The application of flue gas desulfurization (FGD) gypsum to ameliorate saline-alkaline soils not only provides a new use for FGD gypsum, but also provides a new method for improving saline-alkaline soils. This paper reviews the development of this technology for ameliorating saline-alkaline soils over the past 20 years including the basic theory, key technologies, short and long-term effects, environmental safety and industrialized applications of treating saline-alkaline soils with FGD gypsum. This paper also presents the future research needs to address current problems for large-scale applications. Efficient and safe treatments of large saline-alkaline soil areas using FGD gypsum should reduce the application rate of FGD gypsum per unit land area, increase long-term positioning of test points and formulate national standards for agricultural application of FGD gypsum.

Project boundary setting and leakage treatment are two important issues to be considered when a clean development mechanism (CDM) project is being designed. There are still many uncertainties concerning these two issues. This paper reviews the concepts of project boundary setting and leakage in CDM projects, cites the types and sources of leakage, discusses the principles for determining leakage, and gives some proposed methods for dealing with leakage. A case study, using several steps to solve the boundary and leakage problems, shows how the analyzed principles and treatments can be implemented in a real project. Based on the result of the case study, the methods discussed are shown to be appropriate for settling leakage issues.