Databases can help you to search for relevant resources. There are two main kinds of database you're likely to come across:
Bibliographic databases index the titles and abstracts of journal articles, books and conference papers. They are useful for conducting a structured literature search across a large range of publications. You can check which publications are included in the search. Though the databases themselves usually don't include the full text, most databases are linked to Oxford holdings so you can easily find out how to access any articles you are interested in. Look for the 'Find it @ Oxford' link.
Full-text databases allow you to access and search the full text of literary and critical works. You could, for example, search for every use of a particular word within the works of a given author.
If you'd like to find out which databases are available, you can browse by subject in Databases A-Z. Relevant subject headings include Geography and the Environment, Plant Sciences and Biological Sciences.
Here are some key full-text databases for students of Environmental Conservation.
To find more, go to Databases A-Z click the Subject tab and scroll down to select Geography and the Environment.