#fragileplanet

Tons of dead fish have been removed from a Rio de Janeiro lagoon where Olympic events are to be held in 2016, sparking debate among officials and scientists over what caused the mass die-off, as well as fears that the water may be unsafe for athletes.

Eco-boats commissioned to clean the lagoon have already collected more than 50 tons of dead twait shad, a small silvery fish, NPR reported from Brazil on Tuesday, and were still collecting more.

The die-off took place in Rio’s Guanabara Bay, where Olympic sailing and rowing events are slated to be held in August of next year. Some athletes who plan to compete in the water events have voiced health and safety concerns over the waters.

The die-offs are becoming a common occurrence in Rio, where rivers, lakes and even the ocean are blighted by raw sewage and garbage. Officials have argued over the cause, with Rio’s environmental secretariat insisting last week that the incident is the result of the sudden change in water temperature.

“The intense rains that happened last week and a rise in the sea levels led to a spike in the [sea] water entering the lake, causing a thermal shock,” the secretariat said in a statement, adding that the water temperature had fallen by 7.2 degrees Fahrenheit in a short period of time.

Many scientists disagreed with that explanation, pointing to pollution instead.

The lake “has large concentrations of sulfur because of the organic material dumped into it, and depending on the winds, that material rises to the surface and kills fish,” said Estefan Monteiro de Fonseca, an oceanographer at the Fluminense Federal University.

Cristina Castelo Branco, an associate professor of aquatic ecology at the Federal University of Rio de Janeiro, also attributed the fish deaths to pollution, but in a different way.

Castelo Branco said that pollution from fertilizer, wastewater and storm-water runoff is affected by sunlight, warm temperature and slow-flowing water to produce algal blooms. The algae sucks out oxygen from the water, leading to fish deaths.

“This is a stressed lagoon. We have some problems with oxygen,” Castelo Branco told NPR.

Algal blooms have also caused toxicity levels to spike, which could harm people exposed to the lagoon’s waters, Castelo Branco added.

When toxicity is high, “you cannot swim in the lagoon in that situation,” she said.

Rio’s water quality has become one of the most contentious issues heading into the 2016 Olympics.

Authorities have long said that the games would be the catalyst for a major cleanup of the city’s waterways, but as the showcase sporting event approaches with few improvements, authorities are now admitting that many of the Olympic promises won’t be met.

Rio Governor Luiz Fernando Pezao acknowledged last week that “there’s not going to be time” to finish the cleanup ahead of the games, suggesting it might wrap up by the end of 2018 instead.

Fonesca, the oceanographer, warned that if another fish die-off occurs during the games, “Rio’s image could suffer irreparable damage.”

Tons of dead fish have been removed from a Rio de Janeiro lagoon where Olympic events are to be held in 2016, sparking debate among officials and scientists over what caused the mass die-off, as well as fears that the water may be unsafe for athletes.

Eco-boats commissioned to clean the lagoon have already collected more than 50 tons of dead twait shad, a small silvery fish, NPR reported from Brazil on Tuesday, and were still collecting more.

The die-off took place in Rio’s Guanabara Bay, where Olympic sailing and rowing events are slated to be held in August of next year. Some athletes who plan to compete in the water events have voiced health and safety concerns over the waters.

The die-offs are becoming a common occurrence in Rio, where rivers, lakes and even the ocean are blighted by raw sewage and garbage. Officials have argued over the cause, with Rio’s environmental secretariat insisting last week that the incident is the result of the sudden change in water temperature.

“The intense rains that happened last week and a rise in the sea levels led to a spike in the [sea] water entering the lake, causing a thermal shock,” the secretariat said in a statement, adding that the water temperature had fallen by 7.2 degrees Fahrenheit in a short period of time.

Many scientists disagreed with that explanation, pointing to pollution instead.

The lake “has large concentrations of sulfur because of the organic material dumped into it, and depending on the winds, that material rises to the surface and kills fish,” said Estefan Monteiro de Fonseca, an oceanographer at the Fluminense Federal University.

