Opinion

Harvesting Aquatic weed for biofertiliser – another dead rope for the farmer?

Published

5 years ago

2021/05/22

By Chandre Dharmawardana, Canada

Mr. I. C. P. Mendis, writing to The Island (“The organic deal – killing two birds with one stone”, 15-05-21) proposes to harvest aquatic weeds like Water Hyacinth (“Japan Jabara”) to make organic biofertiliser and clearing the water ways, too. This suggestion is preceded by a conspiratorial theory mentioning Dr. Senaka Bibile, an old colleague of mine, who pushed for generic pharmaceuticals. Then Mr. Mendis meanders into claiming that those who support the use of agrochemicals are treacherous agents of multinational companies who are only interested in profits.

Mr. Mendis says, “The defeated forces have now received some oxygen, and we see even the high and mighty, who were sent reeling home at the polls, attempting to make their presence felt. There is everything which points to financing by the fertiliser lobby, against the organic fertiliser issue”.

Mr. Mendis forgets that those who were defeated at the polls also championed organic fertiliser, under the slogan of a “Toxin-free Nation” and even banned glyphosate. This government has exempted many such pesticides and key agrochemicals from the “ban” which seems to be mostly in name.

After hatching the conspiracy claim, Mr. Mendis suggests making organic fertiliser, and possibly bio-energy out of the aquatic weeds dragged off the water and processed. Farmers, or commercial outfits are called upon to do this. He has himself NOT tested it, as is typical of most suggestions for “going organic”.

In my view, adopting a full organic programme worldwide is environmentally bad for the world (and impossible for Lanka) because it needs twice as much land, and twice as much water to put into practice. Then there is the danger of plants accumulating metal toxins (phyto-accumulation) and those getting into manure when plant matter is recycled by composting. Adrian Meuller, a leading world authority advocating organic farming wrote a lead article on organic farming in the journal NATURE and showed that if the world were to “go.organic”, the world population must be halved, and they should become vegetarians to free up cattle ranching land for growing food. A link to Mueller’s work may be found in my comment on Mueller’s research given in the link:.

https://dh-web.org/place.names/posts/CD-Mueller-OrganicL.pdf

The right solution is a hybrid approach. BUT SRI LANKA’S PROBLEM IS NOT ORGANIC VERSUS MINERAL FERTILISER. IRRESPECTIVE OF WHAT FERTILISERS WERE USED, THE FARMER CANNOT GET HIS PRODUCT TO THE MARKET. An indebted farmer cannot implement cutting edge ecologically sound farming practice. All the price guarantees, and purchase schemes of successive governments have been a farce. So what is the use of talking about fertilisers, pesticides, good agricultural practices, etc., if in the end the farmer cannot market his prodcut, and he/she is forced to even commit suicide? In contrast, the plantation sector has a good marketing system since colonial times. There is no excuse as to why good agricultural practices, soil remediation, etc., have not been adopted by, say, tea estates.

Unfortunately, instead of tacking the real issues of the small farmer, all kinds of irrelevant solutions are proposed. Let us look closely at Mr. Mendis’s proposal because such suggestions were tossed out even in the 1970s when I worked as a Professor of Chemistry at what is today the SJP university. The basic numbers to evaluate the feasibility of such projects have been avialble for a long time.

Eichhornia crassipes (Water Hiacynth) and various types of aquatic Ipomea, Hydrilla, Ceratophyllum are found on water bodies that receive the nutrient-rich run off from agricultural land and grabage dumps. Typically 20% or more of the water surface may get covered, and Ceratopphyllum and Hyrdilla may develop submerged thick mats that asphyxiate the aquatic system. However, harvesting the voluminous material from the water poses grave problems:

(a) collecting them into drying beds or composting areas equires heavy dredging equipment that burn expensive fossil fuel.

(b) The harvest, when dried, is negligible. Thus, 1000 square meters of aquatic area usually provides about 800-900 kg of dry material, although the harvested wet weight is 9-10 tonnes. The ten tonnes of wet smelly material cannot be easily dried in the sun and need special kilns,. It cannot be directly composed without mixing with suitable dry material. In effect, it is very inconvenient and expensive to work with.

(c) The composted material, even under the best conditions contains only 2-2.5 % nitrogen. That is, ten tonnes of initial material produces merely 15-20 kg of nitrogen fertiliser after much investment in energy, and machinery!

What Mr. Mendis in his goodness of heart has done is to give a “dead rope” to the farmer. At the end of the day the farmer is left bankrupt while the elites who clamour for organic food on their plate will look after themselves somehow.

The impact on the aquatic system of the lake is also not unfavourable. The sudden removal of the top layers of the aquatic weeds lets sunlight into the submerged weeds which now grow profusely. It is well known that aquatic weeds cannot be controlled in this naive manner of simple harvesting of the surface growth. It is mechanically quite demanding and expensive to remove all the submerged growth as well.

