Effect of temperature on microbial residue dynamics in a temperate farmland soil

Microorganisms mediate soil organic carbon (SOC) turnover, and microbial residues contribute a significant portion to SOC storage in temperate agroecosystems. However, little is known about the direct effect of temperature on microbial residues associated with SOC sequestration/decomposition. We assessed microbial residue dynamics in a 28 d incubation conducted at four temperatures (5, 15, 25, and 35 °C). Microbial residues did not change with time from 5 to 25 °C. However, at 35 °C, fungal residues decomposed significantly with time, and the decomposition rate was higher than SOC. Considering the important contribution of fungal residues to stable-C pool, our findings indicated warming may be detrimental to C stability in this temperate soil.

Taxonomic composition of weed vegetation in the southern and middle Urals and zonal features of its control in maize crops

As a result of expeditionary-route studies, the impoverishment of the composition of the segetal flora in maize crops was established when moving from the North-West to the South-East of the Ural region: from 37 species in the forest-meadow and mountain-forest zones to 10 in the steppe zone. Zonal features of the composition of weed communities associated with the hydrothermal gradient consist in the mutual substitution of annual monocotyledonous and dicotyledonous species with a stable contribution of perennial dicotyledons, as well as the replacement of mesophytic weeds with xerophytic species of the same families. A comparison of cross-spectrum herbicides effectiveness in the forest-steppe and forest-meadow zones showed the advantages of a post-emergent preparation with soil effect of Meister Power. In temperate soil fertility in the Southern area of the region, it is economically feasible to use post-emergent herbicides without soil effect, in Northern areas with stable moisture – soil ones.