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PL
Jednym z objawów zamierania drzewostanów dębowych w Europie jest wysoka defoliacja obserwowana u drzew o słabej zdrowotności. Na potrzeby corocznego monitoringu dotkniętych patogenem Phytophtora powierzchni badawczych projektu HESOFF w Zakładzie Teledetekcji Instytutu Lotnictwa podjęto próbę wytworzenia metodyki oceny defoliacji za pomocą lotniczych zdjęć wielospektralnych. W tym celu w lipcu 2015 r. za pomocą Platformy Wielosensorowej QUERCUS.6 wykonano zdjęcia lotnicze badanego kompleksu leśnego (zakres 0,46–0,82 μm). Na podstawie zdjęć wykonano pomiar reflektancji dla każdego z badanych dębów oraz porównano pozyskane w ten sposób dane radiometryczne z ocenionym metodą tradycyjną poziomem defoliacji. Na podstawie uzyskanych korelacji wykazano, że pomiar defoliacji jest możliwy przy zastosowaniu kanałów optycznych: 0,46–0,52 μm oraz 0,67–0,82 μm. Wykazano ponadto, że do poprawnego pomiaru defoliacji zaproponowaną w tym artykule metodą, konieczne jest uwzględnienie typu podszytu, który ma decydujący wpływ na obserwowaną reflektancję.
EN
One of the symptoms of dieback of oak stands in Europe is high defoliation, observed in trees with poor health. For the purposes of annual monitoring (in research project HESOFF) of the research area affected by the pathogen Phytophthora, in the Remote Sensing Department of Institute of Aviation was made attempt to develop a proper methodology for defoliation evaluation with multispectral aerial images use. For this purpose in July 2015 with the use of the Multisensory Platform QUERCUS.6 aerial photos of the test forest complex were made (range: 0.46–0.82 μm). Based on the photos, reflectance measurements for each of investigated oaks were made and acquired parameters have been compared with defoliation level obtained by conventional methods. Based on these correlation has been demonstrated that defoliation measurement is possible with use of optical channels: 0.46–0.52 μm and 0.67–0.82 μm. It was also shown that for correct defoliation measurement with proposed in this article methodology it is necessary to take into account the type of underbrush, which has a decisive influence on the observed reflectance.
EN
Light environments can have a considerable influence on how plants respond to defoliation through influencing the biomass allocation patterns and internal C/N ratio. Seedlings of Lolium perenne, a common perennial grass species, were grown for eight weeks under three different light environments (natural light, red light and shading) and two different defoliation treatments (no defoliation versus 50% aboveground biomass removal). This study was conducted to examine (1) the effects of light regimes and defoliation on biomass accumulation, biomass allocation and internal C/N ratio status in plants; (2) how the light regimes influence the pattern of compensatory growth after defoliation; and (3) the relationship between compensatory growth and the internal C/N ratio status. We found that red light altered the shoot-to-root allometry, enhanced the leaf C concentrations and induced N deficiency. By contrast, the leaf N concentrations of L. perenne were greater during shading treatment, which simultaneously enhanced shoot growth and stopped root growth. Under defoliation, red light increased shoot growth, not at the expense of root growth, which was not the same as in natural light and shading treatment. Moreover, regardless of the unclipped (no defoliation) and defoliation conditions, the L. perenne biomass partitioning between roots and shoots was significantly correlated with the leaf N concentrations and C/N ratio, indicating that allometric biomass allocation can be largely modulated by signals related to the C and N status of the plants. These results demonstrated that the leaf C and N status would be an appropriate indicator of compensatory growth after defoliation.
EN
The European beech is a major component of central European forests, and the eastern limit of its range lies in Poland. However, the Holocene migration of the beech is not yet finished, especially in NE Poland, so the northern distribution of the beech continues to change. The main goal of this study was to determine if the beech will reach its northern limit in the future. The investigation was carried out in 18 beech stands in Poland. To study the status of the health of the trees, circular plots were established in grids of different sizes. The basal beech stand area ranged from 3.7 m2 ha-1 to 31.2 m2 ha-1. The density of trees exceeded a hundred trees per hectare in most of the plots (61%), and the average degree of defoliation was not greater than 60% in all of the investigated stands. Environmental conditions influenced defoliation of beech trees (Fisher's test, F = 4.0204; P <0.0001). The vitality of the beech trees varied between stands (Kruskal-Walis test, H = 139.7433, P <0.0001) and was rather good in 56% of the study plots. Seedlings and saplings were observed in all of the investigated stands, and they covered from 5 to 39% and 21 to 80% of the study plots, respectively. Spontaneous beech regeneration was widespread and differed from stand to stand as well as within stands in all of the study plots. The number of tall seedlings in most of the study plots (56%) was greater than 10,000 individuals per hectare. The factors limiting beech regeneration were stand density and herb cover, and the number of beech seed trees influenced the quantity of small seedlings. Beech tree density positively influenced the number of small seedlings, and the strength of the correlation was moderate and statistically significant (Pearson correlation, r = 0.349). Beech tree density influenced the vitality of tall and small saplings (Pearson's correlations, r = 0.673 and r = 0.361, respectively). The spontaneous regeneration and strong vitality of seedlings and saplings suggests that beech can create stable stands in the future and that it is an expansive tree species both within its continuous range and at the limit of its distribution. It is quite possible that beech will reach its north-eastern limit in Poland in the future.
