Effects of Meteorological Conditions on Yield and Quality of Facility Hami Melon

With different varieties of facility Hami melon(Cucumis melo var. sacchairinus) as test materials, the effects of meteorological conditions on the yield and quality of different varieties of facility Hami melon were analyzed. The results showed that among the yield and quality traits of melon, the variation degree of average single melon weight was the highest, and the coefficient of variation was 33.05%. The variation degree of leaf area index was the lowest, and the coefficient of variation was 11.00%. Through the correlation analysis of meteorological factors with the yield and quality of facility Hami melon, it was found that the quality traits of facility Hami melon were significantly positively correlated with maximum temperature and sunshine duration, and significantly negatively correlated with precipitation. The yield traits were positively correlated with maximum temperature, sunshine duration and precipitation.

新媒体时代经典阅读推广的困境及应对策略

文章分析了新媒体时代信息传播的特征及其对经典阅读的影响,认为推广主体缺位、推广形式单一、内容缺乏吸引力、推广侧重失衡等是当前经典阅读受冷遇的原因,并针对这些问题,从用户、资源和组织三个维度提出改进措施。

Evaluating the impact of sampling schemes on leaf area index measurements from digital hemispherical photography in Larix principis-rupprechtii forest plots

Background:Digital hemispherical photography(DHP)is widely used to estimate the leaf area index(LAI)of forest plots due to its advantages of high efficiency and low cost.A crucial step in the LAI estimation of forest plots via DHP is choosing a sampling scheme.However,various sampling schemes involving DHP have been used for the LAI estimation of forest plots.To date,the impact of sampling schemes on LAI estimation from DHP has not been comprehensively investigated.Methods:In this study,13 commonly used sampling schemes which belong to five sampling types(i.e.dispersed,square,cross,transect and circle)were adopted in the LAI estimation of five Larix principis-rupprechtii plots(25m×25 m).An additional sampling scheme(with a sample size of 89)was generated on the basis of all the sample points of the 13 sampling schemes.Three typical inversion models and four canopy element clumping index(Ωe)algorithms were involved in the LAI estimation.The impacts of the sampling schemes on four variables,including gap fraction,Ωe,effective plant area index(PAIe)and LAI estimation from DHP were analysed.The LAI estimates obtained with different sampling schemes were then compared with those obtained from litter collection measurements.Results:Large differences were observed for all four variable estimates(i.e.gap fraction,Ωe,PAIe and LAI)under different sampling schemes.The differences in impact of sampling schemes on LAI estimation were not obvious for the three inversion models,if the fourΩe algorithms,except for the traditional gap-size analysis algorithm were adopted in the estimation.The accuracy of LAI estimation was not always improved with an increase in sample size.Moreover,results indicated that with the appropriate inversion model,Ωe algorithm and sampling scheme,the maximum estimation error of DHP-estimated LAI at elementary sampling unit can be less than 20%,which is required by the global climate observing system,except in forest plots with extremely large LAI values(~>6.0).However,obtaining an LAI from DHP with an estimation error lower than 5%is impossible regardless of which combination of inversion model,Ωe algorithm and sampling scheme is used.Conclusion:The LAI estimation of L.principis-rupprechtii forests from DHP was largely affected by the sampling schemes adopted in the estimation.Thus,the sampling scheme should be seriously considered in the LAI estimation.One square and two transect sampling schemes(with sample sizes ranging from 3 to 9)were recommended to be used to estimate the LAI of L.principis-rupprechtii forests with the smallest mean relative error(MRE).By contrast,three cross and one dispersed sampling schemes were identified to provide LAI estimates with relatively large MREs.

Current Development Status of Cucumber Industry in Linyi City and Countermeasures for Improving Quality and Benefits

In order to expand and strengthen the cucumber industry in Linyi City of Shandong City and make it more effective in revitalizing the rural economy,the authors surveyed the current situation of the cucumber planting area,production management,fresh-keeping processing and marketing in Linyi City.Based on the survey,it analyzed the current problems in the development of the cucumber industry in Linyi City,including low level of facilities and equipment,the post-picking processing technology,the imperfect quality control system,the low degree of information and the weak degree of organization.Finally,it came up with recommendations including developing increasing modern technological innovation of facility structure and equipment,accelerating research on post-picking commercial processing technology of cucumber,accelerating the construction of product quality traceability system,promoting in-depth integration of informationization and cucumber industry,and improving the degree of organization and industrialization,to improve the quality and benefits of cucumber industry,so as to provide guidance for improving the overall quality,benefit and market competitiveness of cucumber industry in Linyi City.

Association of biochar properties with changes in soil bacterial,fungal and fauna communities and nutrient cycling processes

Soil microorganisms play crucial roles in soil nutrient cycling,carbon sequestration,fertility maintenance and crop health and production.To date,the responses of microorganisms,such as microbial activity,diversity,community structure and nutrient cycling processes,to biochar addition have been widely reported.However,the relationships between soil microbial groups(bacteria,fungi and microscopic fauna)and biochar physicochemical properties have not been summarized.In this review,we conclude that biochar affects soil microbial growth,diversity and community compositions by directly provid-ing growth promoters for soil biota or indirectly changing soil basic properties.The porous structure,labile C,high pH and electrochemical properties of biochar play an important role in determining soil microbial abundance and communities,and their mediated N and P cycling processes,while the effects and underlying mechanisms vary with biochar types that are affected by pyrolysis temperature and feedstock type.Finally,we highlight some issues related to research methodology and subjects that are still poorly understood or controversial,and the perspectives for further research in microbial responses to biochar addition.