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
The plastic film mulch has the function of increasing soil temperature and preserving moisture, and it also can suppress weeds and maintain soil structure. Because of these special physical and chemical properties, agricultural mulching is extensively applied to cotton and other crops. Xinjiang is currently the largest cotton planting region in China, and all cotton cultivation involves film mulching. However, because plastic film itself is difficult to degrade and without scientific management and recovery in long-term use, a large amount of residual plastic film is left in the fields after harvesting, which has caused serious pollution problem to both the soil and the ecological environment. The mechanical collection of the plastic mulch is one of the effective ways to resolve plastic mulch pollution at present. Therefore, it is significant and urgent to study the residual film recovery methods and operation machines. Many kinds of mulching residues recovery machines have been developed and used, but there are some problems with the machines such as bad adaptability, low recovery rate, poor work efficiency in removing the collected film, and plastic films being easy to wind in cotton straw chopping, which needs further improvement for the machines. With a view to solving the above problems, a new method of operation step by step was proposed, which could collect plastic film in strip at first and then recover it, and a cotton straw chopping and plastic film strip-collection combined machine was designed. The machine mainly consisted of suspension device, power transmission system, straw chopping device, straw conveying device, strip-collection device, and stripping device. Compared with the existing cotton straw chopping and plastic film collection combined machines, the machine proposed in this paper was simplified and efficient. The machine adopted the way of throwing cotton stalk into a certain height and distance to create a condition to separate cotton stalk from the residual film. Moreover, because of the ground profile modeling, this machine could be adapted to complex operating environments and operating requirements, and had a good performance on the strip-collection ratio. It could not only realize the straw chopper returning and the straw separation with plastic film, but also collect plastic film in strip with one operation, which ensured that it was easy to recover plastic film and recycle it. Based on the underlying theory analysis and experimental study, its basic structure and main parameters were determined, and the rational kinematic relationship among the knife-roller speed, the forward speed of unit, and the speed of strip-collection device was obtained by experiments. Field trials were conducted in Manas County of Xinjiang. The experiment results showed that the working efficiency could reach 1.15 hm2/h, the plastic film collection stripe ratio was 92.6%, the straw chopping qualification rate was 97.5%, and the film-straw separation ratio was 90.5%, when the machine operating speed was 5–7 km/h, the cutter shaft speed was 1 880 r/min, and the speed of strip-collection device was 150–160 r/min, which could satisfy not only the agricultural requirements but also national standards. The research results can provide a reference to solve the problem of plastic film pollution in cotton-growing areas of China.
Fabric air distribution system, one of the terminal equipment in air conditioning system, can achieve uniform linear air supply and affect air jet distribution through unique orifices in the duct. It is widely used in the field of agriculture. In this study, a wet curtain cooling fan-fiber duct system was used in a beef cattle barn in summer and designed to meet with the jetting wind speeds at beef standing height (1.3 m to floor) of 1.5, 2.3, 3.1, 3.9 m/s from duct 1, duct 2, duct 3, and duct 4 respectively via different orifice schemes. The study was carried out with Simmental crossbred cattle in a semi-open barn. Four wet curtain cooling fans with air volume of 18 000 m
3/h and total pressure of 190 Pa were used as the cooling source. Four fabric ducts (
Φ = 0.813 m) connecting with cooling fan were mounted above the feed manager wall with bottom height of 1.8 m from the floor. The operation time of the cooling system was from 10:00 to 19:00 based on the local environmental conditions and farm management. The zone thermal environmental parameters under the four ducts, and some physiological indexes of cattle were collected to evaluate the effect in alleviating heat stress and find out the best opening scheme. The results showed that there were no significant differences of the average temperature and relative humidity among the four duct cooling zones (
P > 0.05) during the measurement period; the average temperature of the barn decreased by 2.1 °C compared with the outside (
P < 0.05); and the relative humidity in every duct cooling zone was less than 85%. The average wind speed was the highest in duct 3 cooling zone (1.32 m/s) and the lowest in duct 1 cooling zone (0.62 m/s) (
P < 0.05). Meanwhile, the average carbon dioxide concentration was the lowest in duct 3 cooling zone and the highest in duct 1 cooling zone (
P < 0.05). The cattle respiration rate negatively correlated with wind speed, with the lowest respiration rate in duct 3 cooling zone (42 breaths/min) and the highest in duct 1 cooling zone (52 breaths/min). The results indicated that the application of a wet curtain cooling fan-fiber duct in a beef cattle barn was effective in relieving cattle’s heat stress, especially the duct with a designed jetting wind speed of 3.1 m/s at cattle standing height (1.3 m from floor) had the best effect.
