Mineral Depletion
Soil is the prime source of minerals on which every living cell depends for its structure and function. Vitamins, enzymes, amino acids (protein) and a host of other biologically active substances are essential for our bodies to function properly. They virtually all include minerals as an integral part of their chemical structure. Dr Linus Pauling, twice noble prize winner, said “you can trace every sickness, every disease and every ailment to a mineral deficiency”. Yet, all over the world, minerals are disappearing from agricultural soils at an alarming rate. In 1992, the official report of the Rio Earth Summit concluded “there is deep concern over continuing major declines in the mineral values in farm and range soils throughout the world”. This statement was based on data showing that over the last 100 years, average mineral levels in agricultural soils had fallen worldwide – by 72% in Europe, 76% in Asia and 85% in North America. What has caused this staggering decline?
Most of the blame lies with artificial chemical fertilisers. We now know that plants absorb 70 to 80 different minerals from the soil, while the number returned to it by plants grown with commercial fertilisers can be counted on the fingers of one hand. Every crop that is cut or animal that is sent to market marks a further depletion in the mineral status of the soil on which it was raised. Organic wastes that in former times would have been composted and returned to the land are nowadays mostly consigned to landfill sites or incineration.
There are many other ways in which the move to chemical farming prevents crops from taking up even the sparse amounts of trace minerals left in the soil. Soil contains bacteria, fungi, plant and animal life, in a state of constant interaction and balance. Every one of these organisms needs dozens of different minerals to survive and play its part in the ecosystem. Some bacteria have a vital role in converting soil minerals into chemical forms that plants can use. NPK fertilisers (fertilisers used in modern farming that only contain nitrogen, phosphorous and potassium) gradually change the soil pH towards acidic conditions in which these bacteria can not survive. To combat soil acidification farmers lay lime on the land adding back calcium and magnesium to raise the soil pH, but it also converts manganese and some other trace minerals into chemical forms that plants are unable to absorb.
Pesticides and herbicides also reduce the uptake of trace minerals by plants. Plants have an important relationship with certain fungi that can form networks covering several acres. The fungus obtains carbohydrates from the plant root, at the same time supplying the plant with nutrients it draws from the soil. This gives the plant access to a vastly greater mineral extraction system than is possible by their roots alone. Chemical fungicide sprays destroy these beneficial fungi and so again reduce the ability of plants to absorb soil minerals. Insecticides can also reduce trace mineral uptake by inactivating choline-containing enzymes in plants, essential for the absorption of manganese and other minerals.
The combined effect of soil mineral depletion and the reduced availability of those minerals that remain is that most of the food that we eat is mineral deficient. The table below summarizes the reductions in the average mineral content of 27 vegetables and 17 fruits, between 1940 and 1991. The results of the latest research are expected to show mineral values in continual decline.
A new study published earlier this year shows that, as might be expected, mineral levels in animal products reflect the picture in plant foods. Comparing levels measured in 2002 with those present in 1940, the iron content of milk was found to be 62% less, calcium and magnesium in parmesan cheese had each fallen by 70% and copper in dairy produce had plummeted by a remarkable 90%.
The UK government is putting resources into improving health by encouraging people to eat a healthy diet, including 5 portions of fruit and vegetables per day, but you scarcely hear a word about the problem of soil mineral depletion. Food seems to be considered as something quite separate from its source and means of production. But this is not rocket science – the foundation of human health is the quality of the food we eat, which relies ultimately on the vitality of the soil on which it is raised.
Minerals are needed for the proper formation of blood and bone, the maintenance of healthy nerve function, heartbeat regulation, reproduction and foetal development. They are essential to the process of growth, healing and energy release. And it is not just the presence of the mineral in the body that is important – they must be in the correct ratio to each other. The level of each mineral has an effect, directly or indirectly, on every other, so if one is out of kilter the whole system is affected.
Minerals are an essential part of our natural diet and a lack of them may in part account for our increasing susceptibility to the “diseases of civilisation” – such as heart disease (magnesium), cancer (selenium), diabetes (chromium) and mental illnesses (zinc). Every one of us should take care to get the minerals we need, for the good of our health.
Soil is the prime source of minerals on which every living cell depends for its structure and function. Vitamins, enzymes, amino acids (protein) and a host of other biologically active substances are essential for our bodies to function properly. They virtually all include minerals as an integral part of their chemical structure. Dr Linus Pauling, twice noble prize winner, said “you can trace every sickness, every disease and every ailment to a mineral deficiency”. Yet, all over the world, minerals are disappearing from agricultural soils at an alarming rate. In 1992, the official report of the Rio Earth Summit concluded “there is deep concern over continuing major declines in the mineral values in farm and range soils throughout the world”. This statement was based on data showing that over the last 100 years, average mineral levels in agricultural soils had fallen worldwide – by 72% in Europe, 76% in Asia and 85% in North America. What has caused this staggering decline?