Cristina Castelo Branco, an associate professor of aquatic ecology at the Federal University of Rio de Janeiro, also attributed the fish deaths to pollution, but in a different way.

Castelo Branco said that pollution from fertilizer, wastewater and storm-water runoff is affected by sunlight, warm temperature and slow-flowing water to produce algal blooms. The algae sucks out oxygen from the water, leading to fish deaths.

“This is a stressed lagoon. We have some problems with oxygen,” Castelo Branco told NPR.

Algal blooms have also caused toxicity levels to spike, which could harm people exposed to the lagoon’s waters, Castelo Branco added.

When toxicity is high, “you cannot swim in the lagoon in that situation,” she said.

Rio’s water quality has become one of the most contentious issues heading into the 2016 Olympics.

Authorities have long said that the games would be the catalyst for a major cleanup of the city’s waterways, but as the showcase sporting event approaches with few improvements, authorities are now admitting that many of the Olympic promises won’t be met.

Rio Governor Luiz Fernando Pezao acknowledged last week that “there’s not going to be time” to finish the cleanup ahead of the games, suggesting it might wrap up by the end of 2018 instead.

Fonesca, the oceanographer, warned that if another fish die-off occurs during the games, “Rio’s image could suffer irreparable damage.”

Aljazeera report.

Zimbabwe and Mozambique Discuss River Pollution.

Report by all Africa.com-Delegations from the Mozambican and Zimbabwean authorities met this week in the central city of Chimoio to discuss the pollution of international rivers caused by illegal artisanal gold mining, according to a report in Thursday’s issue of the Maputo daily “Noticias”.

The Revue and Pungoe rivers are being heavily polluted by mercury and other toxic substances used by the gold miners. There are two major dams on the Revue, at Chicamba and Mavuzi, and pollution by heavy metals raises questions about their future.

The rivers are also vital to drinking water supplies for Chimoio, Beira and other major urban centres in Manica and Sofala provinces. Mercury pollution is a serious threat to human health. The pollution can also have damaging effects on irrigation, agriculture and fish farming.

The purpose of the meeting was essentially to warn the Zimbabwean authorities, since most of the illegal gold miners are Zimbabwean, that the Manica provincial government is determined to eliminate illegal mining.

 Provincial governor Alberto Mondlane has made it clear that the levels of river pollution are intolerable, and the government must take measures against the illegal Zimbabwean miners. He wants to deport summarily all Zimbabweans involved in this activity.

“If there are only a few Mozambicans involved in this mining, why don’t we deport the foreigners who make up most of those carrying out this activity which is so damaging to the environment and to our economy?”, he asked.

“We should not suffer while we are capable of combating this problem”, he said. “There should be no tolerance for those who deliberately devastate our natural resources and the environment, and compete for our wealth”.

Last month, the police cracked down on illegal mining in the Chitunga area near the Zimbabwean border. 80 people were arrested, 76 of whom turned out to be Zimbabweans.

“Water shortages”, a disaster approaching faster than expected.

crazy world

worldwide crisis.

Water scarcity he lack of enough water (quantity) or lack of access to safe water (quality). Clean and  safe water is not something that can be taken for granted.

The problem of water scarcity is a growing one. As more people put ever increasing demands on limited supplies, the cost and effort to build or even maintain access to water will increase.

The new Constitution of Zimbabwe states in Chapter 4, Section 77 that: “Every person has the right to— safe, clean and portable water…” Water in Zimbabwe is a constitutional right.

Wilma Neels arguably says,”We need water to bath, we need water to drink (well, 70% of our bodies is made up of that clear liquid), we need water to push our sewer systems to their intended destinations; we need water to wash our clothes, we need water in the industries and cars as a coolant, and so forth and so on. The point is that we cannot do without water.”

boy-gathering-water-cirSurprisingly, the trend of water shortages equally plagues rural communities as they usually do not have access to clean water, if at all. In some southern parts of the country, stretching to the west, such as the Masvingo, Tsholotsho, Binga and Bulawayo provinces cases of perpetual shortages of water underscore the gravity and widespread nature of the water crisis in Zimbabwe.

