Dear ECOLOG member
*I urgently require your suggestions related to statistical approaches to
the following problem*
*The Problem*
I have been working on a coastal forest ecosystem and its sedimentary
biogeochemical processes. Recently due to cyclonic event, the area was
suddenly flash-flooded. The flood supposedly disturbed the sediment column
as well as retreating water deposited waste load .
*Approach*
Sediment cores (n=10) , collected from the area immediately after the
flood and sectioned at 5 cm interval for the geochemical analysis.
*Hypothesis*
*The flood has resulted in significant changes in the sediment column
biogeochemistry .*
The hypothesis is well supported by the experimental results . Geochemical
analysis of the cores at 5 cm interval indicates trends of deposition of
fresh sediments/disturbance/waste deposition
*Statistical approaches*
1. .Entire forest area cover is disturbed due to cyclonic flood i.e. the
spatial variation in the geochemical characteristics are not significant
2. The sediment columns has been disturb due to deposition I.e
variation in the geochemical characteristics along with depth are
significant .
*Help Needed*
* *
*Which test of significance will be more suitable. *
*I have applied ANOVA but have been getting conflicting response that *
* *
*" This is not totally appropriate for the samples collected especially in
sediment cores. Certain geochemical processes occur **down a sediment
column and there could be relations between samples. Therefore, the samples
(from different depth of a core) should not be treated as independent
samples and should not analyzed by using ANOVA ."*
Indeed, I have treated the different sections of a core along with depth as
individual independent samples and have compared with the correspond values
of other cores at any given depth.
*Now I am confused whether my approach is wrong or ANOVA can’t be applied
to the system ? What other statistical approached (apart from PCA) I can
do to check the significance of variation across depth*
* *
Any response in this regards will be highly appreciated . If you can
forward me the some of related research papers, I will be obliged .
Received response will be duely credited .
Regards
Dr. Gurmeet Singh
Jawaharlal Nehru University
New Delhi
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