Coated controlled-release fertilizers (CRFs) have been widely applied in agriculture due to their increased efficiency. However, the widespread and a lot of coated CRFs application may leave undesired coating residues in the soil due to their slow degradation. Limited information is available on the effects of substantial residual coatings on the soil bacterial community. By adding 0, 5, 10, 20, and 50 times quantities of residual coating from conventional application amount of resin and water-soluble coated CRFs, we studied the responses of soil properties and bacterial community composition to these two residual coatings in black soil. The results showed that the resin and water-soluble coatings did not essentially alter the properties of black soil or cause dramatic changes to bacterial diversity within the test concentration range. The residual resin and water-soluble coatings also did not distinctly alter the relative abundance of the top ten bacteria at phylum level. Heatmap results suggested that the treatments were basically clustered into two groups by concentration rather than types of coating material. Pearson correlation analysis showed that the Simpson’s diversity index of the bacterial community was significantly correlated with microbial biomass carbon (MBC, r=0.394, P<0.05), and the richness index abundance-based coverage estimator (ACE) of the bacterial community was significantly correlated with microbial biomass nitrogen (MBN, r=0.407, P<0.05). Overall, results of this study suggested that substantial residual resin and water-soluble coatings with 0–50 times quantities of residual coating from conventional application amount of coated CRFs did not generate obviously negative impacts on the bacterial community in black soil.

Ecological risk assessment of metals in soils is important to develop the critical loads of metals in soils. Phytotoxicity is one of the endpoints for ecological risk assessment of soils contaminated with metals. The sensitivity of eight Chinese plant species (bok choy, mustard, tomato, green chilli, paddy rice, barley, spinach and celery) to copper (Cu) and nickel (Ni) toxicity in two Chinese soils was investigated to assess their potential use for ecological risk assessment in the region. The results showed that bok choy and mustard were the two most sensitive species to Cu and Ni toxicities. Assessment of metal accumulation by the plants demonstrated that bok choy shoot had the highest bioconcentration factor (BCF, the ratio of metal concentration in plant shoots to metal concentration in soil). Given the importance of bok choy to agricultural production in Asia, it is therefore important that these sensitive plant species are included in species sensitivity distributions for ecological risk assessment of Cu and Ni in soils.

China has experienced dramatic changes in food consumption patterns over the last three decades. However, there are different opinions regarding the future trends in consumption. By adopting the well-developed partial equilibrium model-China Agricultural Policy Simulation Model (CAPSiM), the demand for livestock products and the main feed crops over 2011–2030 is predicted and analyzed. It is found that China’s per capita consumption of livestock products will continue to rise during this period, even though its growth rate will slow down gradually. Meanwhile, the expansion of livestock production will pose great challenges for feed supply in China. More accurately, China will be confronted with feed security rather than grain security in the future.

The purpose of this paper is to document the likely impacts of climate change on China’s agriculture and the current adaptation efforts made by government and farmers. The review of literature shows that climate change will have a significant impact on agriculture, primarily through its effect on crop yields. The extent of predicted impacts highly depends on the crop, the CO2 fertilization effect assumption and adaptation abilities. Market response to the production shocks resulting from climate change will lessen the impacts on agricultural production predicted by natural scientists. On adaptation, the government’s major efforts have been in the developing new technologies, reforming extension system and enhancing institutional capacity. Farmers do adapt to climate change, but their adaptation measures cannot fully offset the negative impacts of climate change. The paper concludes and makes implications for future studies.

Alkali stress can cause severe crop damage and reduce production. However, physiological processes involved in alkali stress in oat seedlings are not well understood. In this study, physiological responses and yield of oat to alkali stress were studied using the alkali-tolerant oat genotype Vao-9 and the alkali-sensitive oat genotype Baiyan 5. The results were: (i) low concentrations of alkali stress (25 and 50 mmol L-1) significantly reduced the yield and grain weight while increased the oat grain number per spike. A negative correlation between yield and malondialdehyde (MDA) content at the jointing and grain filling stages and positive correlations between yield on one hand and superoxide dismutase (SOD), and peroxidase (POD) activities on the other at the jointing stage were observed. There was a positive correlation between MDA and soluble sugar at the grain filling stage; (ii) soluble sugar content was increased at the jointing and grain filling stages and decreased at the heading stage by alkali stress; (iii) alkali stress increased the SOD activity during the heading and grain filling stages, and increased the POD activity at the heading stage. As compared to the control, the increase of MDA contents in alkali-treated oat was observed, during the jointing, heading and grain filling stages; (iv) under alkali stress, the oat genotype Vao-9 showed higher antioxidant enzyme activity and lower soluble sugar contents during the heading stage, and lower MDA contents than those in the oat genotype Baiyan 5 under alkali stress. The result suggested that the high ROS scavenging capacity and soluble sugar levels might play roles in oat response to alkali stress.

Food safety standard draws increasing concerns on agricultural trade throughout the world. This paper aims to assess the impact of maximum residual limit standard (MRL) of chloromycetin on honey exporting from China. To achieve this objective, the paper discusses the trends of China’s honey production and export practices, analyzes changes on MRL of chloromycetin adopted by major importing countries, and use a gravity model to estimate the impact of MRL of chloromycetin on China’s honey export. The results show that despite the rapid growth of China’s honey production, honey export has declined significantly since 2000. The major reason of declining honey export was mainly due to the more stringent food safety standards indicated by MRL of chloromycetin imposed by importing countries on their honey imports.

Rational application of nitrogen (N) fertilizers is an important measure to raise N fertilizer recovery rate and reduce N loss.A two-year field experiment of rice-wheat rotation was employed to study the effects of N fertilization modes including aN fertilizer reduction and an organic manure replacement on crop yield, nutrient uptake, soil enzyme activity, and numberof microbes as well as diversity of microbes. The result showed that 20% reduction of traditional N fertilizer dose of localfarmers did not significantly change crop yield, N uptake, soil enzyme activity, and the number of microbes (bacteria,actinomycetes, and fungi). On the basis of 20% reduction of N fertilizer, 50% replacement of N fertilizer by organic manureincreased the activity of sucrose, protease, urease, and phosphatase by 46-62, 27-89, 33-46, and 35-74%, respectively, andthe number of microbes, i.e., bacteria, actinomycetes, and fungi by 36-150, 11-153, and 43-56%, respectively. Further,organic fertilizer replacement had a Shannon’s diversity index (H) of 2.18, which was higher than that of other modes ofsingle N fertilizer application. The results suggested that reducing N fertilizer by 20% and applying organic manure in theexperimental areas could effectively lower the production costs and significantly improve soil fertility and biologicalproperties.