Do compost-based landfill biocover systems designed for methane oxidation emit nitrous oxide in significant amounts?

Landfills constitute a significant source of methane (CH), thereby contributing to climate change. CH emissions from old and smaller landfills can be mitigated by compost-based biocover systems designed for optimal microbial CH oxidation. It is well-known that the strong greenhouse gas nitrous oxide (NO) is generated during the composting process, which potentially could continue after incorporating compost into the biocover system.

Ancient DNA reveals admixture history and endogamy in the prehistoric Aegean.

The Neolithic and Bronze Ages were highly transformative periods for the genetic history of Europe but for the Aegean-a region fundamental to Europe's prehistory-the biological dimensions of cultural transitions have been elucidated only to a limited extent so far. We have analysed newly generated genome-wide data from 102 ancient individuals from Crete, the Greek mainland and the Aegean Islands, spanning from the Neolithic to the Iron Age. We found that the early farmers from Crete shared the same ancestry as other contemporaneous Neolithic Aegeans.

Effect of different ammonia sources on aceticlastic and hydrogenotrophic methanogens.

Ammonium chloride (NHCl) was usually used as a model ammonia source to simulate ammonia inhibition during anaerobic digestion (AD) of nitrogen-rich feedstocks. However, ammonia in AD originates mainly from degradation of proteins, urea and nucleic acids, which is distinct from NHCl. Thus, in this study, the inhibitory effect of a "natural" ammonia source (urea) and NHCl, on four pure methanogenic strains (aceticlastic: Methanosarcina thermophila, Methanosarcina barkeri; hydrogenotrophic: Methanoculleus bourgensis, Methanoculleus thermophilus), was assessed under mesophilic (37 °C) and thermophilic (55 °C) conditions.

Effect of organic matter and moisture on the calorific value of solid wastes: an update of the Tanner diagram.

Objective of the work was to experimentally determine the effect of the organic matter and moisture contents on the calorific value of organic solid wastes. Nine substrates (i.e.