Transactions of the Chinese Society of Agricultural Engineering, the 1st in Agricultural Engineering, is supervised by China Association for Science and Technology, and sponsored by Chinese Society of Agricultural Engineering. It aims to introduce the latest scientific achievements and developing trends of Agricultural Engineering and provides the academic developments abroad and domestic of the discipline. The scope covers agricultural water-soil engineering, agricultural information and electrical technology, agricultural products processing engineering.
The journal is included in EI, JST, Pж(AJ), CA and CSCD.
Editor-in-Chief Zhu Ming
Deputy Editor-in-Chief Wei Xiuju Zhang Ruihong Xi Weimin Wang Liu Wang Yingkuan Li Pingping Ying Yibin Tong Jin Yun Wenju Zhao Chunjiang Kang Shaozhong
Soil moisture (SM) is one of the main reasons for the decline of predictive accuracy of soil attributes (organic carbon and salt,
etc.) in using the spectrum analysis method. By comparing the two methods of external parameter orthogonization (EPO) and non-negative matrix factorizing (NMF), we explored a method and technology route of removing the effect of SM and improving the estimation precision of soil salt content (SSC) based on hyperspectra. Firstly, we used Kenli district of Dongying City in Shandong Province as the research area, and took 96 soil samples in the fields. The samples’ hyperspectra in situ and indoor after air-drying were measured respectively by spectra radiometer, and then transformed to the first deviation. The contents of soil salt and moisture were measured in laboratory. Then, the spectral characteristics of SSC and the effect of SM on it were analyzed by comparison. Next, the EPO and NMF were respectively used to correct and fuse the soil spectra in-situ (Situ-spectra), and to remove the SM effect and form the EPO correction spectra (EPO-spectra) and the NMF fusion spectra (NMF-spectra) of the Situ-spectra. Finally, the estimation models of SSC were built respectively by the multiple step linear regression (MSLR) and the partial least squares regression (PLSR) based on the Situ-spectra, EPO-spectra and NMF-spectra, and were verified and compared to analyze the changes of the SSC prediction precision. The results indicated that the SSC was high, the SSC gradient was obvious, and the dispersion degree of SSC was high. However, the SM content was about 30 folds of the SSC in the study area. The correlation between soil salt and spectra was better at the wavelength ranges of 1 440–1 660 nm, 1 830–1 860 nm, 1 960–2 110 nm. The SM had great effects on the Situ-spectra and SSC spectral characteristics. Therefore, it is necessary to remove SM impact. The EPO method could reduce the correlation between spectra and SM in most spectral regions, and at the same time weaken the correlation between spectra and soil salt in local wavelengths. In comparison, the NMF method could effectively reduce the correlation between spectra and SM, and increase the correlation between spectra and soil salinity. Both the EPO and NMF could improve the accuracy of the SSC estimation based on Situ-spectra. After adoption of EPO, the validation coefficient of determination (
R2) was increased by 0.08–0.09, and the relative prediction deviation (RPD) was increased by 0.08–0.69. At the same time, after adoption of NMF, the validation
R2 was increased by 0.27–0.38, reaching above 0.80, and the RPD was increased by 1.04–1.06, reaching above of 2.37. Thus, the result of NMF was more significant than that of EPO for the removal of the SM effect. The method of EPO combined with PLSR or NMF combined with MSLR could be used as the technical route of removing the SM effect and building the SSC correction model. The results can effectively promote the quantitative remote sensing extraction and real-time and in-situ monitoring of the saline soil information.
The seeds cannot fully sprout owing to the seed quality, sowing precision, and environmental difference. In order to get the accurate information of the null plug holes and the boundary of plug holes and provide the basis for automatic seedling supplement device, an automatic seedling supplementing test-bed was developed with aseedling shortage detecting system and a seedling supplementing system as core components. The seedling shortage detection system was composed of a hardware system for image processing, which included a CMOS industrial camera, a controller, and a computer, and a software system programmed in MATLAB. The color images (RGB images) of
Arabidopsis thaliana plug seedlings with the ages of 25 and 35 days were acquired with the automatic seedling supplementing test-bed. The gray-level images of seedlings and plug holes were obtained by graying the color images applying different linear transformations to three color components of R, G, and B. Applying Otsu algorithm, binary images of the gray-level images of seedlings were obtained through thresholding. Then, the morphological corrosion operation and dilation operation of the binary images were carried out by the disk 2 × 2 type structure operator. By marking single connected domain, analyzing the characteristics of connected domain and removing the isolated area, the noises in the binary images were removed and the feature images of the seedlings were extracted from the background effectively. The feature images of plug tray were acquired by removing the feature images of plug seedlings from that of the plug tray according to the extracted seedling information and denoising. Then, statistics on the peak value, peak width, and standardizing structure of plug tray were made according to the row and column pixel of binary images of plug trays, so that the boundary of plug holes were determined accurately. The statistics of the pixel of the seedling image in each plug hole were made to determine whether the hole was short of seedlings according to the feature images of the seedlings, the position, and the boundary information of the plug holes. The results showed that the statistics values of the seedling image pixel of the plug holes with the
A. thaliana plug seedlings of 25 and 35 days were 1 895 to 4 572, and 3 386 to 8 710, respectively, while the statistics value of the seedlings image pixel of the plug holes without seedlings was 0. There was significant difference in the statistics value of the seedling image pixels between the plug holes with seedlings and the null plug holes. The testing results of the missing plug tray hole were the same as the actual situation, and the statistical value of seedling pixels corresponded to the projection area of stem and leaf. According to the threshold values of seedlings at different growth stages, the undeveloped seedlings could be marked for removing, so the seedling early stage was the super time for the detection of the null plug hole and the determination of the undeveloped seedlings. The accuracy of judging the null plug holes and the seedling holes with the
A. thaliana plug seedlings of 25 and 35 days was all 100% applying the detection device. The accurate determination of position of the null plug hole provides basis for automatic supplementing system taking out the substrate without seedlings, removing dysplasia seedlings and supplementing healthy seedlings with the same age.
