tailieunhanh - Humic Matter in Soil and the Environment: Principles and Controversies - Chapter 9 (END)

MÔI TRƯỜNG VÀ CÔNG NGHIỆP TẦM QUAN TRỌNG CỦA VẤN ĐỀ Humic TẦM QUAN TRỌNG TRONG MÔI TRƯỜNG Bởi vì duy nhất hành vi trao đổi điện và ion của nó, vấn đề humic đóng một vai trò quan trọng trong môi trường. Chức năng của nó trong đất và các chu kỳ sinh hóa là rất quan trọng mà nhiều người, nếu không phải tất cả, các hoạt động sinh hóa sẽ đi đến bế tắc trong sự vắng mặt của vật chất humic. Sự xuống cấp của đất bắt đầu với sự phá hủy của vật chất humic, mang. | CHAPTER 9 ENVIRONMENTAL AND INDUSTRIAL IMPORTANCE OF HUMIC MATTER IMPORTANCE IN THE ENVIRONMENT Because of its unique electrochemical and ion exchange behavior humic matter plays a significant role in the environment. Its function in soils and the biochemical cycles is so vital that many if not all biochemical activities will come to a standstill in the absence of humic matter. Degradation of soils starts with the destruction of humic matter bringing with it all kinds of environmental disasters. In preceding chapters humic matter has been discussed as a participant in the carbon and nitrogen cycles two important cycles for maintaining a healthy environment in the soil s ecosystem. Fixation of organic carbon and proteinaceous compounds in the form of humic matter functions as part of the cycles enriching soils with much needed organic matter and nitrogen for survival of soil organisms. By later decomposition of humic matter the fixed carbon and nitrogen are released again enabling continuation of the respective cycles. Without the synthesis of humic matter most of the carbon will be lost rapidly Copyright n 2003 by Marcel Dekker Inc. All Rights Reserved. in the atmosphere in the form of CO2 gas leaving the soil void of organic matter. The ensuing disastrous effects of soil degradation can be prevented through management practices aimed at accumulation and maintenance of sufficient amounts of organic matter in soils. For more details reference is made to Tan 2000 . Preservation of Soil Organic Matter In preceding chapters it has been pointed out that soil organic matter is perhaps the most important soil component that has attracted a lot of attention since the early days of agriculture. Regardless of opinions to the contrary it is difficult to dispute the fact that the growth and yield of crops are always better in soils rich in organic matter. This is the reason why soils rich in organic matter such as the mollisols can support huge production of corn .