A Study On Biomass Accumulation Of Cucumber Plants In Controlled Enviroment

In order to establish a cucumber development model in controlled environment,the processes of greenhouse vegetable model such as CURGROW,TOMGRO and etc.has been learned, including mathematical models of photosynthesis production,distribution and accumulation of dry matter,development of plant parts,water conservancy and biomass production,as well as other submodels.Simulations have been done for this model by Matlab R2008a and Microsoft Excel in Windows environment.Optimal schemes were proposed for different culcivation purpose.1.Jingdian NO.1 cumcuber breed being chosen as experimental materials was cultivated in Venlo controlled greenhouse and manpower climate house.Growth and development and greenhouse datas were measured and recorded timely.Experimental data was used to determine model parameters,which are specific leaf area of 0.028,leaf hot spacing 20.87℃d,the initial utilization of light 0.338μmolm^-2s^-1/Jm^-2s^-1,maximum photosynthetic rate of 4.1gCO₂m^-2h^-1,the conversion of carbohydrates to the dry coefficient of 0.69.2.A model was established,which icluding photosynthesis,respiration,crop growth and development stage,the distribution of dry matter accumulation,leaf area index and fruit fresh weight model.Among them,account light,temperature,CO₂ concentration and the impact of soil moisture were taken into account in the photosynthesis model;the dry weight of fruit and the impact of soil moisture were taken into account in fruit biomass weight model.After validation,the model simulated and measured values of absolute average relative error are:photosynthesis＜17%,leaf sequence＜12%,yield＜12%,which indicating that model has certain accuracy.3.In the Windows environment,Matlab R2008a and Excel software were used to simulate the model.Surface and contour analysis methods such as simulated were used in order to maximize the output and profits for the cultivation and management targets.Production environment has been chosen to maximize the optimal combination of control parameters of the theoretical,which are the temperature of 31.3℃,CO₂ concentration 598.9ppm,soil moisture 0.91cm³/cm³,light intensity 1000μWm^-2.An optimal scheme was detemined, according to different prices and environmental regulation and control inputs,using contour-based search-control strategy for the environment.According to the strategy of environmental regulation,the ultimate profits were nearly 2 times more than ever.