We are facing the Sixth Extinction?

We are facing the Sixth Extinction?

Image a world devoid of plants, insects, and mammals – a world lifeless and empty.  Daily we read about insect populations plummeting and the dire consequences thereof.  A world without insects is inconceivable. They have essential roles in terrestrial and freshwater ecosystems as herbivores, carnivores, and decomposers; they are the pollinators par excellence and represent an extraordinarily promising source of proteins for the continuously-and alarmingly- growing human populations. Singling out only one insect,  where would we be without bees? As far as important species go, they are top of the list. They are critical pollinators: they pollinate 70 of the around 100 crop species that feed 90% of the world.  We may lose all the plants that bees pollinate, all of the animals that eat those plants and so on up the food chain. Which means a world without bees could struggle to sustain the global human population of 7 billion.  We are losing bees at an alarming rate. Possible reasons include the loss of flower meadows, the crab-like varroa mite that feasts on their blood, climate change, and use of pesticides. Insects are not charismatic animals  such as elephants, rhinos or whales, thus they receive much less consideration and empathy from humans.  However, their relationship with humans is of such importance that few lay people realize it. The general public tends to dislike insects for multiple reasons: some species are vectors of serious diseases (mosquitoes, fleas), others destroy their crops (locusts, beetles, true bugs) or attack livestock  (flies, lice), although some are considered objects of beauty (butterflies). Insects are key components for the functioning of the world’s ecosystems. Their accelerated decline in numbers and extinction due to man made activities could cause unpredictable negative consequences for the biosphere. It is a duty of all entomologists to attack this enormous problem and educate the public on the importance of saving our fantastic insects. Although five massive extinctions of life on Earth have occurred in the distant geological past, it is considered that present-day biodiversity  is the largest in all the history of life. At the same time the extinction rate due to the influence of human beings on nature;  habitat destruction, over-harvesting, pathogens, pesticides, pollution, urbanization, transport of invasive species, and greenhouse gases emissions  is probably thousands of times larger than the background rate. As poet Munia Khan put it: “Bugs never bug my head. They are amazing.  It is the activities of humans which actually bug me all the time.” Ref:  Bidau CJ (2018) Doomsday for Insects? The Alarming Decline of Insect Populations around the World. Entomol Ornithol Herpetol 7: e130 Share this:Click to email this to a friend (Opens in new window)Click to print (Opens in new window)Click to share...

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Brenton Hills are Alive… Part 2

Brenton Hills are Alive… Part 2

What a joy to walk in the Brenton hills and find them alive with (no, not the sound of music) an amazing variety of fynbos plants. From a distance it may look as though only the yellow Bietou bushes are growing, but walk along little tracks and you will find pink and white and purple and mauve and orangey-yellow as well as lemon yellow, bright yellow – in fact flowers of every colour of the rainbow. The flowering plants are surrounded by soft, bright green grasses and many different species of restios which create a soft gentle landscape – punctuated by the stark, burnt remains of trees – a harsh reminder of the devastating fires of 2017. The Bietou (Chrysanthemoides moniliferum) bushes are providing shelter, as are the bushes of Strand salie or Dune sage (Salvia africana-lutea), for the more fragile plants which are now thriving. There are pink and purple pelargoniums, mauve Veld cineraria (Senecio elegans), Bloublommetjies (Felicia echinata), and apricot-coloured Indigofera zeyhe. Yellow flowers of every description can be found, from daisies of the Euryops species, the little yellow bell-shaped flowers of the Hermannia species, yellow pea-shaped flowers of the Cape Gorse (Aspalathus spinosa) to wonderful large bushes of yellow pincushions (Leucospermum cuneiforme). This pincushion is extremely fire resistant as its rootstock has no problem regenerating, and ants ensure that it has a second survival string to its bow. The pincushion seeds have a fleshy coating containing nutrients that ants like. So the ants take the seeds down to their underground nests and eat the coating without damaging the actual seed. The seeds are therefore safely stored underground while the fires rage overhead, and after the fires die down the seeds can germinate to regenerate the pincushion population. One of the loveliest plants we found was the fragrant and beautiful white Freesia alba, now known as the Freesia leichtlinii subsp. alba. This freesia with a faint purple flush on the outside and a yellow splodge on the lowest petal has the sweetest fragrance of all the freesias. It is no wonder that it became a sensation when it appeared in the English nursery trade in the second half of the 19th century and soon spread to Europe and North America. Breeding started immediately and most of the hybrids available from nurseries today are derived from this little freesia, which grows in the stony, sandy soil of the southern Cape, as well as the more widespread Freesia corymbosa. Leonie Twentyman Jones Photos by Margaret Richards & Leonie Twentyman Jones Share this:Click to email this to a friend (Opens in new window)Click to print (Opens in new window)Click to share on Facebook (Opens in new window)Click to share on...

