Skip to main content

Posts

Showing posts with the label salt

Jellyfish Numbers are Increasing Because of Humans

Jellyfish are spineless little devils. I do mean that in a good way. They are the most efficient swimmers on Earth, pulling their way forward rather than pushing. The "immortal jellyfish" rises phoenix-like from the dead. When it dies the decomposing body puts out stolon stalks which become babies. They are rapidly increasing in the world's oceans due mainly to Man. Most variations breed under man-made marine structures such as piers. The killing off of predatory fish for human food allows the transparent creatures to vastly increase in number. Cyaneidae have caused many problems over the years. Those going for a swim regularly get stung. In 2006 the seemingly invulnerable USS Ronald Reagan was put out of action by masses of jellyfish clogging the cooling system. Power plants and desalination facilities have also been stalled. Two million workers became unemployed when the comb jelly native to North America invaded the Black Sea in 1980 and destroyed anchovy...

Sharks Struggle in Freshwater

Sharks may seem to be invincible, yet they have some significant weaknesses. While some dolphins succumb to their attacks, acting as a group they can kill a shark by ramming it. Sharks also have to keep moving otherwise they die. Now it has been discovered that fresh water is their enemy. They get dehydrated and cannot remain alert. Breeding is out of the question in non-salty water. A terrific battle for survival ensues as sharks continually keep sinking. The reason for this is that sharks do not have air bladders. This "device" enables fish to swim at mid-depths. Sharks use their oily livers to stay afloat - very inefficient. They have to work 50 per cent harder when they leave the sea. Freshwater species of shark have refined the evolution of their livers. The organs are flatter than their ocean cousins. There is a penalty for a flatter liver. A fatter body means a less sleek body which makes river and estuary species slower. Even with fatter live...

Developing Australia's North is Just Pie in the Sky

The "opening-up" of northern Australia is pie in the sky by both leading political parties. Unless billions of dollars are put into the north development will not take place. The Ord River Irrigation Scheme is an example. However, the scheme is not a real success. Salinity is rising and destroying productive land. Are the political parties planning to build dams? No, not in new northern regions! Neither is putting forward substantial money for investment. Kevin Rudd's promise to extend the Ord River Dam will only drag up more salt. Just telling people to move north is a silly idea. Like the draw to Western Australia there must be financial incentives. The mining boom there means better paid jobs. Those suggesting development of northern Australia don't even study the climatic and geographic realities. Tropical soil is very thin. It barely covers the surface. To grow any plant in large quantities thick fertile soil is needed. Tropical soil may be fertile...