Space-time configurations of solute input and biological uptake in river systems traversing limestone uplands (Yorkshire Dales, northern England)

摘要: Solute concentrations, including major plant nutrients, are surveyed from sampling during 1985–89 in river systems variably influenced by upland Dinantian (Carboniferous) limestone. Concentrations of most ions generally increase downstream, but there widespread dilution effects after rainy periods for and local depletions mostly biological origin nutrients. In the upper reaches, these develop mainly under low flow influence benthic algae macrophytes; they affect inorganic C as HCO3- plus dissolved gaseous CO2 soluble reactive forms Si, N P. Inflow – outflow differences an lake result on constituents also Ca+ K+. Experimental injections NH4-N, PO4-P K+were made to acid headwater River Swale, together with Na+ Cl- supposed conservative reference ions. Uptake is insignificant K+ marked NH4-N PO4-P; residual percentage decreases exponentially time. Relative rates net uptake per unit time greater P than larger conditions higher velocity algal growth. Although limestone lacking some regions, where atmospheric inputs appear predominate, overall its chemical denudation Ca2+ HCO3-provides solute flux well karstic headwaters highest values limited CaCO3 saturation.