When we speak of environment protection in Kerala, we make our heaviest investment in or give our utmost attention to the conservation of river banks. Here, let me introduce Dr P. K. Shaji, a scientist who has participated in numerous environment protection programmes and has nearly 40 years of experience in this field. He has a very clear idea about the trees and plants of Kerala and has rich, practical experience in projects designed to reclaim our native ecosystems. Let us also find out from him how to rectify the mistakes we have committed while trying to protect river banks.

For instance, bamboo plants are allowed to grow everywhere in Kerala. From our first-hand experience of conserving the banks of the Vamanapuram river near Venjarammoodu on an experimental-basis, we saw clumps of bamboo, that had been raised along its banks for many years, topple during the floods in the recent years, taking the soil of two and three cents of land with them. The problem is a severe one but our immediate response to the issue of river bank conservation is planting of bamboo plants. Let us listen to Dr Shaji who will tell us how to go about it in a scientific manner. It is under his supervision that we have taken up the project of river bank conservation.

M. R. Hari: Sir, it is from our experience at the Vamanapuram riverside that we learnt how grave the problem is. I have seen bamboo being used to protect river banks at various places. Many people come to me asking for bamboo saplings to plant close to rivers. I never knew, until very recently, that it would become such a huge problem. Many scientists told us that planting bamboos to conserve river banks is not very scientific. But, first of all, what do we mean by forest? Does it extend from the tops of hills right up to the sea shore, and also stand on both banks of rivers?

Dr P. K. Shaji: Yes. That is the way it should be perceived. In the past, most of the land was covered by forests. They got destroyed due to various reasons. But protecting riparian vegetation or forests is as good as protecting the rivers. In most places, the practice these days is to build stone walls. We used to do it earlier too but that was done in order to create bathing ghats. If we erect stone walls to protect the entire length of a river, it will no longer be a river! In my opinion, what is needed is to grow native species, completely excluding the foreign species.

M. R. Hari: Sir, what you’re saying is that in places where we do not build stone walls, the river side will be a downward incline with different species of trees growing at different levels.

Dr P. K. Shaji: Yes, here if you look at it, you will see the profile. At the very top you will have the huge trees, followed by medium-sized trees, subtrees and finally the shrubs. Among the big trees, think of the white murdah; in the next level, we can have the freshwater mangrove.

M. R. Hari: Sir, which types of trees grow on the river side?

Dr P. K. Shaji: As I said, the white murdah.  You can also have the wild mango.

M. R. Hari: What about the mahua, sir?

Dr P. K. Shaji: No, the mahua is a smaller tree. Freshwater mangrove and willow-leaved water croton are also suitable. These come under the category of ‘amphibian vegetation’. They grow where land and water meet. Therefore, choose trees that will not wilt when the water level increases, and can withstand frequent changes in water level.

M. R. Hari: Sir, will the burflower tree come in this category?

Dr P. K. Shaji: Yes. Its names in Malayalam – aattu-kadamba/neer-kadamba – themselves indicate this peculiarity. Also the three-leaved caper. Among creepers and climbers, we have the devil's backbone.

M. R. Hari: At Vengarammoodu, we saw what is locally known as incha [Acacia caesia wild]. It is used to scrub the body while bathing . . .

Dr P. K. Shaji: Yes, it is found in many places. But too many numbers can affect the growth of the other trees.

M. R. Hari: Do you subscribe to the view that bamboo should not be cultivated at all on river banks?

Dr P. K. Shaji: No. I spoke earlier about the sloping surface near the river. We have the concept of the ‘gallery forest’ . . .

M. R. Hari: . . . where trees will stand at various levels, as in a gallery.

Dr P. K. Shaji: Yes. There are bamboo thickets, of the elephant grass variety, grown specifically to prevent soil erosion, and help in the conservation of the river bank. There are other varieties too that can be planted for the same purpose. It is when we plant bamboo all over the place that problems begin to crop up.

M. R. Hari: Here, we saw only bamboos being planted, especially the yellow-stemmed one. But all of them got uprooted.

Dr P. K. Shaji: The yellow bamboo is actually a member of the foreign species.

M. R. Hari: Our native one is the solid bamboo variety, which is green-stemmed?

Dr P. K. Shaji: Yes.

M. R. Hari: The elephant grass has broad, green leaves, and grows luxuriantly on river banks. Despite heavy floods, it has not budged.

Dr P. K. Shaji: It belongs to the family of bamboo. Its botanical name is Ochlandra travancorica, and is an endemic plant. It protects slopes very well.