The consequences are proving to be profound. Across the globe, reports reveal huge areas in crisis today as reservoirs and aquifers dry up. More than a billion individuals – one in seven people on the planet – now lack access to safe drinking water.

Yes this is happening and everyone can see it. the question is, can we watch it happening and do not take possible measures to reduce the crisis?. It is our mandate as a world to curb these problems before it is too late.

say a word and help serve our climate…

Gully Reclamation, a Priority.

gully 1

gully pulling its sox.

Soil erosion is a natural geomorphological process resulting from water erosion and land interactions but accelerated to become an environmental hazard by human activities such as clearing of forests for cultivation, poor farming practices and encroachment into marginal lands.

Environmental degradation has resulted from unsustainable population and livestock pressure over the more than fifty years of settlement in the area. This area was one of the areas where black people were resettled by the colonial regime under the land tenure system. The area already had poor sandy soils, is hot and experiences little annual rainfall and frequent droughts. It also has scanty vegetation cover. With increased population and livestock pressure on such areas, there has been extensive degradation resulting in formation of massive gullies in most areas.

gullyerosiondeccwbpeasley2a

Gullies can remove significant areas of land from high value cultivation. Photo: B. Peasley/DECCW

The most important aspect in preventing gully erosion is to maintain good ground cover. The combination of occasional heavy rainfall and a reduced ground cover caused by cropping, fire or high stocking rates result in most erosion damage.

Areas affected by extreme levels of gully erosion are best treated by changing the land use, sometimes in combination with minimal structural works. In some cases, the area surrounding the gullies must no longer be used for cropping or grazing, and must be allowed to revert to native vegetation. In other cases, it may be necessary to stop any further cultivation and keep the areas only for occasional grazing.

With Zimbabwe battling with poor economic conditions, there is need to engage citizens and be encouraged to preserve their own resources before the whole land turns into disarray. It has been notice that the majority have turned into farming and most of them have cleared lands in already degraded areas.

lets be cautious with our land use and help preserve it for our future generations.

Feeling for the future for kapenta.

images

fishing boats.

As economic meltdown looms in Zimbabwe, people around the country have resorted to invasion of little species (kapenta) in the Zambezi river. The rate at which fishermen are harvesting kapenta has raised eyebrows for the future of these species. The country is solely dependent on natural resources found locally and the few remaining resources are being utilised beyond control. The question to ask yourselves is, do people really see themselves in the future or are mourning to survive in the current situation?

for the betterment and smooth survival of our future generation, fish farming might be the best solution to sustain and see the growth of few resources we have in a long term.

The centre for kapenta fishing is Lake Kariba.This industry supplies kapenta to the country where it is eaten by a wide range of the local population and served as snacks and starters in hotels.

fish

harvested kapeta on display.

Visitors to Kariba may notice the many lights shining brightly on the lake at night from the kapenta fishing rigs, and be interested to know briefly how this fishery was formed. It was only in 1969 that substantial numbers were observed on the Zimbabwean side. Various experiments were undertaken by Lake Kariba Fisheries Institute in catching this fish, based on traditional techniques used on Lake Tanganyika. In 1973, however, the first commercial fishing enterprise formed, pioneering purse seine and square lift net techniques. Over the years, however, the dip net method has proved to be most productive, together with high-technology fish finders, hydraulic winches etc.

net

fish net.

local authorities must insure that dip nets are regulated and fishermen given the day and number of nets to use. this will eventually reduce the number of kapenta being out sourced every year. there should be given a breeding period for these species and ensure that all pieces are taken into consideration in the same way. 

How fishing is done is completely no mercy for the living organisms. dip nets are suspended from a boom on the rigs. They are fitted onto a 6 or 7meter diameter ring – conical in shape they are some 10 or 12 meters long. To commence fishing during darkness [kapenta are light attracted] the nets and underwater lights are lowered into the water and the overhead lights switched onto attract kapenta into the vicinity of the rig. 

