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Landscape indices and landuse - tools for landscape menagement

Szabo S., Csorba P., Varga K.

Prace Komisji Krajobrazu Kulturowego

2008

nr 8

7--20

Describing the environment with quantitative data is a new requirement in the environment related sciences which is the consequence of the developing computerbased methods. New requirements with new tools generated quick development in the measuring level: parameters turned to be measurable in several subjects. Landscape ecology as a young science has its own methods from the beginnings, but the quantified landscape geometry indices appeared only in the 1980s. Exploration of the landscape structure made necessary to elaborate those methods which were applicable to characterize the patches, corridors and the matrix of the landscapes. Nowadays we can find several landscape indices to quantify the geometry of landscape elements in patch and landscape level, but they are not used in the practice of the landscape management. It is shown in this paper that these landscape indices what novelty can mean in a sample area of Northern Hungary and what can be the practical side of their the usage. FRAGSTATS software was used to calculate landscape metrics. Principal component analysis was applied to reduce redundancy of indices and, based on the results, some of them was selected. Land use types and microregions were used as dependent variables in a discriminant function analysis. Both of them were identifiable with this method in several cases. Landscapes were clustered based on the characteristics of the landscape indices.

Measuring the Heat of Wetting of Textile Fibres by Reaction Calorimetry

Varga K., Schädel U., Nilsson H., Persson O., Schuster K. C.

Fibres & Textiles in Eastern Europe

2007

Vol. 15, no. 5-6 (64)

59--63

The heat of wetting of regenerated cellulosic fibres (TENCEL®, Viscose and Modal) was investigated by reaction calorimetry in comparison with cotton, polyester and TENCEL® Fabric. Reaction calorimetry is a technique applied for measuring the heat evolved in chemical reactions where very high analytical precision is required. Before the measurements, the fibre samples were dried in an oven at 80 °C for 60 min with a low and constant nitrogen flow to eliminate initial moisture. As final results the amount of heat in Joules per gram fibre is given. The experimental results showed that the highest heat of wetting was measured for man–made cellulosic fibres, middle for cotton, while the lowest heat of wetting was observed for polyester fibres. The heat of wetting depends on the interaction of water with hydroxyl groups in the non–crystalline domains of the fibre. Finally, the results of the heat of wetting obtained by modern reaction calorimetry were compared with results obtained using a self–constructed solution calorimeter, as well as with data reported in earlier studies.

Ciepło zwilżania regenerowanych włókien celulozowych, takich jak TENCEL®, wiskoza i włókna modalne, badano za pomocą kalorymetrii reakcyjnej w porównaniu do bawełny, poliestru i tkaniny TENCEL®. Kalorymetria reakcyjna jest metodą stosowaną do pomiaru ciepła wydzielanego w wynika reakcji chemicznej, kiedy wymagana jest bardzo duża precyzja pomiaru, Przed pomiarami, próbki włókien były suszone w piecu, w temperaturze 80 °C przez 60 minut, przy bardzo małym, stabilnym przepływie azotu, dla wyeliminowania początkowej wilgotności. Jako końcowy wynik przyjmowano ilość ciepła w J/g włókna. Eksperymentalne wyniki pokazały, że najwyższe ciepło zwilżania pomierzono dla sztucznych włókien celulozowych, średnie dla bawełny, podczas gdy najniższe ciepło zwilżania zaobserwowano dla włókien poliestrowych. Ciepło zwilżania zależy od interakcji wody z grupami hydroksylowymi w niekrystalicznych domenach włókien. Pod koniec badań porównano wyniki uzyskane za pomocą nowoczesnego kalorymetru reakcyjnego z wynikami z kalorymetru roztworowego, zbudowanego przez nas oraz danymi literaturowymi.