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Taw River Improvement Project – Science Day
Funded by Catchment Restoration Fund
Dr Laurence Couldrick Westcountry Rivers Trust
Pressures on our rivers
Pressures on our rivers
Impacts on the river and society
WFD Fish failures
WFD Phosphate failures
REGULATION“Polluter pays”
Cross ComplianceNitrate Vulnerable Zones
INCENTIVES“Provider is paid”
Environmental SchemesPaid Ecosystem ServicesCapital grant payments
WIN-WIN“Provider saves”
Cost-Benefit advice Best Practice farming
Tools for addressing impacts
Taw River Improvement Project
1. Surveying and Monitoring
2. Fisheries management
3. Agricultural management
4. Biodiversity management
1. Surveying and Monitoring
2. Fisheries management
3. Agricultural management
4. Biodiversity management
Solutions
Using Environmental Monitoring To Improve Our Rivers
Dr Naomi Downes-TettmarEnvironmental Monitoring
September 2013
Why do we monitor?
Long term goal is for:‘improved and protected inland and coastal waters’
Monitoring is needed to determine quality and provides a measure of improvement
The Water Framework Directive (WFD) provides an approach to protect and manage the water environment
11
12
The bigger picture
13
What do we monitor?
Classification for surface waters
Routinely carry out chemical and ecological monitoring of the water environment
14
Classification System
15
Ecological monitoringBrings together information on the plants and animals, their interactions, and the environment they live in
Impacts of pressures
Nutrient enrichment?Flows?
Habitat modification?
Organic Pollution?Siltation?
Water Flows?
Nutrient Enrichment?Light limitation /Siltation?
Acidification?
Monitoring at one site in all waterbodies
Triennial rolling programmeDiatoms InvertebratesMacrophytesFish
Phys-chem monitoring on an annual basis
16
Monitoring programme
17
Reasons for Failure (RFF)
If an element is ‘less than good status’ we need to see what action can be taken to improve this to ‘good status’
RFF identify the cause of the problem (activity, source, sector)
Source apportionment
Identify possible solutions
UNCLASSIFIED
10 of 11 waterbodies ‘less than good status’ in 2009
RFF not enough detailRequires investigative monitoring
10 investigations
Greater resolution required to achieve better environmental outcomes
18
Monitoring in the Upper Taw
19
Monitoring in the Upper Taw
Waterbody ID Waterbody Name Class. 2009 Class. 2013 Failing Elements
GB108050008250 Taw (Source to Bullow Brk) Moderate Moderate Fish, Phophate
GB108050008270 Ash Brook Moderate Poor Fish
GB108050008280 Yeo (Lapford) Good Moderate Phosphate
GB108050008290 Knathorne Brook Bad Poor Fish
GB108050013960 Huntacott Water Moderate Moderate Fish, Copper
GB108050013980 Little Dart River Moderate Moderate Fish, Phophate
GB108050013990 Sturcombe River Moderate Moderate Copper
GB108050014170 Bullow Brook Moderate Poor Diatoms, DO, Phoshate
GB108050014340 Little Dart River Moderate Moderate Diatoms, Copper
GB108050014630 Taw (Upper) Moderate Moderate Diatoms, Phoshate
GB108050014650 Dalch Moderate Poor Fish, Diatoms, Phosphate
* Elements responsible for change in status
UNCLASSIFIED
Collecting baseline information on the condition of all water bodies
Greater resolution needed for RFF database
A number of investigations underway
The more information we can collect about the failing elements the better the environmental outcomes will be
20
In conclusion
DATA REVIEW--‐
TURNING DATA INTO INFORMATION
Alan Tappin, Paul Worsfold & Sean Comber
Biogeochemistry Research CentreSoGEEs
Plymouth University
Background
River Taw orthophosphate (mg P L-1)
(Annual mean & std dev)
1990 1995 2000 2005 20100
1
2
3
Bullow Brook
1990 1995 2000 2005 20100.0
0.1
0.2
0.3
0.4
0.5
Newbridge
