Biological effects of Wood Ash Application.

• The Swedish National Board of Forestry recommends recycling of wood ash for two main reasons: 1) to avoid depletion of essential soil nutrients, and 2) to reduce the harmful effects of acidification of surface waters. There is no doubt that recycling of wood ash to boreal forests will become a major industry in the near future. Much research is conducted regarding the effects of wood ash application on forest growth. Present studies show that, generally speaking, forest growth can be increased on wood ash-ameliorated peatland rich in nitrogen. On mineral soils, however, no change or even decreased growth has been reported. The effects on ground vegetation are not very clear, as well as the effects on fungi, soil microbes and soil decomposing animals. The discrepancies between different studies are for the most part explained by abiotic factors such as variation in fertility among sites, different degrees of stabilization and wood ash dosage used, and different time scales among different studies. The lack of knowledge in the field of aquatic ecosystems and their response to ash application is an important issue for future research. The few studies conducted have mainly considered changes in water chemistry. The biotoxic effects of ash application can roughly be divided into two categories: primary and secondary. Among the primary effects is toxicity deriving from compounds in the wood ash and cadmium is probably the worst among these. The secondary effects of wood ash are generally due to its alkaline capacity and a release of ions into the soil and soil water, and finally, watercourses and lakes. The present review aims to summarize current knowledge in the topic of wood ash application to boreal forest and aquatic ecosystems, and the different effects derived from these actions. ABBREVIATIONS: WAA, Wood ash application; MT, metric tonnes

Ämnesord

NATURVETENSKAP  -- Biologi (hsv//swe)

NATURAL SCIENCES  -- Biological Sciences (hsv//eng)

Nyckelord

wood ash

forest growth

ground vegetation

fungi

soil fauna

aquatic life

toxic

Biology

Biologi

Publikations- och innehållstyp

ref (ämneskategori)

art (ämneskategori)