M. R. Hari: . . . and is the staple of elephants. It is when this variety is not available that elephants go in search of other items. In mid-Travancore region, especially in Thiruvalla and Kottayam regions, we see the Malabar tamarind growing by the sides of rivers.

Dr P. K. Shaji: Not in the high altitudes but slightly towards the lower side. But they can also be planted.

M. R. Hari: There is a specific reason for remembering this fact. During my school days, during the floods, the boats in which small children went to pluck tamarind fruits would capsize invariably. There used to be at least one death every two years, caused either while taking the boat or while fishing. Back in the past, tamarind was cheap. But today we get good money for it. It is used for making medicines.

Dr P. K. Shaji: Then, there are a couple of varieties of the Ceylon olive, all of which are endemic, and grow by the riverside.

M. R. Hari: There is the marking nut tree, which causes itching on touch, and that too grows on banks.

Dr P. K. Shaji: Yes.  That too grows on river banks.

M. R. Hari: The white murdah, the three-leaved caper, the fish poison tree, the Portia tree, the mastwood tree and others.

Dr P. K. Shaji: These species appear near the coastal zone.

M. R. Hari: That is, they cannot be found on riversides near the mountains but rather in the coastal areas.

Dr P. K. Shaji: That is why I said, if you look at the point from where the river begins and go right up to where the river touches the sea, the slope of the ground, the alluvial content, the width of the river and other factors change. The plant species composition in these places also changes accordingly. Similarly, certain species found in the altitudes will be different from those found downstream. Sometimes you will even find some varieties slide down the river and form colonies. Yet if we examine the three zones, we will detect three different varieties. Therefore, reconstruction of river banks should be modified accordingly.

M. R. Hari: Going by your calculation, sir, can you tell us how many species of trees and plants grow by the riversides in Kerala?

Dr P. K. Shaji: A definite number may be hard to get because such a study has not been done. Yet we might have at least 30 different species. When we look into the Venjarammoodu project, I feel that we should consider the zonation, and intermix at least 30 habitat-specific species of trees and shrubs near the river. All this will be towards the water line. Behind them, towards the land, we can plant plants like the mootapalam.

M. R. Hari: Isn’t the mootapalam a shrub?

Dr P. K. Shaji: No, it is a tree, though a small one.

M. R. Hari: I’ve seen it grow close to ten feet only, at the TGBRI.

Dr P. K. Shaji: We can consider them as medium-sized trees. Then there is the Lindley’s aporosa. There is something I forgot to tell you earlier. Among the riparian trees and plants, many are endemic. The wild jack, for instance, is an endemic tree although it does not grow near water bodies.

M. R. Hari: We have the wild jack here.

Dr P. K. Shaji: I mentioned it only as an example of an endemic species.

M. R. Hari: Let me rephrase your point, sir. Although this is a hill, this actually descends towards a river, that flows about 300 feet from here. Maybe that is why the wild jack grows here.

Dr P. K. Shaji: But the wild jack usually grows at a greater elevation. What I meant to say is that the wild jack is seen only in the Western Ghats. Many other trees, like the Malabar humboldtia belong to endemic varieties. Such trees have to be preserved. Some of them come under the rare and endangered list. For instance, the white dammar, which grows near the river.

M. R. Hari: I think that tree was planted in Thiruvananthapuram by the British. I’ve seen in in the Trivandrum Club compound and guest house premises, but not in other public places. That is a huge tree, almost 100 years old.

Dr P. K. Shaji: The freshwater mangrove can also be found in front of the Trivandrum Club building.

M. R. Hari: There is a three-leaved caper tree on the road that leads down from the Kuravankonam junction. It has been there for a long time. After Madhavikutty published Neermathalam Pootha Kaalam [When the three-leaved caper bloomed], a Punjabi teacher whom I met at Hyderabad asked me about the peculiarity of the tree. I admitted I did not know but guessed that it must be the fragrance. This three-leaved caper was standing here all the while, and I had passed by it several times. I came to know about it only when Rajasekharan sir of the TGBRI identified it a couple of years back. After that, I saw it bloom.

Dr P. K. Shaji: It looks very beautiful when in bloom.

M. R. Hari: I  have planted it here but it has not started flowering yet. I believe the white murdah is used for making medicines.

Dr P. K. Shaji: It is grown on a commercial basis in places like Maharashtra. Just as the silkworm is fed on mulberry leaves in order to make silk, they are fed on white murdah in order t0 make Tussar silk. The white murdah grows well near river banks.

M. R. Hari: Certain other trees grow on high ground as well, like the strychnine tree. Then there are trees, like the wild jack, that grows near river banks too. Does that happen by accident?

