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Purpose: Without a proper treatment, pigeon dropping waste (PDW) in the urban environment is a sanitary risk for the population because of nasty and irritating odors, a very high content of ammonium, and the presence of pathogens. This study deals with the recycling of PDW from a dovecote, situated in a public city plaza, to achieve its stabilization and eliminate sanitary risks. Method: Composting of PDW with other locally available lignocellulosic residues (sawdust and chipped tree pruning) and vermicomposting employing Eisenia fetida earthworms was applied. Two designs were selected for the vermicomposting stage: (1) Sectorized, with a zone with earthworms and another zone of composted PDW with gradual incorporation to the first one and, (2) Integrated, consisting of the composted PDW, with E. fetida in the entire solid. Results: The composting allowed a partial stabilization of the original mix of PDW, given its highly elevated initial content of ammonium (8693 mg kg-1). The combined processes almost eliminated the ammonium present (> 99% reduction) and the action of earthworms shortened the maturation time. Organic matter and electrical conductivity of the solids had important reductions. The treatment affected the resulting characteristics of the solids obtained but the germination index was above 80% in both cases. Conclusions: Both designs allowed the obtention of two mature, non-phytotoxic vermicomposts. The sectorized vermicompost had better properties and had the advantage of being obtained with fewer initial number of earthworms. Research Highlights • Pigeon dropping waste was recycled by combined composting-vermicomposting process. • Two vermicomposts were obtained by different sectorized and integrated designs. • High ammonium content was reduced and nasty odors and pathogens were neutralized. • Sectorized design produced a better vermicompost with fewer number of earthworms. • Undiluted extracts of the vermicomposts rendered germination indexes over 80%.

Purpose A combined treatment of composting and vermicomposting of poultry litter (PL), rice hulls (RH) and/or eucalyptus sawdust (ES) was carried out in order to obtain a high-quality organic fertilizer and avoid the environmental problems associated with the use of raw poultry manure and fresh agricultural waste materials. Methods Three composting mixtures were made at volume proportions: 1:3 RH/PL (M1); 1:2 ES/PL (M2) and 0.5:1:2 RH/ES/PL (M3). Composting (120 days) followed by vermicomposting (90 days) using earthworms (Eisenia fetida) were conducted during the autumn-winter season, outdoors and sheltered. Moisture content was kept at 60-70%. Physicochemical (pH, electrical conductivity, lignin, total carbon and nitrogen, organic matter, ammonium and specific cations), total microbial activity (fluorescein diacetate hydrolysis) and microbiological parameters were recorded throughout both processes. Phytotoxicity tests were lastly performed by means of Lactuca sativa, L. seed germination, to compare the quality of the organic fertilizers obtained. Results A sequential compost-vermicompost process enhanced the properties of the final products. Particularly, electrical conductivity was markedly lower in all vermicomposts (1.81-2.28 mS cm-1) and within the values recommended for the growth of sensitive plants; microbial activity reached 187.1-203.8 µg FDA gsoil-1 h-1. Germination Index values in vermicomposts were greater than 60%, indicating the high quality of the products obtained, being the mixture 0.5RH:1ES:2PL, the one which showed better quality and higher maturation degree. Conclusion The system that combines both processes (composting+vermicomposting) was effective to produce a stabilized organic fertilizer from poultry litter with other waste organic materials.

La edafofauna comprende una gran variedad de organismos que intervienen en numerosos procesos del suelo, afectando tanto el crecimiento de la vegetación como el mantenimiento de la productividad. El objetivo del trabajo fue estudiar la abundancia y composición de la macrofauna en relación a tres ambientes con uso del suelo, características edáficas y composición vegetal diferentes, localizados en el vivero forestal de Recreo Sur (Santa Fe, Argentina). Se extrajeron de cada ambiente 15 bloques de suelo en primavera 2013 y otoño 2014 siguiendo el método estándar TSBF. Se determinaron densidad, número de familias y grupos funcionales por ambiente. Se colectaron un total de 5344 individuos pertenecientes a 17 órdenes y 56 familias. La densidad media de la macrofauna mostró diferencias entre ambientes (P< 0,05), destacándose Parquizado con el valor más alto (966 ind.m-2). El número de familias fue mayor en Pastizal (43) siguiendo Plantación (31) y Parquizado (29). Los taxa más representativos fueron Hymenoptera (47,93%), Haplotaxida (26,83%), Isopoda (8,29%), Coleoptera (7,20%), Chilopoda (3,07%) y Araneae (2,35%). Los grupos funcionales mostraron diferencias por ambiente (P< 0,05), siendo los más abundantes los ingenieros del suelo (745 ind.m-2) y los detritívoros (151 ind.m-2) en Parquizado y herbívoros en Pastizal (28 ind.m-2). El grupo depredadores no mostró diferencias entre ambientes (P> 0,05). Nuestros resultados muestran que las comunidades de macrofauna variaron, no sólo en relación al uso del suelo sino también por la composición vegetal presente en los ambientes del vivero forestal.