Northeast China is the most important base of commodity grain, and in this region the temperature is low, the wind is quite strong, the precipitation is quite little, and the water resource is quite deficient, so the crops face with serious problems of lack of water resource and dry soil in spring. To address the problems of shallow soil plough layer, serious soil hardening and huge resistance during deep scarification, through combining the key technologies of deep scarification, ridging and fertilization, a kind of combine operation machine was designed, which was named 2ZZ-3 type deep scarification-terrace ridge-fertilization combine intertillage machine. This machine suspended on the tractor through the three-link hitch, and it was mainly composed of the upper hitch, the lower hitch, the frame, the controlling depth device, the deep loosening ridging device, the fertilization opener and the fertilizer box. During the process of operation, it could finish the deep scarification, ridging and fertilization at the same time. The machine used the disc knife to cut the soil block because of the serious hardened and impervious soil. The controlling depth wheel could ensure not to destroy the seedling attributed to the distance between frame and ground, and the fertilizer reached the fertilization shovel cross the fertilization apparatus to finish the fertilization. Finally, the deep scarification and ridging device finished the deep scarification and soil ridging in the furrow. The deep scarification shovel was chisel-tooth shovel; its breaking soil ability was strong, and it suffered low working resistance. Both the controlling depth device and the ripping device could make adjustment during the actual working status in the field. Through the field test of 2ZZ-3 type deep scarification-terrace ridge-fertilization combine intertillage machine, a three-factor and three-level orthogonal test was carried out with setting the tractor forward speed, deep scarification depth and hiller opening angle as the factor, and the injuring rate and soil specific resistance as the evaluation index. The results showed that the importance order of all the factors which influenced the injuring rate and soil specific resistance was the deep scarification depth, hiller opening angle and tractor forward speed. When the deep scarification depth was 25 cm, the hiller opening angle was 60° and the tractor forward speed was 5 km/h, the machine would reach the optimal combination, and the injuring rate average was 3.31% and the soil specific resistance average was 1.97 N/cm
2. Through the field test, the working performance of the machine was perfect, all the indexes reached the agriculture machine and agronomic requirement, and deep scarification and ridging links were working at the same time, which reduced the power consummation and working resistance. The research provides the reference for the construction of matching implements for reasonable plough layer of dry land of brown soil zone in Northeast Plain of China.
Because of the fast development of Chinese urbanization, the intense growth of mankind activities, and the global warming, the inland lake pollution problems have become more serious and complex, and the inland lakes are becoming more eutrophic, suffering from both point and non-point pollutions, and exposing to both endogenous and exogenous pollutions. The deterioration of water quality has severely hindered sustainable social and economic development of nearby cities. Eutrophication is not just the result of natural process, but the aggregated result of the interaction and mutual influences between natural process and human process. As the "eyes" of water protection and management, water quality monitoring is the premise for the forecast of Cyanobacteria outbreak and the assessment of bloom intensity. As technology advances, the monitoring tools and measuring indicators become increasingly diverse. In the meantime, the measurement accuracy is also constantly improving. In the domain of water quality monitoring, the combination of position sensors and wireless sensor networks makes the observations with high density, high precision and continuity possible. In addition, such methods can simultaneously collect both water quality data and surrounding environmental data, which can be used to simulate the interaction between the internal and external factors of water pollution as well as the mechanism of pollution process. The Cyanobacteria Bloom of inland lake has the characteristics of suddenness, randomness, and regionalism. The paper proposed a Cyanobacteria Bloom dynamic monitoring and spatial-temporal process simulation method based on wireless sensor networks (WSNs) and geographic information system (GIS). Firstly, multi-parameter sensor array was designed using water quality sensors in order to acquire real-time water quality data, and the monitoring node was composed of 4-layer architecture, including monitoring layer, data storage layer, modellayer, and application layer; secondly, the improved grey model and back propagation (BP) artificial neural network were combined to forecast the
Cyanbacteria Bloom in 24 h. This model incorporated both environmental factors (precipitation, wind speed, and wind direction) and the internal water environment factors (nitrogen, phosphorus, chemical oxygen demand, permanganate, chlorophyll, dissolved oxygen, pH value, and temperature); thirdly, with the advantage of spatial analysis, GIS was used to describe the spatial-temporal processing of Cyanbacteria; finally, the simulation experiment results showed that the correlation coefficient achieved up to 0.995. Moreover, we conducted the empirical experiment in Dianchi Lake, Yunnan, China using the proposed method, and the determination coefficient was 0.86 and the predicting error was 9.74. The field experiment results showed that the method discussed in the paper had certain universality and could provide theoretical basis and data support for protecting and controlling the lake environment.