1990 1995 2000 2005 20100.0
0.1
0.2
0.3
0.4
0.5
Chapelton Footbridge
1990 1995 2000 2005 20100.0
0.1
0.2
0.3
0.4
0.5
Umberleigh
1990 1995 2000 2005 20100.00
0.25
0.50
0.75
1.00
Newnham Bridge
1990 1995 2000 2005 20100.00
0.25
0.50
0.75
1.00
Kersham Bridge
Sticklepath1990-2006
<0.04 mg P L-1
1990 1995 2000 2005 20100.0
0.1
0.2
0.3
0.4
0.5
Rowden Moor
1990 1995 2000 2005 20100
1
2
3
Yeo Farm
1990 1995 2000 2005 20100
1
2
3
Bondleigh
1990 1995 2000 2005 20100
1
2
3
Taw Bridge
1990 1995 2000 2005 20100
1
2
3
Chenson
Taw Valley creamery (1974)
Orthophosphate vs river flow
0 50 100 150 2000.0
0.1
0.2
0.3
0.4
0.5
0 5 10 15 200
1
2
3
4
5
0 50 100 150 2000.0
0.1
0.2
0.3
0.4
0.5
Mean daily river flow (m3 s-1)
Orth
opho
spha
te (m
g P
L-1 )
Taw (Taw Bridge)
Taw (Chapelton Footbridge)
Tamar (Gunnislake)
Orth
opho
spha
te (m
g P
L-1 )
0.00
0.05
0.10
0.15
0.20
0.25
Jan Feb Mar Apr May Jun July Aug Sept Oct Nov Dec0.00
0.05
0.10
0.15
0.20
0.25
0.0
0.5
1.0
1.5
2.0
2.5
Taw (Taw Bridge)
Taw (Chapelton Footbridge)
Tamar (Gunnislake)
Orthophosphate by monthMean & variation
Jul 2
006
Jan
2007
Jul 2
007
Jan
2008
Jul 2
008
Jan
2009
Jul 2
009
Jan
2010
Jul 2
010
Jan
2011
Jul 2
011
Jan
2012
Orth
opho
spha
te (m
g P
/ l)
0.0
0.3
0.6
0.9
1.2
1.5EA measurement Taw BridgeContribution from creameryContribution from N Tawton STW
Orthophosphate at Taw Bridge
Orthophosphate in diffuse inputs
0 30 60 90 120 1500
2
4
6
8
River flow (m3 s-1)
0 3 6 9 12 15
Orth
opho
spha
te lo
ad (g
s-1 )
0
1
2
3
Chapelton Footbridge
r2 = 0.75n = 353p < 0.001
Diffuse PO4 ~ 0.05 mg P L-1
Taw Bridge
r2 = 0.31n = 255p < 0.001
Diffuse PO4 ~ 0.06 mg P L-1
0 10 20 30 40 50 600
1
2
3
4Head Barton (Mole)
r2 = 0.59n = 234p < 0.0001
Diffuse PO4 ~ 0.03 mg P L-1
UKTAG (2012) Site Specific WFD Reactive Phosphorus (~ orthophosphate) standards
1990 1995 2000 2005 20100
50
100
150
200Taw (Chapelton Fbr)
1990 1995 2000 2005 20100
50
100
150
200Taw (Umberleigh)
1990 1995 2000 2005 20100
100
200
300
400
500Taw (Newnham Br)
1990 1995 2000 2005 20100
100
200
300
400
500Taw (Kersham Br)
1990 1995 2000 2005 20100
100
200
300
400
500Taw (Chenson)
1990 1995 2000 2005 20100
200
400
600
800
1000Taw (Taw Bridge)
1990 1995 2000 2005 20100
200
400
600
800
1000Taw (Bondleigh)
1990 1995 2000 2005 20100
200
400
600
800
1000Taw (Yeo Farm)
1990 1995 2000 2005 20100
50
100
150
200
Taw (Rowden Moor)
Medium/Poor boundary (ug L-1)
Good/Medium boundary (ug L-1)
High/Good boundary (ug L-1)
Annual mean orthophosphate (ug L-1)Observed : Predicted concentration ratio
UKTAG (2012) Site Specific WFD Reactive Phosphorus (~ orthophosphate) standards
Medium/Poor boundary (ug L-1)
Good/Medium boundary (ug L -1)
High/Good boundary (ug L-1)
Annual mean orthophosphate (ug L-1)
Observed : Predicted concentration ratio
1990 1995 2000 2005 20100
50
100
150
200Knowl Water (Velator)
1990 1995 2000 2005 20100
50
100
150
200Bradiford Water
(Blakewell)
1990 1995 2000 2005 20100
50
100
150
200Barnstaple Yeo
(Collard Br)
1990 1995 2000 2005 20100
50
100
150
200Dalch (Canns Mill Br)
1990 1995 2000 2005 20100
50
100
150
200
Dalch (u/s Lapford STW)
1990 1995 2000 2005 20100
400
800
1200
1600Dalch (u/s Yeo conf)
1990 1995 2000 2005 20100
100
200
300
400
500
Lapford Yeo (Nymet Br)
1990 1995 2000 2005 20100
100
200
300
400
500Lapford Yeo (Bury Br)
1990 1995 2000 2005 20100
50
100
150
200Lapford Yeo (Bow Br)
1990 1995 2000 2005 20100
200
400
600
800
1000Ash Brook
UKTAG (2012) Site Specific WFD Reactive Phosphorus (~ orthophosphate) standards
Medium/Poor boundary (ug L-1)
Good/Medium boundary (ug L-1)
High/Good boundary (ug L-1)
Annual mean orthophosphate (ug L-1)Observed : Predicted concentration ratio
1990 1995 2000 2005 20100
50
100
150
200Knowl Water (Velator)
1990 1995 2000 2005 20100
50
100
150
200Bradiford Water