After half an hour or so, the overhead lights are switched off to concentrate the shoal around the underwater light just above the net. The net is lifted at least three or four times during the night – more when the season is good.The kapenta thus caught are transferred into baskets and coarse salt added to maintain freshness. On return to harbour in the morning, the fish is placed onto drying racks where it is sun dried losing two thirds of its wet weight. This dried high protein product has the benefit of having a long ‘shelf life’and easily transported into remote areas without refrigeration.It is of interest to note that the size and life cycle of this species has adapted to harvesting over the years. Lake Kariba kapenta are smaller than their Lake Tanganyika brothers, reproducing at a smaller size and more frequently. Like grass – it grows better when cut.

without any remorse, fishermen are destroying the environment in which the future of the next generations remains in no men’s control.

lets conserve our environment, say a word and serve our planet.

River Rejuvination

220px-Bachalpseeflowers

swaziland mountains

LANDFORMS MADE BY RUNNING WATER Running Water is the most important single agent of denudation. Consequent Streams are initial stream that exist as a consequence of the slope. Insequent Stream are the tributary stream which joins the main stream (consequent Stream) obliquely.

Rejuvenation may result from causes which are dynamic, eustatic or isostatic in nature. All of these cause the river suddenly to erode its bed vertically (downcutting) faster as it gains gravitational potential energy. That causes effects such as meanders cut down as gorges, steps where the river suddenly starts flowing faster, and fluvial terraces derived from old floodplains.

riverMeanderDiagram

image showing a downcut

Incised meanders are meanders which are particularly well developed and occur when a river’s base level has fallen giving the river a large amount of vertical erosion power, allowing it to downcut.

There are two types of incised meanders, entrenched meanders and ingrown meanders. Entrenched meanders are symmetrical and form when the river downcuts particularly quickly. Due to the speed which the river downcuts, there is little opportunity for lateral erosion to occur giving them their symmetrical shape.

Ingrown meanders are asymmetrical. They form when the river downcuts at a less rapid pace, giving the river opportunity to erode laterally as well as vertically. A rejuvenating river can erode vertically into the former flood plain to produce features called river terraces. If vertical erosion is rapid then paired terraces are formed either side of the channel. If vertical erosion is slower though, unpaired terraces form as the river is given opportunity to meander. River terraces are particularly useful for settlements as they provide flat areas above the present floodplain. Oxford, Cambridge and London all developed on the river terraces of the Isis, Cam and Thames respectively.

Environmental impact of pesticides

300px-Hazardous-pesticide

Picture taken online

The environmental impact of pesticides consists of the effects of pesticides on non-target species. Over 98% of sprayed insecticides and 95% of herbicides reach a destination other than their target species, because they are sprayed or spread across entire agricultural fields. Runoff can carry pesticides into aquatic environments while wind can carry them to other fields, grazing areas, human settlements and undeveloped areas, potentially affecting other species. Other problems emerge from poor production, transport and storage practices. Over time, repeated application increases pest resistance, while its effects on other species can facilitate the pest’s resurgence.

Each pesticide or pesticide class comes with a specific set of environmental concerns. Such undesirable effects have led many pesticides to be banned, while regulations have limited and/or reduced the use of others. Over time, pesticides have generally become less persistent and more species-specific, reducing their environmental footprint. In addition the amounts of pesticides 300px-Drainage_nitrates_vers_HondeghemFr_2003_04_09applied per hectare have declined, in some cases by 99%. However, the global spread of pesticide use, including the use of older/obsolete pesticides that have been banned in some jurisdictions, has increased overall.

Farmers must be responsible in matters of reducing the risk of damage the environmental species. When ever an infection is noticed, responsible authorities must take maximum action on the perpetrators and help reduce the hazards.

drop your views about this effect and help rebuild our environment.