Oil palm cultivation with a cover crop to protect the soil
It is very unfortunate that the government has decided to stop the expansion of cultivation of oil palm without considering in depth, the merits and demerits. Totally banning the globally most widely used weed killer, glyphosate in 2015, was a similar folly of the previous regime, overlooking the views of the scientists and government high officials and largely on a highly erroneous scientific hypothesis that it was a causal factor in the Rajarata chronic kidney disease. The hypothesis was, however, ‘torn to bits’ by many highly qualified academics and experts on the subject and it is now clearly evident that glyphosate plays no role in the disease.
Just as much as the aforesaid faulty hypothesis led to the glyphosate ban, a ridiculous and unscientific report by the Central Environment Authority (CEA) and wild accusations by some politicians and villagers living in the oil palm growing areas appear to have led to this decision. To add to this, a senior scientist of the CEA appeared on television a few days ago and made some naïve comments supporting the ban. All his claims, the writer has dismissed below with scientific evidence.
Palm oil is the most widely consumed vegetable oil, accounting for over 42.3 percent of the global vegetable oil demand produced from only 14.8 million hectares, whereas the soya oil, which takes the second place, produces only 29.8 percent of the demand but utilises as much as 103.8 million ha. Palm oil is contained in over 50 percent of food and other products used daily. Our national vegetable demand is over 200,000 MT per annum. The local coconut oil production has over the years declined to 52,000 MT, of which the bulk is exported, but its potential for expansion of production is limited.
Moreover, the average coconut oil productivity is a meagre 0.8 MT/ha/yr, as against 4 MT of oil palm. Thus, the economic importance for the expansion of palm oil production locally cannot be overstated despite the naïve assertions of the CEA that we should go for coconut oil.
The biggest argument against oil palm is that it is not environmental friendly. There has of course been serious environmental degradation caused by opening up of large extents of tropical rain forests for oil palm cultivation in countries such as Indonesia and Malaysia. On the other hand, in Sri Lanka, oil palm is cultivated almost exclusively in ex-rubber lands and there is thus no such risk of environmental damage in our situation. The other purported environmental risks that are cited by anti-oil palm lobbyists are no more serious than those encountered with tea and rubber crops and can easily be mitigated by proper management practices as seen below.
Because of the protests by some, against the expansion of the oil palm cultivation, the government, last year, appointed a team comprising representations from the Coconut Research Institute (CRI), the organisation charged with the responsibility of oil palm research, CEA, Rubber Research Institute (RRI), Ministry of Plantation Industries (MPI) and several others, seeking observations on oil palm cultivation.
There had apparently been disagreement among the institutions on the contents of the report and therefore, it had been agreed for the individual institutions to prepare separate reports on their observations. The writer had the occasion to read all component reports and regrettably that of the CEA was not only highly unscientific but even hilarious. It is surprising that a premier organisation produced such a prejudiced report. The organisation appears to seriously lack competent scientific officers.
The main contention of the CEA is that oil palm is not as environmentally friendly as tea, rubber and coconut and because of some other considerations too, it is not recommending its cultivation expansion. It is regrettable that the CEA has lost sight of the massive soil degradation that tea has caused over the 150 years of its cultivation, replacing much of the tropical rain forests here. Calculations reveal that over the years we have lost some five foot depth of the top soil impacting very seriously on the tea productivity, despite all technology generated by the TRI for soil conversation. So, should we have banned tea cultivation?
The RRI’s objection appears to be the consumption of rubber lands by oil palm. The reason is simply the poor returns from rubber cultivation. Way back in the 1960s, Malaysia shifted its rubber-oil palm policy in terms of land use from 60 percent rubber to 40 percent oil palm to 40 of rubber to 60 of oil palm, simply on profit considerations.
By contrast, the MPI and CRI in their reports state with very valid facts that it is no less environmentally friendly than the other plantation crops. Given also the massive economic importance of oil palm, the MPI is strongly recommending the expansion of its cultivation. But the previous president, also the minister responsible for the subject of environment, ‘sat on the decision’ for months.
Does oil palm cause drying of wells and streams?
The main objection to the cultivation of oil palm by the CEA and several other environmentalists is its purported excessive consumption of water leading to drying of wells and streams in the vicinity. The CEA has based its arguments on the basis of the per tree evapo-transpiration (ET) rates of rubber and oil palm. It has been pointed out that, whereas a mature rubber tree transpires only about 63 litres of water per day, an oil palm tree transpires 249 litres.
