Although cycads are not endemic to our area, the general state of cycad species in our country is of great concern to all who are in favour of a balance in nature.
Cycads are the most threatened group of plants on earth, with 62% classified as threatened in the 2010 IUCN global assessment. South Africa is a cycad diversity hotspot, with 37 species in die genus Encephalartos, yet 78% are threatened with extinction. The greatest threat to our cycads is illegal harvesting from the wild. Three species are already extinct in the wild, four are close to extinction, and another seven have fewer than 100 individuals remaining. The rate of loss has placed the existence of wild cycads on a knife’s edge.
A collaborative study between the SA National Biodiversity Institute and UCT is developing a solution to regulate the illicit trade in cycads by using stable isotopes to distinguish between wild and cultivated cycads. Having been used in numerous forensic studies, stable isotopes are now being applied to cycads.
As from May 2012, it is prohibited to harvest, trade, sell, buy, donate, import, export, convey or receive any wild indigenous cycad (even plants that have possession permits). If you suspect foul play, report this to the Department of Environmental Affair’s Environmental Crimes Hotline: 0800 205 005 (KZNCA email, 15 June 2015).
Healthy soil is the foundation of agricultural ecosystems. It builds healthy agricultural economies that, in turn, support national economies. “Soil is teeming with micro-organisms, fungi and bacteria. Just one teaspoon contains more than 100 000, and farmers, growers and gardeners are becoming aware of the huge role they play” (Bunny Guiness).
South Africa is a water-scarce country, and there is limited soil for agricultural production. Of the 100 million ha of farm land in South Africa only 12,75 million ha is arable agricultural land, some of which is prime land, i.e. more arable than the bulk. In fact, a full 47% of agricultural land is unsuited to cultivation of any kind, suitable only for grazing, game, recreation, etc. Using techniques such as no-till planting, deep mulching with natural compost, companion planting and conservative drip irrigation, helps with carbon sequestration and lowers the loss of carbon and moisture from the soil. It prevents large-scale erosion through wind and water and improves soil health, leading to improved yield and sustainable production over time. Maximum cover on top of the soil – plants, either living or dead, serve as armour for the soil, just as our epidermis forms an armour against the sun and rain. It keeps the soil cooler in summer and warmer in winter, provides food for the soil organisms that help sequestrate carbon, and builds soil structure. For every one percent of added carbon to the soil, the water-holding capacity of that soil doubles (Dr Johan Strauss & Richard Findlay, Farmers Weekly, 14 October 2014).
According to soil health expert, dr Jill Clapperton, healthy soil will comprise a large number of functioning soil services, including: Limited soil erosion due to high soil organic matter content; increased nutrient cycling; good nutrient availability and nutrient recycling; good water-holding capacity and water filtering; and good biodegrading of potentially toxic compounds from the likes of chemical fertilisers and agricultural chemicals in the soil: “Today’s intensive use of nitrogen fertilisers, besides supplying the most important plant nutrient for achieving high yields, is generally believed to build soil organic matter by increasing the input of residue carbon as well as supplying nitrogen, itself a key constituent” (‘The Browning of the Green Revolution’ by RL Mulvaney, SA Khan & TR Ellsworth).
Did you know?
Humus is a complex and rather resistant mixture of brown or dark brown amorphous and colloidal organic substance which results from microbial decomposition and synthesis, and it has chemical and physical properties of great significance to soils and plants (Gauteng Smallholder, September 2015).