中国连栋温室黄瓜周年生产能耗分布模拟

Simulation analysis of distribution of energy consumption for year round cucumber production in multi-span greenhouse in China

温室作物周年生产单位产量的能耗是进行温室投资风险评估和优化温室气候控制的重要指标。为明确中国温室作物周年生产单位产量能耗分布规律,该文以Venlo型连栋温室和温室主栽作物黄瓜为研究对象,选取中国有代表性的224个气象观测站点25a(1981-2005年)每日平均气候资料(每日最高最低气温、水汽压、日照时数和平均风速),利用温室能耗预测模型和作物生长模型,模拟预测在商业化生产中常用的两种不同的温室温度(白天和夜间温度控制目标分别为控制策略一:24℃与19℃,控制策略二:20℃与15℃)和CO2体积分数(增施:1000μL/L,自然通风不增施:350μL/L)控制策略下,连栋温室黄瓜周年生产所需的能耗和黄瓜的潜在产量。在此基础上,进一步计算每单位黄瓜产量所需要的能耗,并利用GIS技术及反距离权重插值方法获得空间上连续分布的栅格数据,得到中国连栋温室黄瓜周年生产单位产量能耗分布图。结果表明,中国温室周年生产黄瓜单位产量能耗总体趋势是从低纬度地区向高纬高海拔的寒冷地区增加。两种温度控制策略下各地的黄瓜单位产量能耗差异在8%以内,但增施CO2可以降低各地的黄瓜单位产量能耗达29%～67%,低纬度地区降低幅度大于高纬高海拔区。中国温室能耗主要受室外气候和温室温度控制目标影响;在两种温室温度控制策略下,黄瓜潜在产量主要受室外光照条件和室内CO2浓度影响。增施CO2能够大幅提高黄瓜产量,是增加温室作物产量和提高能耗利用率的有效手段。该研究结果可为中国不同区域连栋温室投资风险评估和从能耗角度优化温室环境调控提供支持。

Distribution of energy consumption per unit yield of greenhouse crops is essential information for assessing the risk of greenhouse investment and optimizing greenhouse climate control in different regions. In order to predict the energy consumption per unit yield of greenhouse crops,a Venlo type greenhouse and cucumber crop were used in this study. Firstly,hourly meteorological data （air temperature,global radiation,water vapor pressure and wind speed） were derived based on the 25 years （1980-2005） average meteorological data （daily maximum and minimum air temperature,water vapor pressure,sunshine hours and wind speed） of 224 weather stations in China. The hourly meteorological data were then used as input of a greenhouse energy consumption model and a crop growth simulation model to calculate the greenhouse energy consumption,cucumber potential yield and the energy consumption per unit yield of cucumber under two different strategies for greenhouse temperature （daytime and nighttime set-point for temperature control for strategy I：Tset,d=24 ℃ and Tset,n=19℃,for strategy II：Tset,d=20 ℃ and Tset,n=15℃） and CO2 （CO2 enrichment：1000 ？L/L,natural ventilation CO2：350 ？L/L） control used for commercial greenhouse cucumber production. Based on the simulation results,maps of the distribution of energy consumption per unit yield of greenhouse cucumber in China under the two different strategies for greenhouse temperature and CO2 control conditions were obtained by using GIS software. The results showed that energy consumption per unit yield of greenhouse cucumber increased from the south to the north and higher altitude regions. Under the two strategies for greenhouse temperature control,CO2 enrichment reduced greenhouse energy consumption in a greater degree in the south than in the north and higher altitude regions. With the two temperature control strategies,the variation of energy consumption per unit yield of greenhouse cucumber was less than 8%,but with temperature control strategy II and CO2 enrichment,it could be reduced up to 29%-67% （from the north and higher altitude regions to the south）. Greenhouse energy consumption in China mainly depend on outside climate conditions and set-point for temperature control. Under the given two temperature control strategies,the potential yield of greenhouse cucumber is mainly affected by outside solar radiation and inside CO2 concentration. CO2 enrichment can greatly increase crop potential yield,and can be an effective approach to increase the use efficiency of greenhouse energy consumption. The results obtained in this study can be used for assessing the risk of greenhouse investment and optimizing greenhouse climate control in different regions of China.