Hyperspectral Estimation of Nitrogen Content in Winter Wheat Leaves Based on Unmanned Aerial Vehicles

Nitrogen (N) content is an important basis for the precise management of wheat fields. The application of unmanned aerial vehicles (UAVs) in agriculture provides an easier and faster way to monitor nitrogen content. Previous studies have shown that the features acquired from UAVs yield favorable results in monitoring wheat growth. However, since most of them are based on different vegetation indices, it is difficult to meet the requirements of accurate image interpretation. Moreover, resampling also easily ignores the structural features of the image information itself. Therefore, a spectral-spatial feature is proposed combining vegetation indices (VIs) and wavelet features (WFs), especially the acquisition of wavelet features from the UAV image, which was transformed from the spatial domain to the frequency domain with a wavelet transformation. In this way, the complete spatial information of different scales can be obtained to realize good frequency localization, scale transformation, and directional change. The different models based on different features were compared, including partial least squares regression (PLSR), support vector regression (SVR), and particle swarm optimization-SVR (PSO-SVR). The results showed that the accuracy of the model based on the spectral-spatial feature by combining VIs and WFs was higher than that of VIs or WF indices alone. The performance of PSO-SVR was the best (R2 = 0.9025, root mean square error (RMSE) = 0.3287) among the three regression algorithms regardless of the use of all the original features or the combination features. Our results implied that our proposed method could improve the estimation accuracy of aboveground nitrogen content of winter wheat from UAVs with consumer digital cameras, which have greater application potential in predicting other growth parameters.

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Estimation of Leaf Area Index of Winter Wheat Based on Hyperspectral Data of Unmanned Aerial Vehicles

IGARSS 2019 - 2019 IEEE International Geoscience and Remote Sensing Symposium ◽

10.1109/igarss.2019.8897844 ◽

2019 ◽

Author(s):

Riqiang Chen ◽

Haikuan Feng ◽

Fuqin Yang ◽

Changchun Li ◽

Guijun Yang ◽

...

Keyword(s):

Winter Wheat ◽

Leaf Area Index ◽

Unmanned Aerial Vehicles ◽

Leaf Area ◽

Hyperspectral Data ◽

Area Index ◽

Aerial Vehicles

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NITROGEN CONTENT IN SOIL AND NITRATE REDUCTASE ACTIVITY IN WINTER WHEAT LEAVES WITH THE USE OF NITROGEN FERTILIZERS

Bulletin Samara State Agricultural Academy ◽

10.12737/37333 ◽

2020 ◽

Vol 5 (2) ◽

pp. 13-19

Author(s):

Natalya Bakaeva

Keyword(s):

Nitrate Reductase ◽

Winter Wheat ◽

Nitrogen Content ◽

Nitrogen Nutrition ◽

Reductase Activity ◽

Soil Layer ◽

Central Zone ◽

Vegetation Period ◽

Nitrogen Fertilizers ◽

Wheat Leaves

The purpose of the study is increasing the efficiency of using nitrogen fertilizers and its effect on nitrate-reducing capacity of the leaf apparatus. The research was conducted in 2016-2018 in the Central zone of the Samara re-gion. The predecessor is complete fellow. Svetoch winter wheat elite seed varieties were used for sowing. Seeding was carried out in the experimental fields of the laboratory «Agroecology» of the Samara state University. Nitrate and ammonium nitrogen content in soil layer of 0-30 cm depth was estimated before planting and after plant nutri-tion with nitrogen fertilizers in regard to the growth phases (tillering, elongation and heading), the content of nitro-gen, protein and nitrate reductase enzyme activity in leaves during plant development. Dynamics changes of nitro-gen content in the soil and after fertilization with nitrogen shows that during vegetation period of plants, the amount of nitrogen is sufficient for their growth. As the phenological phases of plants change, the content of nitrogen and protein in winter wheat leaves increases, and activity of the enzyme nitrate reductase lifts, which catalyzes nitrate regeneration to nitrite. The value of the activity of the enzyme nitrate reductase in leaves can serve as a criterion for evaluating the availability of plants with the nitrate form of nitrogen. In future, the activity of this enzyme can be used as an indicator of optimizing nitrogen nutrition of plants aimed at metabolic processes. The use of various nitrogen fertilizers, and to a greater extent ammonium nitrate, increased the supply of plants with nitrogen, which is later used by them in the reutilization of nitrogen from leaves to the emerging seed, thus contributing to quality of grain.

