Transcript Slide 1
SCIENCE AND INSTITUTIONS IN EU WATER MANAGEMENT Keith Richards and Feng Mao Objectives The WFD is a legal institution that embodies a range of ideas (themselves informal forms of institution) and is implemented by agencies (formal institutions). This presentation examines contention at each of these institutional levels. It draws on the European experience, and examines the additional contentions that may arise in seeking to introduce ecologically-focused water quality assessment procedures elsewhere; for example, in China. It will consider The scientific challenge of defining typologies and reference conditions The balance between harmonisation (the Common Implementation Strategy) and diversity of approach, and its relationship to scale of implementation The lack of consideration of “interdependence” in aquatic and riparian ecosystems involved in a method that focuses on individual indicators The integration of WFD monitoring procedures into pre-existing monitoring practices (both ecological and chemical) The practical risks associated with a “one-out-all-out” method of quality assessment The application of the DPSIR (Driver-Pressure-State-Impact-Response) model at the catchment scale given a “reach”-scale monitoring procedure Its underlying assumption is that to be explicit about these areas of contention and difficulty can help to improve the WFD and its application. The Water Framework Directive (i) Underlying principles and practice (i) Define water bodies Lakes – but also parts of river networks (But at what resolution? 5, 50, 500km2) Select a common basket of measures Hydromorphological, ecological and chemical indicators Hydromorphology only if it supports good quality How should these be selected, sampled and measured? Use these to define the quality status of water body 6-point scale; High, Good, Moderate, Poor, Bad; and Heavily Modified Are these distinctions on a linear or non-linear scale? The HMWB option provides a political choice The Water Framework Directive (ii) Underlying principles and practice (ii) Make the quality status relative to a reference state The Reference State is essentially “High Quality” But what is the Reference State? (Pre-Bronze Age?) Ensure the Reference State varies with water body type What classification of river types is to be used? Design programme of measures so each water body is of “good” ecological status by 2015 (*in the EU!) How to define scale at which measures are applied? If HMWB, only aim for “good ecological potential” The devil is, as always, in the detail The common WFD process is a set of laudable principles Its practices are contentious and politicised at every step Typologies (i) WFD – Type A and Type B Type A Criteria Altitude Catchment area Classes High: >800m Mid-altitude: 200 to 800m Lowland: <200m Small: 10 to 100 km2 Medium: >100 to 1000 km2 Large: >1000 to 10000 km2 Geology Very Large: >10000 km2 Calcareous Siliceous Organic Type B Criteria Slope (m/m) Classes <=0.005 0.005-0.02 0.02-0.04 >0.04 Hardness/Alkalinity (mg <35 mg CaCO3/l Soft water CaCO3/l) 35-100 mg CaCO3/l Medium hardness >100 mg CaCO3/l Hard water Some ecological relevance, but little connection with hydromorphology Many alternative river typologies Typologies (ii) River Styles™ (Australia) Brierley and Fryirs (2000, 2004) Typologies (iii) Montomery and Buffington (1997) Typologies (iv) A compromise? Combine the “downstream” effect with channel pattern characteristics that determine physical habitats Typology B >0.04 0.02-0.04 0.005-0.02 <=0.005 slope classes (m/m) Channel styles Cascades and bedrock channels Step-pool channels Braided and wandering channels Pool-riffle channels Braided and wandering channels Pool-riffle channels Lowland meandering channels Lowland meandering channels Anastomosing channels Favours measuring channel attributes For example - bed, bank, cross-section properties; and Summing attribute scores, rather than a pass-fail approach Reference Conditions (i) What is the Reference Condition An arbitrary and pragmatic choice (the art of the possible?) At what scale can a Reference Condition be defined? Can there be a “European” Reference Condition? No, because there is not even a single RC in one basin Are RCs defined for each Ecohydrological Region? Common Implementation, or Subsidiarity? Urbanic, G and Podgornik, S (2008) Testing some Europeanfishbased assessment systems using Slovenian fish data from the Ecoregion Alps. Natura Sloveniae 10(2), 47-58 What would this mean, say, for China? Reference Conditions (ii) What good is measuring against a historical state? A river’s water quality is in practice irreversible. It is improbable that a river’s state can be made to recover to an exact historical condition Using a programme of measures to shift the state of a water body from “Moderate” to “High” state would almost inevitably be different from the