%0 Conference Paper
%A Elbe, Ulrike
%A Roß, Antje
%A Steffens, Günter
%A Van den Weghe, Herman
%A Winckler, Christoph
%D 2005
%E Heß, J
%E Rahmann, G
%F orgprints:3842
%I kassel university press GmbH, Kassel
%K Geflügel, Nährstoffmanagement, Freiland
%T Ökologische Legehennenhaltung in großen Herden: Spezifische Auslaufnutzung und Nährstoffeintrag
%U http://orgprints.org/3842/
%X The aim of this study was to examine the excrement load in outdoor ranges due to the outdoor run use of free-range laying hens (organic farming system) to quantify the accumulation of nutrients in the soil. The number of hens using the run (flock of 4,500 hens) were recorded (digital photographs; scan sampling interval 10 min, 5 hours/d, 23 d; 7 to 10/2003) and sward protection grids, positioned at different distances (2 , 6, 17 m) from the barn were used to get the amount of excreta (number and weight of droppings).  On average 9.8 % of the hens used the range out of which 69 % preferred the area close to the barn (0-17 m). Excretion rates per hen amounted to 12,4 g*hour, thus accounting for a share of 5 % of the total excrements of the flock. The calculated amount of nitrogen in the soil reached a very high level in the area close to the barn, but with regard to the entire outdoor area only usual fertilisation level. Preventive measures to protect the soil close to the barn are recommended.