RESUMEN
Understanding the effects of different production systems on arbuscular mycorrhizal fungi (AMF) can help to interpret interactions between their components and to define management strategies. As a result, our study was conducted on soils under three coffee production systems (one homogeneous and two heterogeneous) and in a native forest located in the Bahia state, Brazil. This study aimed to answer the following questions: 1) Does the organization and management of the coffee production system affect the occurrence and diversity of AMF?; and 2) Is the seasonality effect similar between systems? To do so, soil samples (0-10 cm depth) were collected at two times of the year (rainy and dry). Number of spores (NS) and average richness did not show differences between the systems, only between seasons. There was a reduction in NS in the dry season (1.4 and 2.7 spores g-1 soil) in relation to the rainy season (3.8 to 12.5 spores g-1 soil). The influence of coffee production systems was observed in the presence and absence of some AMF species. The AMF community was shown to be related to the plant species composition of the system, which was reflected in the dissimilarity of heterogeneous systems in relation to the coffee monoculture system.
Asunto(s)
Micorrizas , Café , Bosques , Hongos , Raíces de Plantas/microbiología , Suelo , Microbiología del SueloRESUMEN
The present work aimed to evaluate the influence of different eucalyptus hybrids on the edaphic macrofauna community. It is hypothesized that the density and diversity of edaphic fauna are influenced by the quantity and quality of the litter deposited by the different hybrids on the soil surface. The study area is in the city of Vitória da Conquista (BA) and consists of seven eucalyptus hybrids, one from sexual reproduction (seminal) and six from asexual (clonal) reproduction. Sampling of the soil macrofauna was performed by the Tropical Soil Biology and Fertility method. All visible invertebrates were collected and identified at the level of large taxonomic groups. The relative density, group richness, and diversity index were calculated. Hybrids did not influence the total density and richness of the soil macrofauna. However, it was possible to observe changes in litter accumulation and composition, and as a result in the diversity indexes and in the presence or absence of macrofauna groups. Among the studied hybrids, those from Eucalyptus urophylla (seminal, 1335 and 1249) promote greater macrofauna diversity and favor the occurrence of detritivores organisms, suggesting the occurrence of better quality and more palatable litter for the edaphic fauna.
Asunto(s)
Eucalyptus , Suelo , Animales , Biodiversidad , Ciudades , InvertebradosRESUMEN
Wastewater from oil exploration may contain substances that can alter the diversity of soil organisms. This study evaluated whether produced water treated by filtration or reverse osmosis and glutaraldehyde from reverse osmosis treatments negatively affected the mesofauna in an irrigated area. In the field, irrigation with produced water treated by reverse osmosis and filtration influenced Hymenoptera and Cosmochthonius sp., while Entomobryomorpha springtails were affected only by the reverse osmosis water. In the ecotoxicological tests, reproduction in the springtail Folsomia candida was inhibited by the reverse osmosis treatment, while reproduction in the earthworm Enchytraeus crypticus was affected by both water treatments. Although glutaraldehyde did not affect the survival of F. candida, the reproduction was inhibited (EC50 = 44.4 mg/L). No adverse effect of glutaraldehyde was observed on reproduction or survival of E. crypticus. These results indicate that produced water, when used in irrigated agriculture, may affect soil functional mesofauna.