Most of the blame lies with artificial chemical fertilisers. We now know that plants absorb 70 to 80 different minerals from the soil, while the number returned to it by plants grown with commercial fertilisers can be counted on the fingers of one hand. Every crop that is cut or animal that is sent to market marks a further depletion in the mineral status of the soil on which it was raised. Organic wastes that in former times would have been composted and returned to the land are nowadays mostly consigned to landfill sites or incineration.
There are many other ways in which the move to chemical farming prevents crops from taking up even the sparse amounts of trace minerals left in the soil. Soil contains bacteria, fungi, plant and animal life, in a state of constant interaction and balance. Every one of these organisms needs dozens of different minerals to survive and play its part in the ecosystem. Some bacteria have a vital role in converting soil minerals into chemical forms that plants can use. NPK fertilisers (fertilisers used in modern farming that only contain nitrogen, phosphorous and potassium) gradually change the soil pH towards acidic conditions in which these bacteria can not survive. To combat soil acidification farmers lay lime on the land adding back calcium and magnesium to raise the soil pH, but it also converts manganese and some other trace minerals into chemical forms that plants are unable to absorb.
Pesticides and herbicides also reduce the uptake of trace minerals by plants. Plants have an important relationship with certain fungi that can form networks covering several acres. The fungus obtains carbohydrates from the plant root, at the same time supplying the plant with nutrients it draws from the soil. This gives the plant access to a vastly greater mineral extraction system than is possible by their roots alone. Chemical fungicide sprays destroy these beneficial fungi and so again reduce the ability of plants to absorb soil minerals. Insecticides can also reduce trace mineral uptake by inactivating choline-containing enzymes in plants, essential for the absorption of manganese and other minerals.
The combined effect of soil mineral depletion and the reduced availability of those minerals that remain is that most of the food that we eat is mineral deficient. The table below summarizes the reductions in the average mineral content of 27 vegetables and 17 fruits, between 1940 and 1991. The results of the latest research are expected to show mineral values in continual decline.
A new study published earlier this year shows that, as might be expected, mineral levels in animal products reflect the picture in plant foods. Comparing levels measured in 2002 with those present in 1940, the iron content of milk was found to be 62% less, calcium and magnesium in parmesan cheese had each fallen by 70% and copper in dairy produce had plummeted by a remarkable 90%.
The UK government is putting resources into improving health by encouraging people to eat a healthy diet, including 5 portions of fruit and vegetables per day, but you scarcely hear a word about the problem of soil mineral depletion. Food seems to be considered as something quite separate from its source and means of production. But this is not rocket science – the foundation of human health is the quality of the food we eat, which relies ultimately on the vitality of the soil on which it is raised.
Minerals are needed for the proper formation of blood and bone, the maintenance of healthy nerve function, heartbeat regulation, reproduction and foetal development. They are essential to the process of growth, healing and energy release. And it is not just the presence of the mineral in the body that is important – they must be in the correct ratio to each other. The level of each mineral has an effect, directly or indirectly, on every other, so if one is out of kilter the whole system is affected.
Minerals are an essential part of our natural diet and a lack of them may in part account for our increasing susceptibility to the “diseases of civilisation” – such as heart disease (magnesium), cancer (selenium), diabetes (chromium) and mental illnesses (zinc). Every one of us should take care to get the minerals we need, for the good of our health.
Deforestation
Philippines Forest Figures
------------------------------------------------------------------
Forest CoverTotal forest area: 7,162,000 ha
% of land area: 24%
------------------------------------------------------------------
Primary forest cover: 829,000 ha
% of land area: 2.8%
% total forest area: 11.6%
------------------------------------------------------------------
Deforestation Rates, 2000-2005Annual change in forest cover: -157,400 ha
Annual deforestation rate: -2.1%
Change in defor. rate since '90s: -20.2%
Total forest loss since 1990: -3,412,000 ha
Total forest loss since 1990:-32.3%
------------------------------------------------------------------
Primary or "Old-growth" forests
Annual loss of primary forests: n/a
Annual deforestation rate: n/a
Change in deforestation rate since '90s: n/a
Primary forest loss since 1990: n/a
Primary forest loss since 1990:0.0%
------------------------------------------------------------------
Forest ClassificationPublic: 89.5%
Private: 10.5%
Other: n/a
Use
Production: 75%
Protection: 11%
Conservation: 12%
Social services: n/a
Multiple purpose: n/a
None or unknown: 2
------------------------------------------------------------------
Forest Area BreakdownTotal area: 7,162,000 ha
Primary: 829,000 ha
Modified natural: 5,713,000 ha
Semi-natural: n/a
Production plantation: 304,000 ha
Production plantation: 316,000 ha
------------------------------------------------------------------
PlantationsPlantations, 2005: 620,000 ha
% of total forest cover: 8.7%
Annual change rate (00-05): -46,400,000 ha
------------------------------------------------------------------
Carbon storageAbove-ground biomass: 1,566 M t
Below-ground biomass: 376 M t
------------------------------------------------------------------
Area annually affected byFire: 6,000 ha
Insects: n/a
Diseases: 1,000 ha
------------------------------------------------------------------
Number of tree species in IUCN red listNumber of native tree species: 3,000
Critically endangered: 46
Endangered: 35
Vulnerable: 134
------------------------------------------------------------------
Wood removal 2005Industrial roundwood: 403,000 m3 o.b.
