Mangroves - Wetlands or forests?

Mangrove forest at Pichavaram, Tamil Nadu (Image Source: Shankaran Murugan via Wikimedia Commons,  CC BY-SA 3.0)
Mangrove forest at Pichavaram, Tamil Nadu (Image Source: Shankaran Murugan via Wikimedia Commons, CC BY-SA 3.0)
Listen to this article

Have you noticed short trees or bushes along coastlines with a dense tangle of roots hanging out that makes them look like they are standing on stilts? These are mangroves. Mangroves can be trees, shrubs, ferns and palms that occupy the boundary between the land and the sea. They mainly grow in or adjacent to areas between the high tide and the low tide. They get regularly covered or immersed in water at high tide and exposed to air at low tide.

The roots of mangroves are regularly exposed to saline water. At times, they are also exposed to freshwater surface runoffs and flooding. Mangroves get their nutrition from these tidal saline and freshwater resources and coastal soils and silt that get deposited from the surrounding land after an erosion.

Mangroves not only provide food security and livelihoods to the coastal communities but also provide ecosystem services worth $1.6 billion each year. They provide feeding and breeding grounds for crabs, prawns, mollusks, fish, birds, reptiles and mammals and are important sources of firewood, timber, cattle feed, honey and medicines. They protect groundwater aquifers from mixing with seawater and play an important role in removing coastal pollution due to toxic heavy metals. They also guard against natural calamities like tsunamis, storms and floods.

India  has about 3.3 percent of the global mangrove forest cover. Out of eight states and union territories which support mangroves, West Bengal (2,115 sq. km), Gujarat (1,031 sq. km), Andaman and Nicobar Islands (966 sq. km), Andhra Pradesh (397 sq. km), and Odisha (215 sq. km) have the maximum areas of mangroves.

To know more on mangroves, read frequently asked questions on mangroves here

Mangroves: Are they wetlands or forests?

The degradation of mangroves due to faulty management practices started since the colonial times and continues even today argues this article titled 'An assessment of mangrove management during the colonial and post-colonial periods' published in Current Science.

Mangroves were classified as forests during the colonial times and procedures developed to exploit wood of terrestrial forests were applied to mangroves. For example, mangroves from the east coast of India were brought under intensive management during the late 19th century as products derived from them such as timber, tannin, honey and wax were found to be extremely valuable. This led to extensive degradation of mangrove ecosystems.

However, mangroves are closer to wetlands and should have been classified as wetlands, argues the paper. This is because mangroves fulfill all the three basic conditions of a wetland - they include plants that are adapted to wet soil conditions, mangroves grow in undrained hydric soil, and the soil is saturated or inundated with water at least during the growing period of the plants.

Rapid destruction of mangroves during the colonial times

The first large-scale deforestation of Indian forests by the British started in the late 18th century and continued till the early 19th century, mainly for expansion of agriculture and exploitation of timber and sandalwood for revenue generation.

The second wave of threat to Indian forests came with the advent of railways in the 19th century and the extensive destruction of forests during this time was also realised by the British administration, which led to the advent of scientific forestry.

Scientific forestry implied that more forests had to be brought under the control of the government, seedlings had to be planted in the place of mature trees when removed, cutting of trees had to be avoided before they were fully grown and indiscriminate clearing of forests had to be avoided in the localities around springs from where rivers originated.

As a first step to achieve scientific forestry, the Government Forests Act was passed in 1865, which gave power to authorities to declare any land covered with trees, brushwood and jungle (including mangroves) as a government forest by notification in the Official Gazette. This Act was passed mainly to take over control of timber-rich forests to supply wood to the railways and other public works.

In 1878, the Government Forests Act 1865 was repealed and the Indian Forest Act 1878 was passed. According to this Act, two types of forests were recognised in India: (1) government forests and (2) forests owned by private parties. The government forests were further divided into three types on the basis of access and control over the resources: (i) reserved forests, (ii) village forests and (iii) protected forests. Reserved forests were declared as the absolute property of the government, and people had no rights on produce from the forests.

Forests that had the potential to be declared as reserved forests were declared as protected forests and while rights of local communities on forest produce were recognised, complicated processes were put in place, which became very difficult for ordinary people to follow and assert their rights. The village forests remained inoperative for various reasons.

Use of forests for economic gains and considering them as a commodity became common during the colonial times. Thus forest economy became the central concept in forestry science. Concepts of silviculture that included manipulating forests for economic gains began to be applied in forestry science.

Thus, vast stretches of mangroves in Sunderbans and the Godavari and Krishna districts were cleared for agriculture. Sundarbans mangrove forests were divided into four blocks namely Bagerhat, Khulna, Satkhira and 24-Parganas. Of these, the first three were declared as reserved forests in 1879 and the 24-Parganas block was declared as a protected forest in 1878 according to the Indian Forest Act, 1878.

Similarly, mangroves in the Godavari and Krishna districts of the Northern Circars of the Madras Presidency were notified as reserved forests between 1886 and 1890. Though the mangroves of the west coast of India was explored, none of them were brought under government control.

Mangroves during post colonial times

The same practices followed during the colonial times in forest and mangrove management continued in the post-colonial period, particularly regarding state ownership, denial of access to the forest resources by the local people and forest economics.

Forests continued to be viewed as economic assets and controlled by the state and very little importance was given to the role and rights of local people in maintaining forests. The focus continued on silviculture that involved tree felling during the post-colonial period.

This felling of large sections of mangroves led to evaporation of soil water, which led to subsidence (sinking) of sediments (a common occurrence in wetland ecosystems when they get exposed to prolonged solar radiation) and created areas of shallow troughs.

These areas were referred to as saline blanks during the colonial and post-colonial period and their restoration presented many challenges. Large saline blanks created by felling of mangroves still exist in all the major mangroves of India and their restoration through joint mangrove management approach needs urgent attention, argues the paper.