(Blakewell)
1990 1995 2000 2005 20100
50
100
150
200Barnstaple Yeo
(Collard Br)
1990 1995 2000 2005 20100
50
100
150
200Dalch (Canns Mill Br)
1990 1995 2000 2005 20100
50
100
150
200
Dalch (u/s Lapford STW)
1990 1995 2000 2005 20100
400
800
1200
1600Dalch (u/s Yeo conf)
1990 1995 2000 2005 20100
100
200
300
400
500
Lapford Yeo (Nymet Br)
1990 1995 2000 2005 20100
100
200
300
400
500Lapford Yeo (Bury Br)
1990 1995 2000 2005 20100
50
100
150
200Lapford Yeo (Bow Br)
1990 1995 2000 2005 20100
200
400
600
800
1000Ash Brook
SummaryOrthophosphate in the Taw catchment
• EA data from 1990 – 2012 examined• Highest concentrations in upper Taw (Yeo Farm to
Chenson)• Large annual variability in concentrations• PO4 vs flow and monthly trends indicate importance of
point sources• Creamery effluent may have accounted for much of the
PO4 at Taw Bridge
• Diffuse PO4 between 30 – 60 µg L-1
• Retrospective fitting of proposed WFD PO4 standards indicate catchment wide failures since 1990
1965 1970 1975 1980 1985 1990 1995 2000 2005 2010 0
100
200
300
400
1965 1970 1975 1980 1985 1990 1995 2000 2005 2010 0
100
200
300
400
Orth
opho
spha
te (u
g/l) weekly data
monthly data
Orthophosphate in the Dorset FromeEast Stoke
Sampling frequency (Taw, Chenson)1990 - 2012
Sampling interval (days)
0 30 60 90 120 150 180
Cum
ulat
ive
frequ
ency
(%)
0
20
40
60
80
100
57 %
Sampling frequency on the TawChenson, 1990 - 2012
WFD CIS Guidance Document 7 (2003)Monitoring under the WFD
Surveillance monitoring [4 – 12 samples / year] is envisaged to answer this question:
What is the percentage change in mean concentration between any 2 years that could be detected with 90 % confidence?
i.e. can you say there is an actual difference between two values and be correct 9 out of 10 times
Percentage change calculation depends on:
• spread of concentration values around annual mean• number of samples collected per year
1970 1980 1990 2000 2010
% c
hang
e
0
10
20
30
40
50 Frome (weekly)Frome (monthly)
Percentage change in theDorset Frome
Percentage change in the Taw
1970 1980 1990 2000 2010
% c
hang
e
0
30
60
90
120
150
180Frome (monthly)Chapelton Fbr (monthly)Taw Bridge (monthly)
SummarySampling in the Taw catchment
• ca 50 % samples collected monthly
• Monthly sampling makes trend detection more difficult
• Upper Taw worse than lower Taw in this respect
Tracing Phosphate Sources
Steve Granger
Taw River Improvement Project
Forms of PhosphorusTRIP Research Partnership
North Wyke
Sub-catchments of the Taw are failing for phosphorus
Particulate P (>0.45µm)
Soluble P (<0.45µm):
Organic
Forms of PhosphorusTRIP Research Partnership
North Wyke
Sub-catchments of the Taw are failing for phosphorus
Particulate P (>0.45µm)
Soluble P (<0.45µm):
Inorganic
Catchment PhosphateTRIP Research Partnership
North Wyke
Soluble P (<0.45µm):• Inorganic PO4
-
River Type
High Good Moderate Poor
µg P l-1
Type 1 30 50 150 500
Type 2 20 40 150 500
Phosphate Concentrations at Taw Bridge
Year90 91 92 93 94 95 96 97 98 99 00 01 02 03 04 05 06 07 08 09 10 11 12 13
Pho
spha
te c
once
ntra
tion
( g P
l-1)
0
200
400
600
800
Phosphate Concentration Cycles
Environment Agency data
Isotope: atoms of a given element that contain the same number of protons in their nuclei but differ in the number of neutrons
Stable isotopes of an element differ in mass, but have essentially identical chemical reactivity
Stable Radioactive
0.02%99.98% Trace
Kinetic fractionation: the extra neutron results in slower reactions
Fry. (2006)
Tracing Phosphate with Stable Isotopes
Using 18O as a tracer for phosphate
There is only one stable isotope of P!
Most P naturally occurs associated with O, and in its inorganic reactive forms it is phosphate (PO4). Might the δ18O of the PO4
- molecule might be used?
