I study soil insects, and sample monthly for insects. Each month, I sample at 8 different sites. Each site is divided roughly into 4 meter square quadrants (shown in figure). From each quadrant, I pick out ~ 50 cm^2 of soil and look for insect samples (solid filled circles). I repeat this each month.
I do not have GPS points for each of the colored circle but I know that it belongs to different quadrant. Each ~ 50 cm^2 of soil is unique spatially and temporally.
Data-wise I have a grid that looks like this for each month.
site1.Q1 site1.Q2 site1.Q3 site1.Q4 site2.Q1 site2.Q2 ... species 1 0 5 10 2 40 5 species 2 90 0 0 0 22 1 species 3 7 0 0 2 89 90
I want to analyze: (a) Is there spatial aggregation within a site for each species? (b) What is the extent of spatial niche overlap between species? How does this change over time?
For (a) Would Lolyd's Mean Crowding Index is a good estimator of aggregation here? What other indices, or tests would be recommended?
For (b) If species species aggregate, then species may overlap in few of the 50 cm^2 soil samples. How can I test the extent of overlap? Some examples suggest Schoener's D but I'm not sure if that needs some abiotic variable like temperature/ moisture measurement.