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In China, rain-fed (dryland) agriculture is practiced in the North China Plain as well as parts of northeast and northwest China, accounting for 51% of the total arable land. However, this region is facing an increasing rate of environmental degradation, soil erosion, and water shortage. To combat this environmental degradation, no-till (NT), as the primary principle of conservation agriculture, has been widely adopted as a sustainable agriculture practice due to its ability to control land degradation, sequester soil organic carbon (SOC), and mitigate climate change. Thus, NT offers an option to improve soil water conservation and soil quality in rain-fed areas of China. The objective of this chapter is to re-evaluate the current performances of NT farming management and describe the positives and negatives of NT for the control of soil erosion and the increase of crop production in rain-fed agricultural regions of China. Based on this review, NT can reduce wind-blown sediment, save water due to less soil disturbance, maintain a higher proportion of retention and continuous pores, enhance the infiltration rate, and decrease water evaporation, especially by mulching with crop residues. In addition, NT can eventually realize the potential to improve grain yield and the local economy. An 11-year case study conducted in Inner Mongolia showed an obvious increase by 7.4%, 17.9%, and 4.0% in SOC concentration in the NT treatment compared to subsoiling with residue retained (ST), rotary tillage with residue retained (RT), and plow tillage with residue retained (PT), respectively. In addition, the greatest biomass yield was observed for NT, which was 1.9%, 10.5%, and 9.1% higher than that under ST, RT, and PT, respectively. Although NT has the potential to solve problems that the rain-fed agricultural area faces, there are many barriers to its widespread adoption, such as the lack of standard technology and suitable equipment compared to traditional agricultural practices. In addition, various and complex crop rotations, inter-cropping systems, and crop species require corresponding strategies. These barriers constrain the rates of adaptation of NT by farmers in this rain-fed region. Therefore, developing suitable technologies are necessary to popularize NT practices among farmers in rain-fed agricultural areas of China.

In order to determine the effect of mixed salt stress on the germination rate of naked oat and protective enzymes of its' seedling, in this study, using artificial culture box of climate, oat varieties (Yanke 1, Canadian 9, Big oat, Canadian 8, Canadian 6 and Baoluo) were cultivated in mixed salts solution. The results showed, with the increasing of concentration of double salts, the germination ratio and plant height decreased, semi-lethal concentration was between 1.5% and 2.6, utmost concentration was between 2.3 and 3.8%, respectively; the CAT activity of Big oat decreased, but that of other varieties increased first and then decreased, the peak value appeared when concentration of double salts was between 0.4 and 0.6%, respectively. And with the increasing of the concentration of double salt, POD activity and SOD activity of six oat varieties increased first and then decreased and its highest value appeared when concentration of double salts was between 1.2 and 1.8% respectively; the proline contents of all varieties increased, while the MDA contents decreased first and then increased and its minimum value appeared when concentration of double salts was 0.2%. To sum up, under the condition of salt stress, it was likely because of increasing of protective enzyme activity and proline contents to make salt tolerance of oats higher and salt tolerance of different varieties showed significant difference. The salt tolerance order showed that Yanke 1>Canadian 9>Baoluo>Big oat>Canadian 8>Canadian 6.

Traditional tillage (TT) in the North China Plain has maintained grain productivity in the past 50 years. Nonetheless, it has also been a major contributor to global greenhouse gas emissions, biodiversity and soil fertility loss, soil degradation, and even desertification. Permanent raised beds (PRB) have been proposed as a viable solution to achieve sustainable farming in this plain. The effects on soil chemical properties of the PRB treatment and two other treatments, namely, no-tillage and TT treatments, were measured between 2005 and 2011 in the annual double cropping regions of the North China Plain. The soil properties significantly (P 1.35) were significantly (P < 0.05) higher than those under no-tillage and TT. In the cropping zone of PRB, the bulk density was significantly reduced by 14.4%, whereas soil organic carbon, total nitrogen, phosphorus, and potassium and available nitrogen, phosphorus, and potassium in the 0- to 10-cm soil layer were significantly increased by 24.8%, 78.8%, 121.9%, 81.8%, 46.2%, 7.0%, 2.9%, respectively, in comparison with those of TT treatments. Winter wheat and summer maize yields in PRB also underwent a slight increase. Permanent raised beds seem to be an improvement on current farming systems in the North China Plain and valuable for the sustainability of farming in this region.