Case Studies - Coastal Lagoons: Ecosystem Processes and Modeling for Sustainable Use and Development - page 449

concluded that phytoplankton production in the Dalyan Lagoon is comparatively
lower than in the other lagoons. It is important to note here that these lagoons have
different hydrodynamic and ecological properties, which affect the response of
primary production to nutrient concentrations.
During the evaluation of water quality, the difficulty usually faced is that there
is no universal limiting nutrient criteria for lagoon systems. The response to nutrient
enrichment and the related changes in ecosystem dynamics that influence the selec-
tion of assessment parameters vary considerably both regionally and among different
types of coastal ecosystems. The U.S. EPA uses a specific regionalized waterbody
type approach to develop nutrient criteria, whereas the European Union makes
regional comparisons of eutrophication status on a common basis; however, these
studies are still ongoing.

9.5.1.1.1.11 Ecological Characteristics
An intensive literature survey conducted to determine ecological characteristics of
the watershed indicates the presence of some endangered and endemic species, which
also has been verified by site visits.
Iris xanthospuria , an iris species peculiar to the region, is spreading in the
aquatic zones, marshes, and Liquidamber orientalis forests. Red pine and L. ori-
entalis are of great importance in the watershed as they are trees endemic to Turkey.
There is an L. orientalis forest of 8 ha northeast of Koycegiz Lake, which is under
protection.
During the long dry period, mosses found at the bottom parts of leafy trees and
pines are important to keep soil moist. The flora of Koycegiz Lake-Dalyan Lagoon
and its surroundings is still being studied. It is estimated that there are about 700
flower plants, needles, and fern species in the region; environmentally important
flora species in the region are Cistus cretius, Colchicum, Cyclamen trochopteran-
thum, Erica, Hyacinthus arientalis, Iris xanthospuria, L. orientalis, Lunipus angus-
tifolius, Nerium oleander, Pinus brutia, Sternbergia eischeriana, and Typha sp. 14
To date, 180 bird species have been observed in the watershed. 15 Holycon
smymensis and Cryle rudis are the two major species. Holycon smymensis is a rare
species of bird and the distribution of C. rudis is limited in Turkey. Their population
is about 100-150 and 250 couples, respectively. The number of species that breed
or have the possibility to breed in the watershed is decreasing.
Iztuzu beach, the nesting and breeding area of Caretta caretta sea turtles, is
among the 17 important sea turtle breeding regions of Turkey. Site surveys have
identified 5 turtles, 2 frogs, 9 snakes, and 12 mammal species. 1
Blue crab, which consume dead fish and similar wastes, thus preventing bad
odor and decay in the environment, is an important species in this sensitive region.

9.5.1.1.2 Socio-Economic Characteristics

9.5.1.1.2.1 Demographical Characteristics
Data gathered from the State Institute of Statistics of the Turkish Republic (SIS)
were used for demographical analyses. According to the 1997 census, the total
population of the watershed area is 43,585, 74% of which lives in the Koycegiz