title: [Interception Effect of Ecological Ditch on Nitrogen Transport in Agricultural Runoff in Subtropical China].
abstract: Interception effects of an ecological ditch, used to control agricultural non-point source pollution in subtropical China, on nitrogen transport in surface runoff were studied by monthly measuring the runoff volume and concentrations of ammonium nitrogen (NH₄⁺-N), nitrate nitrogen (NO₃⁻-N) and total nitrogen (TN) at the ditch inlet and outlet from 2013 to 2014. In addition, differences of NH₄⁺-N, NO₃⁻-N and TN removal were compared between 2013 and 2014. The results showed that the study ecological ditch worked effectively in N removal with average NH₄⁺-N, NO₃⁻-N and TN removal rates of 77.8%, 58.3%, and 48.7%; and their interception rates were 38.4, 59.6, and 171.1 kg · a⁻¹, respectively. The average proportion of NH₄⁺-N and NO₃⁻-N in TN was 47.5% at inlet, and 33.6% at outlet, which was significantly lower than that at inlet (P < 0.01). All hydrophytes in the ecological ditch were replaced by Myriophyllum aquaticum in 2014, which led to the increased average NO₃⁻-N and TN removal rates of 30.5% and 18.2%, respectively, Compared to in 2013. The vegetation of Myriophyllum aquaticum was beneficial to the improvement of N interception in ecological ditch. These findings clearly demonstrated that ecological ditch can substantially reduce N loss from surface runoff and be used as an important technique to prevent agricultural non-point N pollution.
authors: Di
authors: D
authors: Wang
authors: Hong-fang
authors: HF
authors: Li
authors: Feng
authors: F
authors: Liu
authors: Yi
authors: Y
authors: Wang
authors: Yuan-chun
authors: YC
authors: Zhong
authors: Yang
authors: Y
authors: He
authors: Run-fin
authors: RF
authors: Xiao
authors: Jin-shui
authors: JS
authors: Wu
mesh_terms: D000383:Agriculture; D002681:China; D004463:Ecology; D004784:Environmental Monitoring; D009566:Nitrates / Q000032:analysis; D009584:Nitrogen / Q000032:analysis*; D014872:Water Movements; D014874:Water Pollutants, Chemical / Q000032:analysis*
chemical_list: D009566:Nitrates; D014874:Water Pollutants, Chemical; D009584:Nitrogen