Results

Spatial density distribution of cattle

Cattle prefered certain areas on pastures presumingly based on different environmental factor and vegetation characteristics. No significant differences could be found regarding habitat preference between the spatial density distribution of the behaviour groups resting and grazing.

Spatial density distribution maps of grazing (a) and resting (b) cattle.

Environmental impact on the spatial distribution of grazing cattle

In the singular models for both behaviours all environmental factors were siginificantly influencing the habitat preferences of the cattle. Analysed for the grazing cattle in one modell, the grazing cattle showed similar responses to the environmental factors like in the singular models.

Visualisation of all the effect of the environmental factors on grazing cattle spatial density distribution; all analysed in the same model

Grazing cattle showed a clearly negative linear response to tree and shrub cover which were highly significant, while species richness showed a strong positive linear response in cattle density of the high significance. The non-linear response to vegetation height and was also significant and shows preference for medium low vegetation height. Grazing cattle showed a weaker positive linear response to indicator species diversity, with more variation at the higher value end, however, this observation was not significant. Furthermore, cattle showed an overall negative non-linear response to soil moisture, that was not significant. Terrain ruggedness showed a highly significant negative linear response of grazing cattle with a high amount of variation at the higher end.

Changes in spatial density distribution due to weather factors

Changes in habitat preference (canopy cover and soil moisture) due to weather factors were non-significant for grazing cattle. For the resting cattle however, the changes in preference for canopy increased and the preference for soil mositure decreased significantly with increasing temperature and percipitation level. Resting cattle prefered areas of high shrub cover with higher precipitation levels and areas of higher tree cover with higher hourly temperature.

Ecological implications

The vegetation height decreased in value and variation during the study period. The average vegetation decreased from around 5 in the grazing season to around 3 in the after season. The vegetation height in the afterseason varied between 3 and 4.

Boxplot digramm showing the variation in vegetation height during the study season.

In total 198 plant species were found, which 11 were classed as indicator species. The highest species rich areas matched areas of high and medium grazing intensity as well as open areas of medium vegetation height and medium soil mositure.

Nutrient transfers

A correlation test showed that the areas of high cow dung density are significant differently to the areas that show a high density for grazing events.

Maps showing the difference in porportion per grid of grazing event and cow dung.

The map shows that there are areas of higher grazing density than cow dung (dark purple), indicating areas of nutrient depletion, and areas of higher cow dung density (yellow), indicating areas of nutrient accumulation, within both pastures. The test for a relationship between species richness and nutrients showed a significant negative response of species richness to higher differences (cow dung porportion bigger than porportion of grazing density). The indicator species richness showed a similar responser, it was however, not significant.