SEWAGE SLUDGE COMPOST ASSOCIATED TO FREQUENCY OF IRRIGATION FOR Peltophorum dubium (Sprengel) Taubert SEEDLINGS PRODUCTION

Inappropriate disposal of sewage sludge has become an environmental problem. In some Brazilian states, such as São Paulo, in natura sewage sludge use is practically prohibited due to restrictive requirements by CONAMA Resolution No. 375/2006. Therefore, a very promising alternative to reuse this residue is to compost it with other materials and use it as a substrate in the production of seedlings. The objective of this study was to evaluate the development of the seedlings of Peltophorum dubium in compost with sewage sludge, to determine which frequency of irrigation would be more adequate according to the physical characteristics of each substrate, and if this would influence the morphological and nutritional variables of the seedlings. Two composts were produced: sewage sludge composted with sugarcane bagasse and sewage sludge composted with eucalyptus bark, both in 1: 1 proportion. Commercial substrate was used for control. This study was completely randomized in a 3x3 factorial design, which three substrates and three frequencies of irrigation were tested: two, three and four times per day. The evaluated parameters were: plant height, stem diameter ratio, shoot / root ratio, leaf dry mass, root dry mass, total dry mass, green color index, Dickson quality index (IQD), water loss through leaching and substrate water retain capacity. The best results were observed in the seedlings produced in sewage sludge compound with eucalyptus bark submitted to the frequencies of two or three times a day

Diversidad florística y estructura del bosque nublado del Río Numbala, Zamora-Chinchipe, Ecuador: El “bosque gigante” de Podocarpaceae adyacente al Parque Nacional Podocarpus

A forest inventory in a one-hectare permanent plot was conducted in the Numbala Reserve, a protected area of 1013 hectares, located in Palanda canton, Zamora- Chinchipe province, Ecuador, bordering the Podocarpus National Park, at 2100 m, 4°24’19”S, 79°03’36”W. The site is owned and administered by Nature and Culture International, a non-governmental conservation organization. All trees with DBH (diameter at breast height) ≥ 5 cm were inventoried in the plot. A total of 1091 trees and 171 species were recorded, with a basal area of 47.73 m²/ha and a total timber volume of 652 m3/ha. The dominant species of the forest by their diameters and heights are gymnosperms, two species of Podocarpaceae: Retrophyllum rospigliosii and Prumnopitys harmsiana, which together constitute 59.7% of the basal area and 79.6% of the total wood volume inventoried in the plot. A total of 35 trees of these two species have diameters greater than 70 cm and up to 47 m in height in the plot. Despite the dominance of the two species of gymnosperms, the floristic diversity is relatively high with 171 species of trees recorded in the plot, including numerous species of Rubiaceae, Lauraceae, Meliaceae, Myrtaceae and Melastomataceae. The values of basal area and timber volume, and the number of large trees greater than 70 cm DBH, are very high compared to other neotropical forests. There is bibliographic evidence from past decades of large stands dominated by Podocarpaceae, particularly Retrophyllum rospigliosii, in other Andean countries, but almost all have been cleared for timber extraction, and the Numbala forest is one of the last remnants of these "giant forests" of Podocarpaceae in the tropical Andes.Se realizó un inventario de bosque en una parcela permanente de una hectárea en la Reserva Numbala, un área protegida de 1013 hectáreas, propiedad de la fundación Naturelza y Cultura Internacional (NCI), ubicada en el cantón Palanda, Zamora- Chinchipe, Ecuador, colindante con el Parque Nacional Podocarpus, a 2100 m.s.n.m., 4°24’19”S, 79°03’36”W. Se realizó el inventario de los árboles con DAP (diámetro a la altura de pecho) ≥ 5 cm. Se registró un total de 1091 árboles y 171 especies, con un área basal de 47,73 m²/ha y un volumen total de madera de 652 m3/ha. Las especies dominantes del bosque por sus diámetros y alturas son Gimnospermas, dos especies de Podocarpaceae: Retrophyllum rospigliosii y Prumnopitys harmsiana que representan 59,7% del área basal y 79,6% del volumen total del bosque en la parcela inventariada, que incluye 35 árboles de estas dos especies con diámetros mayores a 70 cm y hasta 47 m de altura. No obstante la dominancia de las dos especies de Gimnospermas, la diversidad florística es relativamente alta con 171 especies de árboles registrados, incluyendo diversas especies de Rubiaceae, Lauraceae, Meliaceae, Myrtaceae y Melastomataceae. Los valores de área basal y volumen de madera, y la cantidad de árboles grandes mayores a 70 cm DAP, son muy altos en comparación con otros bosques neotropicales. Hay evidencia bibliográfica de la existencia en el pasado de rodales grandes dominados por Podocarpaceae, particularmente de Retrophyllum rospigliosii, en otros países andinos, pero casi todos han sido talados por la extracción de madera, y el bosque de Numbala es uno de los últimos remanentes de los “bosques gigantes” de Podocarpaceae en los Andes tropicales