However when PO4 is cycled through enzyme-mediated reactions some of the original O becomes exchanged with water O. Over time the δ18OPO4 moves into a predictable equilibrium with δ18OH2O
The P-O bond in PO4- is resistant to inorganic hydrolysis at the
temperature and pH of most natural systems
Therefore in P limited systems any observed variability in δ18OPO4
compared to the expected equilibrium value will either:1. reflect mixing of isotopically distinct sources of PO4
-
2. the alteration of the δ18OPO4 as the result of biological processes
Technique developmentSource values and variability
Fertilizers: France, Mean +21.6‰ (n=9) (Gruau et al., 2005)
STW discharges: USA & France, Mean +13‰ (n=17) (Young et al., 2009).
(Young et al., 2009).
Using 18O as a tracer for phosphate
Taw Bridge
Upper Taw catchment
10km
N
1. Base-flow sampling for PO4 concentration:• Taw main stem from head to Taw
Bridge• Assorted tributaries feeding the
Taw• STW and industrial effluents
2. Three river main stem and 3 tributaries collected for isotopic characterisation
3. STW/effluent samples collected for isotopic characterisation
4. 5 x 5 diffuse source samples collected and characterised throughout the year
TRIP Research Partnership
Using 18O as a tracer for phosphate
Tamburini et al (2010)
• Soil• Fertilizer• Manure
Using 18O as a tracer for phosphate
Taw Marsh3 µg P l-1
Sticklepath4 µg P l-1
Ford Brook5 µg P l-1
March 2013 N
Sticklepath4 µg P l-1 Taw Green
8 µg P l-1
Wickington4 µg P l-1
Newlands8 µg P l-1
Cocktree16 µg P l-1
deBathe36 µg P l-1
March 2013
479
N
327 µg P l-1
Newlands8 µg P l-1
Spires Lake24 µg P l-1
North Tawton33 µg P l-1
Bondleigh32 µg P l-1
Taw Bridge25 µg P l-1
Ashridge9 µg P l-1
BondleighBrook
24 µg P l-1
ClapperBrook
21 µg P l-1
March 2013
3938
N
Taw Marsh4 µg P l-1
Sticklepath4 µg P l-1
Ford Brook11 µg P l-1
June 2013
River Type
High Good Moderate Poor
µg P l-1
Type 1 30 50 150 500
Type 2 20 40 150 500
N
Sticklepath4 µg P l-1 Taw Green
55 µg P l-1
Wickington6 µg P l-1
Newlands53 µg P l-1
Cocktree13 µg P l-1
deBathe105 µg P l-1
June 2013
River Type
High Good Moderate Poor
µg P l-1
Type 1 30 50 150 500
Type 2 20 40 150 500
6298
N
Newlands53 µg P l-1
Spires Lake38 µg P l-1
North Tawton398 µg P l-1
Bondleigh500 µg P l-1
Taw Bridge529 µg P l-1
Ashridge12 µg P l-1
BondleighBrook
73 µg P l-1
ClapperBrook
102 µg P l-1
June 2013
10100
River Type
High Good Moderate Poor
µg P l-1
Type 1 30 50 150 500
Type 2 20 40 150 500
Cheese factory: 231
N
Taw Marsh1 µg P l-1
Sticklepath4 µg P l-1
Ford Brook11 µg P l-1
September 2013
River Type
High Good Moderate Poor
µg P l-1
Type 1 30 50 150 500
Type 2 20 40 150 500
N
Sticklepath4 µg P l-1 Taw Green
68 µg P l-1
Wickington8 µg P l-1
Newlands66 µg P l-1
Cocktree7 µg P l-1
deBathe154 µg P l-1
September 2013
River Type
High Good Moderate Poor
µg P l-1
Type 1 30 50 150 500
Type 2 20 40 150 500
6450
N
Newlands66 µg P l-1
Spires Lake86 µg P l-1
North Tawton1611 µg P l-1
Bondleigh1659 µg P l-1
Taw Bridge2286 µg P l-1
Ashridge10 µg P l-1
BondleighBrook
70 µg P l-1
ClapperBrook
152 µg P l-1
September 2013
9832
River Type
High Good Moderate Poor
µg P l-1
Type 1 30 50 150 500
Type 2 20 40 150 500
Cheese factory: no discharge
N
Initial DataSource values and variability
STW discharges: USA & France, Mean +13‰ (n=17) (Young et al., 2009).
(Young et al., 2009).
Using 18O as a tracer for phosphate
Questions?
Taw River Improvement Project
Assessing sewage spatially – a sensor based approach.