In fact, when a lake is clogged, many complex methods of reclaiming are needed. This includes the introduction of fish species (“grass carps”) that eat up the submerged growth, and then harvesting the surface growth gradually. In addition, control of soil erosion and run off from the neighbouring urban and agricultural lands need to be undertaken.

The best solution to prevent aquatic weed growth it to put floating solar panels on the water. Then no aquatic growth occurs submerged or on the water surface. Water is conserved by the reduction of evaporation day and night, and electric power is produced during the day time.

Mr. Mendis has been carried away by a seemingly simple but mostly impractical idea. Similar proposals to convert plastic into petrol, purify water with “kumbuk” roots, provide potassium to soils with left over banana skins, tackling Covid with coriander, ginger and herbal smokes (“dhum hattiya”), or asking the farmer to make his own fertiliser with a few buckets of cow-dung and a few bales of straw in his own “kumbura” are very fashionable these days. An individual introduced as a Professor of Agricultural, speaking on a TV programme claimed that imported oranges, i.e., “rata dodan” do not contain Vitamin C. Only the local “paeni dodan” was claimed to have Vitamin C.

I have written many articles pointing out that the claim that “Sri Lanka’s rivers and soils are contaminated with poisons” is an utter falsehood. Chemical analysis of the river waters and soil have shown no significant amounts of heavy metals or pesticdes.

If “people eat posisoned food”, as claimed by the ochestrations for organic food, the life expectance should drop drastically due to chronic toxicity. Countries like Singapore and New Zealand, etc., use some 100 times more argochemicals per hectare compared to Sri Lanka, and the life expectancy in those countries have INCREASED since the days prior to modern agriculture. The incidence of cancer, kidney disease, etc., has NOT increased in Si Lanka with time. Instead, the disease has decreased and the life expectancy has increased. The kidney disease endemic in the Rajarata is a result of hurriedly settling farmers in the accelerated Mahaweli C programme in areas where the water in their dug wells is found to be contaminated with fluoride and magnesium ions of geological origin.

In a very recent U-tube emission Dr. Padeniya of the GMOA claims that since 1960, Sri Lankans have been EATING POISON IN THEIR FOOD. Mr. Mendis also seems to think so, and want people to eat only organic food. But the attached graph shows that the life expectancy in Sri Lanka has steadily increased, except during the Eelam wars.

So Mr. Mendis, and Dr. Padeniya, what kind of poison in the food increases the life expectancy of Lankans? What kind of posion decreases infant mortality?

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Opinion

A harsh reflection of Sri Lanka’s early-warning gap

Published

21 hours ago

2025/12/17

Sahan Weerasooriya

Floods caused by Cyclone Ditwah

Cyclone Ditwah:

Cyclone Ditwah, which swept across Sri Lanka at the end of November, caused massive damage to the country, the extent of which need not be mentioned here, as all are aware of it by now. Heated arguments went on among many parties with regard to how this destruction could have been mitigated and who should take responsibility. Although there may have been shortcomings in several aspects of how we responded to Ditwah, this article highlights a critical area that urgently requires attention if we are to protect ourselves from similar hazards in the future.

As is common in many situations, it has once again showcased a concerning weakness in the country’s disaster-management cycle, the gap between issuing early warnings and the expected public response. The Meteorological Department, the Irrigation Department, the National Building Research Organization, and other authorities issued continuous warnings to evacuate well in advance of imminent threats of flooding, landslides, and water hazards. However, the level of preparedness and community reaction fell short, leading to far greater personal property damage, including loss of a few hundred lives.

Sri Lanka is not unfamiliar with natural disasters. One of the most devastating disasters in our history could be considered the 2004 Tsunami event, which resulted in over 35,000 deaths and over $1 billion in property damage in the coastal belt. After the event, the concepts of disaster management were introduced to the country, which we have been adhering to since then. Again in 2016, the country faced massive river flooding, especially in western and southern regions, and until recently experienced repeated floods and landslides due to rains caused by atmospheric disturbances, though less in scale. Each of these events paved the way for relevant authorities to discuss and take appropriate measures on institutional readiness, infrastructure resilience, and public awareness. Yet, Cyclone Ditwah has demonstrated that despite improvements in forecasting and communication, well supported by technological advancements, the translation of warnings into action remains critically weak.

The success of early-warning systems depends on how quickly and effectively the public and relevant institutions respond. In the case of Ditwah, the Department of Meteorology issued warnings several days beforehand, supported by regional cyclone forecasting of neighbouring countries. Other organisations previously mentioned circulated advisories with regard to expected flood risk and possible landslide threats on television, radio, and social media, with continuous updates. All the flood warnings were more than accurate, as low-lying areas were affected by floods with anticipated heights and times. Landslide risks, too, were well-informed for many areas on a larger spatial scale, presumably due to the practical difficulties of identifying such areas on a minor scale, given that micro-topography in hill country is susceptible to localised failures. Hence, the technical side of the early-warning system worked as it should have. However, it is pathetic that the response from the public did not align with the risk communicated in most areas.

