Key findings

Key findings from of the ACP to date:

1. Declining Soil Test Phosphorus Trends across catchments
2. Low use of Nutrient Management Plans by farmers
3. Improved nitrogen and phosphorus use efficiency on farms
4. Soil type and geology override soil P level as a predictor of P loss risk
5. P loss to groundwater through the soil can be important in some settings
6. Point sources have a disproportionately large summer influence
7. Closed period is effective but extension is not warranted
8. Sediment losses are low and from roadways, stream banks and beds
9. Importance of Critical Source Areas for targeting mitigation
10. Identified the main influencers on farmers’ nutrient management practices
11. Climate and weather are important pressures on nutrient losses and the response differs depending on catchment typology
12. Groundwater Nitrate below 11.3 mg/L in all 6 catchments
13. Hydrogeological and agronomic factors controlled groundwater hydrochemical signatures
14. Groundwater nitrous oxide was found to be a net source of greenhouse gas emission
15. Dairy expansion can increase loss of N to the environment due to increased N loading
16. A new conceptual model of P loss and retention with new categories of risk assessment for a karst catchment is created
17. Improving river ecological quality requires improved management of sediment inputs and a reduction in point sources
18. E. coli transfers are correlated with P transfers in some catchments
19. There is a need for improved support to knowledge transfer for better farm and soil specific nutrient management planning strategies
20. Improving river ecology requires a reduction in point sources