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The unique black soil resources and natural environment of Jilin province provide the proper conditions for the growth of ginseng-the king of herb. Ginseng industry has effectively promoted the development of medical and health industry, and brought considerable economic income for ginseng farmers. However, long-term continuous cropping of ginseng causes the chemical, biological, and physical properties deterioration of soil, which influences the yield and the quanlity of ginseng, and results in the occurrence of replant obstacle. Identifying the malignant soil factors in continuous cropping obstacles, then analyzing the evolution process, and putting forward the improvement strategies is the primary task of ginseng research at present. This paper reviews the influence of ginseng cultivation on the physicochemical property, nutrient, enzyme activity, microecology and ecotoxicity of the soil, and the achievements of improving ginseng soil by chemical and biological techniques and methods in recent 10 years. [ABSTRACT FROM AUTHOR]

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The spatial patterns of field arthropod communities are an essential part of ecology and can provide fundamental data regarding field ecological processes and reveal the mechanism of ecosystem biodiversity maintenance. This study investigated the spatial distribution pattern of field insect communities to detect the spatial relationships between insect communities in farmland. The study site was located at the Dehui Agro-ecological Experimental Station of Black Soil, Jilin, China. Insect communities and environmental factors were sampled at 121 uniformly distributed points in a 400 × 400 m plot in August, September, and October 2015. The analysis revealed that insect communities from June to October demonstrated significant spatial correlation, and 6085 samples of 47 species and 47 families in 11 orders were collected from the insect community in the farmland. The farmland insect community structure changes and dynamic changes of nutritional function groups occur with time. According to the 400 x 400 m plot, the diversity of farmland insect communities and functional groups is maintained at a relatively high and stable level. In this study, a total of 6085 samples of corn farmland insects were obtained using the fluke method and direct observation method, including 11 orders, 26 families and 47 species, 4 absolute dominant populations, 6 main dominant populations, and 37 other populations. These studies can provide help for pest control in the spring corn area of Northeast China. [ABSTRACT FROM AUTHOR]

• IQI-NLS index performed better than other soil quality model in BSZJLC. • The determined MDS for BSZJLC included BD, CEC, SOM, AN, TK, ACu, and AFe. • The soil quality in study area was dominated by moderate grades. • Effects of environmental factors on soil quality has local characteristic. Soil quality assessment is an effective way to improve understanding of the heterogeneity of soil quality and to encourage the adoption of proper agricultural practices. The object of this paper is to select the most effective soil quality indices and the minimum data set (MDS) for the black soil zone of Jilin Province, China, and analyze the association between soil quality and the environmental control. Taking the croplands of the black soil zone of Jilin Province, China, as the study area, different combinations of scoring methods, indices, and data set methods were compared. A minimum data set, based on the integrated quality index derived from non-linear scoring methods (MDS IQI-NLS index), was then selected via principal components analysis to assess the soil quality of the study area. The determined minimum data set for the study area included bulk density, cation exchange capacity, soil organic matter, alkali-dissolvable N, total K, extractable Cu, and extractable Fe. The results showed that the soil quality in the study area was of dominantly moderate grades (grades II, III and IV), accounting for approximately 90% of the total as well as the minimum data set, and the soil quality index increased from the northwest to the southeast. Group analysis was applied because different combinations of environmental factors play different roles in different sub-regions. The analysis results showed that the most important factors affecting soil quality in group 1 (in decreasing order of importance) were: mean annual temperature, DEM, amount of straw return, parent material, and topographic wetness index. For group 2 they were: parent material, annual precipitation, mean annual temperature, chemical fertilizer, DEM, amount of straw return. This analysis proves to be an effective way to determine the factors that affect the spatial distribution of soil quality. [ABSTRACT FROM AUTHOR]