Introduction

Abstract

Abstract This chapter introduces the field of microbial ecology and some terms used in the rest of the book. Microbial ecology, which is the study of microbes in natural environments, is important for several reasons. Although most are beneficial, some microbes cause diseases of higher plants and animals in aquatic environments and on land. Microbes are also important because they are directly or indirectly responsible for the food we eat. They degrade pesticides and other pollutants contaminating natural environments. Finally, microbes are important in another ‘pollution’ problem: the increase in greenhouse gases such as carbon dioxide and methane in the atmosphere. Because microbes are crucial for many biogeochemical processes, the field of microbial ecology is crucial for understanding the effect of greenhouse gases on the biosphere and for predicting the impact of climate change on aquatic and terrestrial ecosystems. Even if the problem of climate change was solved, microbes would be fascinating to study because of the weird and wonderful things they do. The chapter ends by pointing out the difficulties in isolating and cultivating microbes in the lab. In many environments, 〈 1 per cent of all bacteria and probably other microbes can be grown in the lab. The cultivation problem has many ramifications for identifying especially viruses, bacteria, and archaea in natural environments and for connecting up taxonomic information with biogeochemical processes.