Search
Search Results
-
Hail data analyses
99-103.Views:130Long term data of hail events of three meteorological stations (Budapest, Debrecen and Szeged) were investigated. The hail event frequencies show significant differences in the time period 1901–2000 when the first and the second half of the century are compared. The frequencies of hail events are higher in the first half of the century in case of Debrecen and Szeged while it is higher in the second 50 years for Budapest. None of the frequencies of hail events in between 2001–2008 are significantly higher, though the average of precipitation fell during these events is higher except for Szeged. We have found that the results about the monthly distribution of hail events differ from the ones in the literature; the ratio of hail events is significantly less in the vegetation period.
-
Economic aspects of applying hail protection nets in apple plantations
99-101.Views:238The up to date intense apple growing in Hungary is capable to produce yearly about 500-1000 thousand Ft/ha income, which means that the investment of 4 000–5 000 thousand Ft is returned by producing 10-20% net income. The economic balance may, however, be upset by the damage caused by hail, quantitative and qualitative, with an apparently increasing frequency experienced in each third or fourth year. Estimates prove that each hail causing 50% damage may reduces the income proportionately to the capital by 1.5–2.0 percent points, which means a serious threat for the economy of apple production. According to calculations, a plantation producing 30–40 t/ha yields would not be able to raise incomes compensating the investment of 7.0–10.0 million Ft/ha, let alone the frequencies of hail damages. Consequently, 50–60 t/ha yields are needed to become successful, and in planning of new plantations those high yields are aimed with hail nets. An additional difficulty is represented by a lack of financial resources to install hail protection nets.
-
Effects of excessive weather on the micro-climate of apple plantations under the hail protection nets
81-85.Views:343The general utilisation of hail nets is spreading all over the world and in Hungary too. Hail nets are at present the only tool, which
is able to prevent heavy hail damage in agricultural crops. Besides its numerous advantages, there are also deleterious side effects, e.g. it
changes the microclimate of the crop stand. Our study aimed to observe the differences, which characterise the physical status of crop stands
under the protection of hail nets compared with the stands in open air under various meteorological conditions: high or low temperature, calm
or windy atmosphere and their possible combinations. The results indicated that on hot and calm days the difference may attain 3–4° C. On
cool summer days, the difference was only 1.5 ºC. The hail net influences the relative humidity of the air, which means on ho summer days
often 7-8% differences. Conditions of radiation may also differ conspicuously. Measurements prove the reduced global radiation on sunny
summer days to 70%. This impairs as a rule the development of fruits reducing their quality and also its quantitative traits. Sunburn is, on the
other hand, significantly prevented by shadow. -
Effect of hail protecting nets on the quality of apples
77-80.Views:283Today, successful fruit growing depends largely on the security of production. Among the technological elements of a secure growing system, the use of hail protection nets serves special attention. Components of security are the regularity, conspicuous large yields with excellent quality, which determine the prices and profitability as well (Szabó et al., 2010). In the European Union, most of the apple growing countries produce higher yields by 10-20% than Hungary. The conditions of better yields are partly due to a more favourable ecological milieu, partly to more developed technologies and serious discipline of the operations. Our own competitiveness could be developed first of all in those moments. As a consequence of global climatic changes, excesses of weather, i.e. hail-storms became more frequent. Different methods of protection against hail are developed abroad but also in Hungary. The examination of effects of the hail protection nets compared with the check without nets has been the purpose of our experiments. The growing system was the intensive one with high planting densities. Fruits of the two subsequent years have been compared as grown with and without hail protective nets. It turned out that in one season when shoot growth was stimulated, the shadowing effect of the net increased in addition the growth and at the same time braked the differentiation of flower buds, which exerted negative effects on yield of the next year. Let alone this phenomenon, the quality of fruits was not influenced by the hail protection net.
-
Extreme weather events inWest Hungary
29-32.Views:288Agricultural production is a rather risky activity, as it is largely exposed to extreme weather events. This paper focuses on the frost and hail data in springtime, affecting fruit production in West Hungary. Regarding absolute minimum temperatures in April, significant increase of the standard deviations could be observed. Among the sites examined Nagykanizsa shows the highest risk values. According to our evaluation Nagykanizsa is not recommended to plant sour cherry, sweet cherry and apricot orchards because in some years spring frost will occur. If the plantation is in Zalaegerszeg, Szombathely, Gyôr or Keszthely than usage of frost prevention system is recommended. Siófok is the only area to grow apricot with good result.
-
Work quality assessment of a cherry sorting machine
57-62.Views:370The conditions of the cultivation of marketable cherries are diverse. Choosing the production site on the basis of the climatic conditions, selecting the most appropriate variety taking into account the region and the purpose of the production, utilization of the optimal production method, to ensure the required water and nutrients supply, frost and hail protection techniques, modern technology in crop protection, and professional performance of harvesting and handling, to name just a few of the most important issues. The objective of present study is to determine the qualitative characteristics of the UNITEC cherry sorting machine.
-
Conditions of rentability in the apricot industry of Hungary
127-129.Views:185Total investment costs of an up to date apricot plantation requires about 5000 thousand HUF/ha. Modern
plantations yield under normal conditions 15–20 t/ha with 80% quality for fresh consumption. Consequently, taking the life span of a plantation (15 years), the internal rate of return of 15–17% per year (IRR), that means that the costs of investment will be regained in the 9–10th year, which is considered to be satisfactory. However, weather hazards (frost, hail) may occur at a probability of 20–25%, therefore, maintaining the quality (80% for fresh consumption) and yields (15–20 t/ha) are badly needed to speak about rentability. This level of yields maintains the option of feasibility up to 20–25% losses. -
Integration of terrestrial laser scanning and spectral canopy scanner in horticulture applications
15-18.Views:286One of the most difficult challenge in the everyday practice to describe the canopy growing of fruit trees in an orchard. The photosynthetic activity is the basic of the primer production of plants. The measurement of leaf area and determination of the photosynthetic activity could be occurred with some elaborated methods between experimental conditions. In this article we present such an integrated methodology, which is ideal to determine the geometric and spectral characteristic of fruit trees between field conditions.We have carried out laser scanning technology to investigate the geometric-topological characteristics and parallel the active infra-red sensor to collect spectral data about an apple orchard. The surveys were worked out in an intensive apple orchard with drip irrigation system, protected by hail net in Study and Regional Research Farm of the University of Debrecen near Pallag. This study shows the filtering and interpretation methods of created data. The produced high accuracy data can be directly used in the precision horticulture. It could serve as a guiding data to implementation a future “virtual horticulture”. Higher spatial and temporal resolution could help for a better recognition of water balance of orchards.