Dr P. K. Shaji: No.  As I said earlier, it grows in the hinterlands as well. The white murdah grows near the river and in the hinterland too. We observe this natural kind of distribution if we examine riverside zones.

M. R. Hari: For the sake of conservation of river banks, we may have to erect walls in certain areas. But in certain other areas, can’t we retain the sloping surface, plant trees in a terraced fashion, and thus protect the riverside, sir?

Dr P. K. Shaji: Definitely. At certain places, we may have to put up walls. I am not against them totally. But we should ensure that walls are not constructed along the entire length. There will be spots where we may not be able to retain the slope. In such cases, wall is the only option. But there should be vegetation too in the region. Secondly, we have soft engineering models. That involves driving bamboo into the ground to make terraces, using coir cloth as cover, and growing elephant grass. As they grow, the area will stabilize itself. Such options can be thought of.

M. R. Hari: Sir, we left out the case of the screw pine.

Dr P. K. Shaji: Yes, the screw pine can be grown at the water line. Have you noticed, sir, that the screw pine has stilt roots which gives the plant the ability to withstand the force of water?

M. R. Hari: We have the bandicoot berry shrub too. When its roots appear, they are soft and red in colour. Later they become hard and grow sideways, piercing even through these dry rocky surfaces.

Dr P. K. Shaji: It is known as Leea indica.

M. R. Hari: I noticed the shrub only after coming here when Dr Mathew Dan pointed it out to me. That is the plant which attracts the most number of butterflies and other flies here, until other plants sprouted.

Dr P. K. Shaji: When we take care of riparian vegetation in this manner, many creatures also get protected, as you mentioned, many butterflies, dragonflies, and bigger creatures like otters.

M. R. Hari: That reminds me of a story. In 1984, there was a strong agitation by environmentalists against the destruction of mangroves at Kumarakom, and I was one of its convenors. Ajith Namboodiri, who is the Vice President of the Bar Association, from Kottayam was another. Both of us were not scientists but members of the Shastra Sahitya Parishad [People’s Science Movement of Kerala]. When all the scientists were brought to the meeting, Sivadas sir of CMS College narrated a story. There was a bird-watcher in Kottayam named Dr Sreekumar who said that when otters caught most of the fish of a region, the local residents killed all the otters. As a result the number of fish also decreased. The reason was that otters could never catch very healthy fish. They killed and ate the feeble ones. So it was discovered that otters played a major role in bringing down the number of unhealthy fish. In a similar fashion, the kingfisher too . . .

Dr P. K. Shaji: Yes, kingfisher, white-breasted waterhen and even migratory birds depend on it. This is a unique ecosystem. Even when it is terribly hot, we can see many creatures colonize this area. That is because they get a secure ecosystem. Food is available. The environment encourages breeding. This also acts like a corridor, permitting movement.

M. R. Hari: When plants and trees stand in water, fish get a place to lay their eggs and remain protected.

Dr P. K. Shaji: Even marine fish make upward migration for the sake of breeding. So the network of roots creates a favourable environment.

M. R. Hari: Some time back, studies about the Thannermukkam bund revealed a story. When the bund was opened, a certain species of prawns was caught. I cannot recall exactly whether they were moving towards the sea or in the opposite direction. They laid their eggs and were about to swim away. But just then, the bund is closed, and they were caught. This practice caused their numbers to dwindle. I think those prawns were called Macrobrachium.

Dr P. K. Shaji: Yes. When dams are built for irrigation purposes, they obstruct the upward migration of such creatures. Therefore, in many places, though not in ours, the concept of the ‘fish ladder’ is put into practice. That is, a series of water-filled buckets is placed, allowing the fish to migrate upwards. It is now stipulated that the fish ladder  should be made whenever dams are built. That is because their breeding takes place only in fresh water. So, all this arrangement is to make sure their migration is not affected.

M. R. Hari: Sir, there is a financial angle to this too. If we build walls to protect all the rivers of Kerala, there is a possibility of their collapse. When people do extensive sand mining, these walls will lose their foundation. This is happening all over Kerala.

Dr P. K. Shaji: When all the sand is mined, it destroys the river itself. However, it is possible to conduct sand auditing and make arrangements to take as much sand as possible. But I don’t know whether they can be implemented in a viable manner. At Venjarammoodu, I noticed that the river meanders.