Wood fuel: 138,000 m3 o.b.
------------------------------------------------------------------
Value of forest products, 2005Industrial roundwood: $60,272,000
Wood fuel: $722,000
Non-wood forest products (NWFPs): n/a
Total Value: $60,994,000
------------------------------------------------------------------
Almost two decades after the Catholic Church leaders warned against an ecological debacle in the country, the disappearance of forests remains. Between 1990 and 2005, the Philippines lost one-third of its forest cover. The current deforestation rate is around 2% per year, a 20 % drop from the rate of the 1990s.
“No one says there is an increase in real forest cover in the Philippines. Maybe there is an increase in the number of trees, but it is not the forest we idealize, romanticize, log or even live in,” says Peter Walpole, executive director of the Ateneo de Manila University's Environmental Science for Social Change. “We have lost most of our forest of hold over the past 50 years and, along with them, many of the ecological services they provide.”
According to the Department of Environment and Natural Resources (DENR), the principal cause of the decimation of the country’s forest cover are logging (both legal and illegal), shifting cultivation (locally known as kaingin), forest fires, natural calamities (like earthquake),
as well as conversion to agricultural lands, human settlements and other land uses brought about by urbanization and increasing population pressure.
“Deforestation is a symptom of a bigger problem,” says Nicolo del Castillo, an architect by profession who teaches at the University of the Philippines. “ I probably sound tacky and outdated, but I see the problem in the prevailing system of values, that is, the greed, the need to be the biggest, the wealthiest, and sometimes you feel hopeless. I am an optimist, but possibly there will be more tragedies and maybe then more people will wake up.”
The removal of forest cover makes the Philippines susceptible to various environmental catastrophes. “Most of these were not seen in such intensity and magnitude before our time,” deplored Roy C. Alimoane, the current director of the Davao-based Mindanao Baptist Rural Life Center Foundation, Inc. “The signs cry out for immediate, nationwide attention.”
Deforestation has been increasingly blamed for soil erosion. Although not considered a serious threat, it is an unseen scourge. “Soil erosion is an enemy to any nation – far worse than any outside enemy into a country and conquering it because it is an enemy you cannot see vividly," warned Harold R. Watson, an American agriculturist who received a Ramon Magsaysay Award in 1985 for peace and international understanding. “It’s a slow creeping enemy that soon possesses the land.”
At least two provinces – Cebu and Batangas – have lost more than 80% of their topsoil to erosion. In Luzon, four major basins --- Bicol, Magat, Pampanga, and Agno – are in critical condition due to acute soil erosion and sedimentation.
The rampant cutting of trees has also significantly reduced the volume of groundwater available for domestic purposes. “If the forest perishes, so will the life of people,” said Diosmedes Demit, one of the farmers who joined the ‘Fast for the Forests’ in 1989. “The trees are our source of life. Without trees, there will be no water. If there is no water, there will be no life.”
Cebu, which has zero forest cover, is 99% dependent on groundwater. As a result, more than half of the towns and cities in Cebu, excluding Metro Cebu, have no access to potable water. In Metro Manila, where there are no forests to speak of, the water tables are being drawn at the rate of six to 12 meters a year causing saline water intrusion along the coastal areas.
Deforestation also brings too much water – in case of constant rain. “Rain which falls over a bare slope acts differently,” Gifford Pinchot wrote in A Primer for Forestry. “It is not caught by the crowns nor held by the floor, nor is its flow into the streams hindered by the timber. The result is that a great deal of water reaches the streams in a short time, which is the reason why floods occur.”
Remember the Ormoc tragedy in Leyte? More than five thousand people were reported to have perished from flash foods, injuring 292 others with 1,264 missing. The reported total cost of damage was P1.044 billion.
Deforestation also threatens the country’s wildlife resources. Two particular species of animals, the tamaraw and the Philippines eagle are almost extinct due to the massive deforestation. More than half the birds, amphibians and mammals endemic to the Philippines are threatened with extinction.
