How to grow a forest: Odisha leads by example

Look at the patch of land on the left above. It's barren, rocky and full of weeds. It's a photograph, taken sometime in 2005, of an abandoned limestone mine owned by Steel Authority of India (SAIL) at Purnapani, some 40km from Rourkela in Odisha. Now look at the picture above right of what seems like a flourishing natural forest, covered thick with several different species of trees. Would you believe that it's a photograph of the same site, taken earlier this year, that is, 12 years from the image on the left?

It's a magical transformation by itself — a natural forest takes hundreds of years to come up — wrought by some cutting-edge biotechnology and the determined efforts of a group of scientists led by CR Babu, professor emeritus at the Centre for Environmental Management of Degraded Ecosystems (CEMDE), a part of Delhi University's School of Environmental Studies, and bankrolled by SAIL and the Central government's Department of Biotechnology.

"This is the first ecological restoration project undertaken on such a scale in India," says Babu, "a model that can be replicated by other mined out areas in the country."

In 2005, the CEMDE team began work on the 250-acre site that constituted an Overburden Dump or OBD of the Purnapani mine, i.e., it was the mound created by the soil dug out of the area that was mined. There was also a water body measuring around 200 acres, formed by water accumulated in voids created by mining activity.

"In an OBD," says Vivek Choudhary, a field biologist, who worked with Babu on the site since 2006 and earned his PhD for his research there, "everything is upside down — the productive layer, also called the top soil, is below, and the unproductive lower mineral zone is above. It is completely barren — nothing grows on it, but weeds. When I first went to Purnapani, the land was full of boulders and the soil was made of hard stone." The lake too was dead.

It's not just the OBD that is thus adversely affected by mining activity, but a far larger area, says Choudhary. "In the monsoon, the water that flows off the OBD carries minerals with it, often containing heavy metals. It leeches into the soil, damaging nearby vegetation and crops and turning the rivers acidic." And so the first challenge was to preserve the topsoil and to do this, the scientists began by planting grass. "Grass can work miracles," says Choudhary. "It grows wherever you plant it, helps retain soil moisture and starts the life cycle by providing organic matter to the soil."

Before that could happen, the scientists mobilised the local communities, especially the women in nearby villages into Self-Help Groups (SHGs). "The idea was to give them a stake in the project. We paid the SHGs to collect native grass and tree species from local forests."

(Purnapani residents sell a variety of mushroom that grows in the forest for Rs 600-700 per kg)

The saplings the locals brought back were planted in a nursery and when they were big enough, re-planted on the site after the weeds were removed. To plant grass, the scientists prepared 'seed balls' — a concoction of soil, cow dung and seeds — which were then scattered all across. The scientists also planted legume species, which helped to increase protein content in the soil. "We did not use any pesticide — only cow dung manure and some inoculants (growth-promoting microbes)," says Choudhary. Into the lake, they introduced plankton, a kind of aquatic micro-organism that is food to fish. "Fish seedlings were then added and today, we get fish between 5-10kg in weight," says Choudhary.

In two years, the entire site was covered in grass, and the scientists then began planting trees, getting the locals to ensure they were not harmed by grazing animals. Only local species were planted — Mahua, sal, palash and fruit-bearing ones like sharifa and several kinds of berries. Also included were species that yield forest produce such as kattha, lac and chironjee. "The idea was to ensure the project was self-sustaining, that along with biodiversity, it gave locals avenues to earn a livelihood. With this in mind, host trees for tussar silk worms were planted and apiaries set up. The forest floor, rich in humus, provides a substratum for a local mushroom, which sells for `600-700 per kg in the local market," says Choudhary.

"Today, the site is a mature sub-tropical, semi-evergreen moist forest that is three-storied (i.e., grass on the forest floor, followed by medium-sized shrubs and tall trees). The average height of the trees is 47ft, with some growing as tall as 65ft," says Babu. The site has about 173 tree species, 50 species of shrubs and herbs, and 50 species of grass. It is also rich in biodiversity, home to nearly 100 species of birds, mammals and reptiles.

"Thousands of hectares of forest ecosystems are degraded because of open cast mining. As much as 0.9 hectares of arable land is being degraded by mining activity every year; if you include forests, the figure will be much higher," says Babu, who was part of the Ministry of Environment's expert committee for coal mining and thermal power projects in the 1990s. The CEMDE, he says, grew out of the recommendations of this committee and was set up in 2001 to help restore abandoned mines and land degraded by mining activity to their natural state. But it's taken 20 years for a Purnapani to happen.

"Ecological restoration is scientifically different from afforestation," says RK Singhal, executive director, SAIL. Popular "tree plantation drives do not result in bringing back a natural ecosystem that existed before mining operations commenced" he says. "On the other hand, ecological restoration leads to the redevelopment of the original natural ecosystem."

What we call afforestation is mostly the planting of a single tree species, often exotic ones like Cassia siamea or Eucalyptus, chosen because they grow fast and grazing animals avoid them, says Dr Sanjit Kumar, divisional forest officer of Rourkela. "Afforestation requires a lot of maintenance and also does not bring about the kind of biodiversity you see in Purnapani. In terms of soil nutrition, ground-water recharge, etc., this is an exemplary model."

No wonder, the success of Purnapani has led to a number of similar projects. CEMDE itself is working on two coal mining sites in Dhanbad and Ranchi. "At the Damada colliery, a dense forest with trees growing up to 20ft has come up in four years," says Babu. But it is at Barka Syal coal field near Ranchi that the CEMDE has notched a bigger success — the ecological restoration of the mine has resulted in extinguishing underground fires in the mines. "Forests were cut down when the mines were set up in these areas. As a result, cracks in the earth were exposed and oxygen could flow underground, fuelling the fires through a process called auto-oxydation. Now that a dense forest has been restored, the oxygen is used by the plants and none of it reaches underground. Also, the roots produce carbon-dioxide, which helps to quench the fire," explains Babu.

Dehradun-based Forest Research Institute (FRI) has been working on a similar project in Tetulmari in the Dhanbad mining belt since 2011, helping restore a 44- hectare site owned by Bharat Coking Coal Ltd (BCCL). The company is also using its learnings from this pilot project to restore nearly 260 hectares of land across all its mines. These are, however, baby steps given the large swathes of mining-degraded land all across the country. What's needed is a wider campaign whether by the government or the mining companies themselves. But are they listening?