Dr Prasanna Jogdeo, a marine biotechnologist, first learnt about duckweeds whilst pursuing his grasp’s stage from the College of East Anglia within the United Kingdom again in 2009–10.
“As part of the direction, we have been intended to do a six-month analysis venture. I selected to do a venture with Professor Keith Waldron on the Institute of Meals Analysis (IFR), Norwich. The venture was once titled ‘Starch Optimisation in Lemna minor’, a species of duckweed. Upon studying about duckweed, I understood its magic, possible for wastewater remedy and as a protein complement. Duckweed was once one thing which hooked me directly to the topic of phytoremediation,” says Jogdeo, talking to The Higher India.
However what’s phytoremediation? In line with the Nature magazine, it refers back to the “use of crops and related soil microbes to cut back the concentrations or poisonous results of contaminants within the surroundings.” In duckweeds, which glide on or simply underneath the skin of nonetheless or slow-moving our bodies of freshwater and wetlands, he discovered a nature-based answer for the rising requirement of wastewater remedy and rejuvenation of loss of life water our bodies.
Following his grasp’s, Dr Jogdeo got here again to his local Pune as a lecturer on the famend Fergusson Faculty in 2010. Right here, he met his pupil Pooja Tendulkar and presented her to the duckweeds. Their shared fascination with duckweeds brought on a few collaborative tasks in Pune and intensive analysis on how they may be able to be used for wastewater remedy.
In 2013, Prasanna went to Nanyang Technological College (NTU), Singapore to pursue his PhD. In spite of spending the following 4 years operating against his PhD, the collaborative paintings and discussions with Pooja persevered, and shortly the speculation of Lemnion took delivery.
This collaboration ultimately resulted within the advent of a startup in 2018 known as Lemnion Inexperienced Answers. The title ‘Lemnion’ comes from a circle of relatives of duckweed known as Lemnnaceae.
“We began the corporate according to our shared fascination for duckweed and its possible for wastewater remedy. On the other hand, we went forward and bought extra publicity. After we went past simply wastewater remedy and into the ecological rejuvenation of water our bodies, we realised that duckweed was once just a section, albeit vital, of the method,” explains Jogdeo.
Lately, the Pune-based startup supplies a spread of products and services together with ecological rejuvenation of water our bodies (rivers, nullahs, ponds) and organic methods to regard wastewater.
Lemnion works with each companies and governments, and has finished about 30 tasks which come with ecological rejuvenation of centered stretches of nullahs and rivers starting from 100 m to two,000 m, and organic methods to regard wastewater of capacities starting from 1 KLD [kilolitres per day] to three,000 KLD throughout more than one geographies, in particular in Maharashtra.
Using duckweed
“Use of duckweed will also be some of the many interventions hired within the rejuvenation of water our bodies. Ecological rejuvenation is a holistic and multidisciplinary procedure,” says Tendulkar.
Duckweed is a wonderful phytoremediator (crops that uptake vitamins from wastewater). It’s the smallest angiosperm, which grows/floats at the floor of the water and accumulates vitamins throughout the roots. It additionally grows in reality speedy, doubling its biomass in 48 to 96 hours. Additionally they collect vitamins from wastewater and convert them into protein. “Duckweed comprises as much as 40% protein, a composition very similar to that of soybeans,” she provides.
“When hired for remedy of wastewater, the device is designed with sufficient retention time (roughly 4 days) of water for environment friendly remedy, and duckweed is inoculated within the device. As duckweed covers all the water floor within the device, round 75% will also be got rid of each different week after use, and hired as manure for the lawn,” says Dr Jogdeo.
The place do they supply duckweed from? In most cases, duckweed is sourced from native herbal water our bodies.
“Out of a complete of 37 species discovered international, about 4 or 5 are present in India. As soon as bought from the surroundings, we get ready natural cultures of the to be had species and use them. There are some species that display in reality speedy enlargement however are much less tough; some which might be very good phytoremediators and collect a large number of protein; some which might be used as polishers,” he explains.
To handle the issues of wastewater and polluted water our bodies, on the other hand, Lemnion doesn’t rely on one particular form of device or fastened parameters. They supply answers according to a “confirmed toolkit” which will also be configured for particular circumstances.
“Elementary ideas inquisitive about such paintings come with water glide law, nutrient steadiness, stepped forward biodiversity and stakeholder participation. For wastewater remedy, the generation concerned is phytoremediation the place particular phytoremediat-ing crops with particular microbial cultures are hired for high-quality wastewater remedy. Along with duckweeds, we additionally use canna, taro, sedges and grasses like vetiver and pampas,” explains Dr Jogdeo.