DENR’s Joselito Atienza said that 592 of the 1,137 species of amphibians, birds and mammals found only in the Philippines are considered “threatened or endangered.” Some 227 endemic species of plants are “critically endangered.”
Dr. Lee Talbot, former director of Southeast Asia Project on Wildlife Conservation of Nature and Natural Resources, issued this sober thought: “A few decades ago, the wildlife of the Philippines was notable for its abundance; now, it is notable for its variety. If present trend of destruction continues, Philippine wildlife will be notable for its absence.”
Deforestation has also altered the climatic condition in the country. Ask Father Jesus Ramon Villarin, a Jesuit scientist, who localized the global climate issue by exploring rainfall patterns in Mindanao in the last 50 years and the impact on crop production and the supply of freshwater resources.
This was what Father Villarin, who used to work with the Manila Observatory, has found: Rainfall over the northern coast of Mindanao has generally increased over the decades, with the northeast section receiving most of the increase. But the southern regions are experiencing decreasing rainfall, mostly in the south central parts.
Heherson Alvarez, who was formerly head of the environment department, once commented that if deforestation is not soon curbed, time would come that “we will be traveling to Manila and around Central Luzon by bancas (outriggers).”
Ben Malayang III, president of Silliman State University, commented: “That the forest, the foundations of our forests, or whatever forests remain in the country, is not a matter of technical forestry, but rather a symptom, or an indication, or a measure, of the failure of our political and social systems.”
Philippines Forest Figures
------------------------------------------------------------------
Forest CoverTotal forest area: 7,162,000 ha
% of land area: 24%
------------------------------------------------------------------
Primary forest cover: 829,000 ha
% of land area: 2.8%
% total forest area: 11.6%
------------------------------------------------------------------
Deforestation Rates, 2000-2005Annual change in forest cover: -157,400 ha
Annual deforestation rate: -2.1%
Change in defor. rate since '90s: -20.2%
Total forest loss since 1990: -3,412,000 ha
Total forest loss since 1990:-32.3%
------------------------------------------------------------------
Primary or "Old-growth" forests
Annual loss of primary forests: n/a
Annual deforestation rate: n/a
Change in deforestation rate since '90s: n/a
Primary forest loss since 1990: n/a
Primary forest loss since 1990:0.0%
------------------------------------------------------------------
Forest ClassificationPublic: 89.5%
Private: 10.5%
Other: n/a
Use
Production: 75%
Protection: 11%
Conservation: 12%
Social services: n/a
Multiple purpose: n/a
None or unknown: 2
------------------------------------------------------------------
Forest Area BreakdownTotal area: 7,162,000 ha
Primary: 829,000 ha
Modified natural: 5,713,000 ha
Semi-natural: n/a
Production plantation: 304,000 ha
Production plantation: 316,000 ha
------------------------------------------------------------------
PlantationsPlantations, 2005: 620,000 ha
% of total forest cover: 8.7%
Annual change rate (00-05): -46,400,000 ha
------------------------------------------------------------------
Carbon storageAbove-ground biomass: 1,566 M t
Below-ground biomass: 376 M t
------------------------------------------------------------------
Area annually affected byFire: 6,000 ha
Insects: n/a
Diseases: 1,000 ha
------------------------------------------------------------------
Number of tree species in IUCN red listNumber of native tree species: 3,000
Critically endangered: 46
Endangered: 35
Vulnerable: 134
------------------------------------------------------------------
Wood removal 2005Industrial roundwood: 403,000 m3 o.b.
Wood fuel: 138,000 m3 o.b.
------------------------------------------------------------------
Value of forest products, 2005Industrial roundwood: $60,272,000
Wood fuel: $722,000
Non-wood forest products (NWFPs): n/a
Total Value: $60,994,000
------------------------------------------------------------------
Almost two decades after the Catholic Church leaders warned against an ecological debacle in the country, the disappearance of forests remains. Between 1990 and 2005, the Philippines lost one-third of its forest cover. The current deforestation rate is around 2% per year, a 20 % drop from the rate of the 1990s.
“No one says there is an increase in real forest cover in the Philippines. Maybe there is an increase in the number of trees, but it is not the forest we idealize, romanticize, log or even live in,” says Peter Walpole, executive director of the Ateneo de Manila University's Environmental Science for Social Change. “We have lost most of our forest of hold over the past 50 years and, along with them, many of the ecological services they provide.”
