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In recent years, China has conducted considerable research focusing on the emission and effects of sulphur (S) on human health and ecosystems. By contrast, there has been little emphasis on anthropogenic nitrogen (N) so far, even though studies conducted abroad indicate that long-range atmospheric transport of N and ecological effects (e.g. acidification of soil and water) may be significant. The Sino-Norwegian project IMPACTS, launched in 1999, has established monitoring sites at five forest ecosystems in the southern part of PR China to collect comprehensive data on air quality, acidification status and ecological effects. Here we present initial results about N dynamics at two of the IMPACTS sites located near Chongqing and Changsha, including estimation of atmospheric deposition fluxes of NOx and NHx and soil N transformations. Nitrogen deposition is high at both sites when compared with values from Europe and North America (25–38 kg ha-1 yr-1). About 70% of the deposited N comes as NH4, probably derived from agriculture. Leaching of N from soils is high and nearly all as NO3-1. Transformation of N to NO3-1 in soils results in acidification rates that are high compared to rates found elsewhere. Despite considerable leaching of NO3-1 from the root zone of the soils, little NO3-1 appears in streamwater. This indicates that N retention or denitrification, both causing acid neutralization, may be important and probably occur in the groundwater and groundwater discharge zones. The soil flux density of mineral N, which is the sum of N deposition and N mineralization, and which is dominated by the N mineralization flux, may be a good indicator for leaching of NO3-1 in soils. However, this indicator seems site specific probably due to differences in land-use history and current N requirement. [ABSTRACT FROM AUTHOR]

Chinese pine (Pinus tabuliformis) is a conifer species endemic to the temperate, warm temperate, and semi-arid regions of China. It has important ecological and economic values, but lacks suitable molecular markers for genetic studies. In this study, we collected open-pollinated progeny seeds from four provenances: Ningcheng (Nc), Qinyuan (Qy), Weichang (Wc), and Pingquan (Pq). We sequenced the transcriptomes of open-pollinated progeny seedlings from four provenances and annotated 18,244 unigenes. We analyzed the expression of genes involved in the auxin indole-3-acetic acid (IAA), cytokinin (CTK), and gibberellin (GA) signaling pathways among the provenances. Additionally, we detected 2811 expressed sequence tag simple sequence repeat (EST-SSR) loci in 2360 unigenes, with a frequency of 14.83% and an average of one locus per 14,556 base pairs (bp). We developed 10 polymorphic primers from 67 pairs and tested them on 56 samples from the four provenances. These primers exhibited moderate to high polymorphism and distinguished all samples clearly. Our study reveals variation in growth and development among open-pollinated progeny seedlings from different provenances of Chinese pine and provides novel markers for its genetic diversity study and marker-assisted breeding. [ABSTRACT FROM AUTHOR]

Purpose The purpose of this paper is to examine the effect of adopting certified food production on chemical fertilizer and pesticide use in China.Design/methodology/approach The authors estimate fixed effect models to track the changes in agro chemical consumption at household level over time and evaluate the effect of certified food production, using an unbalanced panel data set covering 4,830 households in six provinces over the period 2005–2013.Findings On average, the authors do not find significant effects of certified food production on either chemical fertilizer or pesticide consumption among Chinese farmers. The effects are heterogeneous across villages, but the heterogeneous effects show no clear pattern that is consistent with different types of certification. The findings are robust to the use of alternative panel structure and certification indicators. The lack of knowledge about certification among farmers, the price premium and differences in regulation enforcement across regions may explain why the authors do not find negative effects on agro chemical use.Practical implications This study suggests that careful inspections and strong enforcement of certified food production is needed to ensure that the environmental goals of certified food production can be achieved and the reputation of certification in China can be improved. The inspection of certification producers and the enforcement of current regulations should be stricter for the further healthy development of certified food production in China.Originality/value This study is the first attempt to systematically evaluate the impact of food certification on the use of agro chemicals in Chinese agriculture. [ABSTRACT FROM AUTHOR]

Organic food is the development trend of food in the world today. China's green food is a kind of food with pollution-free, safety, high-quality and nutritious properties, similar to organic food in the international market. The Chinese government has paid attention to the sustainable development of agro-ecosystems under the pressures of population growth and agricultural expansion since the 1980s and began to develop a green food industry in 1990. After the development of about two decades, now the Chinese green food industry has already entered a fast-growth stage. It has reached a considerable scale and is expanding rapidly. The share of green food in the global market is continuously increasing and a two-tier certification system has been established. However, green food's further development is still facing some difficulties and problems. This paper mainly analyzes those problems and discusses reasonable solutions. Specifically, this paper first gives a detailed introduction to green food and the green food industry in China, and then analyzes the major problems impeding the further development of green food industry, such as unreasonable product structure and enterprise structure, incomplete market system and backward certification system. Finally, suggestions on product structure, enterprise structure, publicity, market, certification system and governmental policies are put forward. [ABSTRACT FROM AUTHOR]

Underground coal mining can result in land deformation (e.g., land subsidence and ground fissures), and may consequently change the soil nutrients. Soil organic matter (SOM), total nitrogen (TN), and available phosphorus (AP) are critical indicators of soil fertility and eco-restoration in mining areas. In this study, soil samples (depth: 0–20 cm) were collected twice from 20 sampling points in pre-mining and post-mining in the No.12 panel of Caojiatan coalfield, in the Loess Plateau of China. SOM, TN, and AP in soil samples were measured, and the nutrient loss was evaluated. Ten environmental factors affecting soil nutrient loss were identified from a 5-m resolution digital elevation map (DEM). The paired t-test was utilized to evaluate the differences between SOM, TN, and AP in pre-mining and post-mining soil. The mechanisms of the effects of environmental factors on soil nutrient loss were revealed based on multiple linear regression, redundancy analysis (RDA), and the random forest algorithm (RF). Ordinary kriging and RF were utilized to predict and optimize the spatial distribution of the soil nutrient loss. The results showed that significant differences existed between the SOM, TN, and AP in the pre-mining and post-mining soil. The model established by RF provided a higher accuracy in terms of fitting the correlation between soil nutrient loss and environmental factors compared to the model established by multiple linear regression, and the feature importance obtained by RF showed that profile curvature, distance to working panel margin, and surface roughness were the most significant factors affecting the loss of SOM, TN, and AP, respectively. This study provides a theoretical reference for eco-restoration, as well as soil and water conservation, in subsided lands in coalfields. [ABSTRACT FROM AUTHOR]