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WETLANDS DISAPPEARING 3 TIMES FASTER THAN FORESTS: STUDY

Journalist Nina LARSON, AFP | Friday, 28 September 2018, 07:36 Wetlands are being lost three times faster than forests, and the impact on accelerating climate change could be devastating, the Ramsar Convention has warned. LIFESTYLE NEWS – Wetlands, among the world’s most valuable and biodiverse ecosystems, are disappearing at alarming speed amid urbanisation and agriculture shifts, conservationists said Thursday 27 September, calling for urgent action to halt the erosion. “We are in a crisis,” Martha Rojas Urrego, head of the Ramsar Convention on Wetlands, told reporters in Geneva, warning of the potential devastating impact of wetland loss, including on climate change. The convention, adopted in the Iranian city of Ramsar nearly a half-century ago, on Thursday issued its first-ever global report on the state of the world’s wetlands. The 88-page report found that around 35 percent of wetlands – which include lakes, rivers, marshes and peatlands, as well as coastal and marine areas like lagoons, mangroves and coral reefs – were lost between 1970 and 2015. Today, wetlands cover more than 12 million square kilometres (4.6 million square miles), the report said, warning that the annual rates of loss had accelerated since 2000. “We are losing wetlands three times faster than forests,” Rojas Urrego said, describing the Global Wetland Outlook report as a “red flag”. While the world has been increasingly focused on global warming and its impact on oceans and forests, the Ramsar Convention said wetlands remain “dangerously undervalued”. Thursday’s report, released in advance of a meeting of the parties to the convention in Dubai next month, stressed the importance of wetlands to all life on Earth. Don’t drain the swamp Directly or indirectly, they provide almost all of the world’s consumption of freshwater and more than 40 percent of all species live and breed in wetlands. Animals and plants who call wetlands home are particularly vulnerable, with a quarter at risk of extinction, the report said. Wetlands also provide a livelihood for more than one billion people, while mitigating floods and protecting coastlines. They are also a vital source of food, raw materials and genetic resources for medicines. The East Asian-Australasian Flyway. The Ramsar Convention stressed that wetlands are essential to reining in climate change, pointing out that peatlands store twice as much carbon as the world’s forests, even though they cover just three percent of all land surface. Salt marshes, seagrass beds and mangroves also store large quantities of carbon. So when wetlands disappear, carbon that has been safely locked in the soil is released into the atmosphere. Climate scientists have long warned of the threat of so-called positive feedbacks – a vicious circle of global warming – but their fears have focused primarily on the potent greenhouse...

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Does South Africa have a microplastic problem? Our research says yes.

Does South Africa have a microplastic problem? Our research says yes.

Author Henk Bouwman Research Professor Ecotoxicology , North-West University Disclosure statement Henk Bouwman receives funding from the Water Research Commission. Partners The Conversation is funded by the National Research Foundation, eight universities, including the Cape Peninsula University of Technology, Rhodes University, Stellenbosch University and the Universities of Cape Town, Johannesburg, Kwa-Zulu Natal, Pretoria, and South Africa. It is hosted by the Universities of the Witwatersrand and Western Cape, the African Population and Health Research Centre and the Nigerian Academy of Science. The Bill & Melinda Gates Foundation is a Strategic Partner. more Republish this articleRepublish our articles for free, online or in print, under Creative Commons licence. Surface water from the Vaal River is highly polluted with fragments of microplastics. Flickr/Paul Saad  Email  Twitter15  Facebook100  LinkedIn  Print The dangers of plastics, and more specifically microplastics, is increasingly grabbing the world’s attention. A growing body of research shows that plastics and microplastics in the marine environment are having a devastating effect on life in the sea. The impact has been tracked particularly closely in laboratory setups where conditions can be managed and effects monitored. At any size, plastics pose a threat to living organisms. In the sea they can block whales’ digestive tracts, entangle sea turtles and affect the photosynthesis of algae. They’re also a problem in rivers and fresh water lakes. Microplastics are generally understood to be pieces, particles, or fibres less than 5 mm long. They have three major sources. The first is when large bits of plastic break down into tiny pieces not clear to the eye. The second is when fibres are shed from fabrics during use and washing. And the third is microbeads. These are also tiny and are manufactured to be used in products ranging from tooth paste to facial scrubs, and sandblasting. The use of plastics has become ubiquitous over the past 50 years. Most consist of stable polymers that have lots of useful properties. They are light in weight, strong, pliable and can be made into many different forms. And by combining plastics with a range of additives, products can be dramatically changed. This extends from colour to hardness and pliability. This means that they can be used in a host of innovative ways including affordable food protection and packaging, piping, ropes and netting, construction materials and windows. But, in most cases, products made out of plastic have a long durability and often outlasting their utility. They eventually become waste and enter the environment. A great deal of research has been done on the effect of microplastics on marine life as well as fresh water in developed countries. But the knowledge gaps in developing countries such as South Africa are huge. At the request of South Africa’s Water Research Commission – South Africa’s...