According to the Department of Environment and Natural Resources (DENR), the principal cause of the decimation of the country’s forest cover are logging (both legal and illegal), shifting cultivation (locally known as kaingin), forest fires, natural calamities (like earthquake),
as well as conversion to agricultural lands, human settlements and other land uses brought about by urbanization and increasing population pressure.“Deforestation is a symptom of a bigger problem,” says Nicolo del Castillo, an architect by profession who teaches at the University of the Philippines. “ I probably sound tacky and outdated, but I see the problem in the prevailing system of values, that is, the greed, the need to be the biggest, the wealthiest, and sometimes you feel hopeless. I am an optimist, but possibly there will be more tragedies and maybe then more people will wake up.”
The removal of forest cover makes the Philippines susceptible to various environmental catastrophes. “Most of these were not seen in such intensity and magnitude before our time,” deplored Roy C. Alimoane, the current director of the Davao-based Mindanao Baptist Rural Life Center Foundation, Inc. “The signs cry out for immediate, nationwide attention.”
Deforestation has been increasingly blamed for soil erosion. Although not considered a serious threat, it is an unseen scourge. “Soil erosion is an enemy to any nation – far worse than any outside enemy into a country and conquering it because it is an enemy you cannot see vividly," warned Harold R. Watson, an American agriculturist who received a Ramon Magsaysay Award in 1985 for peace and international understanding. “It’s a slow creeping enemy that soon possesses the land.”
At least two provinces – Cebu and Batangas – have lost more than 80% of their topsoil to erosion. In Luzon, four major basins --- Bicol, Magat, Pampanga, and Agno – are in critical condition due to acute soil erosion and sedimentation.
The rampant cutting of trees has also significantly reduced the volume of groundwater available for domestic purposes. “If the forest perishes, so will the life of people,” said Diosmedes Demit, one of the farmers who joined the ‘Fast for the Forests’ in 1989. “The trees are our source of life. Without trees, there will be no water. If there is no water, there will be no life.”
Cebu, which has zero forest cover, is 99% dependent on groundwater. As a result, more than half of the towns and cities in Cebu, excluding Metro Cebu, have no access to potable water. In Metro Manila, where there are no forests to speak of, the water tables are being drawn at the rate of six to 12 meters a year causing saline water intrusion along the coastal areas.
Deforestation also brings too much water – in case of constant rain. “Rain which falls over a bare slope acts differently,” Gifford Pinchot wrote in A Primer for Forestry. “It is not caught by the crowns nor held by the floor, nor is its flow into the streams hindered by the timber. The result is that a great deal of water reaches the streams in a short time, which is the reason why floods occur.”
Remember the Ormoc tragedy in Leyte? More than five thousand people were reported to have perished from flash foods, injuring 292 others with 1,264 missing. The reported total cost of damage was P1.044 billion.
Deforestation also threatens the country’s wildlife resources. Two particular species of animals, the tamaraw and the Philippines eagle are almost extinct due to the massive deforestation. More than half the birds, amphibians and mammals endemic to the Philippines are threatened with extinction.
DENR’s Joselito Atienza said that 592 of the 1,137 species of amphibians, birds and mammals found only in the Philippines are considered “threatened or endangered.” Some 227 endemic species of plants are “critically endangered.”
Dr. Lee Talbot, former director of Southeast Asia Project on Wildlife Conservation of Nature and Natural Resources, issued this sober thought: “A few decades ago, the wildlife of the Philippines was notable for its abundance; now, it is notable for its variety. If present trend of destruction continues, Philippine wildlife will be notable for its absence.”
Deforestation has also altered the climatic condition in the country. Ask Father Jesus Ramon Villarin, a Jesuit scientist, who localized the global climate issue by exploring rainfall patterns in Mindanao in the last 50 years and the impact on crop production and the supply of freshwater resources.
This was what Father Villarin, who used to work with the Manila Observatory, has found: Rainfall over the northern coast of Mindanao has generally increased over the decades, with the northeast section receiving most of the increase. But the southern regions are experiencing decreasing rainfall, mostly in the south central parts.
Heherson Alvarez, who was formerly head of the environment department, once commented that if deforestation is not soon curbed, time would come that “we will be traveling to Manila and around Central Luzon by bancas (outriggers).”
Ben Malayang III, president of Silliman State University, commented: “That the forest, the foundations of our forests, or whatever forests remain in the country, is not a matter of technical forestry, but rather a symptom, or an indication, or a measure, of the failure of our political and social systems.”
Coral Bleaching
Ten percent of the world's reefs have been completely destroyed. In the Philippines, where coral reef destruction is the worst, over 70% have been destroyed and only 5% can be said to be in good condition. What has happened to destroy all of the reefs? Humans have happened.
There are two different ways in which humans have contributed to the degradation of the Earth's coral reefs, i
ndirectly and directly. Indirectly, we have destroyed their environment. As you read earlier, coral reefs can live only within a certain temperature and salinity range. Global warming caused by the green house effect has raised the temperature of the oceans so high that the coral get sick and die. Even a rise of one degree in the average water temperature can hurt the coral. Due to global warming, 1998 was the hottest year in the last six centuries and 1998 was the worst year for coral.