Atrazine is one of the most used herbicides and its over-application in fields can affect the soils and their associated biota. In this work, earthworms (Eisenia fetida) were exposed to different concentrations of atrazine to assess possible sublethal harmful effects. In the search for reliable biomarkers of these effects, acetylcholinesterase (AChE), alkaline phosphatase (ALP) and lactate dehydrogenase (LDH) activities were measured as well as behaviour and population biological parameters such as biomass, growth and production of cocoons. It was found that biomass changes were not significantly affected by atrazine presence and after 28 days the increment was around 18.3–27.3%. Protein content in earthworms was reduced in the presence of atrazine after 28 days. The lower atrazine concentration (2 mg Kg−1) affected in the shortest term (7 days) the rate of cocoon production and increased LDH activity and, especially, the AChE activity in around 40%. The presence of a higher concentration (10 mg Kg−1) of the herbicide reduced one third of the number of total cocoons, affecting the reproduction. ALP was the least sensitive biomarker to atrazine exposure. When exposed to up to 10 mg Kg−1 of atrazine, E. fetida showed a tendency to rebalance and maintained its general health.

Las lombrices de tierra constituyen un componente importante en la fauna del suelo contribuyendo activa y beneficiosamente en su estructura y fertilidad. Estos organismos son sensibles ante distintos manejos y grados de perturbación del suelo respondiendo como bioindicadores de la «salud» del mismo. El Cinturón Hortícola Santafesino (Santa Fe, Argentina) exhibe diferencias no sólo en tipos de cultivos sino también en sistemas de producción y condiciones de trabajo. El objetivo del estudio fue determinar la abundancia y diversidad de la oligoquetofauna en los suelos con distintos tipos de manejo en las localidades de Ángel Gallardo y Monte Vera (Dpto. La Capital, Santa Fe - Argentina). Se seleccionaron tres agroecosistemas: labranza convencional (LC), siembra directa orgánica (SDO) y siembra directa (SD). En cada campo se realizaron dos muestreos, correspondiendo uno a la estación verano y el otro a otoño de 2008. Se analizaron algunas propiedades físicas y químicas de los suelos como también residuos de plaguicidas. La densidad de oligoquetos presentó diferencias por estación y sistemas de producción (p = 0,001) destacándose el sitio de SDO con el mayor número de individuos en las dos estaciones muestreadas. La taxocenosis constó de dos familias: Lumbricidae y Megascolecidae, y tres especies: Aporrectodea rosea, Aporrectodea trapezoides y Amynthas morrisi. La diversidad fue baja (H'= 0,33), siendo A. rosea la especie más común en los sitios muestreados y A. trapezoides la más abundante, incorporándose estaúltima a la lista de oligoquetos para la zona hortícola ya que en estudios anteriores no se hallaba registrada. La composición y estructura de la taxocenosis de lombrices de tierra se ve afectada no sólo por las condiciones ambientales y labores de producción, sino también por los parámetros físicos y químicos del suelo, que en conjunto condicionan la sensibilidad de la oligoquetofauna.Earthworms are an important component of soil fauna, contributing actively to improve soil structure and fertility. These organisms are highly sensitive to different soil managements and degrees of soil disturbance and were therefore adopted as biomarkers of the soil «health». The Cinturón Hortícola Santafesino (Santa Fe, Argentina) exhibits a large variability in crop species, production systems and working conditions. The aim of this study was to determine the abundance and diversity of earthworms in soils under different types of managements near the villages of Ángel Gallardo and Monte Vera (Dept. La Capital, Santa Fe, Argentina). The three agroecosystems selected were: conventional tillage (LC), notillage with added organic amendments (SDO) and no-tillage (SD). Two samplings were conducted in each field: one in summer and the other in fall of 2008. In addition, some physical and chemical properties of soils were analyzed, as well as the presence of pesticide residues. The density of oligochaetes showed significant differences between seasons and production systems (= 0.001). The SDO site had the greatest number of individuals in the two sampled seasons. The taxocenosis consisted of two families: Lumbricidae and Megacolescidae, and three species: Aporrectodea rosea, Aporrectodea trapezoides and Amynthas morrisi. The diversity was low (H'= 0.33), resulting A. rosea the most common and A. trapezoides the most abundant species, respectively. A. trapezoides was incorporated to the earthworm records of the area because it had never been reported in previous studies. The composition and structure of the earthworm's taxonomy is not only affected by the different agricultural practices and the edaphic and environmental conditions, but also by the soil´s physical and chemical properties that influence the oligoquetofauna sensitivity.