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ALIEN INVASIVE PINES FUELLED KNYSNA FIRES

ALIEN INVASIVE PINES FUELLED KNYSNA FIRES

KnysnaPlett Herald Thursday, 13 September 2018, 13:02 Orderly plantations of pine trees in the background, and invasion by escaped pines on the Garcia Pass in the Southern Cape. These invasions can substantially increase fuel loads, leading to more intense and damaging wildfires. Photo: Brian van Wilgen KNYSNA NEWS – The replacement of natural fynbos vegetation with pine plantations in the Southern Cape, and the subsequent invasion of surrounding land by pine trees significantly increased the severity of the 2017 Knysna wildfires. This is one of the findings of a study published in the journal Fire Ecology by a research team from the DST-NRF Centre of Excellence for Invasion Biology (CIB) at Stellenbosch University, Nelson Mandela University, Sanparks, and the CSIR. The aim of the study was to assess the climatic, weather and fuel factors that contributed to one of the region’s worst fires ever recorded. Satellite imagery used Over four days in June 2017, the Knysna fires burnt 15 000 hectares, claiming the lives of seven people and destroying more than 5 000 hectares of commercial pine plantations and over 800 buildings. The researchers used satellite imagery to compare the landscape before and after the fire, including the type of vegetation covering the different areas. This information enabled them to estimate the amount of biomass consumed by the 2017 fire. One of the main findings is that the severity of the fire was significantly higher in plantations of invasive alien trees and in fynbos invaded by alien trees than in “uninvaded” fynbos. And while the weather conditions were extreme, they were not unprecedented, as similar conditions occurred in the past at a rate of about one day every three years. The severity of the 18 to 24 months of drought that preceded the fires, on the other hand, was higher than ever recorded in the historical weather record, and this contributed significantly to the impact of the fire. Increased fuel loads Professor Brian van Wilgen, a fire ecologist with the CIB and one of the co-authors, says large tracts of natural vegetation in the Southern Cape have been systematically replaced with plantations of Pinus and Eucalyptus species, increasing above-ground biomass from about four to 20 tonnes per hectare: “Given that more than two-thirds of the area that burned was in one of these altered conditions, our findings demonstrate clearly that fuel loads have substantially increased compared to earlier situations when the landscape would have been dominated by regularly burned ‘uninvaded’ natural vegetation.” A burned-out plantation near Harkerville, shortly after the 2017 wildfire. Photo: Johan Baard It is estimated that pine trees have invaded more than 90% of the Garden Route National Park’s fynbos vegetation at various densities. Additional invasions...

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SPRING SHOWS POSITIVE SIGNS OF RECOVERY IN KNYSNA

SPRING SHOWS POSITIVE SIGNS OF RECOVERY IN KNYSNA

Thursday, 13 September 2018, 07:25 Spectacular regrowth of Fynbos was found on the slopes above Brenton-on- Lake and elsewhere in the Knysna burn scar. KNYSNA NEWS – “A recent survey throughout the Knysna burn scar showed that there is very positive indigenous plant regrowth to be found throughout the landscape. With favourable rains in the Knysna area, coupled with an early spring and longer daylight hours, Fynbos is making a strong comeback. Known to be dependent on cycles of wildfire for regeneration, the Fynbos in the area no doubt benefitted from the 2017 Knysna fire disaster,” says Cobus Meiring of the Southern Cape Landowners Initiative (SCLI). Conservationists across the country shared concern on the damage caused by the intense wildfires that ravaged the Knysna countryside in June 2017. Chased by extremely strong winds and fuelled by dense stands of invasive alien biomass littering the countryside, the wildfire that swept through areas such as Buffels Bay, Brenton and Rheenendal was intensely hot, reaching several thousand degrees centigrade. In most places, all that remained in terms of vegetation, was barren sand. There were serious concerns expressed that, because of the intense heat which was generated, the Fynbos seed bank, hidden in the topsoil, might have been completely destroyed, along with vital nutrients and insect life. According to Meiring, a further concern was that denuded landscapes would be completely covered by a wave of invasive alien plants, which are known to outcompete indigenous plants, such as Low-land Fynbos. A recent survey throughout the burn scar, however, showed that there is very positive indigenous regrowth to found throughout the landscape. A recent survey throughout the burn scar, however, showed that there is very positive indigenous regrowth to found throughout the landscape. With favourable rains in the Knysna area, coupled with an early spring and longer daylight hours, Fynbos is making a strong comeback. Suppressing invasive alien growth yields positive results around Knysna “The herbicide assistance programme rolled out on selected properties by the Southern Cape Fire Protection Association (SCFPA), and sponsored through Nedbank and WWF SA, provided assistance to the respective landowners to very effectively stemmed the growth of invasive alien plants, allowing indigenous plants to flourish,” says Meiring. In addition, the fire gave landowners a clean slate in terms of vegetation types on their land, and an opportunity to gain the upper-hand in dealing with invasive alien plants such as wattle, blackwood and Rooikrans. With favourable rains in the Knysna area, coupled with an early spring and longer daylight hours, Fynbos is making a strong comeback. The Southern Cape Landowners Initiative (SCLI) is a public platform and think tank for landowners and land managers with an interest in invasive alien plant management,...

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