Essays about: "Johan Penner"

Found 2 essays containing the words Johan Penner.

1. 1. Effect of temporal increases in prey fish abundance on individual growth rates of coastal piscivores

   University essay from Umeå universitet/Institutionen för ekologi, miljö och geovetenskap

   Author : Johan Penner; [2016]
   Keywords : Three-spined stickleback; Perch; Growth; Intraguild Predation; Ontogeny; Baltic Sea.;

   Abstract : Commercial fishing in the Baltic Sea has led to decrease in abundance of large predatory fish and as a result the predation pressure on smaller fish species has been reduced. Three-spined stickleback (Gasterosteus aculeatus) is among the species that have benefited from reduced predation pressure. READ MORE

3. 2. Foliar nutrition: targeted fertilization to test herbivore preference

   University essay from Umeå universitet/Institutionen för ekologi, miljö och geovetenskap

   Author : Johan Penner; [2014]
   Keywords : Foliar nutrition; Salix viminalis; Phratora vulgatissima; Fertilization; Feeding trial;

   Abstract : Abstract   The aim of this study was to increase knowledge of how plants as a whole respond to targeted fertilization and to refine the method of foliar nutrition fertilization. The experiment also aimed to test how herbivores respond when presented with a choice between fertilized and unfertilized Salix leaves in a feeding trial experiment. READ MORE