Please select the most similar patent number from A, B, C and D. Which number is?
A nutrient solution management technique based on the length of a leaf of a greenhouse tomato, comprising the following steps: 1, subtracting from the leaf length of a feature leaf of a greenhouse tomato a standard leaf length for the feature leaf, excess water and fertilizer supply being indicated if the result is greater than zero, insufficient water and fertilizer supply being indicated if the result is less than zero, and adequate water and fertilizer supply being indicated if the result is equal to zero; 2, subtracting from the current electric conductivity value of a nutrient solution used in watering the EC value of the nutrient solution in a water and fertilizer deficit condition, multiplying the difference by the number of days the nutrient solution has been used in watering, and the result being the amount of nutrients of the nutrient solution excessively or insufficiently applied, and utilizing the average growth rate, a, of the feature leaf to deduce the current electric conductivity value of the nutrient solution used in watering; and 3, determining, on the basis of the amount of nutrients of the nutrient solution excessively or insufficiently applied, a final electric conductivity value of the nutrient solution for adjustment, and watering the crop with the adjusted nutrient solution. Only the length of the feature leaf of the greenhouse tomato needs to be measured, one-time investment incurred is low, and the measurement is simple and easy.
A: A nutrient solution distribution device and a method for monitoring concentration of a nutrient solution. The nutrient solution distribution device comprises: a plurality of sub-nutrient tanks (102), for storing the nutrient solution and distributing the nutrient solution to plants; a reservoir nutrient tank (104), connected to each of the sub-nutrient tanks (102) for delivering the nutrient solution to each of the sub-nutrient tanks (102); a plurality of sensors (106), for detecting concentration values of the nutrient solution in each of the sub-nutrient tanks (102) and the reservoir nutrient tank (104); a nutrient solution formulation device (108), connected to the reservoir nutrient tank (104) and for delivering the nutrient solution to the reservoir nutrient tank (104); and a controller, connected to the reservoir nutrient tank (104), each of the sub-nutrient tanks (102), each of the sensors (106) and the nutrient solution formulation device (108). The nutrient solution distribution device and the method for monitoring the concentration of the nutrient solution allow the concentration values of the nutrient solution in each of the sub-nutrient tanks and the concentration values of the reservoir nutrient solution to meet concentration criteria, preventing the concentration of the nutrient solution in the sub-nutrient tanks or the reservoir tank from decreasing due to plant absorption or water evaporation, ensuring normal plant growth.
B: A multi-scale habitat information-based method and device for detecting and controlling water and fertilizer for crops in seedling stage: performing fusion analysis on multi-scale features of the water and fertilizer stress of crops on the basis of crop canopy-scale three-dimensional laser scanning information, foliage-scale polarization-hyperspectral imaging information, and micro-scale micro-CT scanning information; combining the real-time feedback of the temperature, humidity, illumination and substrate moisture content within a crop growing greenhouse; by means of multi-information fusion modeling, comprehensively determining and feeding back the water and fertilizer stress of the crops as well as water requirement and fertilizer requirement information, and providing policy information for the amount of fertilization and irrigation. On the basis of the policy information for water and fertilizer, and on the basis of frequency conversion speed control technology and pipeline constant pressure control technology, a water and fertilizer control system controls the pressure of a pipeline and the flow rate of the fertilizer by means of dynamically controlling the rotation speed of an irrigation pump and a fertilizer pump, and thus, combined with the dynamic feedback of an EC value, the accurate control of a liquid fertilizer ratio and irrigation volume is achieved.
C: A plant cultivation device for a garden. The plant cultivation device comprises a cultivation table (1). The cultivation table (1) is internally provided with a grid of holes (2). Each of the grid of holes (2) is provided with plant cultivation mud. A transmission slide rail (4) is mounted at one side of the cultivation table (1). Two ends of the transmission slide rail (4) are respectively provided with a transmission motor (5). One of the transmission motor (5) is connected to a watering device via a transmission sprocket-wheel (6). The watering device comprises a water storage bottle (8) and a watering tube (7). The water storage bottle (8) is provided above the transmission sprocket-wheel (6). The watering tube (7) is provided above the grid of holes (2) via the transmission sprocket-wheel (6). A nutrient solution is filled into the water storage bottle (8) of the plant cultivation device for the garden. The transmission sprocket-wheel (6) drives the watering tube (7) to move to apply, in a small area, the nutrient solution to a seedling (3) being cultivated in the plant cultivation mud. The transmission motor (5) drives the transmission sprocket-wheel (6) to move inside the transmission slide rail (4) to drive the watering tube (7) to move, performing large-area watering with the nutrient solution. The watering operation is easy, achieving mobile watering with an adjustable watering area.
D: An ecological cultivation system with a high pressure fine water mist ,comprising a nutrient solution supply system and a cultivation frame (12), the root (2) of a crop seedling (15) being wrapped within a planting sponge body (14), the planting sponge body (14) being fixed on the cultivation frame (12), the nutrient solution supply system comprising a nutrient solution storage tank (1), a filter (3), a magnetizer (4), a low pressure ball valve (6), a high pressure pump (7), a high pressure ball valve (9), and a high-pressure fine water mist sprayer (10), a liquid outlet of the nutrient solution storage tank (1) being connected to a water inlet of the high pressure pump (7) by means of the filter (3), the magnetizer (4), and the low pressure ball valve (6) being connected in series, and a water outlet of the high pressure pump (7) being connected by means of the high pressure ball valve (9), to the high-pressure fine water mist sprayer (10) provided within the cultivation frame (12). Said system is easy to produce, easy to operate, and it is easy to perform automatic control and solid cultivation, improving the utilization rate of a greenhouse.
Answer: B