The Effects of Manure Application and Herbivore Excreta on Plant and Soil Properties of Temperate Grasslands—A Review

This review provides an overview of grassland studies on the effects of manure application and herbivore excreta on plant and soil properties in temperate grasslands. Grass biomass from grazing or mowing is mainly used for animal products such as milk or meat, as well as for energy or raw materials for biorefineries. Manure application or grazing has a significant impact on several plant and soil properties. There are effects on soil chemical properties, such as increased carbon sequestration, improved nutrient availability, and increased pH. Additionally, several physical soil properties are improved by manure application or grazing. For example, bulk density is reduced, and porosity and hydraulic conductivity are greatly improved. Some biological parameters, particularly microbial biomass and microbial and enzyme activity, also increase. The use of manure and grazing can, therefore, contribute to improving soil fertility, replacing mineral fertilizers, and closing nutrient cycles. On the other hand, over-application of manure and overgrazing can result in a surplus of nutrients over plant needs and increase losses through emission or leaching. The lost nutrients are not only economically lost from the nutrient cycle of the farm but can also cause environmental damage.