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Late-Medieval Horse Remains at Cesis Castle, Latvia, and the Teutonic Order's Equestrian Resources in Livonia
EXCAVATIONS AT the castle complex of Cēsis, Latvia, uncovered an unusual find of large quantities of horse bones, some of which were partially articulated, along with equestrian equipment. These were associated with a destroyed building at the edge of the southern outer bailey. The horses included large males, most probably stallions, and pathology on several of the recovered vertebrae suggests these individuals had been used for riding. The size of the horses was within the range for medieval war horses, and the associated tack also pointed to prestigious riding animals. Radiocarbon dating of the bones placed them firmly within the Teutonic Order's period of rule. We conclude here that these horses fulfilled a military role in the final decades of the Teutonic Order’s rule in Livonia in the late 15th/early 16th century and that the better-known equestrian culture of late-medieval Prussia was comparable in character, if not in scale, to that in Livonia
Biparental inbreeding depression, genetic relatedness and progeny vigour in a wind-pollinated treeline species in Argentina
Different pathways of formation of N2O, N-2 and NO in black earth soil
The use of N-15 tracer provides a suitable technique to investigate the processes of N transformation in soils and the origin of the environmentally relevant gaseous N compounds N2O and NO from nitrification and denitrification. incubation experiments with black earth soil under two different water contents are presented here. Nitrification and denitrification proceeded simultaneously, but the importance of these two microbial processes shifted depending on the water content of the soil. Under water-unsaturated conditions the microbial oxidation of NH4+ to NO3- predominated, but a reduction of NO3- also occurred. The emission of NO exceeded the emission of N2O by a factor of up to 20 at the beginning of the experiments. Under water-saturated conditions denitrification was the dominant process of N transformation in the soil. However, nitrification also occurred to a considerable extent. The emission of N2O was greater than under unsaturated conditions. The formation of NO could hardly be observed. N loss by molecular nitrogen from denitrification could be detected under saturated conditions. The N loss amounted to 60% of NO3- and thereby the cumulative N ratio of N-2 to N2O was 3. Under either unsaturated or saturated conditions NO arose from NO2- or during the microbial oxidation of NH4+ to NO2-. However, N2O mainly formed from denitrification under both conditions. Furthermore, NO could not be observed as a precursor of N2O and the free NO2- could not be detected as a common N pool for the formation of N2O and NO. High emissions of NO could be a problem for the black earth soil in the semi-arid climate in central Germany, if there are large amounts of NH4+ in the soil after fertilisation. (C) 2000 Elsevier Science Ltd. All rights reserved
Einfluss von Rohrglanzgras (Phalaris Arundinacea L.) auf N-Umsetzungsprozesse und die Emission Klimarelevanter Spurengase in Modellversuchen mit Niedermoorsubstrat
Nitrous oxide and dinitrogen losses from flooded fen peat with and without reed canarygrass (Phalaris arundinacea L.) and common reed (Phragmites australis (Cav.) Trin. ex Steud.) plants
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