The most obvious sign that coral is sick is coral bleaching. That is when either the algae inside die, or the algae leave the coral. The algae are what give coral its color, so without the algae the coral has no color and the white of the limestone shell shines through the transparent coral bodies. People have been noticing coral bleaching since the turn of the century, but only since the 1980s has it gotten really bad.
The warmer water also encourages the growth of harmful algae on top of the coral, which kills it, because it blocks out the sun. Without the sun, the zooxanthellae cannot perform photosynthesis and so they die. Without the zooxanthellae, the coral polyps die too. This algae is usually eaten by fish, but because of over fishing, there aren't enough fish left to eat all the algae. And the pollution we dump in the ocean is just what the algae needs to grow and be healthy, which means covering and eventually killing the coral reefs.
The direct way in which humans destroy coral reefs is by physically killing them. All over the world, but especially in the Philippines, divers catch the fish that live in and around coral reefs. They sell these fish to fancy restaurants in Asia and to fancy pet stores in the United States. This would be OK if the divers caught the fish carefully with nets and didn't hurt the reefs or take too many fish. But the divers want lots of fish and most of them are not very well trained at fish catching. Often they blow up a coral reef with explosives (picture below) and then catch all the stunned fish swimming around. This completely destroys the reefs, killing the coral polyps that make it as well as many of the plants and animals that call it home. And the creatures that do survive are left homeless.
Another way that divers catch coral reef fish is with cyanide. Cyanide is a poison. The divers pour this poison on the reef, which stuns the fish and kills the coral. Then they rip open the reef with crowbars and catch the fish while they are too sick from the poison to swim away. This poison kills 90% of the fish that live in the reef and the reef is completely destroyed both by the poison and then by being ripped apart.
All this may seem a bit depressing, but there are many groups in the world dedicated to saving the coral reefs. These groups work to educate people about the destruction of coral reefs. They lobby the United States Congress as well as the governments of other nations, trying to convince them not to buy fish that have been caught by destroying coral reefs. They encourage governments to crack down on pollution, both into the ocean and into the air, which causes global warming. They encourage visitors to coral reefs to be careful not to harm them. They even build artificial reefs to replace the reefs that have been destroyed. If you want to learn more about these groups, visit some of their websites, like the Coral Reef Alliance, Reef Relief, and the Planetary Coral Reef Foundation.
Some people help coral reefs by convincing governments to treat them with care. Other people help coral reefs by studying them. One way that people learn more about coral reefs is by slicing open dead ones and looking inside. The inside of a coral reef looks a lot like the inside of a tree (picture below) and the lines mean the same thing. A person who studies tree rings is called a dendrochronologist. " Dendro " means tree, " chron " means time and " ologist " means person who studies, so dendrochronologist means person who studies trees through time. Dendrochronologists count the number of rings in a slice of a tree to see how old the tree was when it died. There is one ring for each year the tree lived. The dendrochronologist also looks at the size of the rings. A thick ring means that that year there was lots of food and it was a good year for the tree. A thin ring can mean that there was a drought that year or maybe the tree was sick. In the same way, oceanographers can look at the rings in a slice of coral and see how old the coral is and which years were good years and which were not. The more we know about coral the better we will be able to protect them for years to come.
Ten percent of the world's reefs have been completely destroyed. In the Philippines, where coral reef destruction is the worst, over 70% have been destroyed and only 5% can be said to be in good condition. What has happened to destroy all of the reefs? Humans have happened.
There are two different ways in which humans have contributed to the degradation of the Earth's coral reefs, i
ndirectly and directly. Indirectly, we have destroyed their environment. As you read earlier, coral reefs can live only within a certain temperature and salinity range. Global warming caused by the green house effect has raised the temperature of the oceans so high that the coral get sick and die. Even a rise of one degree in the average water temperature can hurt the coral. Due to global warming, 1998 was the hottest year in the last six centuries and 1998 was the worst year for coral.The most obvious sign that coral is sick is coral bleaching. That is when either the algae inside die, or the algae leave the coral. The algae are what give coral its color, so without the algae the coral has no color and the white of the limestone shell shines through the transparent coral bodies. People have been noticing coral bleaching since the turn of the century, but only since the 1980s has it gotten really bad.
The warmer water also encourages the growth of harmful algae on top of the coral, which kills it, because it blocks out the sun. Without the sun, the zooxanthellae cannot perform photosynthesis and so they die. Without the zooxanthellae, the coral polyps die too. This algae is usually eaten by fish, but because of over fishing, there aren't enough fish left to eat all the algae. And the pollution we dump in the ocean is just what the algae needs to grow and be healthy, which means covering and eventually killing the coral reefs.
