Soil salinity is a global issue threatening land productivity, and estimates predict that 50% of all arable land will become impacted by salinity by 2050. Consequently, it is important to have a fundamental understanding of crop response to salinity to minimize economic loss and improve food security. While an immense amount of research has been performed assessing corn (Zea mays L.) and soybean [Glycine max (L.) Merr.] response to salinity, there are few, if any, comprehensive reviews compiling previously published literature. This review provides a detailed description of our current knowledge on the impacts of salinity on corn and soybean growth and development. Both osmotic stress and specific ion toxicities with respect to corn and soybean are addressed. Additionally, potential areas of future research are recommended.Core Ideas Review of salinity's effects on corn and soybean growth and development. Impacts of osmotic stress and specific ion toxicities discussed. Potential areas of future research addressed.

Recovery of belowground microbial community structure is important for reclamation success. In this study, the recovery of soil microbial community structure in cool‐season grass dominated and sagebrush dominated reclaimed sites were examined using chronosequences ranging in time following reclamation from <1 to 26 yr. Phospholipid fatty acid (PLFA) analysis was used to characterize changes in microbial community structure with time. Initial effects of surface mining resulted in reductions of total microbial biomass and diversity, with the greatest influence on saprophytic fungi and arbuscular mycorrhizal fungi relative to undisturbed soils. The total concentration of PLFA biomarkers increased after 14 yr in soils established under cool‐season grass communities and 5 yr in soils colonized by sagebrush communities. Canonical multivariate analysis of variance indicated that soil microbial communities under reestablished sagebrush were more similar to one another than those under cool‐season grasses. In general, microbial biomarkers of reclaimed soils recovered to predisturbance levels within 5 to 14 yr, which indicated that the most important phase of microbial community recovery occurs between 5 and 14 yr after reclamation.

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Reclaimed coal mine lands have the potential to sequester atmospheric carbon (C); however, limited information exists for the western USA coalfields. This study was carried out on two chronosequences (BA-C 3 grasses and DJ-shrubs) of reclaimed sites at two surface coal mines to determine the effects of vegetation, soil texture, and lignin content on soil total organic carbon (TOC) accumulations. In the BA chronosequence, TOC increased over 26 years at an average rate of 0Á52 Mg C ha À1 yr À1 in the 0-30 cm depth and was significantly correlated with clay content. Comparison between < 1 and 16-year-old stockpile soils indicated TOC content did not differ significantly. In the DJ chronosequence, TOC content in the 0-30 cm depth declined from 31Á3 Mg ha À1 in 5-year-old soils to 23Á4 Mg ha À1 in 16-year-old soils. The C:N ratios suggested that some (up to 2Á0 per cent) of the TOC was potentially derived from coal particles in these reclaimed soils. Soil total N (TN) contents followed a similar trend as TOC with TOC and TN concentrations strongly correlated. Lignin contents in TOC of all reclaimed soils and topsoil stockpiles (TSs) were higher than that of nearby undisturbed soils, indicating the recalcitrant nature of TOC in reclaimed soils and/or possibly the slow recovery of lignin degrading organism. Results indicated that TOC accumulations in DJ were largely controlled by its composition, particular lignin content. In BA sites TOC accumulation was strongly influenced by both clay and lignin contents.

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Sustainability of mined-land reclamation is of growing importance, with over 600,000 ha of the Appalachian coal region disturbed since 1977. Long-term evaluation of soil under various reclamation strategies is also important. Aggregation and organic matter (OM) influence both soil structure and function and can be of use in evaluating reclaimed systems. The objective of this study was to examine these two parameters in a long-term experiment (27 years) where various types (control-CON, topsoil-TS, sawdust-SD and biosolids-BS) and rates of soil amendments (biosolids: BS-22, BS-56, BS-112 and BS-224 Mg ha À1 ) have been applied. Macroaggregates (>250 μm) comprised >95% of total aggregation across all treatments, indicating the importance of this size class for soil development. Macroaggregate carbon (C) and nitrogen (N) pools contributed more to stabilization of OM in these soils than microaggregate pools. All BS treatments contained higher concentrations of aggregate C (96·8-127 g C kg À1 aggregate) and N (6·80-8·22 g N kg À1 aggregate) relative to CON; however, mass of C and N did not vary among application rates. Though few differences were expressed in C and N pool sizes among treatments, there was some indication that amendments impact reclaimed sites early in soil development (~< 10 years), while vegetation may exert more dominance in subsequent years. It is important to select appropriate management strategies to favor not only the establishment of desirable vegetation but also preservation of soil macroaggregate structure to improve long-term nutrient supply, physical soil properties and potential C-sequestration in reclaimed soils.