生态系统

• The world food imbalance is a problem of agricultural ecosystems and their management .
  世界粮食生产的不平衡是农业生态系统及其管理部门的一个问题。
• Regional ecosystem types, such as grass land, desert, and deciduous forest, are called biomes .
  地区的生态系统，例如草原、荒漠和落叶林又被称为生物带。
• The abundance and availability of water and nutrients in a soil ecosystem determine its fertility .
  土壤生态系统中水分和养分的丰度和有效性决定土壤的肥力。
• Continually warm, moist climates generally favor the development of complex and stable ecosystems .
  连续的温暖、湿润气候通常有利于发展复杂而稳定的生态系统。
• The species that make up natural ecosystems usually display a wide range of genetic variability .
  构成自然生态系统的生物种，通常表现有较大范围的遗传变异性。
• During this same period, other human activities will exert a variety of stresses on forest eco-systems .
  在同一时期内，其他人类活动将给森林生态系统带来种种胁迫。
• The plants of natural ecosystems are usually well adapted to the edaphic and climatic character of their region .
  自然生态系统的植物，通常十分适应当地的土壤和气候特点。
• How long can we continue to supplement agroecosystems with energy derived from declining fossil fuel supplies ?
  由于矿物燃料供应量下降，我们供应农业生态系统能量能持续多久？
• Aquatic ecosystems share a number of basic structural and functional characteristics with terrestrial ecosystems .
  水生生态系统的结构和机能，在许多基本特征方面同陆地生态系统一样。
• We tend to distinguish one ecosystem from another according to the most apparent features of its biological components .
  我们往往根据其中特征最明显的生物成分来区分不同的生态系统。