tailieunhanh - Handbook of Water and Wastewater Treatment Plant Operations - Chapter 12

Các vấn đề được phát hiện chứng minh thậm chí còn khó hơn so với những người chúng ta đã gặp phải. Trong khôi phục lại hoạt động của chúng tôi và đứng nước trạng thái nguyên sơ ban đầu của họ, điều này đã được tìm thấy là trường hợp. Những người bị ảnh hưởng bởi khoa học của hệ sinh thái nước ngọt (ví dụ như, các học viên nước) phải hiểu được tác động của môi trường căng thẳng, chẳng hạn như chất độc, các hệ sinh thái vi sinh vật trong việc điều hành và đứng. | 12 Water Ecology Streams are arteries of earth beginning in capillary creeks brooks and rivulets. No matter the source they move in only one direction downhill the heavy hand of gravity tugs and drags the stream toward the sea. During its inexorable flow downward now and then there is an abrupt change in geology. Boulders are mowed down by slumping gravity from their in place points high up on canyon walls. As stream flow grinds chisels and sculpts the landscape the effort is increased by momentum augmented by turbulence provided by rapids cataracts and waterfalls. These falling waters always hypnotize us like fire gazing or wave-watching Before emptying into the sea streams often pause forming lakes. When one stares into a healthy lake its phantom blue-green eye stares right back. Only for a moment relatively speaking of course because all lakes are ephemeral doomed. Eventually the phantom blue-green eye is close lidded by the moist verdant green of landfill. For water that escapes the temporary bounds of a lake most of it evaporates or moves on to the sea. INTRODUCTION This chapter deals primarily with the interrelationship the ecology of biota life forms in a placid water body lake and running water stream environment. The bias of this chapter is dictated by our experience and interest and by our belief that there is a need for water and wastewater operators to have a basic knowledge of water-related ecological processes. Ecology is important because the environmental challenges we face today include all the same ones that we faced more than 30 years ago at the first Earth Day celebration in 1970. In spite of unflagging efforts of environmental professionals and others environmental problems remain. Many large metropolitan areas continue to be plagued by smog our beaches are periodically polluted by oil spills and many of our running and standing waters streams and lakes still suffer the effects of poorly treated sewage and industrial discharges. However .