Student: Vincenzo Iannuzziello ID : 000815098

GEOG1029 Individual Project Report

STUDY AREA: SANDWICH AND PEGWELL BAY, KENT

A critique of the group project, including a consideration of alternative approaches

The aim of the project is to plan the creation of complexes of ponds providing additional

wetland habitat in order to support wildlife’s and flora’s natural colonisation and habitat

adaptation within Sandwich Bay Special Area of Conservation (SAC) and neighbouring

areas, including the Pegwell Bay Country Park.

Looking at the objectives listed in our proposal I suppose that we have fulfilled (even though

not entirely in the content) all of them:

1. To select potential locations following recommended criteria – by building a model with

ModelBuilder in ArcMap for the identification of potential suitable areas according to our

purpose.

2. To investigate the accessibility and visibility of the short-listed areas – by ground

validation and adopting, to the area chosen as suitable location, two methodologies of

visibility analysis (Line of Sight and Viewshed). However the visibility analysis was carried

out on one single final location chosen only.

3. To model the ponds’ structure following recommended criteria – by designing the structure

of our ponds (3D modeling with AutoCAD 2015).

4. To compile the pond creation action plan and habitat development regulations – by

providing specifications about criteria of pond location/creation and management/monitoring.

We also followed the initially proposed methodology according to the criteria defined in our

proposal. In general, the result of our work approximately met the initial expectations. After

running the model we had our study area significantly restricted in terms of square meters,

facilitating our mission on the field by reducing the areas to visit for ground validation and

points recording. However, the greatest limitation was the Land Cover 2007 which we added

into the model to identify improved and rough grassland and exclude all other areas. In fact,

in some of the identified areas the land use has changed since 2007 as we found agricultural

fields rather than grassland during the field survey.

Overall, the activity at Sandwich Bay was intense and, even if not well coordinated actions

were taken from the beginning by our group, the result was quite satisfactory. However, in

my opinion we could have produced more work (both GIS and CAD) and do more field

activity. To save time and use it to develop more results I would have split our group into two

smaller groups of two people each and organized the activities as follow in the timetable

(next page).

PRESUMED TIME TABLE

09:00 – 12:00 14:00 – 18:00 19:00 – 23:00

Fieldsurvey

GIS/CADwork

Fieldsurvey

GIS/CADwork

GIS achievedresult

CADachieved

result

Monday (day 1)

Group 1(points

recordingPegwell)

Group 2(BuildingModel)

Group 2(points

recordingSandwich)

Group 1(BuildingModel)

Potentialareas

identifiedX

Tuesday(day 2)

Group 1&2(ground

validation)X

Group 1&2(ground

validation)X

Locationschosen

X

Wednesday(day 3)

Group 1&2(tracking

ponds'boundary)

X

Group 1&2(tracking

ponds'boundary)

XWorking on

visibilityanalysis

Working on3D

Modeling

Thursday(day 4)

XGroup 1&2(visibilityanalysis)

XGroup 1&2

(3Dmodelling)

Line of Sightand Viewshed

analysis

3D Model ofthe ponds

Friday(day 5)

XWorking onPresentation

X Presentation X X

On day 1, Group 1 would have been doing some field survey in Pegwell Bay, where the

ground is hillier. The points recorded in Pegwell Bay were useful to compare, with those

recorded in Sandwich Bay, the Lidar's elevation accuracy with the GPS elevation, as we

showed during our presentation, even though there was a mistake in the Sandwich field graph

image (the correct graphs in figures below).

LIDAR VS GPS ELEVATION

In my opinion, on day 1 we should have prioritised our work on the identification of

potential areas by concentrating majority of our efforts building the model (possibly using

more recent sources), as soon as possible, in order to reduce the study area and start our field

activity. To obtain a more recent and reliable result, I would have georeferenced the Habitat

Map 2012 (we received it from Kent & Medway Biological Records Centre) and digitized the

improved grassland areas only (figure below).