historic Reference Condition defined for it, because of the dynamic interaction of quality parameters A review on 56 independent studies on freshwater ecosystem in 1910-2008* shows that only 18 have recovered, and even in these cases, it depends on the variables selected Therefore we must avoid unrealistic expectations …and perhaps the historical reference state is unrealistic …but: we do need to have a clear goal. What should it be? * Jones HP, Schmitz OJ (2009) Rapid Recovery of Damaged Ecosystems. PLoS ONE 4(5) Aquatic/Riparian Ecosystem Dynamics Static v dynamic character of ecosystems More attention needed to the dynamics of ecosystems Standard system defines static picture of ecosystem state Insufficient to design water quality monitoring and remediation Aquatic ecosystem dynamics reflect species interactions Need methods that capture this dynamic behaviour Ecological network analysis Well-established method of analysing biological interactions Developed for marine ecosystems, but applied to river ecology* Supported by software developments (eg ECOPATH with ECOSIM) This offers potential *Christensen (1998) J Fish Biol; McCabe & Gotelli (2000) Oecologia Integration into existing monitoring Methods of monitoring Diverse range of methods of monitoring “Bottom-up”, field-based methods “Top-down” desk-based methods (GIS/RS) Preferred methods Reflect existing preferences (if they exist) Reflect scale of problem (GIS/RS may be basis for initial multi-dimensional classification of water bodies and subsequent sampling of water bodies) Field-based methods Difficult to avoid some field methods (aquatic ecology) More acceptable if existing use of field survey Integration into existing monitoring (eg) River Habitat Survey RHS assesses the physical structure of rivers by field survey of c.500m lengths of river. The method has been used in the UK since 1994 (updated in 2003). It was developed partly in anticipation of the WFD monitoring needs. Other countries also use a form of RHS.. Greece, France, Italy. Confidence in the survey data is maintained by consistent data recording by trained surveyors. (WFD hydromorphological survey methods could be designed to build on the RHS.. this would favour a bottom-up, field-based method in countries with RHS-type assessment already) . Typical RHS reach-length survey Environment Agency (2003) River Habitat Survey in Britain and Ireland: Field Survey Guidance Manual, 2003 Version. 74pp Combining metrics (i) The One-Out-All-Out Method Figure 1 Figure 2 Combining metrics(ii) Ineffective/Inefficient Too stringent a water quality standard is ineffective. Inflated type I errors Ineffective distribution of funding; poor water quality does not necessarily receive more funding Administrative Region 1 Lenient Appropriate Stringent Administrative Region 2 A B C D E Good Good Good Good Good Bad Good Bad Bad Bad Bad Bad Good Good Good What alternatives are there? Various methods of combining scores for different attributes Simple average, different decision tree structure Expert judgement (weighted average) A method that explicitly considers interaction of ecosystem elements Applying the D-P-S-I-R method (i) Programmes of measures Implemented if water body status is below “Good” May be developed from use of D-P-S-I-R method – eg… Driver: Fishery habitat management Pressure: River substrate manipulation State: Altered flow regime, deep pools; changed chemistry Impact: Changes to taxonomic composition and productivity of aquatic biota Response: Initiating a programme of substrate reinstatement Drivers that put pressure on river quality status: (For example) Agriculture, Flood defence, Forestry, Navigation, Recreation, Urban development, Water supply and treatment Typical pressures on hydromorphology: River substrate manipulation; bed and bank erosion protection; river channelisation; Flow manipulation Applying the D-P-S-I-R method (ii) Scale at which D-P-S-I-R method is applied Water body remediation may need catchmentscale measures Spatial scale Hydrological regime, sediment supply changes; Environmental adaptation, land use change Catchment Aggradation/incision (sediment wave migration, storage changes); Metapopulation processes Corridor Reach Need full assessment of hydromorphology in order to identify remediation methods Channel pattern dynamics; Patch dynamics, processes affecting age/species/community structure Barform Bar growth & dissection; Local succession processes Bedform Grain Hydraulic roughness; Recruitment processes Time scale (years) Sediment transport; Seed dispersal, woody debris transport 10-1 100 101 102 103+ 104+ Conclusion WFD success Harmonisation Improved water, ecological and river status WFD weaknesses and their resolution Several areas that in detail can be improved Critique and revision desirable Can be developed by continual CIS process Can be built into the 6-yearly cycle