tailieunhanh - Heavy Metals in the Environment: Using Wetlands for Their Removal - Chapter 14

Cuốn sách này bao gồm các nghiên cứu khoa học chì và đất ngập nước được thực hiện trên các dự án Sendzimir DT, một cuộc điều tra chung của Trung tâm vùng đất ngập nước và chính sách môi trường của Đại học Florida, Gainesville và Đại học Mỏ và Luyện kim, Krakow, Ba Lan, năm 1990 đến 1998. • Hai vùng đất ngập nước với nồng độ cao dẫn từ nước thải đã được nghiên cứu, một ở Florida và một ở Ba Lan (cũng bao gồm kẽm). Các kết quả của những nghiên cứu cộng với làm việc với công bố dữ liệu. | CHAPTER 14 Summary Policy for Heavy Metals and Environment CONTENTS Suggested SUMMARY This book contains the scientific studies of lead and wetlands made on the . Sendzimir project a joint investigation by the Centers for Wetlands and Environmental Policy of the University of Florida Gainesville and the University of Mining and Metallurgy Krakow Poland 1990 to 1998. Two wetlands with high concentrations of lead from wastewaters were studied one in Florida and one in Poland which also included zinc . The results of these studies plus work with published data emerging elsewhere were used to generalize about lead in wetlands in society and the global biogeochemical cycle of lead. From evidences of many kinds we now realize that wetlands and their humic peat as they have evolved over geologic time are a gaia mechanism for making the biosphere safe for life and conversely evolving the kind of life that makes the geologic processes compatible. Because several kinds of processes were found binding lead in wetlands the lead not bound by one may be captured by another physical filtration of particles binding of soluble lead by negative surfaces of clays in sediment binding by humic organic matter and peat binding as insoluble sulfide crystals binding in wood substitution in shells and skeletons precipitation as oxides and carbonates etc. . Different processes are found in different degrees of prominence in different kinds of wetlands. Very little lead from rain and runoff gets past a wetland. Understanding of the distribution and movements of lead was found by developing simulation models of moderate complexity on the scale of time and space of whole wetlands. Important rates included were the inflows of lead movements of water percolation binding capacities growth of plants toxicity to plants sediment disturbance and organic matter respiration. The much faster rates of chemical reaction that are part of these larger-scale processes were not .