Klein River watershed revival with biochar
A local initiative to clean up the polluted Klein River estuary in Hermanus offers residents the opportunity to make a real difference in both their community and their natural environment.
Stanfordian Luke Boshier, who has been working in the field of sustainable agriculture for more than three decades in South Africa, Uganda and Malawi, has developed a holistic solution to multiple problems. His approach involves the removal of alien vegetation and its transformation into high-quality, carbon-rich natural fertiliser to replace the chemical fertilisers used by farmers and gardeners in the 950km2 watershed, which comprises Tesselaarsdal to the east of Hermanus and the Mossel River in the west.
He’s inviting interested people to spend R250 a month to support the ReStore programme to replace chemical fertilisers on commercial farms with a natural, more sustainable alternative. In return, those members of the ReStore Club will receive a 40kg bag of ReStore biochar-chicken manure pellets every quarter for their own use as well as special offers from participating farms.
The participating farmers receive sufficient ReStore biochar fertiliser for their needs, as a means of gradually introducing them to the benefits of this new approach. Ten farms from the area have come on board in the last two years, including Stanford Valley, Stanford Hills, Misty Mountains, Stanford Harvest, White Water, Raka Wines, Kleinrivier Cheese and Stone House Cheese.
“It’s a win-win situation for the planet,” says Luke. “Water-sapping aliens, which are also a fire hazard, are removed from the natural environment; jobs are created for the wood-cutters who are self-employed; the soil is improved, and the water quality in the estuary is enhanced.
“Chemical-laden agricultural run-off is the largest pollutant in the estuary. The high levels of phosphates and nitrates in the water have led to eutrophication and hypoxia (a lack of oxygen), resulting in dead fish and an overabundance of algae and reeds.”
While most of the alien vegetation being removed in the Western Cape ends up as firewood, Luke has devised a new value-added approach. After finely chipping the alien Rooikrans and Port Jackson willow, it is put through a purpose-built 600°C kiln where it is transformed into high-quality carbon or biochar. The beauty of this process is that the end product is also the fuel for the kiln. This is then combined with chicken manure and made into pellets, which are easily distributed on agricultural land or in gardens. After two waterings, the pellets break down, leaving a stable form of highly beneficial carbon in the soil.
“Carbon in this pure form has a phenomenal capacity to hold water as well as nutrients that plants need to grow, such as nitrogen. Western Cape soils are traditionally very poor, with about a 1% carbon content on average. And while this may be suitable for fynbos, sustainable agricultural soils for food production require between 3 – 5% carbon. Thus, when chemical fertilisers are put on these sandy soils and watered, most of the chemicals leach away and run off into the watershed as the soil has a very little holding capacity for nutrients or micro-organisms.”
Luke says the biochar, which is stable or fixed carbon, will remain indefinitely in soils, providing benefits for many generations. “If we could get the carbon content of our agricultural soils as high as 5%, we could reduce our chemical input by 60 – 70%, resulting in significant savings, and ultimately do away with synthetic fertilisers altogether and become totally organic.”
Dr Johann Strauss, a senior researcher in the Directorate of plant sciences of the Western Cape Department of Agriculture, is very excited about the potential of biochar. “We are planning to conduct a multi-enterprise, regenerative farming, 12-year trial from April this year, which will include growing canola, wheat and barley using the ReStore biochar pellets. Regenerative farming is about improving the soil quality in such a way that there is no need to add herbicides, insecticides or synthetic fertilisers, as we realise this old approach is far from ideal.”
Luke adds: “Too many economies are now reliant on the synthetic fertiliser industry, which is bringing our environment to its knees. Some of the big rivers in the Western Cape, such as the Berg River which enters the sea at Saldanha, contain so many chemicals that the estuaries are dead zones. Other rivers of major concern in our area are the Breede at Witsand and Hartenbos at Mossel Bay. In the US, the Gulf of Mexico has a dead zone as large as the state of Connecticut, largely as a result of agricultural leaching, factory detergents and unprocessed sewage.
Luke says the pilot ReStore project in the Klein River watershed could be used as a blueprint for cleaning up other watersheds in South Africa. “We have compromised our planet for short-term profit. It’s time we, as the human race, took a regenerative approach to agriculture. Scientists have predicted that if we carry on with commercial farming as we are, there are only 50 – 60 harvests left. We’re not producing food, but a chemical concoction. We need to boost the quality of our soils, so they can hold water and nutrients better, reduce our reliance on synthetic fertilisers and reduce seepage.” He also adds that climate change and the resulting drought have left South African farmers in a very precarious position.
This is the third year that Burt du Toit, farm manager at Stanford Valley Guest Farm, has been using biochar on the farm’s three hectares of organic vineyards, half a hectare of organic vegetables and five hectares of lawn. Says Burt: “Three years ago, when we planted our first vines, Luke introduced us to the biochar powder and the subsequent year we began using the pellets. It is an excellent product and I have been very surprised about the resultant short- and long-term growth. Our water consumption has also fallen drastically: instead of watering the vines every three days, we only have to water every four days. And the clay in which more than half a hectare of vines stand has already become usable black soil.”
* For more information, contact Luke Boshier of ReStore on lukeboshier@gmail.com. You can also visit the ReStore Facebook page and view a short VIDEO, featuring Athol McConey from Stanford Harvest.