MAJOR THREATS TO MANGROVE FORESTS IN PAKISTAN

Along the coast of tropic and sub-tropics, the evergreen forests, mangroves are located. Mangrove forests cover an estimated area of 137,760 km2 in 118 countries around the world. Their widespread distribution is due to their ability to cope and survive in harsh environmental conditions. These include variability in temperature, salinity, humidity, and frequent tidal patterns. 

In Pakistan, mangrove forests cover an area of almost 0.6 million hectares and these are distributed along the coast of Sindh and Baluchistan.Mostly concentrated near Sindh coastline and considered to be one of the largest mangrove forests in the world. 

Eight species of mangroves have been reported in Pakistan. But now, only four are present and among these species, the Avicennia marina is dominated covering about 95% of the mangrove forest area. 

Subsequently, many ecological benefits are being provided by the mangrove forests to the neighboring coastal communities. These forests also sustain the ecosystem of the aquatic environment. Mangrove forests are a major source of a variety of products that are useful in daily life operations. These provide us with food, medicine and wood which can be used as a fuel. 

Mangroves also are a great habitat for fishes and aids income generation from fisheries. The mangroves are infrastructures that protect from extreme climatological events like floods and storms.

Despite their utmost importance, mangrove forests are being threatened by different exogenous factors, mostly climate change and their conservation are necessary for environmental sustainability. 

We have majorly lost the mangrove diversity and now it is important to sustain the present forest cover. According to the IUCN report, a major decline has been observed in the mangrove population i.e. 35% of the mangrove forests are lost all over the world. 

Climate change events are becoming a threat to the survival and sustainability of mangroves and these need to adapt themselves quickly to survive. Climate change events include sea-level rise, stronger winds, storms, temperature variability, changing rainfall trends, and strong wave currents.

The association of these events with mangrove forest mortality and disturbances in natural processes has been discussed in several studies. A study conducted in 1995 explained that mangrove forests are majorly threatened by a sea-level rise that is occurring due to changing climate. 

Mangrove forests require a stable level of seawater for their proper growth but an increase in greenhouse gases is causing a rise in the earth’s global temperature which in turn accelerating sea-level rise and its impacts on mangrove forests. 

Overexploitation, overharvesting, and cutting of mangroves for obtaining different products, has also promoted a decline in the mangrove forest cover. Mostly wood, that is either for using it as a fuel or for selling purposes. 

Mangroves are also cleared for making spaces for developing new infrastructures, industrial settlements, aquaculture, and agricultural purposes. 

Mangroves thrive in brackish water and in high salinity their growth is affected. Thus, the change in river flow or storage of water in dams and reservoirs reduces the amount of fresh water reaching the mangroves which increases the salinity of the surrounding water and thus the growth of mangroves gets declined.

Another major driver for mangrove destruction is uncontrolled pollution in the coastal water of Pakistan. Technological advancements and increased population have resulted in an increased amount of waste production. 

A large number of fertilizers and pesticides are used for producing more agricultural output and this leads to agricultural runoff in the rivers. Finally, the contaminants reaching the sea cause coastal water pollution. 

Apart from this, industrial waste also causes severe pollution in the coastal environment. Some of these contaminants include heavy metals and pesticides, have been reported for causing bioaccumulation in the leaves and stems of mangroves.

The continuous decline in mangrove cover has been observed in the earlier 20th century. Mangroves are an important asset in terms of environmental sustainability, species diversity, and economic value. Thus, their conservation is a major concern for avoiding issues that may occur if this ecosystem is destroyed. 

The conservation and management of mangrove forests are controlled by three major organizations including the Sindh Forest Department, Port Qasim Authority, and Board of Revenue. The mangrove forests are categorized as “Protected Forests” under the management of these organizations. 

Almost 55,000 hectares of mangroves have been restored since 2010. In addition to that, a mangrove resource base has also been established by the provincial and federal governments for the restoration of mangrove abundance. Recently ‘2020 Mangroves Plantation Campaign’ has been launched for the restoration of the “Green Coastal belt”

Author: Areesha Muntaha 

Karachi University Pakistan.