In places like California, the Rocky Mountains, and the Southern United States, wildfires are an unavoidable reality.
Wildfires can cause damage to property and human life, but they have many beneficial effects on native vegetation (植被), animals, and ecosystems that have evolved with fires. The forests, including pine barrens, lodgepole pine forests and many more, require fires to reproduce because the trees in the forest are adapted to only produce seeds following a major fire event. Therefore, without them many of these forest types would decline.
A fire renews the watershed (集水区) in ways including, but not limited to, recycling of nutrients, increasing food sources for fish in streams, supplement to streamside vegetation, spread of fire-adapted plants, etc. not to mention renewal of the soil chemistry which is vital to the forest and the watershed. The basis is that of someone who has studied wildfires and streams since the 1988 Yellowstone wildfires. The science backs up how natural wildfires can be favorable through research publication after publication.
It’s like “resetting the clock” on the ecosystem, allowing the forest to function smoothly all over again for another 200 years. By the way, a stand burning fire such as the Yellowstone fires of 1988 also results in the landscape of younger forest mends which act to reduce the spread of future wildfires and can stop a major wildfire in its tracks.
The bottom line is that we may need today’s natural wildfires to prevent more serious catastrophic fire events in the future. That lesson was learned in Yellowstone in 1988 which was a year of disastrous largescale fires after more than 50 years of fire suppression (压制).
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Most people all over the world travel by road. In a city in Italy, however, waterways makeup the primary commuting routes. The city of Venice is best known for its canals. Unfortunately, this beautiful city of flat-bottomed boats (Gondolas), and churches is sinking and sinking fast.
Known as the “Queen of the Adriatic”, Venice is situated on more than one hundred islands formed by canals between the mouths of the Po and Piave Rivers. And even the bits of firm ground have rather boggy foundations and all these are slowly getting eroded (腐蚀).
The existing groundwater table and the global climate changes that have raised sea levels by several inches, are proving its disaster for the city. As sea ice melts and water levels rise, floods in Venice are getting from bad to worse. And buildings are already feeling the impact of this phenomenon, with their foundations literally being shaken. Take one of the most famous landmarks of Venice for example, the St. Mark’s Basilica, now leans slightly to the left.
Experts warn that the city may sink an additional eight inches in the next 50 years. Many scared residents have already started to move to drier regions in Italy’s mainland. To deal with the flood threat, a group of Venetians, called the New Venice Consortium, has come up with “Project Moses”—a dam project named after the biblical figure, Moses. The idea is to place underwater gates at different points where the Adriatic Sea enters the lagoon (环礁湖). When the water is low, the gates will remain open and as the water rises, the gates will close, preventing the seawater from flooding Venice. However, some people disagree with this idea. Environ mentalists point out that the gates would have to remain closed most of the time and seawater will not be able to move in and out of Venice. As a result the lagoon water will become stagnant (停滞的), harming the fish and plants that live there. Until a viable (可实施的) solution is found out, Venice, it seems, would continue to be threatened by floods.
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Almost everyone has read about the Taj Mahal in India. It is one of the most beautiful buildings in the world. Over three hundred years ago, Shah Jehan built the Taj Mahal as the tomb for his wife. Shah Jehan wanted his wife's tomb to be perfect. He did not care about time or money. He brought together workmen from all Asia. Altogether, over 20,000 men worked on the building, and it took them over seventeen years to finish it.
The building rests on a platform of red sandstone. Four thin white towers rise from the corners of the platform. A large dome rests from the centre of the building. Around this large dome there are four smaller ones.
The building is made of fine white and coloured marble. It has eight sides and many arches. There is an open corridor just inside the outer walls. From this corridor, the visitor looks through the marble screen to a central room. The bodies of Shah Jehan and his wife lie in a tomb below this room.
A beautiful garden surrounds the Taj Mahal. The green trees make the marble look even whiter. In front of the main entrance to the building there is a long, narrow pool. If you look in this pool, you can see all the beauty of the Taj Mahal in the reflection from the water.
Many people think the Taj Mahal is the most beautiful at sunset. Then the marble picks up the colour of the sunset, and the building and its reflection in the pool gleam like red jewels.