TRIP Science Day, North Wyke Rothamsted Research
Simon BrowningRS Hydro
Water quality multiprobes
• Wide range of sensors integrated into one common platform
• Manta2 ‘sonde’ provides power, automatic cleaning, data logging and data output
Available sensors
• Temperature• Dissolved oxygen• pH • Conductivity• Oxidisation reduction
potential (ORP)• Depth / water level• Turbidity• Chlorophyll a
• Blue-green algae• Ammonium• Nitrate• Rhodamine• Coloured dissolved
organic matter• Tryptophan-like
fluorescence• Optical Brightening
Agents
Polluting organic matter
• Dissolved organic matter (DOM) is a natural and essential part of the ecosystem
• In excess it leads to an explosion in microbial populations as it decays
• This in turn leads to a dangerous drop in oxygen levels and raised levels of ammonium, nitrate and phosphate
Sources of DOM
• In order to address inputs of excessive DOM in a catchment it is necessary to identify them
• Human sources include sewage treatment works, septic tanks and misconnected domestic plumbing
• Non-human sources include silage liquor, slurry and other farm wastes, milk, faecal matter in run off from fields, yards etc.
How sensors can help…
• We can easily measure the impact of polluting DOM using established sensors for dissolved oxygen, ammonium, turbidity, conductivity etc.
• There is a delay in these effects becoming apparent which makes it harder to pinpoint the source in time and space
• We could do with a way of detecting the polluting DOM directly and ideally get an indication of the type of source
Using fluorescence
• Fluorimeters work by emitting light at one wavelength and detecting light emitted by the target at another wavelength
• Only certain substances exhibit this property and at very specific pairs of wavelengths
• This means that fluorescence can be a very selective and sensitive optical technique
The ‘excitation-emission matrix’
Using fluorescence
• Polluting organic matter has been shown to fluoresce at certain pair of wavelengths
• Optical Brightening Agents (OBA) are used in washing powders and other domestic products to make them look whiter or brighter
• The amount of detectable fluorescence depends on the cloudiness or turbidity of the water
Ideal scenario – base flow conditions
Tryptophan Turbidity OBA0
10
20
30
40
50
60
TryptophanTurbidityOBA
Inert suspended sediments only
Tryptophan Turbidity OBA0
10
20
30
40
50
60
TryptophanTurbidityOBA
Polluting DOM from predominantly non-human sources
Tryptophan Turbidity OBA0
10
20
30
40
50
60
TryptophanTurbidityOBA
Polluting DOM from predominantly human sources
Tryptophan Turbidity OBA0
10
20
30
40
50
60
TryptophanTurbidityOBA
Rapid Catchment Assessment- Spatial survey of 3 sub-catchments
- Upper Taw- Dalch-Knathorne-Yeo- Little Dart-Huntacott
- Sonde deployed at all key bridges- Turbidity- Tryptophan- Optical brighteners
- Whole catchment sampled in 1 day
Diatoms – What does biology tell us about the problem
Matthew Dougal
What is a diatom? Uses of diatoms What is the problem? What makes diatoms good bio-indicators? Aims & objectives Methodology Results Conclusions References
Contents
Domain – Eukaryote Kingdom – Chromalveolata Phylum – Heterokontophyta Class – Bacillariophyceae
Microscopic Unique algae; Silicon cell wall Found in almost every environment 10,000 – 12,000 known species
What is a diatom?
Form the basis of many food chains Account for 20-25% of Global O2 Bloom earlier than other algae species During blooms, diatoms get smaller through
reproduction
What is a diatom?
Diatomaceous earth used in swimming pool filters, temperature and sound insulators, dynamite and clarifying beer
Used in determining if the cause of death is drowning in cases found in water
Bio-indicators (most common use)
Uses of diatoms
Fish sightings in the Taw catchment are low in comparison to previous years
Devon is a very agricultural county – large input of phosphorus into water bodies through run-off, cattle etc.
Input of nutrients affects producers of food chains (diatoms) which has a knock-on effect along the food chain
What is the problem?
Early indicators of change due to rapid growth Sensitive to chemical change, yet resistant to
physical processes Cell wall resists decay allowing use of diatom
fossil record One of the most abundant algal species found in
lentic an lotic systems Different species have different tolerances, and
require certain conditions for growth Diatoms are one the most used bio-indicators
under the EU WFD
What makes diatoms good bio-indicators?
To analyse the diatom populations found within the Taw catchment and it’s sub-catchments; Lapford Yeo and Little Dart
To compare and assess diatom populations between summer and winter
Data can be used in conjunction with phosphorus and sediment data to produce a ‘clearer image’ of the Taw and it’s sub-catchments
Aims and objectives
Referred to the method for sampling and analysing by Kelly et al (2001)
5 stones were scrubbed per sampling point, transferring the scrubbings to a phial with 20ml of alcohol for preservation.
Samples were purified using hydrogen peroxide Samples were mounted on to microscope slides with
cover slips Under a microscope, 300 diatom cells were counted Once all the slides had been counted, TDIs (Trophic
Diatom Indices) were calculated which were then used to produce the EQRs
Methodology
Results – Taw catchment
Boundary EQRHigh/good 0.93Good/moderate 0.78Moderate/poor 0.52Poor/bad 0.26
Boundary values when assigning ecological status (Environment Agency, 2012)
There is a notable difference between Sheepfold (0.97) and the other sites (0.56-0.58) in the main Taw catchment.
