1. BIO2418 – Behaviour and biodiversity 2: North Cyprus
Research project April 24, 2014
How does human
disturbance affect
plant diversity in an
intertidal
environment?
Introduction
The world’s beaches provide habitats for a
diverse array of species (1) that are usually
adapted specifically for that environment. As
such they are often unique in their morphology
and physiology (1). Beaches also provide many
important ecosystem services including;
buffering against extreme events (e.g.
tsunamis); water filtration; nutrient recycling;
nesting sites for marine turtles and seabirds; and
recreational and aesthetic value for use in the
tourism industry (1). Unfortunately, despite, or
perhaps because of their value, they are very
often exploited, over-used and under a variety
of stressors from human activity. These include
destructive cleaning, ‘nutrient depositing’,
harvesting of flora and fauna, mining, pollution
and recreation (1). It is the effects of the latter
two stressors that we will be focussing on in this
study.
Golden Beach, in the Karpaz region of North
Cyprus is a very popular tourist destination, and
consequently tourist accommodation has been
built on its fringes. However, these buildings do
not have planning permission. The hotels have
built wooden gangplanks running from the
accommodation down onto the beach to enable
tourist access. It is possible that these
gangplanks have either directly or indirectly
(through increased human traffic) affected the
floral diversity in the surrounding areas. Around
these gangplanks, and near the edge of the
beach, there is also a large amount of rubbish
that has been left by tourists and locals as well
as washed up on the shore from the
Mediterranean Sea. This inorganic waste is also
likely to have affected the plant diversity or
abundance in some way.
Aims & Hypotheses
In this study we aim to investigate the effects of
human disturbance and the presence of
inorganic waste on plant diversity in an intertidal
environment. We predict that the presence of
inorganic waste will cause reduced plant
diversity and that diversity will differ between
sites where gangplanks are present and where
they are not. We predict that diversity will
increase with increasing distance from the
gangplanks. It is possible that the area with an
intermediate level of disturbance will have the
highest diversity due to the removal of
dominant species (2).

2. BIO2418 – Behaviour and biodiversity 2: North Cyprus
Research project April 24, 2014
Methods
The study was conducted at Golden Beach, in
the Karpaz peninsula, North Cyprus (35.64,
34.54) over two dry and sunny days in April
2014. Three study sites (gradients) were used.
S1 was a gangplank with high levels of human
traffic, S2 a gangplank with low levels of human
traffic, and S3 was a control gradient
approximately halfway between S1 and S2.
Figure 1 describes the layout of each study site
and the quadrat placement. Within each
quadrat, the abundance and percentage cover
of each species of plant and the percentage
cover of ‘rubbish’ (inorganic waste, including
metals and plastics) was recorded.
Shannon’s diversity index was calculated for
each quadrat, and linear regressions were
plotted for diversity against distance from the
gradient for each site and for diversity against
the percentage cover of rubbish. A Kruskal-
Wallis rank sum test was used to test for
significant differences in diversity between sites.
Results
5m
10m
2m2
Figure 1 - Layout of each study site
The approximate peak of the sand dunes was
marked as a starting point for the gradient,
and transects were conducted at 10m
intervals, perpendicular to and on both sides
of the gradient from 0m to 30m inclusively.
2m2
quadrats were conducted at 5m intervals
from 0m to 20m inclusively along each
transect.

3. BIO2418 – Behaviour and biodiversity 2: North Cyprus
Research project April 24, 2014
Contrary to our expectations, at S1 diversity
decreased with increasing distance from the
gradient (as shown in figure 2a). A linear
regression showed a significant decrease in
diversity with increasing distance (F=5.21,38,
n=40, p=0.028). However, the multiple R-
squared value shows that only 12% of our data
can be explained by this model. In contrast, as
shown in figure 2b, at S2, there was a significant
increase in diversity with increasing distance
from the gradient (F=131,38, n=40,p=<0.001).
Again, however, the multiple R-squared value is
low with just 26% of the data being explained by
the model. As expected, at the control site (S3)
there is no significant change in diversity with
increasing distance (F=1.91,38, n=40,p=0.18) as
can be seen in figure 2c.
There were also marked differences between
the diversity indices at different sites. S1 had an
average H value of 0.35, S2 of 0.68 and S3 of
0.38. These values are significantly different
from each other (Kruskal Wallis rank sum test, χ2
= 9.6, n=3, p=0.0084.)
There was a significant negative relationship
between H and the percentage cover of rubbish
in a quadrat (linear regression, F=6.21,118, n=120,
p=0.014.) However, the multiple r-squared value
is markedly low, with only 5% of the data being
explained by the model.
Discussion
Figure 3a – Quadrat from Site 2 showing high levels
of dumped inorganic waste.
The large, intact pieces of rubbish nearer the fringes of the beach
took up larger proportions of the quadrat (had a higher
percentage cover) but the plants did not seem to be particularly
affected by this type of rubbish, and seemed able to recover
quickly. Intertidal organisms are known for being adaptable and
quick to recover after disturbance due to the unpredictability of
their habitat (1).

4. BIO2418 – Behaviour and biodiversity 2: North Cyprus
Research project April 24, 2014
In general, our findings support the prediction
that inorganic waste would have a negative
effect on plant diversity. However, it appears
that the effects of human disturbance on plant
diversity are not as simple.
The results of the regression indicate that, as
percentage cover of rubbish increases, the plant
diversity decreases. However, as there is so
much noise (up to 95%) the results may not be
generalizable or applicable. This may partly be
due to the way in which different types of
rubbish affected the plants in different ways
(see figure 3a and 3b).
The results indicate that disturbance affected
diversity in different ways in different sites.
Diversity was highest at S2, were there was an
intermediate level of disturbance. This is
possibly explained by the intermediate
disturbance hypothesis that states that a small
amount of regular disturbance will remove the
dominant species from a habitat and thus allow
other species to flourish, increasing diversity (2).
In future, studies should be undertaken to
investigate the different responses by plants to
the different types of rubbish, as well as
analysing the more subtle effects, such as
changes to microclimate, chemical pollution and
changes in community composition. A better
analysis of the effects of human traffic should
also be undertaken, particularly during the
summer when sea turtles use the beach for
laying their eggs.
It is likely that, regardless of the presence of
hotels, the beach will be heavily used by visitors.
If this is the case, the aim should not be to
remove the current establishments but to
improve observation, regulation and education
at Golden Beach and similar areas of
environmental importance.
References
1) Omar Defeo, Anton McLachlan, David S.
Schoeman, Thomas A. Schlacher, Jenifer
Dugan, Alan Jones, Mariano Lastra, and
Felicita Scapini. "Threats to sandy beach
ecosystems: a review." Estuarine,
Coastal and Shelf Science 81, no. 1
(2009): 1-12.
2) Joseph H. Connell, “Diversity in tropical
rain forests and coral reefs.” Science,
199, (1978): 199-1302.
Figure 3b – Quadrat from Site 3 showing high levels
of washed up inorganic waste.
In contrast to the rubbish displayed in Figure 3a, the smaller
pieces of rubbish that had washed up were more diffuse in the
habitat and covered a larger area of the beach. This seemed to
have a more negative effect on the plant life. This may be due to
higher levels of chemical pollution in this part of the beach, and
not due to the visible surface waste.