شماره مطلب: 416

Cadmium availability to plants in relation to major long-term changes in agronomy systems

نویسنده: 
M.J. Mench
انتشارات: 
elsevier
تعدات صفحات: 
13
Cd concentrations in food products may be controlled to some extent by reducing metal inputs in agrosystems. However,Cd is available to plants, so the management of its residual fraction in soil must be considered. Differential Cd uptake amongcrop species and cultivars is well known, but the long lasting effects of other agricultural practices are less clearlyunderstood. Generally, cropping systems affect the physico-chemical properties of soil. These may produce subsequentchanges in metal mobility and bioavailability. The effects of agricultural practices, e.g. crop rotation, fertilization, tillagemethod, and stubble treatments, were therefore examined. Attention was mostly focused on Cd concentrations in potatotubers and cereal grains that are the major plant-derived contributions to the European diet. Results from long-term fieldexperiments at well separated locations indicate that: Cd concentration in grain is highest in wheat grown after a legumesuch as lupins, and lowest in wheat grown after a cereal; Cd in wheat grain and potato tubers can increase with increasingrates of nitrogen irrespective of the crop rotation; Cd in wheat grain can be influenced by Zn supply to the plant; a higherconcentration of Cd is found in wheat grain in continuous wheat under direct drilling, compared to reduced till orconventional cultivation; high Cd can be measured in potato tubers growing on neutral or alkaline soils that have relativelylow Cd concentration, and so the practice of adding lime to decrease Cd in tubers is questionable; the effects of stubblemanagement and fallow in crop rotation are too inconsistent to allow conclusions to be drawn. Maximum increase in Cdconcentration resulting from changes in the cropping system could be 0.04 mg kgy1 FW in wheat grain and 0.03 mg kgy1FW in potato tubers. q1998 Elsevier Science B.V.
کارگروه: 
حجم: 
175.87KB

نظرات

  • دیدگاه های ارسال شده توسط شما، پس از تایید در وب منتشر خواهد شد.
  • پیام هایی که حاوی تهمت یا افترا باشد منتشر نخواهد شد.
  • پیام هایی که به غیر از زبان فارسی یا غیر مرتبط باشد منتشر نخواهد شد.