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Enzymes in the Environment: Activity, Ecology and Applications - Chapter 16

Một dự án của Chương trình Môi trường Liên Hợp Quốc về đánh giá toàn cầu suy thoái đất đã kết luận, "Gần 40% của tất cả các vùng đất nông nghiệp đã bị ảnh hưởng bất lợi do sự thoái hóa đất do con người gây ra, và trên 6% sẽ đòi hỏi đầu tư vốn lớn để khôi phục lại năng suất ban đầu của nó "(1). Đó là, do đó, không ngạc nhiên rằng, trong số các cơ quan quản lý, có một mong muốn mạnh mẽ cho sự phát triển của các chỉ số nhạy cảm. | 16 Hydrolytic Enzyme Activities to Assess Soil Degradation and Recovery Tom W. Speir Institute of Environmental Science and Research Porirua New Zealand Des J. Ross Landcare Research Palmerston North New Zealand I. INTRODUCTION A project of the United Nations Environmental Program on Global Assessment of Soil Degradation concluded Nearly 40 of all agricultural land has been adversely affected by human-induced soil degradation and over 6 would require major capital investment to restore its original productivity 1 . It is therefore not surprising that among regulatory authorities there is a strong desire for the development of sensitive indicators to assess soil degradation. Properties that provide a snapshot assessment of the status of a soil can determine whether a management practice has had an adverse effect on soil health and productivity and better still can predict whether a practice will have an adverse effect if it is continued. This has been one of the major drivers of the worldwide research effort on soil quality defined as the capacity of a soil to function within ecosystem and land-use boundaries to sustain biological productivity maintain environmental quality and promote plant and animal health 1 . This topic has been the subject of numerous reviews such as those found in the Soil Science Society of America Special Publications 35 2 and 49 3 . We do not wish to enter the debate concerning a potential role for enzyme activity measurements in the wide soil-quality context this topic has already been reviewed 4-6 but to focus on the application of soil enzymes to scenarios in which soil degradation is demonstrable or at least strongly suspected to be a likely outcome of a particular land-management practice. In this review we do not present the many sometimes contradictory reports of effects of different management practices on soil enzyme activities that have already been reviewed in detail 6-14 but rather use our knowledge and perceptions of soil .