基于WSN的集中通风式分娩猪舍环境参数时空分布特性

Spatiotemporal distribution characteristics of environmental parameters of centralized ventilation delivery sows based on WSN

为研究集中通风式分娩猪舍环境参数的时空分布特性,以云南省某规模化种猪场为试验对象,利用无线多源多点远程监测系统(Wireless Sensor Network,WSN),对地沟管道进风、中央排风式分娩母猪舍养殖环境开展了环境参数监测试验,并进行统计分析。试验结果表明,在试验期间内,分娩舍内不同时间段之间的温度(00:00-06:00、06:00-12:00、12:00-18:00以及18:00-00:00的平均温度分别为22.98、23.78、24.44和23.61℃)具有显著性差异(P<0.05),相对湿度与温度随时间变化呈现负相关性,相对湿度的峰值点为82.31%,温度场分布均匀性比湿度场好,NH3浓度分布均匀性比CO2浓度差。NH3浓度在舍内能被有效的维持在低水平范围,各监测区域的浓度远小于指标值(20 mg/m3),NH3和CO2会呈现出在边角积聚现象。温湿度指数较低,舍内平均温湿度指数(Temperature-humidity Index,THI)水平的峰值点为75.30,生猪出现热应激的概率较低。利用WSN系统,对集中通风式分娩舍环境参数进行多源多点远程监测,分析分娩舍环境参数时空分布特性,为分娩舍通风模式与环境调控策略优化设计提供参考。

In order to study the spatial and temporal distribution characteristics of various environmental parameters of centralized ventilation in pigsties, a centralized ventilated delivery house by numerical simulation in Yunnan province was taken as the test object, and a wireless multi-source and multi-point remote monitoring system(Wireless Sensor Network, WSN) was used to carry out the environmental parameter monitoring test and statistical analysis on the breeding environment of the delivery pigsty. Experimental results showed that during the period of experiment, there were significant differences in temperature between different time periods in the delivery pigsty(P<0.05, the average temperature of Time: 00:00-06:00, 06:00-12:00, 12:00-18:00 and 18:00-00:00 was 22.98, 23.78, 24.44 and 23.61 ℃), the time periods of 00:00-06:00 and 12:00-00:00 were significantly different from other time periods respectively. There was no significant difference in relative humidity and CO2 concentration between 12:00-18:00 and 18:00-00:00, but they were significantly different from the other two time periods. The change of NH3 concentration was significant only during the time period from 12:00 to 18:00(P<0.01). There were significant differences in the temperature variation among the three areas inside the delivery pigsty(P<0.05), and the average temperature in the area with 35 cm horizontal height was the highest(24.26 ℃) and the most stable(CV=2.14%). There were no significant difference in the change of relative humidity with horizontal height of 90 cm and 35 cm.. The distribution of NH3 and CO2 concentration in the three areas of the delivery pigsty was also divided into three groups, with significant differences among them(P<0.01). Relative humidity and temperature changed over time negative correlation, the temperature in each area of the piggery can be controlled below a high critical level, the peaks of the relative humidity was 82.31%, the temperature field distribution uniformity was better than humidity field, and the distribution of NH3 concentration was more uneven than that of CO2. NH3 concentration could be effectively maintained at a low level in the delivery pigsty, the concentration in each monitoring area was far less than the index value(20 mg/m3), but the concentration of CO2 was at a high level both in time and space. In the plane with a height of 90 cm, the temperature distribution was high in the middle and low in the four sides. The relative humidity tended to be average values in the left area, and the lowest in the right side wall area. NH3 and CO2 would appear to accumulate at the corner. The temperature humidity index was low, the peak point of average THI(Temperature-humidity Index) inside was 75.30, and the probability of heat stress of pigs was low. In this study, Wireless Sensor Network system was used to conduct remote monitoring of environmental parameters of piggery from multiple sources and multiple points, and the distribution characteristics of environmental parameters of centralized ventilation piggery were analyzed, which provided a reference for the optimal design of environmental control of farrowing house under this ventilation mode.