Future Change and Diffuse Pollutionchallenges,

Transcription

1 Catchment Change Network July 2010 Future Change and Diffuse Pollutionchallenges, gaps and opportunities Phil Haygarth and many others Centre for Sustainable Water Management, Environment Centre, Lancaster University

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4 Diffuse pollution in a changing system...

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7 A framework for diffuse pollution the transfer continuum 2. MOBILISATION describes the start of the journey from soil or source P, either as a solute (solubilised) or attached to colloids and particles (detached) 1. SOURCES include fertilizer applications, defecation from grazing animals, spreading of manure on soils Sub-surface flow Infiltration-excess flow Saturation-excess flow 4. IMPACT describes the connection with the biological impact of the diffuse substance in the receiving water 3. DELIVERY/TRANSPORT describes the complex journey the solutes, colloids or particles take after mobilisation to connect to the stream (Haygarth et al 2005)

8 UKCIP 2020 Higher year-round temperatures Warmer, wetter winters Hotter, drier summers Increase in intense rainfall events Increase in number of very hot days Precipitation change (%) Mean temperature change (ºC)

9 Effects of climate change on the mobilization of diffuse substances from agricultural systems Macleod C.J.A.(Kit) 1, Falloon P.D. 2, Evans R. 3, and Haygarth P.M. 4 1 North Wyke Research, Okehampton, Devon, UK. 2 Met Office Hadley Centre, Fitzroy Road, Exeter, UK. 3 Anglia Ruskin University, Cambridge, UK. 4 Centre for Sustainable Water Management, Lancaster University, Lancaster, UK.

10 Model farm systems N Upland sheep -altitude -year round -low input Lowland dairy -heavy soils -livestock -manure/slurry Arable -good Q -rotation -PPP

11 Arable Higher year round temperature 3 Detachment Solubilization Increase in number of very hot days ~30 days more Warmer wetter winters 1.0ºC 10% precip Increase in intense rainfall events Up to 75% more Hotter, drier summers

12 Lowland dairy Detachment Solubilization Increase in number of very hot days Higher year round temperature to 1.0ºC days GS Warmer wetter winters 0.5 to 1.0ºC 10% precip Increase in intense rainfall events % increase Hotter, drier summers

13 Upland sheep Higher year round temperature 3 Detachment Solubilization Increase in number of very hot days Increase in intense rainfall events % increase Warmer wetter winters Hotter, drier summers ºC -20% precip ºC 10% precip

14 The challenge of scale...

15 PLOT SCALE Incidental P transfer 7 days after the application of fertilizer and slurry Rainfall (mm hr 1 ) Discharge (L hr 1 ) Slurry Zero P TSP Loads kg ha TP conc (mg L 1 ) Time (hours) (Preedy et al., JEQ, 2002)

16 HEADWATER CATCHMENT SCALE Loss of signal in incidental P transfer at Den Brook? No clear relationship between time of P inputs (fertiliser or slurry) and normalised P loss event -1 ) Norm TP loss (kg mm Time since P application (days)

17 The challenge of multiple sources... Den Brook, Devon: Overflow from silage storage area...

18 Piped discharges of runoff P from multiple sources (Kivernoll, R. Wye) (Withers et al. Journal of Environmental Quality 38 September October 2009)

19 Septic tank impacts on water quality? P load, Chitterne Brook Consented All septic tanks P source apportionment, Chitterne catchment 6% 40% 60% 94% Septic tanks Agriculture ~ 90% of septic tanks are not consented They do pollute water If all septic tanks are considered, less P is attributed to agriculture Septic tank discharges may increase in stream P concentrations by ~ 15µg l 1 Consented STs, only All STs Source: May et al. (2010) Report to Natural England & Broads Authority

20 Stakeholder Workshop to Define best Practice Guidelines 8 th Dec 2009 What form should guidelines for diffuse pollution management take?

21 What form should guidelines take? Published in J. Environ. Qual. 38: (2009).

22 The challenge of producing new guidelines.. Guidelines for whom? Actually diffuse pollution itself is not commonly communicated at the ground level and this has to be the first step we cannot proceed without this? Consensus: We need guidelines on working together and raising awareness! Guidelines for diffuse pollution or environmental issues more generally? Scoping and building new links and partnerships Locally and nationally led Diffuse pollution footprints may help raise awareness Post reductionism, away with the silo Self organized and self learned, locally led solutions

23 To deliver this we need 1. A mapping and targeting of potential communities involved and the opportunities 2. New communication at all levels local training and exploration of the best ways to communicate the issues 3. A national diffuse pollution Campaign (longer term) 4. Need for a high level national level political leadership (longer term) 5. Value add from other initiatives...

24 Eden Catchment Demonstration Centre A focal point for local engagement Organise a local stakeholder events Demonstration events

25 38 staff, 8 organizations Involve as many staff as possible to provide group consensus, rather than to associate few staff in more detail Building a new way of working

26 A Virtual Observatory for Water Soil systems...towards a new science culture Stakeholders and scientists interact a real and virtual way to set the science questions, find solutions... Convergence of data from many sources Community involvement, shared information and experience, meetings virtual and real Emergence and sharing of models, failures and solutions... Continual iteration and improvement... /ha Mitigation Options: 4 Halve P to 3 index and no P to index 4+ intensive grassland 7 Reduce feed P input to dairy 39 Riparian Zones 38 Install farm track sediment traps 36 Move gateways 24 Restrict livestock access in marginal places/times 35 Constructed wetlands/sedimentation ponds 23 Rate of application 22 Timing windows (intensive dairy) kg/ha 23 22

27 ECOSYSTEM GOODS AND SERVICES FOR THE UK (Haygarth and Ritz 2009) Gas regulation Climate regulation Refugia Cognitive Primary production CO 2, CH 4 NO x, N 2 Nutrient cycling Biodiversity Soil formation Water supply Erosion control Heritage Biomaterials Raw materials Food supply Water storage Recreation Water quality Platform Supporting Provisioning Regulating Cultural

28 We must raise national awareness and get the public to own the issues

29 Challenges, Gaps & Opportunities The challenge of scale and complexity, apparent loss of signal due to time lags Multiple sources, septic tanks, P challenge new ways of working with data and models Changing the culture of uncertainty

30 Challenges, Gaps & Opportunities Developing new ways of cross discipline working, communities, networks & communication, training & working together Nurturing societallyowned integrated ecosystem thinking and value Guidanlines for the ways ahead..