Populações de minhocas em sistemas agroflorestais com café convencional e orgânico

Abstract

RESUMOObjetivou-se, neste estudo, determinar se as populações das minhocas são alteradas em função do manejo do café (Coffea arabica) em Turrialba, CostaRica. Os seguintes sistemas de cultivo do café foram estudados: a pleno sol (PS) e sombreado com eritrina, Erythrina poeppigiana (E); terminalia, Terminalia amazonia (T) e cashá, Chloroleucon eurycyclum (Ab). A hipótese foi de que o manejo orgânico do café e o fornecimento da serapilheira de melhor qualidade favoreceria a diversidade, a densidade e a biomassa das minhocas. As populações das minhocas foram alteradas, em função do manejo com insumos sintéticos ou orgânicos , sendo a densidade menor no café a pleno sol. Entre as espécies utilizadas no sombreamento, a eritrina parece limitar a abundância das minhocas. Contudo, favorece a diversidade das mesmas, tendo sido registradas duas espécies de minhocas com papéis ecológicos diferenciados, Pontoscolex corethrurus, endogeica e Metaphire californica, anécica; ao contrário dos demais tratamentos, onde somente foi encontrada a primeira espécie, considerada cosmopolita com distribuição pantropical. Termos para indexação:Coffea arabica, microclima, biodiversidade, fauna do solo, sombreamento. ABSTRACTThe aim of this study was to determine whether the populations of the earthworms are altered by coffee systems in Turrialba, Costa Rica. The following coffee management systems were studied: the sun and shading with Erythrina poeppigiana; terminalia, Terminalia amazonia or cashá, Chloroleucon eurycyclum. The hypothesis was that the organic management of the coffee and the litter input of better quality would favor the diversity, the density and the biomass of the earthworms. The populations of earthworms were differentiated with the synthetic or organic input. However, the density was lower in the coffee under the sun anyone the used species in the agroforestry, the eritrina seems to limit the abundance of the earthworms, but it favors the diversity of the same ones, being registered two species of earthworms with differentiated ecological roles, Pontoscolex corethrurus, endogeic, specie cosmopolita with pantropical distribution and Metaphire californica, anecic. On the contrary of other treatments where only the first species was found.

Bioindicators of soil quality in coffee organic cultivation systems

“…The area with coffee under full sun had low total density and median richness, as reported by Aquino et al (2008a), who compared coffee crops under full sun and shaded crops with arboreal species. The presence or absence of living perennial mulch regulated the edaphic macrofauna, as demonstrated by Lima et al (2010), when comparing soil macrofauna and chemical attributes to different systems.…”

“…Coffee originally came from the deciduous forests in Ethiopia and Sudan, and has been associated with understory conditions. Latin American countries, such as Colombia, Costa Rica, Ecuador, and Guatemala, have been using shading as a technique for a more rational and conservationist use of the soil in coffee areas (Aquino et al, 2008a;Morais et al, 2009), in accordance with the precepts of organic agriculture sustainability.…”

“…Beer (1998) reported soil accumulation of up to 14 Mg ha -1 per year of residues originating from fallen leaves and pruned material, in dense coffee cropping. Aquino et al (2008a), who evaluated earthworm populations in agroforestry systems with conventional and organic coffee crops, found lower earthworm density under full sun and that shading from Erythrina favored earthworm diversity. Therefore, conservationist practices, including better quality organic matter input, can result in greater earthworm abundance (Ortiz-Ceballos & Fragoso, 2004).…”

Soil macrofauna in organic and conventional coffee plantations in Brazil

“…populations (Bartz et al 2009). Aquino et al (2008), when surveying earthworm populations, also found great diversity, including P. corethrurus, which is an exotic and cosmopolitan species. The presence of other exotic species, as A. corticis and D. gracilis, as well as some specimens of the family Megascolecidae and of the genus Amynthas may represent a problem at the ecological level, because these organisms are well distributed and very adaptable to different environments, posing a risk to the survival of native species (Brown et al 2006).…”

Spatial Distribution of the Fauna of the Soil on the Long-Term System of Direct Sowing

“…The sowing is made with appropriate machines that open furrows on the lines of planting, in which the seeds are deposited (AQUINO et al, 2008), GODOY et al (2007), observed that the direct sowing system, when compared with the conventional tillage system, provides a higher density of saprophytic, geophagic and predators organisms of edaphic community, which can promote the control of several agricultural pests, and reduce the use of insecticides.…”