial Laser Scanner (TLS) to determine dendrometric variables in teak plantations (Tectona grandis Linn. F.). Circular sampling plots of 500 m2 were established in three teak plantations located in the Coastal region of Ecuador. Traditional forest inventory (TFI) and TLS methods were used to determine several dendrometric variables (normal diameter, total height, and crown radius), also recording the work time necessary to complement the inventory of each plot. The estimates of the dasometric indices for each inventory method and the relative efficiency of TLS with respect to IFT were contrasted using statistical inference tests. The statistical tests did not detect significant differences between the two inventory methods in relation to both the measured dasometric variables and the working times recorded in each plot. The relative efficiency values showed some superiority of TLS method over TFI. Forest inventories of teak plantations based on TLS method is sufficiently accurate for estimating dasometric variables, being more efficient than traditional inventory.

Resumen El objetivo de la investigación fue evaluar la precisión y eficiencia del método de inventario forestal usando el escáner láser terrestre para la determinación de variables dendrométricas en plantaciones de teca (Tectona grandis Linn. F.) . Se establecieron sitios de muestreo circulares de 500 m2 en plantaciones de teca de tres predios de la región Costa de Ecuador donde se usaron las metodologías de inventario forestal tradicional y del escáner láser terrestre, registrando las variables dendrométricas (diámetro normal, altura total y radio de copa) y el tiempo de trabajo necesario para complementar el inventario de cada parcela. Las estimaciones de los índices dasométricos para cada método de inventario y la eficiencia relativa del método del escáner láser terrestre con respecto al inventario forestal tradicional fueron contrastadas mediante pruebas de inferencia estadística. La prueba de contrastes estadísticos aplicada no detectó diferencias significativas entre los dos métodos de inventario en relación tanto con las variables dasométricas medidas como con los tiempos de trabajo registrados en cada parcela. Los valores de eficiencia relativa evidenciaron cierta superioridad del inventario realizado con el escáner láser terrestre sobre el realizado con el inventario forestal tradicional. El presente estudio permite concluir que el método del escáner láser terrestre para la elaboración de inventarios forestales en plantaciones de teca es preciso para la estimación de variables dasométricas, siendo más eficiente que el de inventario tradicional.

RESUMO O objetivo desse estudo foi avaliar e comparar as normas DRIS para o cultivo de pimentão vermelho com e sem enxerto, cultivado em condicões semi-áridas. As normas DRIS foram obtidas com 84 amostras de folhas recentemente amadurecidas, considerando o período de desenvolvimento da cultura. O delineamento experimental foi por blocos completamente ao acaso, e os valores obtidos de cada planta e cada variável foram considerados como réplica independente. Dos resultados analíticos de N, P, K, Ca, Mg, Fe, Cu, Zn e Mn foram computados trinta e duas normas Dris e seu coeficiente de variação (CV). As quantidades ou proporções de P/N e K/N em plantas de pimentão com e sem enxerto mostraran baixos CV e, por tanto, de acordo com as normas DRIS, têm função fundamental no desenvolvimento da cultura, devido ao fato que uma pequena modificação pode ocasionar variação significativa no balanço nutricional da planta. Concluindo, as normas DRIS são sensíveis ao enxerto em plantas. Este trabalho pode significar melhoria significativa na diagnose nutricional do pimentão vermelho, com e sem enxerto, em condições semiáridas em casa de vegetação sob sombra.

ABSTRACT The objective of this study was to compute and compare DRIS norms for grafted and non-grafted red bell pepper crops grown in semi arid climate conditions. DRIS norms were computed with 84 samples of first young mature leaves collected during developed stage. The experiment had a completely randomized block design, and the values obtained for each plant and each variable were considered as independent replicates. Thirty-two DRIS norms nutrient ratios and coefficients of variation (CV) were computed from N, P, K, Ca, Mg, Fe, Cu, Zn and Mn analytical results. The ratios P/N and K/N in grafted and non-grafted pepper plants, showed low CV and therefore may play a fundamental role in crop production according with the DRIS norms calculated, since as light modification in the nutrient concentration led to a significant change in the nutritional balance. In conclusion, DRIS norms are sensitive for grafted and non-grafted plants. This work may signify an improvement in the nutritional diagnosis of grafted and non-grafted red bell pepper in semi arid climate conditions under a shaded greenhouse.