Device and monitoring method for in-situ research on ammonia exchange in crop canopy

Abstract

The invention discloses a device for researching crop canopy ammonia exchange in situ at a farmland and a monitoring method. The device comprises an air-proof cultivation cover and a dilute acid carrier, wherein an air inlet pipe is arranged on the side wall, close to the zero depth, of the cultivation cover; an air exhaust hole is formed in the top of the cultivation cover; the air exhaust hole is connected with a vacuum pump; and brackets for fixing the dilute acid carrier are arranged at the ends, close to the zero depth and the air exhaust hole, in the cultivation cover respectively. The diameter and the height of a growth box of the device can be adjusted according to the size and the height of a monitored plant; and dilute acid for soaking sponge can be phosphoric acid, sulfuric acid and oxalic acid. By the device and the monitoring method, canopy ammonia exchange of farmland crops in a vigorous growing stage (particularly after fertilization) and ammonia emission of the farmland crops in a growing later stage can be researched; during monitoring, humiture in the cover is almost the same as the humiture in a natural environment, so mists in the cover are avoided and influence on growth of rice can be prevented; therefore, the repeatability of rice is high and the variation coefficient is generally less than or equal to 10 percent; and the device is easy to operate.

Description

technical field [0001] The invention belongs to the technical field of ammonia exchange monitoring of plant canopies in agricultural production, and in particular relates to a device and a monitoring method for in-situ research on ammonia exchange of crop canopies in the field. [0002] Background technique [0003] With the rapid growth of the world's economy and population, man-made reactive nitrogen emissions have risen sharply, and agricultural production activities have caused a large amount of ammonia to enter the atmosphere. The increase in ammonia concentration has caused a series of ecological and environmental problems, such as water eutrophication, algal blooms, Soil acidification, loss of biodiversity, and the greenhouse effect. Farmland is an important emission source of ammonia in the atmosphere. Ammonia volatilization is an important way to lose ammonia after fertilizers are applied to farmland. Gaseous ammonia can also be used as nitrogen nutrition for plant...

AI Technical Summary

Problems solved by technology

Farmland is an important emission source of ammonia in the atmosphere. Ammonia volatilization is an important way to lose ammonia after fertilizers are applied to farmland. Gaseous ammonia can also be used as nitrogen nutrition for plants. Plant canopies play a central role in the biological earth cycle of ammonia. , it can absorb ammonia in the air, and can also emit ammonia into the air. It is an important transfer station for gaseous ammonia. However, there is no suitable method at home and abroad to monitor the canopy ammonia exchange in situ in the field, which not only hinders The scientific evaluation of fertilizer loss and farmland air pollution also affects the formulation of related agronomic measures for energy saving, emission reduction and high yield and high efficiency. It is particularly important to monitor the ammonia exchange in the canopy of farmland crops

[0004] Currently available methods for studying canopy ammonia exchange include: (1) leaf chamber method, that is, plant leaves are placed in a small chamber, and artificially controlled Environmental factors, the amount of ammonia exchange in leaves can be judged by the change of ammonia concentration, which is suitable for studying the mechanism and influencing factors of ammonia exchange, but it is powerless for the research on ammonia exchange of plants growing in the natural environment, especially fertilized farmland crops (2) The micrometeorology method is commonly used abroad to study ammonia emissions from farmland, but this method has very strict requirements on the stability of meteorological conditions, the uniformity of the surrounding environment, and the measurement area (greater than 1 hectare). Moreover, the instruments and equipment are expensive, and the most important thing is that the micrometeorology method can only measure the ammonia emission of the whole system, and cannot distinguish the contribution of the soil and the canopy, and the ammonia exchange volume of the canopy is still a black box; (3) the closed room method, At present, domestic farmland ammonia volatilization loss research mostly adopts this method, but the current airtight chamber is too small to include the canopy. In fact, the ammonia emission on the soil surface of the farmland is measured. For the evaluation of farmland ammonia emission research involving the canopy also powerless

Therefore, existing methods either cannot study canopy ammonia exchange in isolation or in situ in the field

Images