Graham Earl & Tom Dargie: Part 1 Interpreting sand dune
habitat change at Sandwich Bay using sequential NVC survey Dr Tom
Dargie Boreas Ecology Sandwich Bay Estate Deal Royal Cinque Ports
Golf Course Bird Observatory Royal St Georges Golf Course Princes
Golf Course Nature Reserve Nature Reserve Google Earth 1.Context:
primary slacks, adjacent effects 2.NVC mapping: 1989, 2001, 2008
3.Changes in habitat extent 4.Directions of habitat change
5.Quadrat analysis of change Himantoglossum hircinicum Lizard
Orchid Ellenberg F = 3 Ellenberg N = 2 Orobanche caryophyllacea
Clove-scented Broomrape Ellenberg F = 3 Ellenberg N = 2 Slide 2 NVC
Mapping: Initial Survey 1989 (Sand Dune Vegetation Survey of Great
Britain) (Doarks, Hedley, Radley & Woolven (1990) NCC CSD
Report No. 1126) Digitised version of 1989 map used in Dargie
(2002) Slide 3 NVC Mapping and Mapping Change: Follow-up Survey
(2001) (T. Dargie (2002) Sandwich Bay Dunes, Kent: NVC Survey 2001.
Unpublished Report to English Nature (Kent Team)) Slide 4 NVC
Mapping and Mapping Change: Third Survey (2008) Royal St Georges
Golf Club (T. Dargie (2009) National Vegetation Classification
(NVC) survey of sand dunes at Sandwich Bay, Kent: 2008 Repeat NVC
Survey of Royal St. Georges Golf Club. Unpublished Report to
Natural England. NE Contract 6/NE/0126) Slide 5 Sandwich Bay
Habitat Extents 1989 - 2001 Slide 6 Royal St Georges GC Habitat
Extents 1989 2001 - 2008 Slide 7 Main Pathways of Change (hectares)
1232520 511511 49 5 9 8 mainly SD8 Festuca rubra - Galium verum
mainly MG1 Arrhenatherum elatius mainly MG12 slack Schedonorus
arundinaceus (Festuca arundinacea) 7 SB 1989 to 2001 RSG 2001 to
2008 1 in cattle grazing enclosure Slide 8 Quadrat Analysis Step 1
Pseudo-random quadrat (pseudoquadrat) approach Rhind et al. (2006)
Proc. Royal Irish Academy 106B first applied it to dune habitat
Simulates species data for 25 quadrats per NVC sub-community based
on (i) Published range in Domin scores (ii) Published constancy
(frequency) class (ranging from I to V) (iii) Published range and
average number of species per quadrat Dr Roy Sanderson (Newcastle)
supplied pseudoquadrat data for dune NVC types Step 2 Ellenberg
Scores Gradient Analysis Calculate F Moisture and N Nitrogen for
pseudoquadrats and RSG quadrats Calculate mean and standard
deviation for F and N per NVC (sub)community Graph probability
ellipses (3 SD widths) for NVC communities on F & N axes Graph
individual quadrat positions, colour coded by year Slide 9
Ellenberg Gradient Analysis: Pseudoquadrat Probability Ellipses
Slide 10 Ellenberg Gradient Analysis: Royal St Georges Golf Course
Quadrats Slide 11 Conclusions GIS evidence suggests that SD8 fixed
dune grassland is changing quite rapidly to MG1 and MG12 Quadrat
change analysis suggests the same (Repeat analysis of target notes
shows the same) The future for key Red Data Book species at this
site seems threatened by hydroecological change Slide 12
Hydro-ecological Investigation of Habitat Change: Based on Sandwich
Bay Sand Dunes, Kent Interpreting sand dune habitat change at
Sandwich Bay using sequential NVC surveys and hydrological analysis
Graham C J Earl Coastal Eco-hydrological Researcher Canterbury
Christ Church University Slide 13 My research is investigating
research recommended in the Dargie (2009) report: The possible
interactions of physicochemical values within the groundwater; The
interactions between vegetation communities and nutrient levels;
The possible influences from golf course management; A possible