The direct way in which humans destroy coral reefs is by physically killing them. All over the world, but especially in the Philippines, divers catch the fish that live in and around coral reefs. They sell these fish to fancy restaurants in Asia and to fancy pet stores in the United States. This would be OK if the divers caught the fish carefully with nets and didn't hurt the reefs or take too many fish. But the divers want lots of fish and most of them are not very well trained at fish catching. Often they blow up a coral reef with explosives (picture below) and then catch all the stunned fish swimming around. This completely destroys the reefs, killing the coral polyps that make it as well as many of the plants and animals that call it home. And the creatures that do survive are left homeless.
Another way that divers catch coral reef fish is with cyanide. Cyanide is a poison. The divers pour this poison on the reef, which stuns the fish and kills the coral. Then they rip open the reef with crowbars and catch the fish while they are too sick from the poison to swim away. This poison kills 90% of the fish that live in the reef and the reef is completely destroyed both by the poison and then by being ripped apart.
All this may seem a bit depressing, but there are many groups in the world dedicated to saving the coral reefs. These groups work to educate people about the destruction of coral reefs. They lobby the United States Congress as well as the governments of other nations, trying to convince them not to buy fish that have been caught by destroying coral reefs. They encourage governments to crack down on pollution, both into the ocean and into the air, which causes global warming. They encourage visitors to coral reefs to be careful not to harm them. They even build artificial reefs to replace the reefs that have been destroyed. If you want to learn more about these groups, visit some of their websites, like the Coral Reef Alliance, Reef Relief, and the Planetary Coral Reef Foundation.
Some people help coral reefs by convincing governments to treat them with care. Other people help coral reefs by studying them. One way that people learn more about coral reefs is by slicing open dead ones and looking inside. The inside of a coral reef looks a lot like the inside of a tree (picture below) and the lines mean the same thing. A person who studies tree rings is called a dendrochronologist. " Dendro " means tree, " chron " means time and " ologist " means person who studies, so dendrochronologist means person who studies trees through time. Dendrochronologists count the number of rings in a slice of a tree to see how old the tree was when it died. There is one ring for each year the tree lived. The dendrochronologist also looks at the size of the rings. A thick ring means that that year there was lots of food and it was a good year for the tree. A thin ring can mean that there was a drought that year or maybe the tree was sick. In the same way, oceanographers can look at the rings in a slice of coral and see how old the coral is and which years were good years and which were not. The more we know about coral the better we will be able to protect them for years to come.
PHILIPPINES MANGROVE ECOSYSTEM & BIODIVERSITY
Mangroves - are salt-tolerant, woody, seed-bearing plants that are found in tropical and subtropical areas where they are subject to periodic tidal inundation. The Philippines has over 40 species of mangroves and is one of the most biodiverse regions in the world as there are only about 70 species of mangroves worldwide. The mangrove ecosystem is a very diverse one and is home to many birds, fish, mammals, crustaceans and other animals.
ROOT SYSTEM
Mangroves are very specialized plants and have adapted to survive in a very harsh environment where other plants cannot survive. An example of an interesting adaptation is the root system of mangroves. Since mangroves often live in muddy environments where gas exchange is difficult, the root systems of many mangrove species are highly specialized. One example of this is pneumatophores or breathing roots which look like fingers sticking out of the ground which are seen on Avicennia spp. (api-api) and Sonneratia spp. (pagatpat) trees. Other roots which grow out from branches and the trunk of mangrove trees such as those on Rhizophora spp. (bakaun) are called stilt or prop roots. These roots contain lenticels or breathing holes which allow gas exchange above the ground. These stilt roots also provide support and anchorage during high winds and wave action as well as serving as an attachment substrate for many marine organisms. Other species have knee or knob roots above the ground such as seen in Busain.
ADAPTATIONS: EXCRETERS/EXCLUDERS
Mangroves must also deal with the saltwater environment that they live in. While many mangrove trees grow best in a mixture of saltwater, an excessive amount of salt would certainly kill them. In order to deal with this mangrove species have developed a number of different adaptations. Certain trees such as api-api are excreters and they expel salt crystals from their leaves which is then washed away by the rain. Others are excluders and block salt from entering through their roots. They accomplish this by having a high innate concentration of salt in their roots which prevents water from entering against the osmotic gradient. Other plants are secluders which concentrate salt in certain leaves which turn yellow and die and expel the salt when these leaves die.
PROPAGULES
Mangroves also have adapted certain reproductive mechanisms to deal with the harsh salt water environment. One of these is the viviparous propagule or tungki found on bakuan. This propagule is already germinated on the tree and has a basic stem structure and can therefore easily be implanted in the substrate and quickly begin to grow. If the propagule does however fall in the water it has the ability to float for up to one year which aids greatly in dispersal of mangrove species.
