Reference no: EM132324362 , Length: word count:2000

Biogeochemistry & Trophic structures of urban pond ecosystems Assessment Task -

Practical objectives - The aim of this short practical course is to introduce you to the integrative analysis of composite data sets based on a number of techniques that are commonly used in studies of nutrient cycling and biogeochemistry (and therefore in ecosystem ecology). While our practical work is focused on only one or two particular aspects of nutrient (biogeochemical) cycling, these techniques and approaches are also applicable to many terrestrial (including agricultural), riparian, estuarine and marine systems. The idea is to get you thinking about the processes involved in maintaining the cycles of nutrients and organic matter, how particular processes are influenced by various abiotic and biotic factors, how you measure them and what these measurements can tell us about the functioning of a particular ecosystem, including its trophic structures.

In this project, we will focus primarily on characterising the distribution of C, N and P in different pond types around the XYZ campus. In this small project, we will investigate:

• indices of carbon, nitrogen and phosphorus availability (to plants, microbes and ultimately trophic structure) in relation to a range of environmental attributes of each pond;
• differences in the quality and origin of organic matter in and around the ponds that may impact on nutrient cycling processes;
• using isotopic signatures of different ecosystem components (plant, soils, invertebrates and other consumers) to trace the movement of carbon and nitrogen through an ecosystem).

We will undertake the sampling of water, soil/sediment, plant and whatever other samples you think are necessary to address the above as a group. Analyses of carbon, nitrogen and isotopes (including water isotopes) will be done for you but you will also be introduced to a common method of P analysis in Week 4, after the break.

The project will introduce you to the basics of stable isotope techniques, which are increasingly used in ecological, environmental and forensic studies (thus linked also with the lecture themes and your literature reviews). Coupled with the lecture course, this project will also introduce you to theory and techniques employed in the analysis of physical, hydrological, chemical, and ecological properties of ecosystems.

Project report & assessment -

You are expected to prepare a single well-structured scientific report in the style of a short journal article that integrates the data you will collect over the next couple in to a discussion of the influence of different vegetation types and environmental conditions on organic matter cycling at an urban wetland. You may, however, choose to focus on one or more key aspects of the study.

Assessment - Word limit 2000 words

Your final report should take the form of a short scientific paper in the format of a short paper in the journal Ecosystems (please follow the format of the journal EXACTLY, including fonts, presentation of figures and tables, formatting of references) with:

Abstract

Key words

Introduction

Materials and Methods (written as if you were preparing a journal article so you do not need to write out every step!) - The headings below are to get you started and to guide you with your organisation but you may use different sub-headings as you see fit - REMEMBER - you are trying to write a journal article.

Study site and experimental design

ADD EXTRA HEADINGS to summarise the other analyses you've undertaken, including data analysis

Results (including tables and figures) - What sub-headings might you use in your results section? Look at a scientific paper and see what sub-headings they use, how results are grouped and the way data are described.

Discussion

References Format you references as per the journal Ecosystems

Subsections and sub-headings are encouraged where appropriate. As a clue, try and think of your data in different ways. The following are just ideas - if you have some other bright ideas and searing questions then go ahead! Use the literature to stimulate your ideas. e.g.

1. Organic matter and microbial activity - Did the "quality" of the organic matter (C/N ratios of etc) vary among ponds or sample types (e.g. sediments/soils around the ponds versus plant material versus bird droppings)? Why might nutrient availability (P and N) have differed in the first place?

2. Phosphorus fractions -Is P availability related to organic matter content or concentration of other nutrients? Is most P in the inorganic or organic form?

3. Nutrient availability and internal/external cycling - are sediment, plant material and water column samples correlated? How did the nutrient contents and isotopic signatures compare among sample types? Did particular species show higher nutrient concentrations than others? If so, why do you think this might be the case?

4. What was the dominant form of N? Did isotopic signatures (δ15N, δ13C and δ18O) differ among ponds?

5. How is each "section" (above) related to the other? How can all of the above information be used to improve understanding and management of XYZ's ponds?

Presentation -

• Font must be 12 pt and 1.5 to double spaced lines (NOT single spacing)
• Try and limit yourself to a MAXIMUM of 5 Tables and/or Figures (i.e., think of imaginative ways of summarising your data) - pay attention to the presentation and follow a journal format. Don't repeat back to me something that I've already written out for you! These notes are a GUIDE, not a reference in themselves. Do NOT cite general textbooks, websites or un-refereed material unless you have a good reason for it. Use refereed journal articles.
• References should be presented using the journal format for Ecosystems.

There are abundant references contained within this set of notes and from your lectures but you should also conduct your own literature searches via electronic search engines, including the ISI Web of Knowledge (more likely to pick up recent publications) and Google Scholar.

Note - Biogeochemistry, 2000 words excluding references. It's a report should be written like a short journal article.

Attachment:- Assignment File.rar