The new model would look like (figure below)

At that point, after converted to raster and reclassified, I would have added that layer to the

Weighted Overlay function rather than the reclassified Land Cover 2007 layer. The result

would have been quite different, as the model would have excluded all those areas in the

North-West of the map and in the Centre (Figures below).

REPLACED LAYER`

FLOW DIAGRAM: IDENTIFICATION OF POTENTIAL AREAS

Thus, as the new model indicates that the identified areas are mostly located in the South

(figure above), we could have focused our efforts there and spent more time on the field,

surveying those areas. I would keep the slope layer and the rest of the layers added into the

model with the same parameters, applying the same buffer as we did during the fieldcourse:

• Proximity_to_Populated_Areas - 350m buffer to buildings.shp, in order to consider

only those areas at least 350m from buildings. In India, facultative ponds are situated

no less than 450 meters away from vast populated areas, and in USA 0.5-1Km of

minimum distance is recommended (Shrivastava 2004).

We chose 350m because there are not large residential areas within our study area, but

still we wanted to keep our presumed pond/s far from buildings (even small

complexes of houses).

• Proximity_to_Railway - 50m buffer to railway.shp, in order to consider only those

areas at least 50m away from railways. Proximity to railways should not be injurious

to our presumed pond/s, however we decided to include a safe distance at least to

keep lower the annoying noise of transiting trains.

• Proximity_to_Main_Roads - 650m buffer to main_roads.shp, in order to consider only

those areas at least 650m away from main roads. According to an article published on

internet (Nature et Progrès), ponds should be situated at a minimum distance of 500m

from main roads and must be free from air pollution, industrial fumes, chemical

substances and pesticides.

• Proximity_to_Surface_Water – 30m buffer to surface_water.shp, in order to consider

only those areas at least 30m from surface water.

• Proximity_to_Tidal_Water – 30m buffer to tidal_water.shp, in order to consider only

those areas at least 30m away from tidal water.

As we did not find any scientific reason to allocate our pond at a specific distance

from other water sources (we knew that it should not be linked to any other water

source, but not minimum distance from them are specified), based on our knowledge

we assumed that a distance of 30 metres would be enough to eliminate any water

contamination.

However I would change the range of the values within each layer. The new classes would

get values from 0 to 7 rather than 0 to 5 (during the process we added two more layers into

the model without increasing the values' range according to the number of layers).

The new layers would get the following values (table below):

LAYER NAME WEIGHT CLASSESNEW SCALE

VALUE

1IMPROVED

GRASSLAND22%

IMROVED GRASSLAND

OTHER

NO DATA

7

0

NO DATA

2 SLOPE 13%

0 – 2 (degrees)

2 – 5 (degrees)

> 5 (degrees)

NO DATA

7

5

0

NO DATA

3PROXIMITY TO

POPULATED AREAS13%

ALL

NO DATA

0

7

4PROXIMITY TO

RAILWAY13%

ALL

NO DATA

0

7

5PROXIMITY TO MAIN

ROADS13%

ALL

NO DATA

0

7

6PROXIMITY TO

SURFACE WATER13%

ALL

NO DATA

0

7

7PROXIMITY TO TIDAL

WATER13%

ALL

NO DATA

0

7

With the reclassify function, in the layers which the buffer was applied to, all classes get 0 as

value and NO DATA gets the highest score, meaning that the model will exclude all those

areas where data exist (including the specific buffer distance given). Thus, the model will

show up only those areas where data do not exist, in order to eliminate the chance to get the

potential areas result within populated areas, railways, main roads, surface water, tidal water

(and within the distance specified by the buffer given). The final result will obviously be the

combination of all the layers according to the weight percentage given to each of them.

After building and running the model I would have then exported the output layer of our

potential areas into Google Earth (by converting the shape file in KML), or georeferenced a

Google Earth image in order to more easily localise our destination on the field (figure

below).