EN
The research problem of the paper concerned verification whether applicable or known methods of post-harvesting evaluation of the roots of sugar beet may be applied to the assessment of the quality of work of technically varied new machinery for sugar beet harvesting. Tests of machines of varied solutions of working units, in particular a topping unit, were carried out in order to accomplish the objective of the paper. Two self-propelled combine harvesters of Ropa euro-Tiger V8-3 type and Kleine Beetliner Large and two sets for 2-stage harvesting by M.A.C.E (Spain) and Amity (USA) companies were used in the study. Ropa euro-Tiger and Kleine Beetliner Large combine harvesters and M.A.C.E. set were equipped with a beet topper but of a varied topping system, whereas, only a defoliator was used in the set by Amity company. Field research of machines included assessment of the topping quality, losses caused by the broken tip of roots and damages of the lateral surface of roots. Research assumptions were assumed according to the method of the International Institute for Beet Research (I.I.R.B.). Moreover, assessment of the topping quality with the method of the Netherlands Institute of Sugar Beet Research (IRS) and the Institute of Agricultural Engineering of the Bonn University was carried out. Assessment of roots after defoliation was carried out based on the Roller's classification (2010). Based on the research results and analyses which were carried out, it was proved that the methods of measurement of the quality of beet harvesting machines operation are not fully useful for assessment of the introduced technical and technological changes. It mainly concerns the assessment of the roots topping. Thus, two modified methods of assessment of the quality of roots topping were suggested. They may be used both for machines equipped with a topping device and a defoliator.
PL
Problem badawczy pracy dotyczył sprawdzenia, czy obowiązujące lub znane metody oceny pozbiorowej jakości korzeni buraka cukrowego można stosować do oceny jakości pracy zróżnicowanych technicznie nowych maszyn do zbioru buraków cukrowych. Dla zrealizowania celu pracy przeprowadzono badania maszyn o zróżnicowanych rozwiązaniach zespołów roboczych, a w szczególności zespołu ogławiającego. Do badań wyznaczono dwa kombajny samojezdne typu Ropa euro-Tiger V8-3 i Kleine Beetliner Large oraz dwa zestawy do zbioru 2-etapowego firm M.A.C.E. (Hiszpania) i Amity (USA). Kombajny Ropa euro-Tiger i Kleine Beetliner Large oraz zestaw M.A.C.E. były wyposażone w ogławiacz, ale o różnym rozwiązaniu dogławiacza, natomiast w zestawie firmy Amity zastosowano wyłącznie defoliator. Badania polowe maszyn obejmowały ocenę jakości ogłowienia, strat spowodowanych obłamanym końcem korzeni oraz uszkodzeń powierzchni bocznej korzeni. Założenia badawcze przyjęto zgodnie z metodą Międzynarodowego Instytutu Buraka Cukrowego (I.I.R.B.). Wykonano również ocenę jakości ogłowienia metodą Holenderskiego Instytut Buraka Cukrowego (IRS) oraz Instytutu Inżynierii Rolniczej Uniwersytetu w Bonn. Ocenę korzeni po defoliacji przeprowadzono na podstawie klasyfikacji Rollera (2010). Na podstawie wyników badań i przeprowadzonych analiz wykazano, że stosowane obecnie metody pomiaru jakości pracy maszyn do zbioru buraków nie są w pełni przydatne do oceny wprowadzanych zmian technicznych i technologicznych. Dotyczy to przede wszystkim oceny ogłowienia korzeni. Dlatego zaproponowano dwie zmodyfikowane metody oceny jakości ogłowienia korzeni, które można zastosować zarówno do maszyn wyposażonych w ogławiacz, jak i defoliator.
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