M. R. Hari: It is very deep there. The barge pole cannot touch the river bed anymore because of sand mining.

Dr P. K. Shaji: There are sand ridges too there. The other day, a friend of mine was suggesting that we carve out sand as it is plentiful there. The sand only needs to be washed before being used, he said, adding that business will thrive. I replied, ‘Yes, the business will thrive and you will grow prosperous. But that will spell the death of the river’.

M. R. Hari: Don’t take that person every again to the area. If we are able to retain those ridges, trees can be planted to prevent soil erosion. But another problem is: where do we find these trees now?

Dr P. K. Shaji: If we conduct a survey, we will certainly be able to find out remains of such natural vegetation. The first step is to identify and protect them. The second is to plant trees in places where we find gaps. When that is done, the seeds will have to be gathered or the saplings prepared in nurseries. That will be a mega project requiring community participation.

M. R. Hari: Many people will listen to what we say. The next step is to acquire 50-100 saplings and plant them on the sand ridges. If each of the plants is introduced to the people, they will participate actively in this project. The main problem they face is lack of correct information. If a person like you are ready to show the different plants, point out their positive and negative features, that will be fine. For instance, some plants like the screw pine have thorns. But many people have jobs in connection with it. Similarly, the Malabar tamarind fetches good price in the markets now. You can show pe0ple where to plant them, or give a demonstration of how to prepare a gallery with 50 plants. Maybe in an episode running to a maximum of 50 minutes. Or spread your content over two or three episodes.

Dr P. K. Shaji: Of course, we can do it.

M. R. Hari: It can be done in three steps. First we should prepare the saplings. The rains will come in June. But at least for the next year, if many of us can work hard for six months and plant trees on river banks, we will be able to preserve them. As far as I understand, the majority of people are not against Nature. There are a few who want to destroy everything in order to make things look neat and clean. But most people wish to promote conservation. However, it has not been possible to give them the required information.

Dr P. K. Shaji: Once they understand the concepts, they will come forward.

M. R. Hari: So let us try it next time. One more thing, sir. Another problem that the rivers face is that of pollution. People throw waste materials into the river. If there is vegetation that will stop the waste from flowing downstream . . .

Dr P. K. Shaji: But the ecosystem will definitely be affected. That is why I said if we can ensure community participation, people will become guardians of rivers. Soon they will stop doing such things.

M. R. Hari: There is a great project going on at Maravanthuruthu. The local people are cleaning the entire area. The river and the river side are being cleaned under a project called STREET (Sustainable, Tangible, Responsible, Experiential, Ethnic, Tourist hubs) as an initiative of the Responsible Tourism Mission. It is possible to have plant vegetation at such places. That is also a river side. A few people are brought into the project, and it is undertaken as part of tourism. One more point. The greenery you see behind this place is a Miyawaki forest that is two years old. The other one is three years old. This one is six months old. All the trees belong to endemic varieties. The time now is 1.55 pm. But we are able to sit here in open air because of all these trees. If we had sat inside a room or veranda, we would have had to switch on a fan. In the past, when I had nothing particular to do, I would go fishing. It did not matter if I did not catch any fish.  I could see the sights around me – the river flow, the squirrel scamper – I could wet my feet in the water or perhaps even pluck mangoes from the tree near the river. Let us hope we can convert these environment-related nostalgic memories into the reality of the present. If people show interest, it will be possible to make this project successful along at least a couple of kilometres of the river’s length.

Dr P. K. Shaji: We should conserve river banks with their endemic vegetation, and preserve biodiversity. In this manner, we will be able to bring back a lot of plants and trees that urgently need protection. Simultaneously, we will be able to bring down atmospheric temperature and carbon levels, take care of oxygen replenishment and harness other environmental benefits.  

M. R. Hari: Riparian vegetation has a big role to play in the sustenance of rivers and streams, and prevent them from drying up.

Dr P. K. Shaji: When community participation is taken care of, and every segment is properly mapped, we will be able to scientifically ascertain the extent of soil erosion. Such a project will also ensure that solutions to the problems are implemented. In this manner, others can be made to understand their duty towards preserving our environment, and be informed about the concept of carbon sequestration. One tree is considered equivalent to ten children.

M. R. Hari: Indeed. Sir, please identify for us the trees and plants that are best suited for the conservation of river banks. The earlier the better. Let us all do it together.

Dr P. K. Shaji: Certainly. We have a team here. So that is possible. Even during the worst floods, the willow-leaved water croton did not get destroyed.

M. R. Hari: Sir, I went to Odisha after a great storm had passed. I did not see a single burflower tree, jack tree or mango tree uprooted there. What went down was the teak tree. All the invasive varieties got destroyed. So, thank you, sir. See you soon.