Background

1. Assessment of POSTER 3 Environmental Impact Living coral reefs in Pulau Semakau KUSU ISLAND PULAU SEMAKAU Debris washed up the shores of Kusu Island Background Kusu Island is located 5.6 km south of the main island of Singapore, off the Straits of Singapore. In 1819, the island was selected as a reference point to guide ships entering the newly formed harbour of Singapore then. Today, landfill and reclamation has joined the original 1.5 ha Kusu Island with another coral outcrop to form a 8.5 ha island resort. Possible Sources of Pollution The main source of pollution on the island is the extremely high level of human activity on the island all year round. This is especially so during the Kusu Pilgrimage Season held during the ninth month of the Chinese Lunar calendar, during which near 100 000 devout Taoist, Buddist and Confucian pilgrims make their way to the island. Associated with the high human traffic is the problem of littering. Littering is a major environmental concern as animals may accidentally mistake and swallow the wrong food, with the worst case scenario being a major food poisoning of the entire food web on the island. Besides, non-biodegradable products like plastic may also contaminate the soil on the island. In addition to land pollution from littering, motor ferries carrying worshippers to and fro the island also contributes to water pollution. This may endanger the marine ecosystem in the waters surrounding Kusu Island, especially Kusu island's coral reefs. Human disasters like houses catching fire from the lighted joss-sticks and candles also pose threats to the wildlife on the island. Background Located south of the main island of Singapore, Pulau Semakau is a partly reclaimed island formed by connecting the previous smaller Pulau Semakau and another small island, Pulau Sakeng, with a 7km rock embarkment. It contains the Semakau Landfill, Singapore's first offshore landfill and the only remaining landfill today. All our wastes go through Singapore's four incinerators and ends up on the island today. However contrary to popular beliefs, this 'garbage dump' is brimming with life and nature. Since July 2005, Pulau Semakau has even been opened to the public for nature-related recreational activities. Possible Sources of Pollution The identified possible sources of pollution on the island are as follows:Semakau Landfill The Semakau Landfill covers an area of 3.5 square kilometres, divided into 11 bays known as 'cells'. During construction, 13 hectares of mangrove groves were destroyed to make space for the landfill. Even though this was subsequently replanted, the initial food web and ecosystem there have been destroyed. Rare animals or plants may have already become extinct before they are discovered. Future dumping of waste on the island in these cells may also leak into surrounding soil and waters, contaminating the environment on the island and destroying the whole ecosystem on the island. These will be a huge blow to the limited flora and fauna in Singapore. Recent Human Activity on the Island Since July 2005, Pulau Semakau has been opened to the public. This was so as to share the beauty of nature with the public and in turn raise awareness in the public about the need to conserve such delicate beauty for future generations and how this very idea is indeed possible. However, the recent human activity may actually hinder efforts to maintain the delicate ecosystem on the island. Increased use of petrol-based jetty to ferry tourists to and fro the island may pollute the nearby waters, harming the coral reefs in the sea. Littering is also a known habit of humans, and this will also result in land pollution of the island. Hence the threat of pollution by this recent increase in human activity is very real. Impacts of Human Development & Conservation Measures taken While sources of pollution have been identified on the island, great care has been taken to prevent these threats from realising. As a CNN report puts it, Pulau Samakau is an "island paradise built on a garbage dump". The 11 individual cells have each been lined with an impermeable membrane and numerous slits to prevent the harmful substances they contain from seeping into the surrounding soil and waters. The replanted mangroves have also thrived extremely well, with some areas having to be cut back. These trees act as a biological indicator and its growth signals that the impermeable walls of the cells have indeed done their job. Regular water testings are also being conducted to ensure the integrity of the slits installed. In a recent survey of the mangroves conducted in 2005, 74 species of plants have been identified , of which 4 are endangered in Singapore. Among them is the Seashore Bat Lily, known to be only recorded in Singapore. There are also vast stretches of seagrass meadows near Pulau Semakau, among which is the Tape seagrass, known to be rare and vulnerable. The island also has thriving coral reefs and rare bird species to be found. Impacts of Human Development on the Island While pollution exist on the island, the environmental impacts are contained. Kusu Island still possess a rich biodiversity, in particular the marine life it supports, with the island ringed by a colourful variety of soft and hard corals. These corals supports vast aquatic life, with clownfish, anemones, shrimps and other rare fish and crabs seldom spotted on other Southern shores. Some of the wildlife found on Pulau Semakau The island’s lagoons and beaches are frequented by tourists, and one major attraction it offers is the fascinating diving experiences or guided reefwalks. One reason behind the flourishing wildlife on the island will probably be the prohibition of overnight camping on the island. By doing so, it limits the amount of human activity on the island each day and allow time for workers to clean up the mess made on the island. Also, as Kusu Island is regarded by many as a sacred place, their respect for their religion and gods temporarily curb their littering habits while they are on the island. Successful education of the public on protecting the environment may also contribute to the success of containing human pollution on the island. SENTOSA Background Sentosa Island, Singapore’s 4th largest offshore island, has an area of 5 square kilometres and lies just half a kilometre away from the southern coast of the main island of Singapore. 70% of the island is covered by secondary rainforest. The island also has a 3.2 kilometre stretch of white sand beach. Significantly large portions of land are currently being added to Sentosa due Sentosa island seashore exposed by the low-tide to land reclamation. Much of the beach lies on reclaimed land which has damaged coral populations. • Possible Sources of Pollution • The identified possible sources of pollution on the island are as follows: • High volume of human and vehicular traffic. • High level of construction activity due to the development of the integrated resort, hotels and residential areas. • Landfill along the coastline.Impact of pollution and human activity on forest ecosystems • The extensive nature of infrastructure development on the island together with the high level and multiple sources of pollution have affected a large part of the original forest ecosystem of Sentosa. The natural flora and fuana of the island has instead been replaced by trees and plants that are selected for their aesthetic reasons than their relations to the original species found on the island. Only a small proportion of the original forest ecosystem remains.Impact of pollution and human activity on aquatic wildlife ecosystems • The shoreline and coast of Sentosa has been substantially altered by landfills and construction activity which has also impacted the aquatic wildlife ecosystem to a large extent. • The construction of marinas and the increased flow of leisure boats within and around the island have also destabilised the aquatic wildlife ecosystem on Sentosa and permanently destroyed many of the coral reefs initially found off the island. Measures to preserve our natural coral reef heritage include: