Long-term no-tillage and organic input management enhanced the diversity and stability of soil microbial community

Intensive tillage and high inputs of chemicals are frequently used in conventional agriculture management, which critically depresses soil properties and causes soil erosion and nonpoint source pollution. Conservation practices, such as no-tillage and organic farming, have potential to enhance soil health. However, the long-term impact of no-tillage and organic practices on soil microbial diversity and community structure has not been fully understood, particularly in humid, warm climate regions such as the southeast USA. We hypothesized that organic inputs will lead to greater microbial diversity and a more stable microbial community, and that the combination of no tillage and organic inputs will maximize soil microbial diversity. We conducted a long-term experiment in the southern Appalachian mountains of North Carolina, USA to test these hypotheses. The results showed that soil microbial diversity and community structure diverged under different management regimes after long term continuous treatments. Organic input dominated the effect of management practices on soil microbial properties, although no-tillage practice also exerted significant impacts. Both no-tillage and organic inputs significantly promoted soil microbial diversity and community stability. The combination of no-tillage and organic management increased soil microbial diversity over the conventional tillage and led to a microbial community structure more similar to the one in an adjacent grassland. These results indicate that effective management through reducing tillage and increasing organic C inputs can enhance soil microbial diversity and community stability. (C) 2017 Elsevier B.V. All rights reserved

International Trade and Money: A Simple Classroom Demonstration

Submissions and other correspondence should be forwarded to

Xinjiang and China's security

Central Asia occupies a growing role in Chinese security policy. However, an examination of China's Central Asian policies reveals that they are essentially external projections of Beijing's vital interest of internal security in neighboring Xinjiang. Accordingly, this paper examines Xinjiang's importance for China's overall security policies. Through this examination, it becomes clear that the Xinjiang problem very much resembles that of other discontented provinces within a multinational state with a continuing imperial vocation. China's problems in Xinjiang will continue, and have important repercussions for its domestic and foreign policies, and for other key issues like Taiwan.China, internal security, defense, foreign policy, Central Asia, Xinjiang,