long-term increase in the water table, possibly driven by sea-level
rise. The focus of this presentation: The relationship between
hydrological dynamics, physicochemical factors and overlying sand
dune vegetation. Overview of Research Slide 14 Dipwell Positions
Across Sandwich Bay Dipwells chosen using Judgement Quota sampling;
Two tier approach, using historic data and ground truthing;
Locations limited by access and position of water table. Slide 15
Sampling Schematic Dipwell Elevation obtained from LiDAR data,
adjusted to OS Newlyn datum Slide 16 Water samples collected
monthly June 2012 November 2012, with a further collection
quarterly from March 2013 June 2014, and analysed for: Sodium
(NaCl) Potassium (KCl) Total oxidised nitrogen (TON; NO2 + NO3)
Phosphate (P) Ammonia (NH3) pH Electrical conductivity (EC)
Chemical Analysis Slide 17 Observed Total Oxidised Nitrogen
Concentration Summer 2012 Winter 2012 Autumn 2012 Spring 2013 Slide
18 Observed Ammonia Concentration Summer 2012 Autumn 2012 Spring
2013 Winter 2012 Slide 19 Observed Phosphate Concentration Summer
2012 Winter 2012 Autumn 2012 Spring 2013 Slide 20 There is no
significant difference in nutrient concentrations between
vegetation communities; Preliminary results using a nonparametric
Kruskal-Wallis test, on chemical values comparing between different
NVC classes near dipwells; Note: data collection is on going until
June 2014, thus analysis is currently on an incomplete data set.
Null Hypotheses Summer 2012 Phosphate vs. 2012 NVC P = 0.797 Summer
2012 TON vs. 2012 NVC P = 0.055 Summer 2012 NH3 2012 NVC P = 0.456
Summer 2012 KCl vs. 2012 NVC P = 0.032 Summer 2012 NaCl vs. 2012
NVC P = 0.415 Spring 2013 Phosphate vs. 2013 NVC P = 0.537 Spring
2013 TON vs. 2013 NVC P = 0.183 Spring 2013 NH3 vs. 2013 NVC P =
0.539 Summer 2013 KCl vs. 2013 NVC (Not Available) Summer 2013 NaCl
vs. 2013 NVC (Not Available) Summer 2012Summer 2013 NaClP = 0.415P
= 0.623 KClP = 0.032P = 0.213 PO4P = 0.797P = 0.197 TONP = 0.055P =
0.884 NH3P = 0.456P = 0.141 Slide 21 Historic Weather Dynamics and
NVC Communities Surveyed Years Slide 22 Historic Weather Dynamics
and NVC Communities Slide 23 Observed Water Table Levels Autumn
2012 Spring 2013 Summer 2012 Winter 2012 Slide 24 There is no
significant difference between ground elevation and vegetation
community cover; Nonparametric test Kruskal-Wallis, on LiDAR
elevation data comparing between different NVC classes near
dipwells; Adjusted data to ensure samples with 3 replicates were
analysed. Null Hypotheses 2012 NVC Cover P = 0.012 2013 NVC Cover P
= 0.018 2001 NVC Cover P = 0.010 1989 NVC Cover P = 0.038 Slide 25
Data collection on-going (20 months out of a 24 month sample period
has been collected); Only simple non-parametric methods have been
applied so far in data analysis, multivariate analysis will be run
on a complete data set; Repeat survey of tidal fluctuation effects
on the water table height. Summary Slide 26 Funding support: RCPGC
and Natural England; Access permission and other support: RCPGC,
RSGGC, Princes GC, Alan Husk, and Sandwich Bay Residents; Help in
the field in sometimes poor conditions, plus research advice (the
sun does not always shine over Sandwich!): Phil Buckley, Phil
Williams, David Ponsonby, Alex Kent, John Hills (CCCU), Phil
Williams (Natural England), Tom Dargie (Boreas Ecology), Students
at CCCU, Friends and Family. Acknowledgements Slide 27 Thank you
for listening Questions Welcome Contact:
[email protected]