Results – Lapford Yeo
Boundary values when assigning ecological status (Environment Agency, 2012)
There is a slight difference in EQR’s – particularly when comparing Menchine (0.51) and Calves Bridge (0.59).
Results – Little Dart
Boundary values when assigning ecological status (Environment Agency, 2012)
Unlike the Taw and Lapford Yeo, there isn’t much of a notable difference between sampling sites at Little Dart, except Knowstone Outer Manor (0.72) which is a high moderate score
Results – winter vs. summer
Boundary values when assigning ecological status (Environment Agency, 2012)
Taw followed a similar pattern during both seasons, while the data obtained for Lapford Yeo increases in EQR’s in the winter, while decreasing in the summerWinte
rSummer
Winter Summer
Sheepfold closest sampling site to ‘reference conditions’ Sheepfold only sampling site to achieve ‘good’ ecological
status Other sampling sites in the Taw ranged from low to mid
moderate Both head-waters of the Lapford Yeo and Little Dart did
not score as well as Sheepfold Sampling sites at the Little Dart ranged from mid to high
moderate; sites at Lapford Yeo ranged from poor to low moderate
The EQR score was a gradual decline when moving along the Little Dart (very similar to the pattern in the Taw). Lapford Yeo didn’t follow this pattern
Conclusions
During both seasons, The Ecological Quality Ratios roughly followed the same pattern in the Taw. Data shown by Lapford Yeo was comparatively lower
Lapford Yeo had the lowest scoring EQRs and the highest levels of phosphorus
The average results showed that Menchine failed to reach the moderate boundary, whereas using only site C Yeo Bridge had a ‘poor’ status
Diatoms continue to be a useful bio-indicator to ecosystem health
Conclusions
Bellinger, E.G. & Sigee, D.C., 2010. Freshwater Algae - Identification and Use as Bioindicators. 2nd ed. Oxford: Wiley-Blackwell.
Castro, P. & Huber, M.E., 2010. Marine Biology. 8th ed. McGraw Hill.
Environment Agency, 2012. A streamlined taxonomy for the Trophic Diatom Index. Evidence, pp.1-32.
Feio, M.J., Almdeida, S.F.P., Craverio, S.C. & Calado, A.J., 2009. A comparison between biotic indices and predictive models in stream water quality assessment based on benthic diatom communities. Ecological Indicators , IX, pp.497-507.
Graham, L.E., Graham, J.M. & Wilcox, L.W., 2009. Algae. 2nd ed. San Francisco: Pearson Education.
Hall, R.I. & Smol, J.P., 2010. Diatoms as indicators of lake eutrophication. In J.P. Smol & E.F. Stoermer, eds. The Diatoms: Applications for the Environmental and Earth Sciences. 2nd ed. Cambridge: Cambridge University Press. pp.122-51.
Hein, M., Pedersen, M.F. & Sand-Jensen, K., 1995. Size-dependent nitrogen uptake in micro- and macroalgae. Marine Ecology Progress Series, CXVIII, pp.247-53.
Horton, B.P., 2007. Diatoms and Forensic Science. Paleontological Society Papers, XIII, pp.13-22.
Kelly, M.G. et al., 2001. The Trophic Diatom Index: A User's Manual. Revised Edition. Envrionmental Agency: Technical Report, pp.1-146.
Mann, D.G., 2010. Diatoms. [Online] Available at: http://tolweb.org/Diatoms/21810 [Accessed 06 February 2013].
Round, F.E., 1993. A review and methods for use of epilithic diatoms for detecting and monitoring changes in river water quality. Methods for the Examination of Waters and Associated Materials.
Singh, M., Kulshrestha, P. & Satpathy, D.K., 2004. Synchronous use of maggots and diatoms in decomposed bodies. JIAFM, III(26), pp.121-24.
Sumich, J.L. & Morrissey, J.F., 2004. Introduction to the Biology of Marine Life. 8th ed. London: Jones and Bartlet Publishers, Inc.
Vinebrooke, R.D., 1996. Abiotic and biotic regulation of periphyton in recovering acidified lakes. Journal of the North American Benthological Society , (15), pp.318-31.
Westcountry Rivers Trust, 2013. The Taw River Improvement Project (TRIP). [Online] Available at: http://therrc.co.uk/Bulletin/May2013/CRF_Taw.pdf [Accessed 09 September 2013].
References
www.adas.co.uk
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Sediment tracing: do we know where its coming
from?
