• Plants produce both food and oxygen for people and animals, among other benefits.Thomas Northcut/Photodisc/Getty Images
  
  Underfoot and overhead, plants shape and color the landscapes around you, adding both beauty and definition. A landscape without plants and trees often looks barren, empty and ugly. Plants, however, serve purposes beyond the beauty and comfort they provide. As more and more plants disappear to make room for human development, their declining populations could have a negative impact.
  
  

Less Oxygen

• In order to produce energy, plants take in carbon dioxide from the air and, using water and light from the sun, convert it into sugar. Oxygen remains as a leftover in this process, so plants release it back into the atmosphere, where it becomes available for humans and animals to use. The ability of plants to both take in carbon dioxide and produce oxygen proves vital to life on Earth. In the rainforests alone, the Rainforest Coalition estimates that plants produce 20 percent of the world's oxygen. When cutting down or destroying plants, carbon dioxide remains in the atmosphere, and oxygen levels drop.
  
  

Higher Energy Costs

• Trees around your home provide the shade needed to keep it cool in the summer and reduce reliance on air conditioning and other energy-draining appliances. In the winter, trees block the cold winter winds that make your home heating system have to work harder. Quoting Dr. E. Greg McPherson of the Center for Urban Forest Research, the Arbor Day Foundation states that a single tree planted on the west side of your home will drop your energy costs 12 percent in 15 years. Removing trees leaves homes and buildings exposed to the hot summer sun and frigid winter winds.
  
  

Soil Erosion

• Under the soil, a dense network of plant roots act as a net, holding soil and stabilizing areas where slope and water flow may result in soil erosion. After clearing an area of plants, rainwater and wind carry away soil particles. This nutrient-rich topsoil may take generations to rebuild. Furthermore, the soil particles carried by the water must end up somewhere and often fill lakes and streams with sediment, causing flooding, fish kills and destroying wildlife habitats. Eroded soil also contains toxins from synthetic fertilizers and pesticides that end up washed away with the eroded soil.
  
  

Collapsing Food Webs

• Plants are termed primary producers because they do not need to consume food in order to acquire energy; they manufacture energy from sunlight, carbon dioxide and water. This process makes energy from the sun available in a chemical form that other organisms can consume by eating plants. Plants, therefore, form the basis of the Earth's food web, and eliminating plants means fewer food sources available for people and animals.