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Angle-count sampling method for estimating forest stand volume – a practical approach
99-102Views:145Point sampling, which is also known as angle-count sampling (ACS), can be considered an efficient way of estimating the basal area and volume of forest stands. It is possible to use it in forest management: providing more accurate estimates (precision <10%) of site and stand characteristics needed for management planning. 20 black locust (Robinina pseudoacacia L.) stands were selected at final cutting age to determine the regeneration criteria based on their total volume. It was verified that at P=5% there was no difference between the main volume values of stands indicated in the relevant forest plans as well as calculated by the ACS method.
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Preliminary studies to evaluate the use of spectral data in monitoring of apple orchard parameters
37-41Views:92The introduction/application of precision agricultural technologies has more important role in various fruit growing sectors among others apple growing. Remote sensing methods can detect electromagnetic waves where the green colour of the leaf is responsible for the chlorophyll content. The absorption of chlorophyll is in the wavelength range of 450–670 nm. Samples of apple tree leaves were taken on a weekly basis from the apple orchard at Horticultural Unit of Pallag on University of Debrecen in 2019 summer. Our studies were performed on 2 cultivars (Early Gold, Golden Reinders) and the samples were processed using 2 methodologies: a non-destructive spectral method and spectrophotometric method chlorophyll and carotenoid contents were calculated, which were created into some groups and compared with the spectral values. When the plant begins to lose strong green colour and turns yellow spectral measurements show that chlorophyll content decreases as the proportion of chlorophyll-carotenoid in the plant changes. In case of grouping into intervals, it can be observed that as the chlorophyll content increases the reflectance value decreases continuously due to the strong absorption. Based on the results, close relationship between the pigments can be detected.
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Basic Research for the Development of Fertiliser Spreaders
52-57Views:79The knowledge of the physical characteristics of fertiliser particles is essential for the constructors and operators of fertiliser distributors. Among physical characteristics, the most important are the frictional and aerodynamic properties for the description of particle movement. Adjustable angled slopes, shearing boxes and various rotating disks are used to identify frictional properties. We have developed a high precision shearing box with digital force measuring cells and a distance signaller (incremental transducer) that we use for slide tests efficiently. We measured the frictional characteristics of 6 different fertilisers: the inner coefficient of friction and the coefficient of friction on ten test surfaces most commonly used in machinery, and we specified the relationship between displacement, loading and the coefficient of friction. We can conclude that the material of the frictional surface significantly influences the force of friction.
However, our experience tells us that the shearing box is not suitable for the measurement of the inner friction, since the examined particles slide on the metal surface of the shearing box in a growing extent in the course of displacement, so it does not measure the real inner friction. Therefore, in our experiment we have developed rotating shearing equipment with a constant shearing surface to identify the inner friction. We tested the equipment with fertilisers and we identified the inner frictional characteristics of 6 different fertilisers. With the developed rotating shearing apparatus we could measure the real inner friction of the particles.
To identify the aerodynamic characteristics of granules, wind tunnels and free-fall tests are used. An elutriator have been developed for our investigation. We have used fertilisers for testing the measuring equipment and we have identified the aerodynamic characteristics of 6 different fertilisers. -
Changes in the relationship between Hungarian Grey cows (Bos primigenius taurus hungaricus) and their calves in the period from calving to four months of age
85-90Views:110The ability of cows to care for their offsprings is a very important trait concerning beef cattle. Maternal instincts are highly influenced by breed, specific cow, and social and rearing environment. In 2020, at the Szamárháti farm of the Tiszatáj Public Foundation, we selected 15 dam-calf pairs and studied them for four months from the birth of the calves. We grouped calf-rearing behaviors according to strength and analyzed the related changes during the program. At the beginning of the relationship, "standing close to each other" (53%) and "suckling" (24%) characterized the pairs. After the first month, "standing or lying separated" grew by 69%, and "vocalization" by both animals fell by 66%. Even though the daily frequency of suckling decreased by 34% as the calves grew older, it remained a typical element of the relationship. Over time, the bond between the animals gradually weakened. This natural process of separation takes a month to complete.
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Usage of different remote sensing data in land use and vegetation monitoring
7-12Views:114The use of remote sensing in forest management and agriculture is becoming more prominent. The rapid development of technology allowed the emergence of database suitable for precision application in addition to the previously used low-resolution and low data content images. The high resolution, hyperspectral images are not only suitable for separating the different land use categories and vegetation types but also for examining the soil characteristics and biophysical features of plants (Blackburn and Steel, 1999; Condit, 1970). We processed a multispectral satellite image (Landsat 7 ETM+) and a hypespectral areal image (DAIS 7915) about a farm on the plains and evaluated the different image classification methods. During our examinations, we examined the geometrical and radiometrical characteristics of images first, then assigning the training areas, we determined the spectral characteristics of land use categories. We performed a multispectral analysis for checking land use, where we compared controlled and uncontrolled classification systems to check their reliability. We used areal and spectral reductions to make the classifications more accurate and to reduce the length of calculations.