Professor Adie Collins
The sediment problem
Linking with the WFD
Survival to hatching
Survival to emergence of
progeny
Influences oxygen supply
Oxygen concentration
[POM and clays degrading oxygen]
Seepage velocity
[Coarse sediment reduces pore space]
SedimentAccumulation
Blocks emergence
[Coarse sediment creates impenetrable seal]
Build up of
ammonia
Gravel Framework
Mobility
Source fingerprinting grass topsoils arable topsoils damaged road verges channel
banks/subsurface sources
Source fingerprinting farm yard manures
and slurries damaged road verges instream decaying
vegetation point sources (STWs /
septic tanks)
TRIP study areas
Pollutant source tracing
Organics analysis shredded material:
TC / TN NIR bulk isotopes 13C,
15N humic substances:
fluorescence SUVA254 TOC
Artificial redd sediment sampling
Basket extractions
February – eyeing stage March – hatching stage April – emergence stage May – late spawning
Preliminary results – River Taw farm yard manures and
slurries 18%
damaged road verges 21%
instream decaying vegetation
42% human septic waste
19%
EYEING STAGE
Preliminary results – River Taw farm yard manures and
slurries 38%
damaged road verges 18%
instream decaying vegetation
34% human septic waste
10%
HATCHING STAGE
Preliminary results – River Dalch farm yard manures and
slurries 21%
damaged road verges 8%
instream decaying vegetation
57% human septic waste
14%
EYEING STAGE
Preliminary results – River Dalch farm yard manures and
slurries 38%
damaged road verges 7%
instream decaying vegetation
47% human septic waste
8%
HATCHING STAGE
Key messages thus far
farm manures and slurries are an important source of sediment-associated organic matter
instream decaying vegetation an important source
evidence for human septic waste contributing to particulate material in spawning areas
Sediment source tracing
provides cross sector data
covers minerogenic and organic components of sediment pollution stress
assists targeting of mitigation measures
provides direct link to point of biological impact
applicable at multiple scales
River sediment quality - how much phosphorus is in our river sediment and how stable is it?
Will Blake, Emily Burns, Sean Comber, Matt Dougal, Rupert Goddard
School of Geography, Earth and Environmental SciencesPlymouth University
Presentation ingredients
2. Study goals and experimental design
3. Spatial patterns in PP concentrations
1. Phosphorus transfer pathways and
processes
Agricultural sources Point sources
4. Geochemical partitioning of PP in river sediment
5. Conclusions
Field sampling Laboratory analysis
Amount of P in river sediment
Stability of P in riversediment
Catchment processes and management framework
Upstream impacts… downstream consequences
Soil erosion in agricultural catchments:downstream sediment-related issues
Aquatic ecosystems:Damage to habitat(freshwater and marine)Reduce light infiltration
Water resources:Reservoir storage capacity and life spanWater quality
Infrastructure:Navigation issuesChannel capacity FloodingSiltation of harbours
Need source-transfer-storage knowledge to support management solutions to meet Water Framework Directive targets
P and sediment in agricultural catchments
ew.govt.nz
• Exported in dissolved and particulate forms (inorganic and organic)
• Particle-associated flux often up to 90% of total (PP)
• Catchment P yields originating from agricultural land are in the range 0.1 – 6 kg P ha−1 (Withers and Jarvie, 2008)
• River fine sediment PP concentrations range from < 400 mg kg-1 (low intensity agriculture) to > 1500 mg kg-1 (high intensity agriculture) (Walling et al., 2000)
Point sources of P and interaction with sediment in the river channel
• River fine sediment PP concentrations range from <400 mg kg-1 (low intensity agriculture) to >1500 mg kg-1 (high intensity agriculture)
• River fine sediment PP concentrations >2500 mg kg-1 in urban systems impacted by CSOs and STWs (Walling et al., 2000)
Sediment and contaminant flux to the coastal zone
www.eosnap.com
Movement of P from terrestrial to aquatic systems
Pierzynski et al. (2000)
Sediment and P storage within river systems – study aims
How much P is held by sediment stores?
Could sediment become a future source of P?
Study aims and approach
Sample analysis
Freeze-dried and homogenised
XRF major and minor element
analysis
Acid digest and TP analysis
ICP-OES
Sequential extraction and P
analysis ICP-OES
Results (1): spatial distribution of silt PP concentration in Taw and subcatchments
Results (1): spatial distribution of silt PP concentration in Taw and subcatchments
Results (1): spatial distribution of silt PP concentration in Taw and subcatchments
Results (2): geochemical partitioning of PP in sediment
• Striking consistency in the distribution of P within sediment across the catchments and concentration range with notable role of Fe
• ‘Available’ component generally < 15%• QC checks showed excellent reproducibility
in extractions and comparability with XRF
Results (2): geochemical partitioning of PP in sediment
• PP hotspots showed greater proportion of P related to Fe, Al and humic substances– At the STW and dairy outlet due to Fe treatment– In the upper Little Dart where natural Fe was higher
Will the channel sediment release stored PP to the water column?
• Compare to experience elsewhere…
• Importance of redox status of longer term downstream sediment sinks ... Influence of biotic processes and bioavailability?
