David Janke

Dr. David Janke

Leibniz Institute for Agricultural Engineering and Bioeconomy, Potsdam, Brandenburg, Germany
orcid

Research Focus & Metrics

Academic Career Length

10Years (2017-Present)

(Calculated once Scilit publication data is synced: current year − year of first publication + 1)

Representative Publications

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5 December 2019 in Earth System Dynamics
Verified
Journal Article
Open access
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Sabrina HempelSabrina Hempel
Sabrina Hempel
CMChristoph Menz
Christoph Menz
SPSeverino Pinto
Severino Pinto
EGElena Galán
Elena Galán
David JankeDavid Janke
David Janke
Thomas AmonThomas Amon
Thomas Amon
In the last decades, a global warming trend was observed. Along with the temperature increase, modifications in the humidity and wind regime amplify the regional and local impacts on livestock husbandry. Direct impacts include the occurrence of climatic stress conditions. In Europe, cows are economically highly relevant and are mainly kept in naturally ventilated buildings that are most susceptible to climate change. The high-yielding cows are particularly vulnerable to heat stress. Modifications in housing management are the main measures taken to improve the ability of livestock to cope with these conditions. Measures are typically taken in direct reaction to uncomfortable conditions instead of in anticipation of a long-term risk for climatic stress. Measures that balance welfare, environmental and economic issues are barely investigated in the context of climate change and are thus almost not available for commercial farms. Quantitative analysis of the climate change impacts on animal welfare and linked economic and environmental factors is rare. Therefore, we used a numerical modeling approach to estimate the future heat stress risk in such dairy cattle husbandry systems. The indoor climate was monitored inside three reference barns in central Europe and the Mediterranean regions. An artificial neuronal network (ANN) was trained to relate the outdoor weather conditions provided by official meteorological weather stations to the measured indoor microclimate. Subsequently, this ANN model was driven by an ensemble of regional climate model projections with three different greenhouse gas concentration scenarios. For the evaluation of the heat stress risk, we considered the number and duration of heat stress events. Based on the changes in the heat stress events, various economic and environmental impacts were estimated. The impacts of the projected increase in heat stress risk varied among the barns due to different locations and designs as well as the anticipated climate change (considering different climate models and future greenhouse gas concentrations). There was an overall increasing trend in number and duration of heat stress events. At the end of the century, the number of annual stress events can be expected to increase by up to 2000, while the average duration of the events increases by up to 22 h compared to the end of the last century. This implies strong impacts on economics, environment and animal welfare and an urgent need for mid-term adaptation strategies. We anticipated that up to one-tenth of all hours of a year, correspondingly one-third of all days, will be classified as critical heat stress conditions. Due to heat stress, milk yield may decrease by about 2.8 % relative to the present European milk yield, and farmers may expect financial losses in the summer season of about 5.4 % of their monthly income. In addition, an increasing demand for emission reduction measures must be expected, as an emission increase of about 16 Gg of ammonia and 0.1 Gg of methane per year can be expected under the anticipated heat stress conditions. The cattle respiration rate increases by up to 60 %, and the standing time may be prolonged by 1 h. This causes health issues and increases the probability of medical treatments. The various impacts imply feedback loops in the climate system which are presently underexplored. Hence, future in-depth studies on the different impacts and adaptation options at different stress levels are highly recommended.

1 October 2020 in Biosystems Engineering
Verified
Journal Article
Open access
David JankeDavid Janke
David Janke
DWDylia Willink
Dylia Willink
CAChristian Ammon
Christian Ammon
SHSabrina Hempel
Sabrina Hempel
SSSabine Schrade
Sabine Schrade
Thomas AmonThomas Amon
Thomas Amon

1 April 2018 in Energy and Buildings
Verified
Journal Article
Closed access
Qianying YiQianying Yi
Qianying Yi
GZGuoqiang Zhang
Guoqiang Zhang
MKMarcel König
Marcel König
David JankeDavid Janke
David Janke
Sabrina HempelSabrina Hempel
Sabrina Hempel
Thomas AmonThomas Amon
Thomas Amon

1 February 2018 in Biosystems Engineering
Verified
Journal Article
Open access
Sabrina HempelSabrina Hempel
Sabrina Hempel
MKMarcel König
Marcel König
CMChristoph Menz
Christoph Menz
David JankeDavid Janke
David Janke
BABarbara Amon
Barbara Amon
Thomas AmonThomas Amon
Thomas Amon

1 February 2021 in Computers and Electronics in Agriculture
Verified
Journal Article
Open access
EDE. Moustapha Doumbia
E. Moustapha Doumbia
David JankeDavid Janke
David Janke
QYQianying Yi
Qianying Yi
TAThomas Amon
Thomas Amon
MKMartin Kriegel
Martin Kriegel
SHSabrina Hempel
Sabrina Hempel

1 July 2019 in Computers and Electronics in Agriculture
Verified
Journal Article
Closed access
Qianying YiQianying Yi
Qianying Yi
Xiaoshuai WangXiaoshuai Wang
Xiaoshuai Wang
GZGuoqiang Zhang
Guoqiang Zhang
HLHao Li
Hao Li
David JankeDavid Janke
David Janke
Thomas AmonThomas Amon
Thomas Amon