As land is an important livelihood resource for rural households, land transfer means that rural households intend to break inherent livelihood pattern and seek alternative livelihoods through the integration of livelihood capital to ensure their livelihood security. In this paper, we aimed to determine the livelihood capital integration characteristics of rural household, including its direction, intensity, and benefit. Taking three villages of Shuangkui Town, Hechuan District, Chongqing City, China as a case study, 267 questionnaires of rural household renting their farmland were collected prior to land transfer in 2013 and after land transfer in 2017, respectively. In this paper, firstly, according to the employed industry and its change, rural households were divided into five categories: stable pure households, non-agricultural pure households, stable part-time households, non-agricultural part-time households and stable off-farm households. Secondly, based on the livelihood capital system that included six subsystems: human capital, physical capital, productive capital, living capital, financial capital, and social capital, the difference of livelihood capital among different types of households was analyzed. Finally, the radar chart, livelihood capital disturbance index, and growth index were applied, respectively, to evaluate the integration direction, intensity, and benefit of households’ livelihood capital before and after the land transfer. The results indicated that the livelihood capital totalities of stable off-farm households, non-agricultural part-time households, stable part-time households, non-agricultural pure households and stable pure households were 3.248, 3.142, 2.967, 2.460, and 2.274, respectively, in 2013. Besides, non-agricultural pure households and non-agricultural part-time households had more human capital, living capital, financial capital and social capital, while stable pure households and stable part-time households dominated in physical capital and productive capital before land transfer. It was apparent that the livelihood condition was the basis of livelihood transformation of rural households. The results also showed that the human capital, living capital, financial capital and social capital of non-agricultural pure households and non-agricultural part-time households increased, while the physical capital of stable pure households and stable part-time households rose. Therefore, for livelihood capital intensity direction, non-agricultural pure households and non-agricultural part-time households were inclined to the integration of human capital, financial capital, and social capital, while stable pure households and stable part-time households focused mainly on the integration of productive capital. However, there was no obvious difference in the intensity direction of livelihood capital for stable off-farm households. In addition, livelihood capital disturbance index was in the descending order of non-agricultural pure households (0.169), non-agricultural part-time households (0.144), stable pure households (0.124), stable part-time households (0.105) and stable off-farm households (0.098). It showed that the livelihood capital integration intensity of non-agricultural households was higher than that of stable style households. Moreover, the livelihood capital growth index was in the descending order: non-agricultural part-time households (0.135), non-agricultural pure households (0.120), stable part-time households (0.094), stable off-farm households (0.093), and stable pure households (0.088), respectively. Thus, the livelihood capital integration benefit of non-agricultural households was also higher than that of stable style households. From this research, we concluded that path inertia law existed in the livelihood capital integration process of rural households. That was, certain livelihood capital pattern was able to trigger off the particular livelihood strategy which solidified the corresponding livelihood capital pattern, which was positive for non-agricultural part-time households and non-agricultural pure households but not for stable part-time households and stable pure households. The results would provide references for the establishment of policies on accelerating land transfer to ensure livelihood sustainability of households. Besides, the interactive mechanism between farmer’s livelihood capital integration and land transfer would be better understood.