FOOD FOR MARINE ORGANISMS
Mangroves provide an important nursery for fish, shellfish and other organisms. It is estimated that each hectare of mangrove produces 3,600 kg of litterfall which provides food for 1,000 kg of marine organisms. With the abundance of food for fish present in the mangroves, each year one hectare of forest yields 283.5 metric tons of fish per year. Mangroves also provide other important functions such as preventing soil erosion and protecting shoreline from typhoons and strong waves. Mangroves provide many other products and services such as medicines, alcohol, housing materials and are an area for research and tourism.
THREATS
Even with all of these known benefits the state of mangroves within the Philippines is very dim. In the early 1900’s there were approximately 500,000 hectares of mangroves but today there are only about 120,000 hectares. Many of the mangrove areas were destroyed to make way for fishponds and reclamation areas. They were used indiscriminately for housing materials and were disturbed by siltation and pollution. Now that the true benefit of these ecosystems is known there is protection and rehabilitation of these important ecosystems. It is now illegal to cut down mangroves for any purpose and local governments and community organizations have taken active roles in planting and managing mangrove plantations. There is hope that in the future mangroves will return to the healthy status that they once held in the past.
Mangroves - are salt-tolerant, woody, seed-bearing plants that are found in tropical and subtropical areas where they are subject to periodic tidal inundation. The Philippines has over 40 species of mangroves and is one of the most biodiverse regions in the world as there are only about 70 species of mangroves worldwide. The mangrove ecosystem is a very diverse one and is home to many birds, fish, mammals, crustaceans and other animals.
ROOT SYSTEM
Mangroves are very specialized plants and have adapted to survive in a very harsh environment where other plants cannot survive. An example of an interesting adaptation is the root system of mangroves. Since mangroves often live in muddy environments where gas exchange is difficult, the root systems of many mangrove species are highly specialized. One example of this is pneumatophores or breathing roots which look like fingers sticking out of the ground which are seen on Avicennia spp. (api-api) and Sonneratia spp. (pagatpat) trees. Other roots which grow out from branches and the trunk of mangrove trees such as those on Rhizophora spp. (bakaun) are called stilt or prop roots. These roots contain lenticels or breathing holes which allow gas exchange above the ground. These stilt roots also provide support and anchorage during high winds and wave action as well as serving as an attachment substrate for many marine organisms. Other species have knee or knob roots above the ground such as seen in Busain.
ADAPTATIONS: EXCRETERS/EXCLUDERS
Mangroves must also deal with the saltwater environment that they live in. While many mangrove trees grow best in a mixture of saltwater, an excessive amount of salt would certainly kill them. In order to deal with this mangrove species have developed a number of different adaptations. Certain trees such as api-api are excreters and they expel salt crystals from their leaves which is then washed away by the rain. Others are excluders and block salt from entering through their roots. They accomplish this by having a high innate concentration of salt in their roots which prevents water from entering against the osmotic gradient. Other plants are secluders which concentrate salt in certain leaves which turn yellow and die and expel the salt when these leaves die.
PROPAGULES
Mangroves also have adapted certain reproductive mechanisms to deal with the harsh salt water environment. One of these is the viviparous propagule or tungki found on bakuan. This propagule is already germinated on the tree and has a basic stem structure and can therefore easily be implanted in the substrate and quickly begin to grow. If the propagule does however fall in the water it has the ability to float for up to one year which aids greatly in dispersal of mangrove species.
FOOD FOR MARINE ORGANISMS
Mangroves provide an important nursery for fish, shellfish and other organisms. It is estimated that each hectare of mangrove produces 3,600 kg of litterfall which provides food for 1,000 kg of marine organisms. With the abundance of food for fish present in the mangroves, each year one hectare of forest yields 283.5 metric tons of fish per year. Mangroves also provide other important functions such as preventing soil erosion and protecting shoreline from typhoons and strong waves. Mangroves provide many other products and services such as medicines, alcohol, housing materials and are an area for research and tourism.
THREATS
Even with all of these known benefits the state of mangroves within the Philippines is very dim. In the early 1900’s there were approximately 500,000 hectares of mangroves but today there are only about 120,000 hectares. Many of the mangrove areas were destroyed to make way for fishponds and reclamation areas. They were used indiscriminately for housing materials and were disturbed by siltation and pollution. Now that the true benefit of these ecosystems is known there is protection and rehabilitation of these important ecosystems. It is now illegal to cut down mangroves for any purpose and local governments and community organizations have taken active roles in planting and managing mangrove plantations. There is hope that in the future mangroves will return to the healthy status that they once held in the past.
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