Topic

Choose one of the following topics:

1. Soils differ in their capability and suitability for various uses. Describe the scientific basisand application of one or more schemes (international, national or state)that definesoil capability.

2. Choose an essential element (for plants) and describe the factors determining it's availability to plant roots in soil.

3. Soils differ in their ‘suppressiveness' to soil-borne diseases of plants. What are the mechanisms determining suppressiveness to one or more important soil-borne diseases?

4. Choose an important soil degradation process and describe the mechanisms by which it occurs.

Essay length

Maximum of 2,000words (excluding abstract, tables and references).

Researching your essay

A good essay will rely on a range of scientific papers and/or books. The information in scientific papers and books is reliable because, before they can be published, they are reviewed (or ‘refereed') by independent scientists. If conclusions are not justified by the evidence, publication is refused. There are many good soil-related books in the library on both campuses, mostly around 631.4, and many good on-line scientific journals available through the library and searchable with library databases.

I suggest that your start researching your essay by finding review-type articles that cover the field of interest. You can start with the textbook! Youcanthen search deeper using the references cited in the review(s). The other main approach is to search the JCU library using One Search. You can of course use Google (or Google Scholar) too, but beware, because you may get an enormous number of hits and the ones near the top of the list (the ones you're most likely to look at) are not necessarily the most appropriate.

Have a look at the libguides for earth sciences (http://libguides.jcu.edu.au/earth) and environmental sciences (http://libguides.jcu.edu.au/environment) for appropriate databases. The library databases can be used to gain free full text access to subscribed resources

Some general points about the types of information you can draw upon to write an essay. (see http://libguides.jcu.edu.au/evaluating for more information)

1. Some scientific publications are in the form of reviews. These appear as papers in scientific journals, as book chapters, as books, and as reports for various organizations. They are increasingly published online, but many good recent ones are not necessarily online. They usually attempt to cover all of the most important literature relevant to the topic. They may be aligned with the author's interests and expertise or the sponsoring organisation's needs, but they usually provide good coverage of a topic. Their broad coverage allows you to pursue particular topics using their reference list. It may be hard to assess the quality of un-refereed reports as they have not necessarily been through a scientific peer review process, and whether they have or have not is often unclear (unlike scientific journal articles, which have all been peer-reviewed). To assess reliability, see if the report has been written by a recognised expert in the field and if it's published by a recognised authority or organisation. Reviews are a good source of information for the essay topics given.

2. Most of the useful information on topics such as these originates from research in the field or laboratory, which is reported in scientific papers. They give clear evidence on specific questions. However, when writing an essay on a topic such as those given, the sheer volume of research on the given topics means that it would be impossible to read all the relevant papers. Be aware of this, and try to cover a range of papers rather than focussing on one or two.

3. You can of course find lots of information relevant to these topics in all sorts of non-refereed articles, online or other. They may be aimed at giving a general overview of a subject, often to people with little or no training in the field. They are extremely variable in quality. Read critically, as many myths, misconceptions and statements based on no evidence are promulgated. If no author is acknowledged, be even more wary. References to this kind of information does not carry much weight or may even detract from your essay.