Water quality variation along streams with similar agricultural development but contrasting riparian vegetation.

摘要: Abstract We measured water quality along four Australian tropical streams in two catchments with similar agricultural development (mainly sugarcane growing) but contrasting riparian vegetation (intact native rainforest vs. exotic weeds). There were strong gradients and consistent differences between streams. The most significant pattern was an increase nitrate + nitrite (NOx) concentration distance downstream, reflecting the increasing discharge proportion of fertilized land catchment, indicating continuous export contaminated groundwater all Measuring longitudinal gradient critical to interpretation data enabled us confidently detect NOx concentrations loads significantly lower greater regression analysis suggested some N-stripping zone, albeit insufficient meet regional water-quality guidelines. Our results demonstrate benefit accounting for comparing among detecting effect at a catchment scale, that adequate reduction can only be achieved by reduced fertilizer application rates catchments.