托福写作素材：种树保护环境
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While you probably think about planting trees for Arbor Day, you may not know just how much of an impact tree planting can have on your lawn and energy consumption as well as the environment.
Trees can provide shade for your home and lawn as well as a barrier against cold winter winds. They also filter water and air to reduce soil erosion and greenhouse gases. And did you know that trees have also been shown to reduce stress? Many urban residents find themselves calmer and happier when they are around trees.
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Energy-saving benefits of planting trees
According to the U.S. Department of Agriculture, a young, healthy tree can provide a net cooling effect equivalent to ten room-sized air conditioners operating for 20 hours a day! While it will take a few years for a newly planted sapling to reach the point where it can cast shade on your home, it’s a relatively low-cost investment, and you’ll find it’s worth the wait.
Dr. E. Greg McPherson of the Center for Urban Forest Research says that a new tree planted on the western side of your home will reduce your energy bill by about three percent in five years and by close to 12 percent in 15 years. Plus, shade isn’t the only way planting trees can reduce your family’s energy consumption. Trees located on the north and northwest sides of your home can block frigid winter winds and lower your heating bill.
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Benefit of trees on the environment
While planting trees can certainly have a positive impact on your energy bill, sustainable gardening can also positively impact the environment. Trees absorb greenhouse gases like nitrogen dioxide, sulfur dioxide, ozone, carbon dioxide and carbon monoxide. They also convert carbon dioxide to oxygen through photosynthesis. Wondering how that relates to you? Just one tree can clean about 330 pounds of carbon dioxide from the air each year, according to the U.S. Forest Service, which provides enough oxygen for a family of four!
One of the reasons planting new trees is seen as sustainable gardening is because they act as air and water filters. In a study conducted by the USDA, it was found that trees were able to remove more than 1,800 metric tons of air pollution from New York City. The roots filter groundwater and control run off and erosion by holding soil in place. They also cool down the air, and not just with shade. The transpiration process they go through releases moisture into the air, producing a cooling effect.
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Maintaining your trees and lawn
Trees are beneficial to the aesthetics of your lawn, your home’s energy bill, and your family’s overall health. For all these reasons, it’s important to properly maintain your trees and the soil they grow in. You don’t want to over-shape new trees or prune too much when you first plant them, but you will have a much healthier tree if you trim back dead branches over the years. There are several options when it comes to outdoor power equipment to maintain the trees you’ve planted. Chainsaws and pole saws are great choices for cutting down large limbs. They also work well for pruning, whether you need to allow for new growth or prevent branches from hitting obstacles like houses or power lines. There are even battery-operated, cordless saws available to reduce your carbon footprint even further.
The shade from the trees you’ve planted will help improve water conservation, so you’ll maintain a lush and green lawn with very little maintenance. However, you should still mow high and often, to avoid roots and promote new grass growth, being especially careful around the base of your trees. You may even want to spread mulch and compost to the drip line and maintain the edge with a string trimmer.
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