Rejuvenating a water frame
The primary primary ecological rejuvenation venture Lemnion labored on was once the Kamandalu river positioned in Sangli district, Maharashtra. Situated at the banks of this river is a village known as Kavathe Mahankal which has a inhabitants of about 25,000. From making plans to execution, it took seven months ranging from March 2022.
“After we noticed the river for the primary time and spoke to village citizens, they didn’t know that the river even had a reputation. They idea it was once only a flow and referred to it as an odha in Marathi. Citizens had little wisdom of the river’s ancient significance and non secular importance. In line with folklore, a shepherd discovered an idol of Goddess Mahankali within the mattress of this river. Therefore, the village was once named Kavathe Mahankal. The river, which was once wholesome, had turn out to be a small and not noted flow through the years,” says Jogdeo.
This venture was once organised in partnership with a tender baby-kisser, Rohit Patil, son of the elected MLA from the Tasgaon-Kavathe Mahankal Meeting constituency.
Those have been probably the most demanding situations Lemnion encountered:
1) There are 9 to 10 temples alongside the river. Waste from non secular rituals was once one large problem together with vegetation and different sorts of choices.
2) Forged waste was once a large downside as neatly. Other people stored throwing plastics, wrappers, and mattresses, and the Lemnion staff even discovered used condoms within the river. Forged waste was once dumped into the river and sewage was once discharged from the village, leading to a polluted river.
3) Human encroachment was once any other fear. Part the width of the river was once transformed right into a highway. Prior to the encroachment, the river was once about 150–180 ft extensive, of which part have been encroached upon. Additionally, because of the erosion of surrounding land, silt deposition larger. General, the water-carrying capability of the river reduced.
To execute the venture, lots of the monetary contributions got here from native non-profit organisations just like the RR Patil Dnyan Prabodhini and Agrani Rurban Building Basis. And the excavation equipment for the rejuvenation venture got here from the Naam Basis.
Right here’s a temporary abstract of the venture: “Forged waste, gathered silt and unbounded enlargement of Typha (tall reedy marsh crops) have been got rid of from the river, and water was once in the end visual. To beef up the standard of this water, it can be crucial to regard the sewage getting into the river. For this, herbal methods have been set as much as deal with roughly six to 8 lakh litres of sewage on a daily basis. It lowered foul odour and stopped mosquito breeding,” explains Jogdeo.
“More than a few indigenous/local timber have been planted to stabilise the banks and save you soil erosion. Stone pitching and coir lining have been achieved to stabilise the banks. Additionally, bunds and instream constructions have been constructed within the riverbed for water glide law. Constructions of free boulders have been created as required. On account of this paintings, the river began turning into wholesome once more,” he provides.
Round 250 scholars and 100 villagers contributed to this venture. About 60 staff got employment for 3 to 4 months because of this venture. Lately, the river is alive. Aquatic existence, together with fish, crabs and different aquatic crops have come again. Birds too began coming again.
“Structural paintings took about 4 or 5 months which integrated a blank up of the forged waste and excavation of the deposited sludge. After we paintings on such streams, we don’t remove the sludge. We use the sludge within the river itself to stabilise the banks. This sludge could be very fertile and we use that at the banks, do coir lining on it and expand plantations,” explains Dr Jogdeo.
“For any river ecosystem, the water glide must be regulated and desires excellent riparian plants (which we in most cases see alongside rivers in its herbal shape). This riparian plants is helping in protecting the soil, mitigating floods, and so forth. There are lots of ecosystem purposes connected to riparian plants. Our primary goal was once to get the ones ecosystem purposes again,” says Tendulkar.
What particular function did duckweed play on this venture? Duckweed has a large number of benefits and drawbacks as neatly, in keeping with Jogdeo. One of the crucial greatest disadvantages is that it covers the skin of the water very speedy, and thus its use must be limited.
“After we are doing one thing in a limited house, it’s higher to make use of duckweed. The most productive factor about duckweed is even though it covers the skin of the water, it does no longer bog down daylight penetration. In most cases, duckweed is falsely in comparison to water hyacinths, which might be very unfavourable to aquatic ecosystems. On the other hand, fish can swim throughout the duckweed. Duckweed additionally doubles up as excellent feed for fish because it produces a large number of protein. Duckweed accumulates all of the vitamins from the wastewater and produces protein for marine existence,” he explains.
Alongside a large stretch of the river, there have been about 5 bridges. Between two of the bridges, Lemnion confined that house for duckweed use.
“On this venture, duckweed performed the function of treating the wastewater or bettering the water high quality. Since we do all of the paintings in summer season, the water glide is much less. Since lots of the rivers in Central India are monsoon fed, there’s much less water within the river. Lots of the water flowing throughout the river was once wastewater coming from within reach villages. That water needed to be handled. Duckweed performed the function of phytoremediation or treating that wastewater,” explains Tendulkar.
