Effects of digestate application depth on soil nitrogen volatilization and vertical distribution

This study investigated the effect of the digestate application depth on soil nitrogen volatilization and vertical distribution in black loam soil and sandy loam column.The contents of soil moisture,TKN(total Kjeldahl nitrogen),ammonium nitrogen,nitrate nitrogen,and the extent of ammonia volatilization were tested by applying digestate at depths of 0 cm,2 cm,6 cm,10 cm,15 cm and 20 cm,respectively.The experimental results showed that ammonia volatilization mainly occurred in the first 10 days and reduced significantly when the application depth was deeper than 10 cm.At the same application depth,compared with the black loam,the nitrogen loss in sandy loam through ammonia volatilization was less,and the penetration depth of nitrate nitrogen and ammonium nitrogen were all deeper.In the same soil,nitrate nitrogen penetrated deeper than ammonium nitrogen at all application depths.

Gelatin encapsulation of chloropicrin and 1,3-dichloropropene as fumigants for soilborne diseases in the greenhouse cultivation of cucumber and tomato

Combined use of chloropicrin （Pic） and 1,3-dicloropropene （1,3-D） is as effective as methyl bromide （MB） at controlling soilborne diseases in many trials and commercial uses. However, Pic and 1,3-D are both highly volatile and may pose strong exposure risks to humans and the environment. A gelatin capsule formulation containing Pic and 1,3-D has been developed to reduce exposure risks to workers and bystanders and improved application safety. We conducted two experiments in tomato and cucumber greenhouses located in Beijing and Qingdao, China, to study the efficacy of Pic plus 1,3-D gelatin capsules applied at different dosages and soil depths. Results indicated that both injection and gelatin capsules of Pic plus 1,3-D provided good control of soil nematodes and reduced disease index of Fusarium wilt and root-knot nematode. Plant yield of tomato and cucumber treated with gelatin capsules was similar to MB treatment. Based on our results, gelatin capsules applied at a soil depth of 15 cm provided better control of soilborne diseases and led to higher fruit yield compared to an application depth of 5 cm. In conclusion, a gelatin capsule of Pic plus 1,3-D is a promising and novel formulation, which not only shows good efficacy in controlling soilborne diseases, but also reduces potential exposure risks of fumigants.

BREAKING THE MONOLITH： STRATEGY, VARIETY, AND PERFORMANCE OF ENTERPRISE INFORMATION SYSTEMS

This paper intends to understand the form of implementations of Enterprise Information Systems （EISs）. EISs are usually provided as packaged software products. Due to the diversities of implementations, EISs are often characterized by their system architectures. A conceptual framework is proposed to delineate the diversity and dynamics of EIS implementations. This framework is constituted of three components, EIS strategy, variety, and process-level performance （SVP）. In particular, the variety of implementations is defined by two constructs, application scope and application depth. A Partial Least Squares structural equation modeling approach is applied to test the hypotheses according to the survey data from 223 project reports of EIS implementations in China. The results show that the EIS strategy and variety can both affect the performance of the implemented EISs. Specifically, application depth has an important mediating effect on the relationship between EIS strategy and performance. EIS strategy and application depth are breakthrough points to improve the performance of the implemented EISs. These findings suggest that the variety plays a central and effective role in the analysis of EIS implementations. This SVP framework highlights the interconnections among its components and captures the form of EIS implementations.