Soil organic matter, rather than temperature, determines the structure and functioning of subarctic decomposer communities

Abstract

Terrestrial ecosystems in the Arctic are adapted to harsh abiotic conditions with low soil temperatures and nutrient levels, especially nitrogen (N), and are considered particularly vulnerable to climate change (Overland et al., 2020). As such, soil warming due to climate change could lead to more favorable soil conditions in the Arctic, reducing metabolic constraints on belowground organisms and increasing their activity, which should alter nutrient and carbon (C) dynamics (Nielsen & Wall, 2013). Such changes in the soil environment are intricately linked to aboveground processes as soil communities drive nutrient cycling, and nutrient availability in turn regulates plant and associated aboveand belowground consumer assemblages (reviewed in Bardgett et al.,

Effects of long-term climate trends on the methane and CO2 exchange processes of Toolik Lake, Alaska

“…We argue that the biological processing of carbon-rich substrate that becomes available for decomposition as the tundra soil warms (e.g., Robinson et al, 2022) is key for understanding future trends in GHG fluxes (see also Wu et al, 2013), whereas the variability and long-term trends of the physical and meteorological variables primarily affect the timing when higher or lower than average fluxes are observed. When all aspects are taken into account, we see no strong evidence that a tipping point will be reached to change the status of the system substantially (e.g., source to sink).…”

“…Stronger winds, and stronger winds in combination with warmer 10-cm soil temperatures, also exert a negative effect on CO 2 fluxes on the order of −10% (Table 1). From other ecosystems it is also known that the near-surface soils are the most important substrate for respiration, in combination with soil temperature but with a dominance of availability of organic matter (e.g., Robinson et al, 2022). In arctic tundra there is substantial organic peat available across the upper soil profile, and thus the importance of the 10cm conditions (and not the moss or 5 cm temperature) for respiration and decomposition may be most relevant as soils warm and eventually thaw in the Arctic.…”

Temporal effects of climate and soil fertility‐mediated maize yield and its sustainability: A case study in subtropical China

“…Persistent high temperatures and/or precipitation during growing and non‐growing seasons may expedite agricultural harvests and reduce the tolerance of plants to harsh external environments (Brown et al, 2018). Furthermore, soil fertility influences climate‐soil potential productivity to a considerable degree, particularly in areas with poor soil fertility (Robinson et al, 2022; van Grinsven et al, 2022). Therefore, further elucidation of the effects of climate, soil fertility, and their interactions on grain yield and sustainability is required to better identify the patterns of sustainable agricultural development.…”

“…Despite the importance of soil nutrients to grain yield and its sustainability (Robinson et al, 2022), climate should not be overlooked (Bocci et al, 2020). The climate is a comprehensive element that not only directly impacts the metabolic of crop development processes (e.g., photosynthesis and organic matter synthesis/transport) but also clearly affects crop growth via the absorption and transfer of soil water and fertilizer (Luo, 2011).…”

“…Previous research has largely concurred that rising temperatures will lower agricultural production (Zhao et al, 2017). Changes in soil temperature often influence plant phenology and physiology, while modifying the functional roles of microbial populations (Robinson et al, 2022). For instance, a meta‐analysis indicated that higher temperatures increased terrestrial ecosystem nitrification and denitrification on a global scale (Dai et al, 2020).…”