Any other key facet of ecological rejuvenation, on the other hand, contains behavioural exchange and consciousness amongst native stakeholders.
“Up to now 4 years, we now have learnt that until you get these kind of stakeholders on board, we can not have a sustainable rejuvenation venture. That makes a large number of distinction in any venture if you have beef up from native other folks. That’s what took place in Kavathe Mahankal. After finishing the venture, the village celebrated the Navratri competition. On that day, a temple within the house sees about 8,000 to ten,000 vacationers pay their respects to the native deity. That’s after we noticed the behavioural exchange we would have liked. We noticed temple folks preventing vacationers from throwing rubbish within the river. They felt a renewed sense of belonging with the river,” he says.
“Via cutting edge tactics and sustainable practices, Lemnion effectively reworked a once-polluted waterway right into a thriving ecosystem. “This river rejuvenation venture serves as a shining instance of environmental stewardship, inspiring us all to offer protection to and repair our treasured herbal sources,” says Rohit RR Patil.
Wastewater remedy
The primary wastewater remedy venture Lemnion labored on was once a duckweed-based wastewater remedy device for a bungalow in Wanwadi, Pune. The capability of the device was once 7,500 litres according to day. Lemnion did the designing and supervision all over execution. The implementation of this venture took virtually a month. “Essentially the most difficult section was once suitable plumbing since this was once our first venture, to make sure environment friendly remedy,” recollects Tendulkar.
For treating wastewater, the bottom line is the law of water glide and retention time required for remedy. The roots of those crops [specific phytoremediat-ing plants] penetrate into the herbal media (gravel, stones, and so forth). The roots with biofilms on them penetrate throughout the herbal media, following which the water passes via. Those biofilms do the paintings of having the vitamins from the water and shifting them to the plant for his or her enlargement.
Some other folks name this procedure the built wetland device (or terrestrial device). Very similar to herbal wetlands, built wetlands additionally act as a biofilter and/or can take away a spread of pollution.
“We even have an aquatic device, the place we use duckweed. Water comes into one tank. At the floor of the tank, we now have duckweed rising. Since duckweed grows at the floor, we now have fish in it so the flow of water and vitamins assists in keeping taking place. Right here, the water glide is regulated. Relying at the high quality of the water, we offer sufficient retention time for the water to get handled. In opposition to the top, the water is pumped and used for gardening,” explains Jogdeo.
The aquatic device has duckweed rising at the floor. The wetland device has herbal media with crops in it. There is not any duckweed concerned. In most cases, what Lemnion employs all over wastewater remedy is a hybrid device. As an example, within the first two tanks, there are media and crops. Within the 3rd tank, which will also be used as a reservoir, they use duckweed in it.
Sahil Kanekar, a senior program affiliate (City Making plans) on the Global Sources Institute (WRI)-India, a big analysis organisation, is lately operating on a pilot venture with Lemnion at IIT Bombay, the place they’re rejuvenating a stretch of stormwater runoff.
“Their answers appeared technically sound from an environmental engineering viewpoint — a lake and nullah rejuvenation or wastewater remedy with an ecological method. On the other hand, operations and upkeep post-execution for public water our bodies has been my fear. Answers like those require coordination throughout more than one departments like gardens, stormwater and forged waste, and it may possibly now and again be tricky to spot who takes possession and duty to deal with them after the venture is passed over,” says Kanekar.
The pilot at IIT Bombay is lately within the ultimate phases of implementation.
“The venture goals to regard water in a flow flowing throughout the campus and retain a portion of it to make use of to fulfill the watering wishes of the campus, in part offsetting the present water call for. The purpose is to additionally beef up get entry to of the campus citizens and guests to the native flow. We can be tracking and assessing this venture over the approaching 12 months,” he says.
Are their answers scalable? Kanekar urges warning.
“For smaller streams, that have average to no concretisation alongside the sides and the character of air pollution discharged is home handiest, those ecological rejuvenation answers will also be possible, cost-effective and convey co-benefits like biodiversity and group resilience. On the other hand, if the flow or nullah is closely concretised with conserving partitions or has a heavy commercial effluent discharge, there might be boundaries to those answers,” he says.
“Additionally, governance is a huge problem on the subject of scalability. Such answers require coordination throughout quite a lot of departments and desire a sturdy champion to effectively execute and form the protocols for operation and upkeep,” provides Kanekar.
(We’ve got gained knowledge for this text in collaboration with WRI India, an impartial charity which supplies function knowledge and sensible proposals to foster environmentally sound and socially equitable building.)
(Edited by means of Pranita Bhat; Pictures courtesy Lemnion Inexperienced Answers)