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Summary

A prototype for pest development stages forecasting is developed in Kazakhstan exploiting data from the geoinformation technologies and using codling moth as a model pest in apples. The basic methodology involved operational thermal map retrieving based on MODIS land surface temperature products and weather stations data, their recalculation into accumulated degree days maps and then into maps of the phases of the codling moth population dynamics. The validation of the predicted dates of the development stages according to the in-situ data gathered in the apple orchards showed a good predictivity of the forecast maps. Predictivity of the prototype can be improved by using daily satellite sensor datasets and their calibration with data received from a network of weather stations installed in the orchards.

Summary

Three-year studies on the influence of temperature on vegetative growth and growth of broccoli heads (Brassica oleracea var. italica cv. Fiesta) were carried out at the Experimental Station “Marcelin” of Poznań University of Life Sciences in Poland. The relationship between temperature sum day-degree, number and area of leaves as well as head diameter was estimated. Likewise relationship between number and area of leaves and head diameter was established. The correlations were described using linear, curvilinear and segment linear regression. The relationship between temperature sum day-degree and number of leaves was linear, whereas the correlation between temperature and area of leaves and head diameter was curves function. On the basis of segment linear regression it was found that in the period when slow growth of heads was observed (the size of up to about 1.5 cm), the area of leaves increased the fastest. It occurred between the 24th and 27th day after planting. The fastest growth of broccoli heads was noted, when the plant had about 18 leaves and area 4900 cm2. In the period of rapid head growth, the increase of sum temperature of 100 day-degree resulted in head diameter increase by 3.5 cm.

Abstract

The aim of this study was to determine the dynamics of the process of a course of ice creation phenomena in two small water bodies located in the Silesian Upland. The studies and observations of ice formation on the water bodies were conducted during the period 10th November 2011 to 23rd March 2012. The following parameters were determined each day: degree of ice coverage on each water body, thickness and ice structure and thickness of snow cover on each water body. From the studies it results that a course of the ice formation of both water bodies was almost identical. The same maximum ice thickness was recorded in both cases. It was 36 cm in that season, with slight differences in average thickness. The course of particular phases of ice formation in different water regions was also very similar. The number of days with the ice phenomena and the number of days from the beginning to the end of the ice phenomena were identical in both cases, being 96 and 131 days, respectively. The slight differences over several days were recorded in the case of: number of days with shore ice (lb), number of days with partial ice cover (lcz), number of days with an incomplete ice cover (lnp), number of breaks in the ice cover (B). Additionally, with daily measurements of ice cover thickness the relationships between the course of the average daily air temperature from the meteorological station of Faculty of Earth Sciences of University of Silesia and the daily changes in the ice thickness in the water regions in question were determined by using Spearman’s correlation coefficient. In both cases the relationships were strong and they were r= −0,84(p<0,001) for the Amendy water body and r= −0,87 (p<0,001) for the Żabie Doły S water body. The maximum and average ice thickness, duration of the ice phenomena and ice cover and the obtained correlation coefficients between the air temperature and the changes in the ice thickness show that the water bodies in question are characterized by a quasi-natural ice regime.