Foreword: Degradation and evolution of Mollisols under different management practices and climate change

Abstract

Efforts are being dedicated to refining agricultural management practices and policies regarding ecosystem restoration. Agricultural management practices, such as reduced soil tillage, rational fertilization, crop rotation, and crop residue or livestock excreta management, enhance the sustainability and resilience of agroecosystems in Mollisol regions.This special section of the Soil Science Society of America Journal includes eight peer-reviewed papers, with six field studies and two laboratory incubation experiments. Those papers address the biogeographic distribution of N-related microbes, and the current research on the effect of agricultural management practices on soil hydraulic properties, nutrient cycling, and biotic and abiotic mechanisms in Mollisol-based agroecosystems. Collectively, these articles provide a systematic understanding of the ecosystem characteristics and resilience, and C and N cycling patterns in Mollisol agroecosystems. They also identify controlling factors that will shed light on the optimization of sustainable management and utilization of Mollisols.A brief summary of the studies in this special section is provided below:• Denitrifiers control the stepwise reduction processes of NO 3 − to N 2 in global N cycles. Among these, the reduction

Soil Quality Mediates the Corn Yield in a Thin-Layer Mollisol in Northeast China

“…Black-soil degradation has drawn increasing attention in China in recent years [42,43]. Soil erosion [44], a lower carbon input than output [6], and soil compaction [45] are the three most important factors accounting for the degradation of mollisols. The roles of the three factors in the SQ evaluation were reflected by the BST, SOM, and SPR indexes in the present study.…”

“…However, unreasonable farming-system-induced anthropogenic degradation has played an increasingly important role in recent years. For example, intensive tillage and crop-residue removal has resulted in soil erosion [5] and dehumification [6] in the Chinese black-soil region. The average black-soil thickness (BST) has decreased from 60-70 cm in the 1950s to the current thickness of 20-30 cm [7].…”