River sediment quality - how much phosphorus is in our river sediment and how stable is it?
Conclusions to date• Phosphorus concentrations in channel sediment
– Concentrations of phosphorus in fine sediment stored within the Taw and tributary river channels is generally well above the ‘baseline’ literature value of < 500 mg kg-1 implying inputs from DWPA
– Concentrations are elevated in the vicinity of known point sources with a spatially-extensive downstream footprint
– Some localised hotspots are more likely to be due to sediment composition and limitations of concentration data must be borne in mind
• Phosphorus geochemical stability– Phosphorus appears to have an affinity for iron within the river sediment– Downstream changes in oxygen status of sediment stores may act to
release P to the water column – The bioavailability of P in the sediment is a key consideration (next talk)
Mitigating offsite impacts of sediment at small and larger catchment scales [e.g.]
Reducing connection between disturbed land and streams and rivers
Restoration of stable natural sediment [plus contaminant] sink zones
Phosphate in sediment --‐ How much is bioavailable?
Emily Burns, Sean Comber, Will Blake, Rupert Goddard
• Why worry about phosphorus in sediment• Why is the bioavailable portion important?• Tests in the Upper Taw• Results• Implications
Outline
• Water Framework Directive requires ‘good ecological quality’ to be achieved (ideally by 2015!)
• Identifies/quantifies expected biodiversity/abundance (diatoms, macrophytes, invertebrates, fish)
• Diatoms – linked to eutrophication – linked to phosphorus (in river waters)
• New P standards (EQS) are very low and suggest we are failing in many rivers
• P enters rivers via farm land & sewage/industrial effluent
• Lots in the sediment• So…..
Why worry?
• How bioavailable is the P in sediment to diatoms etc?• If we reduce P to the river – will the sediment act as a
source of contamination for many years to come?
Objectives
Sturcombe; CreacombeLittle Dart;
Chawleigh
Dalch; Washford Pyne
Taw; North Tawton
Taw; Skaigh Wood
Sediment exchange
Sediment
Water
What happens if we reduce inputs to the river
?
And will that P be bioavailable?
Diffuse Gradient in Thin Films (DGT)
SedimentPorewater
‘Dissolved’ P ‘Bioavailable P’
Ferr
ihyd
roxi
de la
yer
Probes in place
Depth profile of bioavailable P
0 1000 2000 3000 4000 5000 6000 7000-12
-10
-8
-6
-4
-2
0
2
NTWPCHCR
Bioavailable P (µg/L)
Dept
h (c
m)
EQS < 50 µg/l
0 200 400 600 800 1000 1200
-250
-200
-150
-100
-50
0
50
100
150
200
250 NTWPCHCR
Bioavailable P (µg/L)
Eh (m
v)
0 100 200 300 400 500 600 700 800 9000
500
1000
1500
2000
2500
3000
3500
4000
4500
0
500
1000
1500
2000
2500
3000
3500
NT CH CR WP Bioavailable P (µg/L)
Pore
wat
er C
once
ntra
tion
(µg/
L)
Tota
l P (p
pm)
The filled points represent a 5 cm depth, while the hollow outlines of the same shape represent the 15 cm depth for each site.
The porewater markers are solid while the Total P marker are outlines
P linked to calcium
500 1000 1500 2000 2500 3000 3500 4000 45000
2000
4000
6000
8000
10000
12000
14000
16000
18000
f(x) = 3.68761372547994 x − 886.548606071048R² = 0.652785242009339
NT WP CH CR SW
Total P (ppm)
Tota
l Ca
(ppm
)
10 20 30 40 50 60 70 80 90 100 1100
2
4
6
8
10
12
NT WP CH CR SW
DGT P (µg-P/L)
Tota
l Ca
(ppm
)
P influenced by fertilisers?
0
2000
4000
6000
8000
10000
12000
14000
16000
18000
0 1000 2000 3000 4000 5000
Ca (m
g/kg
)
P (mg/kg)
Taw
P linked to calcium
10 20 30 40 50 60 70 80 90 100 1100
2
4
6
8
10
12
NT WP CH CR SW
DGT P (µg-P/L)
Tota
l Ca
(ppm
)
1) The method has shown useful data regarding sediment P chemistry (v complex, v. variable)
2) Current analytical method used to determine ‘Soluble Reactive P’ is likely to be over estimating bioavailable P in water
3) Calcium present in sediment (or overlying water) can ‘lock up’ the P – need to consider sediment chemistry in detail
4) Cattle/animal drinking points particularly bad as fertiliser and direct animal inputs
5) So… there is a lot of phosphorus in the sediment, of which a significant proportion is ‘potentially’ bioavailable, depending on sediment chemistry and redox potential.
Conclusions
Taw River Improvement Project – Science Day
Funded by Catchment Restoration Fund
Dr Laurence Couldrick Westcountry Rivers Trust
