Research Design

[popcornfrenzy]

I'm currently working on research proposals and I can't seem to wrap my head around the idea of what research design my topics falls to.

Topics:

• Identifying zooplankton biodiversity and its effect on the quality of local fisheries of grouper fish - I was told by my tutor that it is a quasi-experimental design but I don't get how it is since there is no manipulation of the variables since I'm just identifying the zooplankton present in the fisheries and looking if the groupers are affected in terms of their physical attributes, etc. I think it is more of a correlational study? Still, I need a clearer viewpoint on this.
• Analysis of the presence of heavy metals (specifically copper) in the local groundwater sources in a nearby abandoned copper mine- I also don't know if it is a experimental research since it also does not manipulate the variables and merely examining the properties of the groundwater sources. I also wanna know what data analysis suitable here? Like should it by like a significant difference thing? Like a comparison between the ideal/natural concentration vs the contaminated area? The more I look at it the more it resembles a controlled and treatment like experimental study.  However it still sort of natural or observational since I didn't manipulate the presence of heavy metals in the area and it didn't occur in a controlled environment like in a lab. I'm actually confused. 
• Identifying biodiversity - In general, is it experimental if I'm using dichotomous keys to identify species composition in a given ecosystem? If so, how do you do a statistical analysis for this? 

Thank you in advance for the responses 🙂

[CharonY]

2 hours ago, popcornfrenzy said:

Identifying zooplankton biodiversity and its effect on the quality of local fisheries of grouper fish - I was told by my tutor that it is a quasi-experimental design but I don't get how it is since there is no manipulation of the variables since I'm just identifying the zooplankton present in the fisheries and looking if the groupers are affected in terms of their physical attributes, etc. I think it is more of a correlational study? Still, I need a clearer viewpoint on this.

This to me does seem observational, rather than experimental. 

 

2 hours ago, popcornfrenzy said:

Analysis of the presence of heavy metals (specifically copper) in the local groundwater sources in a nearby abandoned copper mine- I also don't know if it is a experimental research since it also does not manipulate the variables and merely examining the properties of the groundwater sources. I also wanna know what data analysis suitable here? Like should it by like a significant difference thing? Like a comparison between the ideal/natural concentration vs the contaminated area? The more I look at it the more it resembles a controlled and treatment like experimental study.  However it still sort of natural or observational since I didn't manipulate the presence of heavy metals in the area and it didn't occur in a controlled environment like in a lab. I'm actually confused. 

This falls under monitoring or surveillance studies. However, you do need to start of with a question. In this case, you have implicitly stated that you suspect an impact of a (former) copper mine. What you then need to figure out what your control would be. For example, are there aquifers that you can trace up and down stream of the mine?

 

2 hours ago, popcornfrenzy said:

Identifying biodiversity - In general, is it experimental if I'm using dichotomous keys to identify species composition in a given ecosystem? If so, how do you do a statistical analysis for this? 

Measuring biodiversity is like measuring any other variable, it is not experimental as such (but can be made subject to manipulation). A very common way of quantifying biodiversity is using Simpson's Diversity Index.  But again, this is not a study in itself, just monitoring. A good research study would try to figure out the impact of something on biodiversity. And you would need to set up up your sampling method accordingly.

[popcornfrenzy]

8 hours ago, CharonY said:

This falls under monitoring or surveillance studies. However, you do need to start of with a question. In this case, you have implicitly stated that you suspect an impact of a (former) copper mine. What you then need to figure out what your control would be. For example, are there aquifers that you can trace up and down stream of the mine?

Hi CharonY, in a case that there are aquifers that I can trace up and down stream of the mine, how will I determine my control? Wouldn't the other aquifers be contaminated as well? These are just my assumptions. Also, to be clear, are monitoring/surveillance studies not experimental? Even if for example you isolate the heavy metals in the lab to examine their concentrations? If not, what are they classified to?

8 hours ago, CharonY said:

Measuring biodiversity is like measuring any other variable, it is not experimental as such (but can be made subject to manipulation). A very common way of quantifying biodiversity is using Simpson's Diversity Index.  But again, this is not a study in itself, just monitoring. A good research study would try to figure out the impact of something on biodiversity. And you would need to set up up your sampling method accordingly.

Oh, that clears the biodiversity aspect. But what if you're doing a taxonomic study as baseline for species composition in a given ecosystem or area? Like using only dichotomous keys. Because I've read some papers that did those kind of methodology and they still confuse me on what research design do they fall into or if they are even quantitative at all.

For example this paper: 

https://www.researchgate.net/publication/327654431_Freshwater_microcrustaceans_Cladocera_Anomopoda_and_Ctenopoda_Copepoda_Cyclopoida_and_Calanoida_in_the_highly_urbanized_Metropolitan_Manila_area_Luzon_Philippines

The study is about the microcrustaceans that were identified in Manila using different dichotomous keys. Are these kind of studies experimental? If not, in what design do they fall into?

Btw, thank you for clearing up the first topic

[CharonY]

4 hours ago, popcornfrenzy said:

Hi CharonY, in a case that there are aquifers that I can trace up and down stream of the mine, how will I determine my control? Wouldn't the other aquifers be contaminated as well?

You would need to understand the system a bit. I.e. if you hypothesize that the mine releases heavy metals, what is the expected zone of leeching and is there flow through the system? If so, you could select sampling points that targets water before it reaches that expected zone as well as downstream elements (where they should carry contaminants).

4 hours ago, popcornfrenzy said:

Also, to be clear, are monitoring/surveillance studies not experimental?

So this is a bit of a semantic issue and it depends on context. If you talk about the study design, you could for example distinguish monitoring projects (where you observe a system) and one where you manipulate it experimentally and then measure the outcome.

But you can also use the the term to determine whether something is wet lab (i.e. doing some sort of analyses) vs data crunching. 

4 hours ago, popcornfrenzy said:

Because I've read some papers that did those kind of methodology and they still confuse me on what research design do they fall into or if they are even quantitative at all.

Studies do not have to be quantitative, but even them the papers outline some sort of question. For example, the authors in the paper you linked outline that there is a knowledge gap regarding the crustaceans in urbanized areas;- the areas in question are interesting since there is data from the 50s but there has been increasing urbanization and pollution since then; and they also compared spatial distribution in between more and less-disturbed areas.

So again, a key point is the research question. The methodology follows from there (and generally not the other way round).

 

[popcornfrenzy]

Thanks for the answers, I'll look into these. I am just worried that if I ever formulate my research questions, I'll struggle a lot with finding the right methodology to use. It sort of bugs me that I do not know these things at the same time, thinking of having a carefully structured paper to pass my course subject. 

[CharonY]

The easiest way is to look at papers and emulate their study design for similar questions. You will build up an arsenal of methodologies for certain questions.