Nitrogen and phosphorus in runoff from grassland with buffer strips following application of fertilizers and manures

Abstract

Abstract. We examined whether nitrogen (N) and phosphorus (P) export was enhanced from grassland receiving inorganic fertilizer and manures typical of intensive livestock production. Buffer strips were included in the study to determine if they could reduce nutrient export. Hillslope plots receiving granular inorganic fertilizer, liquid cattle slurry and solid cattle manure (FYM) were compared using rainfall simulation for 4 storms on consecutive days at 22 mm h‐1 and 35 minutes duration. The plots were hydrologically isolated in a randomized block layout of 4 treatments × 3 replicates and measured 30 × 5m; the upper 20m received either fertilizer, slurry or FYM, while the lower 10 m acted as an unfertilized grass buffer strip. Nitrogen and P export in surface runoff from grassland receiving inorganic fertilizer exceeded that from FYM or slurry treatments; concentrations up to46mgN1‐‐1 and 15 mgP1–1 were recorded. Sixty eight % and 62% of the N from FYM and slurry respectively, was exported in organic form. Seventy four % (FYM) and 39% (slurry) of the P was in particulate or dissolved organic form. The buffer strip reduced N export in surface runoff by 94% and P export by 98% from inorganic fertilizer plots. A 75% reduction in N export was recorded from the buffer zone below slurry plots but only a 10% reduction in P, with most P remaining in the particulate or dissolved organic fraction. There was no significant difference in N export from the buffer zone between the inorganic fertilizer treatment and the untreated control.

Supply of an ecosystem service—Farmers’ willingness to adopt riparian buffer zones in agricultural catchments

“…This is driven by reduction of sediment, pathogen and nutrient loads (Heathwaite et al, 1998;Line et al, 2000;Reed and Carpenter, 2002;McKergow et al, 2003;Sharply et al, 2003;Young and Briggs, 2005;Cors and Tychon, 2007;Haygarth et al, 2009;Wilcock et al, 2009). As noted by Lynch et al (2001) such findings have encouraged some policymakers to assign a high priority to establishing riparian buffers.…”

Nitrogen, Phosphorus and Potassium Losses in a Grazing System with Different Stocking Rates in a Volcanic Soil

“…Peaks of RP concentration were measured associated to spring P fertilizer application during all years and were greater than those reported by McColl et al (1977) for grasslands on volcanic soils. The high RP concentrations after TSF addition was probably due to the direct transport of fertilizers granules in runoff after the application and because TSP granules were rapidly solubilized by surface runoff (Heathwaite et al, 1998).…”

The Potential of P Loss from Livestock Farms to Watercourses in Wensleydale; A Risk Mapping Approach

“…Similarly, Edwards [30] published that higher P surpluses were associated with grassland farming systems ( Table 2). In this sense, other studies have yielded that a common practise among farmers is to apply fertiliser on the basis of N, not considering concentrations of P already present in the soil [31,32]. Thus, this information can contribute to optimising farm management, in particular nutrient management.…”

“…However, the sum of available P from slurry and FYM results in the highest value. This may link to some studies that highlighted that farmers normally undervalue the N:P:K content of slurry and FYM [31,32].…”

“…Nevertheless, Pearson's correlation tests showed no significance relationship (P < 0.05) between P Index and LU/Ha. across numerous studies [31,35,53,54]. Regarding possible measures implemented to reduce the risk of nutrient loss to freshwaters, 40 of the farms had fenced off its waterways.…”