Rice is one of the main food crops in the world, and rice yield accounts for 37.3% in total food yields in China, so the technology to increase rice yields becomes a research hot point. The seed soaking and pregermination technology is an important technology in rice cultivation, especially in the cold region of China. Rice is very susceptible to frost damage, and therefore rice needs an accumulated temperature compensation to prolong the rice growth stage. Rice seeds can acquire the effective accumulated temperature of 100 program-controlled through the seed soaking and pregermination technology. The whole process of seed soaking and pregermination has three stages: seed soaking, high-temperature treatment for breaking seed coat (seed budding), and promoting bud growth under moist conditions (seed germination). The temperature range of the seed soaking stage is from 11 °C to 13 °C, the second stage is the seed budding process which needs a temperature range from 31 °C to 33 °C, and the third stage is the seed germination process which needs a temperature range from 26 °C to 28 °C. However, in the present condition, there are several serious problems in large-scale rice soaking and pregermination in the cold region: The upper and lower water temperatures are not uniform during the soaking process, and the aerobic respiration of seeds is not good in a large-scale sprouting tank. These problems are easy to cause low germination rates of seeds or thin weak seedlings. Further, these problems will cause severe loss in yield and quality of rice. To solve these problems, we studied the activation mechanism of seed germination firstly. This mechanism included the effect of soaking temperature and time on the physiological activity of rice seeds. Secondly, the temperature and humidity monitoring system of the sprouting tank was introduced based on the internet of things technology. This system included three parts: infrastructure used for placing the seeds, electric heater, circulation pipe line, solenoid valve, and so on; intelligent monitoring system used for production data acquisition, data display, data storage and production equipment control based on sensor technology and computer technology; remote monitoring and data service system used for remote virtual control of production equipment and managing of multiple production bases based on network technology. This system could be used for automated management of sprouting tank environment parameters. Thirdly, we divided the temperature field into three layers: upper layer, middle layer, and lower layer, and we simulated the temperature field of the sprouting tank with MATLAB software. The simulation results of the temperature field showed that the control accuracy of the system was high, and the temperature uniformity was good in the sprouting tank. The results of the sprouting experiment also showed that the germination rate could reach 97.79%; the degree of uniformity and haleness were improved substantially; the temperature control accuracy could reach ±0.2 °C; the water level control accuracy could reach ±0.3%. This research provides a kind of new technical support for the improvement of the rice soaking and pregermination, and at the same time, this technology shows better social and economic benefits.
Insufficient soil moisture content and accumulated temperature of the plow layer during springtime tillage in Northeast China severely restrict soybean root growth and soybean development. Aiming at these issues, bionics structure design and theoretical analysis were methodologically combined to design an earthworm-like multi-function opener, which had the functions of loosening, furrowing and compaction. This machine could simulate the movement of the earthworm to loose surface soil of plow layer and compact subsoil of seed ditch, which could build favorable seedbeds with soft surface soil and the compacted subsoil, and then significantly raise the soil temperature and soil moisture content of plow layer, significantly promoting soybean emergence and development. Parameter optimization experiments and regression analysis methods were adopted to study how key structure parameters and operating speed of earthworm-like multi-function opener affected the average soil temperature (0–100 mm), average soil moisture (0–100 mm), and emergence time of soybean. The experiment data obtained were assessed by the analysis of variance (ANOVA) and a quadratic regression model was set up for optimization by response surface methodology with Design-Expert. Analysis showed that the operating speed, scarification mechanism bump height and number of crests of corrugated disk had significant effects (P < 0.01) on the average soil moisture content (0–100 mm), average soil temperature (0–100 mm), and average emergence time. Operating speed had significant interaction with bump height and number of crests, respectively and there was no interaction between the bump height and number of crests. The average soil moisture content (0–100 mm) decreased with the increase in the advancing operating speed, and the decline trend gradually decreased. The average soil moisture content (0–100 mm) decreased with the increase in the bump height and the number of crests, and the decline trend gradually decreased. The average soil temperature (0–100 mm) increased with the acceleration of the operating speed, and the upward trend slowed down gradually. With the increase in bump height and the number of crests, the average soil temperature (0–100 mm) presented a rising tendency, and the rising trend decreased gradually. With the increase in operating speed, the average emergence time decreased first and then increased. The average emergence time of soybean increased after slight decrease with the increase in the height of bump. As the number of crests increased, the average emergence time decreased at first, and then rose. Earliest average emergence time was taken as main optimization index to obtain the optimal parameters by using MATLAB software based on the analysis of the test results and the model fitting. It was found that the optimal parameters of earthworm-like multi-function opener were as follows: operating speed of 8 km/h, bump height of 6 mm, and number of crests of 15. Compared with the traditional single-disk and double-disk opener, the earthworm-like multi-function opener could increase the average soil water content (0–100 mm) by 5.92% and 4.86%, raise average soil temperature (0–100 mm) by 0.5 °C and 0.4 °C, and advance soybean emergence time by 0.5 day and 0.92 day, respectively. The results showed that the scarification furrowing mechanism which simulated the biological behavior of earthworms could effectively loosen the plow layer soil and increase the soil porosity in the plow layer so as to effectively improve the soil temperature. Meanwhile, the pressure-regulating mechanism could significantly accelerate the absorption of moisture from the soil beneath the plow layer by compacting subsoil of seed ditch, and then increase the soil moisture content of the soil in plow layer. This new machine can improve the physical properties of the soil in the tillage layer, and ultimately achieve the purpose of promoting soybean development. This is a powerful guarantee for production of soybean per unit area in Northeast China.
