Cd accumulation in soil from beachcast application : A long-term prediction of its reintroduction for bio-fertilisation in Gotland, Sweden

• The ecological consequences of using beachcast compost as an agricultural resource input merit study. Using beachcast compost as a biofertiliser has multiple positive effects on agroecosystems, while also serving to remedy the negative effects on marine ecosystems caused by excessive beachcast production due to eutrophication. This process thus presents an opportunity to contribute to circular nutrient management and the development of sustainable agricultural, but it may also result in accumulation Cd (Cd) in the soil. In Gotland, Sweden, an example of cross-scale interaction between marine and agricultural domains has emerged from a national policy subsidising beachcast harvesting, which may help reintroduce the historical tradition of using beachcast in agriculture. To estimate potential risks, a field experiment and Cd mass balance were conducted to predict the rate of Cd accumulation, changes in soil Cd fractions, and potential beachcast application methods that avoid Cd soil accumulation. In the scenario where the maximum Cd input from beachcast compost is set to the same threshold as the level established for sewage sludge—0.75 g ha–1 year–1—beachcast compost with a Cd content of 1.5 mg kg–1 dw (the EU threshold for biofertilisers) could be applied in an amount of approximately 2000 kg ha–1 per year (one-tenth of the amount applied in this study). Therefore, the long-term effects of Cd soil accumulation resulting from continuous application of beachcast as fertiliser on agroecosystems cannot be disregarded and are of global relevance.  

Ämnesord

LANTBRUKSVETENSKAPER  -- Lantbruksvetenskap, skogsbruk och fiske -- Markvetenskap (hsv//swe)

AGRICULTURAL SCIENCES  -- Agriculture, Forestry and Fisheries -- Soil Science (hsv//eng)

Nyckelord

beachcast

biofertiliser

soil

cadmium

accumulation modelling

Publikations- och innehållstyp

vet (ämneskategori)

ovr (ämneskategori)