In many affected areas, people may have underestimated the severity of the hazard based on their past experiences. In a country where weather hazards are common, some may have treated the warnings as routine messages they hear day by day. As all the warnings do not end up in severe outcomes, some may have disregarded them as futile. In the meantime, there can be yet another segment of the population that did not have adequate knowledge and guidance on what specific actions to take after receiving a warning. This could especially happen if the responsible authorities lack necessary preparedness plans. Whatever the case may be, lapses in response to early warnings magnified the cyclone’s impact.

Enforcing preventive actions by authorities has certain limitations. In some areas, even the police struggled to move people from vulnerable areas owing to community resistance. This could be partly due to a lack of temporary accommodation prepared in advance. In some cases, communities were reluctant to relocate due to concerns over safety, privacy, and the status quo. However, it should be noted that people living in low-lying areas of the Kelani River and Attanagalu Oya had ample time to evacuate with their valuable belongings.

Hazard warnings are technical outputs of various models. For them to be effective, the public must understand them, trust them, and take appropriate action as instructed. This requires continuous community engagement, education, and preparedness training. Sri Lanka must therefore take more actions on community-level disaster preparedness programs. A culture of preparedness is the need of the day, and schools, religious institutions, and community-based organisations can play an important role in making it a reality. Risk communication must be further simplified so that people can easily understand what they should do at different alert levels.

Cyclone Ditwah has left, giving us a strong message. Even an accurate weather forecast and associated hazard warnings cannot save lives or property unless the public responds appropriately. As it is beyond doubt that climate change intensifies the frequency and severity of extreme weather events, people in Sri Lanka have to consider preparedness as a routine part of life and respond to warnings promptly to mitigate damage from future disasters.

(The writer is a chartered Civil Engineer)

by Eng. Thushara Dissanayake

Opinion

Feeling sad and blue?

Published

2 days ago

2025/12/16

Sahan Weerasooriya

Rowan Atkinson

Here is what you can do!

Comedy and the ability to have a good laugh are what keep us sane. The good news to announce is that there are many British and American comedy shows posted up and available on the internet.

They will bring a few hours of welcome relief from our present doldrums.

Firstly, and in a class of its own, are the many Benny Hill shows. Benny is a British comedian who comes from a circus family, and was brought up in an atmosphere of circus clowning. Each show is carefully polished and rehearsed to get the comedy across and understood successfully. These clips have the most beautiful stage props and settings with suitable, amusing costumes. This is really good comedy for the mature, older viewer.

Benny Hill has produced shows that are “Master-Class” in quality adult entertainment. All his shows are good.

Then comes the “Not the Nine o’clock news” with Rowan Atkinson and his comedy team producing good entertainment suitable for all.

And then comes the “Two Ronnies” – Ronnie Barker and Ronnie Corbett, with their dry sense of humour and wit. Search and you will find other uplifting shows such as Dave Allen, with his monologues and humour.

All these shows have been broadcast in Britain over the last 50 years and are well worth viewing on the Internet.

Similarly, in The USA of America. There are some really great entertainment shows. And never forget Fats Waller in the film “Stormy Weather,” where he was the pianist in the unforgettable, epic, comedy song “Ain’t Misbehavin”. And then there is “Bewitched” with young and glamorous Samantha Stevens and her mother, Endora who can perform magic. It is amazing entertainment! This show, although from the 1970s was a milestone in US light entertainment, along with many more.

And do not overlook Charlie Chaplin and Laurel and Hardy, and all the Disney films. Donald Duck gives us a great wealth of simple comedy.

The US offers you a mountain of comedy and good humour on Youtube. All these shows await you, just by accessing the Internet! The internet channel, ‘You tube’ itself, comes from America! The Americans reach out to you with good, happy things right into your own living room!

Those few people with the ability to understand English have the key to a great- great storehouse of uplifting humour and entertainment. They are rich indeed!

Priyantha Hettige

Opinion

There is much to learn

Published

2 days ago

2025/12/16

Sahan Weerasooriya

After the recent disaster, a great deal of information has been circulating on WhatsApp and YouTube regarding our reservoirs, highways, etc.

In many of these discussions, people have analysed what went wrong and how the damage could have been prevented. My question is this: why do all these knowledgeable voices emerge only after disaster strikes? One simple reason may be that our self-proclaimed, all-knowing governing messiahs refuse to listen to anyone outside their circles. It is never too late to learn, but has any government decision-maker read or listened to these suggestions?

When the whole world is offering help to overcome this tragedy, has the government even considered seeking modern forecasting equipment and the essential resources currently not available to our armed forces, police, and disaster-management centres?

B Perera