MODELOS ALOMÉTRICOS PARA ESTIMAR EL ALMACENAMIENTO DE CARBONO DE BOSQUES MONTANOS BAJOS EN EL SUR DEL ECUADOR

En Ecuador existen bosques montanos bajos de gran importancia biológica que proveen de servicios ecosistémicos como el almacenamiento de carbono. Por esta razón, se desarrolló una investigación que permitió elaborar modelos alométricos mediante la cuantificación de carbono en el bosque montano bajo. Se estableció una parcela permanente de una hectárea y se midieron todos los árboles con diámetro a la altura del pecho (DAP1,30m) ≥ 5 cm. Las variables que se usaron para la generación de los modelos fueron DAP y altura total (ht). La biomasa arbórea fue de 322,37 t ha-1 y el carbono total estimado fue de 161,07 t ha-1. En los modelos alométricos del estrato arbóreo, las variables que mejor se ajustaron fueron DAP, DAP2 y ht. La familia botánica con mayor biomasa (69,95 t ha-1) y carbono (34,98 t C ha-1) fue Moraceae, que conjuntamente con Lauraceae, Myristicaceae y Rubiaceae almacenan el 57% de carbono (91,55 t C ha-1) del bosque montano bajo. De las 179 especies botánicas registradas, las especies Pseudolmedia laevigata, Nectandra reticulata, Otoba parvifolia, Vochysia paraensis, Ficus sp. y Elaeagia obovata almacenan el 51% (81 t C ha-1) del carbono total estimado

Eventos climáticos extremos y migración interna en Guatemala, un análisis basado en percepciones de expertos

This research contributes to a better understanding of internal migration in Guatema­la which faces the extreme climate events (ECE) expected on the framework of climate change. This analysis was based on the livelihood of the community. The information was obtained from semistructured interviews applied to experts and literature review. The results showed that migration is closely linked to the livelihoods of communities, since the consequences of the ECE alter the conditions of a territory. However, the decision to migrate is influenced by the socio­economic conditions of the people. The results also indicated that food security acts as a channel through which the ECE influence migration.Contribuye a comprender la migración interna en Guatemala frente a los eventos climáticos extremos (ECE) en el marco del cambio climático. Este análisis se hizo con base en los medios de vida de la comunidad. La información se obtuvo de entrevistas semiestructuradas aplicadas a expertos y de revisión bibliográfica. Los resultados encontrados revelan que la migración está estrechamente ligada a los medios de vida de las comunidades porque los ECE cambian las condiciones de un territorio. Sin embargo, la decisión de migrar se ve influida por las condiciones socioeconómicas de las personas. También se encontró que la seguridad ali­mentaria es un canal a través del cual los ECE tienen impacto en la migració

Composted sewage sludge with sugarcane bagasse as a commercial substrate for Eucalyptus urograndis seedling production

Sewage sludge can be used as a source of organic matter and nutrients, whereas sugarcane bagasse can be used as a decompaction material; by composting a mixture of the two, a low-cost substrate for forest nurseries can be obtained. This research investigated the use of composted sewage sludge with sugarcane bagasse (CSB) as a commercial substrate in nurseries to grow seedlings of the hybrid clone Eucalyptus urograndis. Several CSB treatments were evaluated in comparison with a control (no P addition) and a commercial substrate (CS). Before composting, CSB was conditioned with P to increase its final concentration: CSB+1.5, 3.0, and 4.5% triple superphosphate (TP) or reactive phosphate (RP). After 120 d, the Eucalyptus response to all eight substrates was assessed by: i) plant morphological traits (H, height; D, diameter; SB, shoot biomass; RB, root biomass; TB, total dry biomass; GCI, green color intensity; and root system quality) and ii) chemical parameters of shoots and roots. Significant differences among treatments were ascertained using an ANOVA, and variability was interpreted using principal factor analysis (PFA). The treatment with CSB+3% TP (TP3.0) exhibited statistically (p < 0.05) higher performance in regards to morphological parameters (H, D, SB, TB) and the nutrient contents of shoots and roots (N, P, Ca, Na, Mn, Zn, and Cu) than the other treatments and control. The results suggest that B and K could play a fundamental role in both the observed variability and the improved plant performance in the TP3.0 substrate. PFA also showed i) the key role of OM as the primary source/sink of some pivotal macronutrients/heavy metals and ii) the existence of important antagonistic/synergistic effects between elements as a primary driver affecting the concentration/behavior of elements in the shoot/root system. Overall, the research demonstrated that with an addition of only 3.0% TP, the CSB performance was better than the most commonly used and widespread commercial substrate in industrial forest nurseries