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THE EFFECT OF MG AND S ON PHOTOSYNTHESIS PRODUCTS AND NITROGEN CONTENT IN WINTER WHEAT

Proccedings of International Scientific Conference "RURAL DEVELOPMENT 2017" ◽

10.15544/rd.2017.005 ◽

2018 ◽

Cited By ~ 1

Author(s):

Rūta DROMANTIENĖ ◽

Irena PRANCKIETIENĖ ◽

Gvidas ŠIDLAUSKAS ◽

Vita SMALSTIENĖ

Keyword(s):

Winter Wheat ◽

Nitrogen Content ◽

Chlorophyll A ◽

Dry Matter ◽

Field Experiments ◽

Matter Content ◽

Dry Matter Content ◽

Chlorophyll A And B ◽

Wheat Leaves ◽

Chlorophyll A Content

In 2013 and 2014, field experiments involving winter wheat were conducted at Aleksandras Stulginskis University’s Experimental Station on a medium-textured Cal(ca)ri-Epihypogleyic Luvisol. N150P90K120 were applied as the main fertilizers. Additionally, a foliar fertilizer including amide nitrogen, sulphur and magnesium (MgO concentrations ranging from 0.25 % to 2.5 %), (further referred to as magnesium fertilizer), was sprayed at the tillering and booting stages of winter wheat. It was found that magnesium fertilizer foliar-applied at the end of tillering and booting stages tended to increase chlorophyll a and b contents in winter wheat leaves. Chlorophyll a content in leaves significantly increased when the solution with 2.5 % concentration of magnesium had been applied at tillering and when 0.5, 1.0 and 2.5 % concentrations of the solution had been applied at booting stages. Chlorophyll b content in winter wheat leaves was significantly affected by the solutions with 0.5, 1.0 and 2.5 % magnesium concentrations at tillering and by the solutions with 0.5, 1.0, 1.5, 2.0 and 2.5 % magnesium concentrations at booting stages. The highest increase in dry matter content was recorded when 2.5 % MgO solution had been applied at booting stage. A statistically significant correlation was established between the MgO concentrations applied at tillering (r = 0.905*) and booting (r = 0.863*) stages and nitrogen content in winter wheat dry matter.

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Development of thickened semi-synthetic engine oil M-5z / 20 AERO for four-stroke gasoline engines aircraft piston of unmanned aerial vehicles (UAVs)

World of OIL Products the Oil Companies Bulletin ◽

10.32758/2071-5951-2020-0-6-44-47 ◽

2020 ◽

Vol 06 ◽

pp. 44-47

Author(s):

A.A. Moykin ◽

◽

A.S. Medzhibovsky ◽

S.A. Kriushin ◽

M.V. Seleznev ◽

...

Keyword(s):

Unmanned Aerial Vehicles ◽

Engine Oil ◽

Motor Oil ◽

Gasoline Engines ◽

State Research Institute ◽

Technical Requirements ◽

Aerial Vehicles ◽

State Research ◽

Industrial Batch ◽

The Russian Federation

Nowadays, the creation of remotely-piloted aerial vehicles for various purposes is regarded as one of the most relevant and promising trends of aircraft development. FAU "25 State Research Institute of Chemmotology of the Ministry of Defense of the Russian Federation" have studied the operation features of aircraft piston engines and developed technical requirements for motor oil for piston four-stroke UAV engines, as well as a new engine oil M-5z/20 AERO in cooperation with NPP KVALITET, LLC. Based on the complex of qualification tests, the stated operational properties of the experimental-industrial batch of M-5z/20 AERO oil are generally confirmed.

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