北师大版高中英语选修八unit22environmentalprotectiontheeleventhperiod教案

北师大版高中英语选修八unit22environmentalprotectiontheeleventhperiod教案内容摘要：

islands). Temperate rainforests are found along the Pacific coast of the USA and Canada (from northern California to Alaska), in New Zealand, Tasmania, Chile, Ireland, Scotland and Norway. They are less abundant than tropical rainforests. Rainfall It is almost always raining in a rainforest. Rainforests get over 80 inches (2 m) of rain each year. This is about 1 1/2 inches ( cm) of rain each week. The rain is more evenly distributed throughout the year in a tropical rainforest (even though there is a little seasonality). In a temperate rainforest, there are wet and dry seasons. During the dry season, coastal fog supplies abundant moisture to the forest. Temperature The temperature in a rainforest never freezes and never gets very hot. The range of temperature in a tropical rainforest is usually between 75176。 F and 80176。 F (24 27176。 C). Temperate rainforests rarely freeze or get over 80176。 F (27176。 C). The Soil in a Rainforest The soil of a tropical rainforest is only about 34 inches ( cm) thick and is ancient. Thick clay lies underneath the soil. Once damaged, the soil of a tropical rainforest takes many years to recover. Temperate rainforests have soil that is richer in nutrients, relatively young and less prone to damage. The Importance of Rainforests Tropical rainforests cover about 7% of the Earth39。 s surface and are VERY important to the Earth39。 s ecosystem. The rainforests recycl。