Disruption of a Planetary Nitrogen Cycle as Evidence of Extraterrestrial Agriculture

Agriculture is one of the oldest forms technology on Earth. The cultivation plants requires a terrestrial planet with active hydrological and carbon cycles depends availability nitrogen in soil. technological innovation agriculture management this cycle by applying fertilizer to soil, at first through production manure excesses but later Haber-Bosch industrial process. use such fertilizers has increased atmospheric abundance nitrogen-containing species as NH$_3$ N$_2$O agricultural productivity intensifies many parts world. Both are effective greenhouse gases, combined presence these gases atmosphere habitable could serve remotely detectable spectral signature technology. Here we synthetic generator assess detectability that would arise from present-day future global-scale agriculture. We show Earth abundances be difficult detect hypothetical scenarios involving 30-100 billion people change transmittance about 50-70% compared pre-agricultural These calculations suggest possibility considering simultaneous detection an also contains H$_2$O, O$_2$, CO$_2$ technosignature for extraterrestrial sustainable across geologic timescales, so "ExoFarm" worth search technosignatures.