500 mg kg-1), regardless of OM concentrations. Cocoon production decreased in the soils with Cu concentrations below 500 mg kg-1 when OM concentrations were below 3.5%. In contrast, cocoon production did not vary when OM concentrations were above 3.5%. The same effect of OM was observed on juvenile production. In this case, the threshold for OM concentration was 2.5%. It was concluded that it is important to consider OM concentrations in order to predict the biological response of earthworms in these soils.]]>

El objetivo del trabajo fue evaluar la toxicidad del cobre y arsénico en suelos agrícolas, mediante bioensayos estandarizados de toxicidad aguda y crónica sobre Eisenia foetida y relacionar la respuesta de ésta con las concentraciones de cobre y arsénico en los suelos. Los suelos agrícolas fueram muestreados en las inmediaciones de áreas mineras en la cuenca del río Aconcagua, Chile. E. foetida expuesta a los suelos estudiados mostró una baja mortalidad, indicando la ausencia de toxicidad aguda. Además, se observó una disminución en la producción de capullos y desarrollo de juveniles, indicando la existencia de toxicidad crónica. Dicha disminución fue relacionada con las concentraciones de cobre y arsénico en los suelos. El cobre y arsénico en conjunto disminuyeron la producción de capullos, mientras que sólo el arsénico disminuyó el desarrollo de juveniles. Suelos agrícolas provenientes de áreas mineras de la cuenca poseen potenciales características tóxicas para el desarrollo de la macrofauna edáfica.

Recebido em 5/3/09; aceito em 19/8/09; publicado na web em 11/1/10 ASSESSMENT OF COPPER TOXICITY IN SOILS USING BIOMARKERS OF OXIDATIVE STRESS IN Eisenia foetida.Copper toxicity in soil was evaluated using biomarkers of oxidative stress (catalase enzyme activity, superoxide dismutase and lipid peroxidation) in the earthworm Eisenia foetida. Agricultural topsoils from mining areas of the Aconcagua river basin were collected. Total copper concentrations were in the range of 94-959 mg kg . Earthworms exposed to soil with exchangeable copper concentrations above 32 µg kg -1 showed an increase in catalase activity. Parameters of antioxidant activity were more sensitive than the weight change and thus can be used as appropriate biomarkers in Eisenia foetida.

A number of agroecological practices have been proposed for assessing soil quality. Several physical soil properties have been shown to be important for determining soil quality by using the sustainability index (SI) and the cumulative rating approach. The main aim of the study was to determine the effects of different agroecological managements on the physical properties of a Mollisol in the Mediterranean central Chile. In addition, some physical properties were selected to compare the soil quality among different agroecological management practices and highly mechanized intensive systems by using the SI and cumulative rating approaches. An experimental field was defined in an area of 3.5 ha in 2014. Four sites with different agroecological practices were selected in 2019 to assess soil physical properties: rainfed Mediterranean annual prairie - no tillage (1-S), irrigated perennial prairie with deep-root species - no tillage (2-N), irrigated annual and perennial prairie - conventional tillage (4-S), irrigated vegetables and flowers - minimum tillage (4-N); an avocado orchard with traditional management was used as the control. Soil organic carbon and the following soil physical properties were selected to assess SI and CR: bulk density, total porosity, void ratio, air capacity, fast-drainage pores, relative field capacity, hydraulic conductivity, structural stability index and unavailable water pores. The applicability of the selected physical indicators to the SIs of agroecological management practices compared with the control was demonstrated. The cumulative rating index (CR) for each land use showed that all agroecological practices constituted sustainable soil management (25≤CR<30), whereas the avocado orchard showed the least sustainable management (30≤CR<40), and a change in soil use is recommended.

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