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WHAT HAPPENS IN WATERS?  -WHAT DETERMINES WATER QUALITY IN BOREAL LANDSCAPE NORMALLY?  Variation in water quality in the boreal landscape is mainly caused by landscape characteristics. The major influence on stream water nutrients and pH is proportion of peatlands in the catchment. .....  -FIRE WE KNOW  -ACID  Postfire water quality is determined by what is hydrologically exported to streams and lakes.  After fire there is an increase of available nutrients in the soil, soil that can leech out,  mainly caused by an increase in soil pH which is associated to with  an increase in exchangeable cations (e.g.Ca2+,Mg2+, and K+, and the anion SO42)  in soil \cite{gonzalez-perez_effect_2004}. Micronutrients (e.g. Fe, Mn, and Cu) behavouir, although less studied, seem to be less vulnerable to leech out \cite{certini_effects_2005}. There is also a an increased availability of soulable P post-fire but this effect is suggested to be short and little is leeched out \cite{certini_effects_2005}.  Soil organic nitrogen is either volatilised or largely converted into inorganic forms (i.e. NH+4 and NO-3). NO-3) \cite{certini_effects_2005}.  Nitrite is mainly formed from NH+4 through nitrification up until months after the fire (Covington and Sackett 1992). Both NH4+–N and NO3–N are available to plants, but with a sparse or non-existing vegetation cover after a severe fire, these compounds are leached out. Although, ammonium is assumed to be held by the soil because it adsorbed onto negatively charged surfaces of soil particles (Mroz et al.1980), a study observed a NH+4 pulses that lasted over 3 2  growing seasons (Grogan et al. (2000) ). Areas which have higher concentrations of stored S from past acid precipitation or have large areas of peatlands in the watershed may have aggravated losses of S and H+ after drought and fire \cite{bayley_effects_1992}.  ----------  A majority of studies also show post-fire peaks in sulphate (SO42-), chloride (Cl-) and/or base cation concentrations (e.g. Bayley and others, 1992; Carignan and others, 2000; Mast and Clow, 2008; Bladon and others, 2014). Again, peaks in these solutes can be attributed to their release via pyrolysis from biomass and soil organic matter, and to the after-effects of fire such as soil drying and cracking. Soil modifications may be particularly important in organic soils, where elements such as sulphur (S) are stored in reduced forms, and are therefore susceptible to oxidation and subsequent leaching. The effects of these solute losses on freshwater acidity depend on the relative balance of base cation and acid anion leaching. In the Ontario lakes studied by Carignan and others (2000), increases in NO3-, SO42- and Cl- were counterbalanced by increases in base cations, and alkalinity and pH were therefore unaffected. However an earlier study in the same region by Bayley and others (1992) did find evidence of post-fire acidification, and a recent study of acid-sensitive lakes in Norway found severe short-term acidification, and associated high aluminium concentrations, during the immediate post-fire period (Lydersen and others, 2014).  -------------------  ----  The duration of these effects appear variable: Bladon and others (2008) and Carignan and others (2000) report peak NO3- concentrations in the first year post-fire, returning to reference levels within 2-3 years; Hauer & Spencer (1998), Mast and Clow (2008) and Mast (2013) report elevated NO3- concentrations for periods of 4-5 years after fires at Northwestern US forest catchments; Bayley and others (1992) recorded elevated NO3- for nine years after a fire in Ontario; and Smithwick and others (2005) suggest that modifications to the overall ecosystem N cycle can extend for decades after major fires.   -----  -ACID  -LOSSES...eg N,P, CATIONS  Fire can also transform organic N to inorganic forms that are available to plants, but with poorly developed post-fire plant communities, this N can be easily exported to streams and lakes (Smith 2011)(