However, scientifically, the ET should be measured on per unit area basis and not per tree. Whereas the recommended planting density of rubber is 520 trees per hectare that of oil palm is only 143, implying that the corresponding rates of ET should be 32,760 and 35,607 l/ha/day, respectively, a difference of a mere 8.6 percent. Can such a small difference in ET cause such a vast impact on drying of water sources?
The whole country (wet zone) has yet only some 16,000 ha of oil palm and the proposal is merely to increase it to 20,000 ha immediately. The increasing water consumption over the years with increasing population and global warming-related weather changes are perhaps the reason for the phenomenon. Even in non-oil palm cultivated areas of the wet zone, instances of drying of streams and wells are not uncommon.
Other absurd observations in report
Of some 15 observations in the CEA report, the large majority is baseless and some are howlers. Growing oil palm on slopes causes excessive erosion is one of them. Like rubber, oil palm plants are established along contours in platforms and the soil is usually well protected with cover crops (see photo).
Compared to tea, where the average soil loss during land preparation for replanting is over 250 tonnes/ha and soil loss continues through its life cycle, the losses with rubber and oil palm cultivation are comparatively small. It is also reported that oil palm causes soil compaction. This has been reported from cleared tropical forests but this contention is not supported by research evidence in Sri Lanka and is unlikely to be more than for rubber.
The report also contends that there is excessive use of pesticides and fertilisers in oil palm and the latter being eight to 10 times that of rubber. These are also absurdities. The use of pesticide is no greater than with other plantation crops like tea, rubber and coconut and fertiliser use is only about double that of rubber. Being a highly productive crop, high nutrient demand is to be expected like in tea.
Concern has also been raised about waste material and its disposal in the industry. Much of the carbonic waste is used for generating energy, which is used in palm oil processing and there is satisfactory effluent disposal with pollution risk being no greater than for rubber. It has also been reported that oil palm stems go waste. It may be that at present stems are not utilised here but in countries like Malaysia, where vast extents are under oil palm, the trunks have many economic uses.
One of the naive recommendations of the CEA is to expand the coconut cultivation to meet the national oil demand. The CRI studies show that the potential for expansion of coconut in the intermediate and dry zones is very limited for various reasons. One possibility, however, is to expand its cultivation in the wet zone as a shade crop in tea.
It is regrettable that the CEA did not consult the CRI as to the potential for expansion of coconut oil production before making the recommendation. The global coconut oil demand is increasing especially as virgin coconut oil and coconut has other diversified uses. Today coconut oil fetches over 30 percent more in the local consumer market than oil palm and that is why palm oil consumption has increased so rapidly.
A further argument of the CEA is that coconut oil is more health-friendly than palm oil. It is a fact that the medium chain fatty acids in coconut are health friendly but 85 percent of them are cholesterol elevating, as against 51 percent in palm oil. The balance comprising 39 percent monounsaturated fats and 10 percent polyunsaturated fats is cholesterol lowering. Thus, both oils have advantages and disadvantages in terms of health.
Most productive and profitable plantation crop
The cost of production of palm oil is the lowest of all plantation crops and the profit highest. The average net return per hectare of coconut, tea, rubber and oil palm is Rs.175,000, Rs.88,000, Rs.80,000 and Rs.612,000, respectively.
In order to make the country self-sufficient in vegetable oils, there is thus justification for conversion of 40,000 to 50,000 ha of the less productive lands planted with other plantation crops into oil palm.
Abandoning rubber
Our rubber growers are gradually abandoning rubber for alternative crops and other more profitable options of land use. The national rubber cover exceeded 200,000 ha in the 1990s but by 2015 it has decreased to 123,000 ha due to decreasing productivity, skilled labour shortages, low prices and profits.
It is a fact that over the years, with increasing population and water use as well as global warming-associated climatic changes, there is the likelihood of drying up of streams and wells. In fact, this has been an occurrence in many parts of the wet zone. Ideally, the CEA and CRI should have identified several sites growing rubber only as against oil palm plus rubber (akin to the Nakiadeniya) and conducted a comparative socio-ecological study on the water status of such sites before jumping to conclusions. At the same time, the government should have sought the views of an independent expert panel before making a decision. It is yet not too late to do so.
In conclusion, determination of what crop to grow should not be conditioned by tradition or rhetoric but by environmental suitability, sustainability and profit. Taking into consideration all these factors, oil palm overtakes the competitive plantation crops in the wet zone, viz, tea and rubber. It is ideal even for displacing unproductive rubber smallholdings. In Indonesia and Malaysia, smallholders account for 35-40 percent of the total oil palm extent, producing 33 percent of the output and their incomes have substantially increased over that from rubber. It is thus justifiable to introduce the crop to our smallholders too.
