Finals task and exercises

1 Lecture

2 Exercises

2.1 Exercise 1: Plant species richness in fragmented landscapes

2.1.1 Question

How do the area and isolation of island-like habitat fragments influence plant species diversity?

2.1.2 Background

In 33 island-like fragments with semi-natural grassland vegetation the number of plant species was recorded. In addition, the area and the isolation of each fragments was measured from satellite images. The isolation is measured as the distance to the nearest neighbour fragment.

2.1.3 Dataset

File: 09_dataset1_spec_frag.csv

Variables

area_ha: Area of the fragment in hectare
nn_dist_m: Isolation measured as distance to the nearest neighbor fragment in meters
species_richness: No. of plant species

2.1.4 Solution

Solutions

2.2 Exercise 2: Browsing damage on tree saplings

2.2.1 Question

How does browsing intensity vary among tree species and with canopy coverage?

2.2.2 Background

In 60 plots in German forest the total number of tree saplings and the number of saplings damaged by (roe)-deer browsing of three species were sampled. In addition, the canopy closure at the plot was measured as proxy for light availability.

2.2.3 Dataset

File: 09_dataset2_tree_browsing.csv

Variables

canopy_closure: measured in %
species: tree species
N_browsed: No. of damaged saplings
N_total: Total no. of saplings

2.2.4 Solution

Solutions