holland.arthropods {agridat} | R Documentation

## Counts of arthropods in a grid-sampled wheat field

### Description

Counts of arthropods in a grid-sampled wheat field

### Usage

    data("holland.arthropods")

### Format

A data frame with 63 observations on the following 8 variables.

`row`

  row

`col`

  column

`n.brevicollis`

  species counts

`linyphiidae`

  species counts

`collembola`

  species counts

`carabidae`

  species counts

`lycosidae`

  species counts

`weedcover`

  percent weed cover

### Details

Arthropods were sampled at 30m x 30m grid in a wheat field near Wimborne, Dorest, UK on 6 dates in Jun/Jul 1996. Arthropod counts were aggregated across the 6 dates.

Holland et al. used SADIE (Spatial Analysis by Distance Indices) to look for spatial patterns. Significant patterns were found for N. brevicollis, Carabidae, Lycosidae. The Lycosidae counts were also significantly associated with weed cover.

### Source

Holland J. M., Perry J. N., Winder, L. (1999). The within-field spatial and temporal distribution of arthropods within winter wheat. Bulletin of Entomological Research, 89: 499-513. Figure 3 (large grid in 1996). http://doi.org/10.1017/S0007485399000656

Used with permission of John Holland.

### Examples

    data(holland.arthropods)
    dat <- holland.arthropods

    # use log count to make it possible to have same scale for insects
    if(require(reshape2) & require(lattice)){
      grays <- colorRampPalette(c("#d9d9d9","#252525"))
      dat2 <- melt(dat, id.var=c('row','col'))
      contourplot(log(value) ~ col*row|variable, dat2,
                  col.regions=grays(7), region=TRUE,
                  main="holland.arthropods - log counts in winter wheat")
    }

    ## Not run:
      # individual species
      require(lattice)
      grays <- colorRampPalette(c("#d9d9d9","#252525"))
      contourplot(linyphiidae ~ col*row, dat, at=c(0,40,80,120,160,200), region=TRUE,
                  col.regions=grays(5),
                  main="holland.arthropods - linyphiidae counts in winter wheat")
      contourplot(n.brevicollis ~ col*row, dat, region=TRUE)
      contourplot(linyphiidae~ col*row, dat, region=TRUE)
      contourplot(collembola ~ col*row, dat, region=TRUE)
      contourplot(carabidae ~ col*row, dat, region=TRUE)
      contourplot(lycosidae ~ col*row, dat, region=TRUE)
      contourplot(weedcover ~ col*row, dat, region=TRUE)

    ## End(Not run)

[Package agridat version 1.16 Index]