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16-kanałowy moduł LED do systemu wspomagającego rozwój roślin sterowany za pomocą Raspberry PI

Feldzensztajn Mateusz, Pluciński Jerzy, Siedlecki Sebastian, Mazikowski Adam

Przegląd Elektrotechniczny

2023

R. 99, nr 7

215--219

Obecnie dużym zainteresowaniem cieszą się badania wpływu światła na rośliny. Opracowywane są nowe rozkłady widma światła, które wpływają na poprawę zarówno ilości plonów i jakości dokonywanych zbiorów. W celu uproszczenia wprowadzania zmian widma w procesach badawczych oraz w celu przyspieszenia i zrównoleglenia badań w tym zakresie został opracowany niedrogi programowalny moduł LED pozwalający sterować 16 niezależnymi stałoprądowymi kanałami. Niska cena proponowanego rozwiązania oraz jeden sterownik obsługujący do 12 modułów LED może przyczynić się do bardziej efektywnych poszukiwań optymalnego widma dla poszczególnych gatunków roślin.

Nowadays, research on the horticulture light is receiving a lot of interest. Scientists are looking for the best light spectra and are developing new spectra to improve the quantity and quality of crops. To simplify the introduction of spectrum changes in research processes and to accelerate research in this area, an inexpensive programmable 16 channels LED module has been developed. The low price of the described solution and one controller supporting up to 12 modules may help in a more effective search for the optimal spectrum for individual plant species.

Seedling survival and dynamics of upper timberline in Central Apennines

Catorci A., Scapin W., Tardella F., Vitanzi A.

Polish Journal of Ecology

2012

Vol. 60, nr 1

79-94

Despite several studies on the timberline dynamics in Europe were carried out in the last decades, very few papers refer to mountain areas where the timberline is composed of broadleaved trees, and no research was conducted on the dynamics of Apennine beech timberline in relation to seedling survival. The research aim was to analyse the beech wood timberline dynamics in the central Apennines, with reference to seedling survival. Furthermore, factors affecting seedling survival were identified. To assess the forest ecotone dynamics, vegetation layer cover, rock fragment cover and information about forest management and krummholz occurrence were collected in sampling plots placed over 1,600 m a.s.l., on north-facing slopes. The beech seedlings occurring in Brachypodium genuense-dominated stands above the timberline were counted and monitored along two growing seasons. Soil temperature, soil moisture, and photosynthetically active radiation available for seedlings (PHAR) in grasslands above timberline were measured. The research outputs indicate that timberline is not a natural boundary and that there is no evidence of its extension upwards. The greatest number of beech seedlings was recorded in late spring. The one-year mortality rate ranged from 71 to 100%. None of the seedlings still alive in the early autumn of the first year were recorded in the following spring. The competitive exclusion by Brachypodium genuense individuals, which limit the incident PHAR, and the low soil moisture during summer, were identified as the main factors that account for the high mortality of seedlings and affect beech regeneration above timberline. The effect of competition is probably intensified by the lack of pioneer shrubs which could otherwise serve as nurse plants for beech seedlings and protect them from browsing by wild ungulates. Thus, both the current and the past land use may be considered as driving forces in timberline dynamics. Probably, also the trend of global warming, that in the Mediterranean and sub-Mediterranean climatic context would determine the increase of summer drought stress, could worsen the effect of competitive exclusion of beech seedlings, so that it can be hypothesized that the expansion upwards of the upper timberline in the Apennines could be totally blocked.