On day 2, I would have recorded one point on each potential area, if possible (it is a surface

of about 150 ha), in order to eventually exclude any non-potential area by ground validation

(we were allowed by the land owner to eventually survey the entire private property). I would

have split the group into two parts again, so two of us could survey on the East side of the

CHOSEN LOCATION

OUR CHOSEN LOCATION LOOKS LIKE AN AGRICULTURAL LAND EVEN ON A GOOGLE EARTH IMAGE 2013

railway and two on the West (if we could access here somehow). In this way we could collect

much more data and choose our location among a wider range of potential areas (perhaps we

could indicate more than one location for our project as we planned in our proposal).

Excluding then by ground validation all those areas in which the land use has changed again

since 2012 we would have had all the areas in which we could potentially operate carrying

out our project.

On day 3, after choosing the most suitable locations (possibly the easiest ones for us to reach

the days to follow) we could have tracked the ponds' boundaries on the field with GPS. With

the points recorded we could have now started the 3D modeling of our ponds with AutoCAD

(exporting the shape files into CAD by DWG conversion) and the visibility analysis for each

of them, before and after creating a barrier of 2m. This analysis is very useful to determine

the visibility of an object or area from observer points. Building a barrier to eliminate

visibility can help protect the habitat from human impact and predators, as we showed in our

presentation (figures below).

VISIBILITY

LINE OF SIGHT – NO BARRIER LINE OF SIGHT – WITH BARRIER

FLOW DIAGRAM: LINE OF SIGHT METHOD

FLOW DIAGRAM: VIEWSHED METHOD

VIEWSHED – NO BARRIER VIEWSHED – WITH BARRIER

During day 4 Group 1 would have been completing the visibility analysis for each area with

ArcMap and the 3D modeling of our ponds with AutoCAD. In the meanwhile Group 2 would

have started thinking about the theory part to insert into the presentation (rationale

background, aims and objectives, action plan), refine our work and preparing the results'

layouts. Finally, the day 5 would have been dedicated to the preparation of the presentation

(assembling all the results together and summarizing all our work).

With well coordinated actions we could have saved a lot of time and spent it (in addition to

producing more work) to give more quality to our work, as for example with the 3D

modeling and rendering of our ponds. In order to create very gently sloping margins (as

established in our proposal and action plan) the maximum profundity given to our small and

large ponds are respectively 1.20m and 2.40m, with intervals of inclination of 5 and 10

degrees (figures below).

3D MODELING

SKETCH WITH DIMENSIONS

RENDERING

Generally during the whole project, we have not encountered particular technical difficulties,

except:

- during the construction of the barrier surrounding our ponds (we had to learn how to give

elevation to it by making several attempts);

- and with the Slope layer, when we had some issues creating the mosaic of the Lidar 1m

DTM's tiles covering our whole study area (the process in ArcMap took very long time),

therefore we decided to proceed using the Terrain 5m DTM.

Fortunately, we managed to use the Lidar 1m DTM to carry out the visibility analysis as the

portion of area analysed did not require assemble many tiles into mosaic (with the 1m DTM

the result is definitely more sensible).

The only real obstacle that we encountered was perhaps ourselves, as it was the first time we

worked together in a group (in my opinion we were not completely able to divide the tasks in

order to achieve an optimal result). As a result, we spent the first two days aimlessly walking

around to identify potential locations before completing and running the model that allowed

the identification of them. Working in a group, with different ideas (and especially without a

team leader), could delay the necessary actions to be taken and influence the results (even

though combining diverse skills). However, the awareness matured in this sense could help us

next time to better organize and coordinate our work as a team.

REFERENCES

A. K. Shrivastava (2004) Pollution Development, Environment and Health

Nature et progrès certification: (http://www.saltworks.us/salt_info/si_organic_info.asp)

DATA SOURCES

Mastermap of Sandwich Bay and Pegwell Bay Country Park – (Digimap)

Habitat Map 2012 - (Kent & Medway Biological Records Centre)

Vector district maps and other shapefiles - (Open data – Ordinance Survey)

Terrain 5m DTM - (Digimap)

Lidar 1m DTM – (Geomatics-group)

Aerial photography (Google Earth)