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  • Botanical Survey of a Seminatural Saline Meadow
    38-44
    Views:
    91

    We made a botanical survey of a seminatural meadow situated in the vicinity of Hajdúnánás-Tedej in Hungary, using traditional phytocenological methods. The habitat, based on its soil-, and botanical characteristics, can be classified into the category of saline meadows. One of the landscape ecological values of this area is its mosaic-like structure and, as a consequence, this habitat can be divided into six characteristic associations with blurry borderlines and characteristic overlaps. Because of its rare plant species and species richness this area can be considered to be a valuable „seed bank” and a „stepping stone” in the ecological network among the larger, intensively cultivated fields. The area can be evaluated as moderately recovered, the natural species are dominant, but there are few disturbance tolerant species. Except for the two saline associations, the high grass associations, which make up about two-thirds of the habitat, are cut once a year; therefore, the agricultural utilisation of the area and its prevention against weediness are being assured at the same time.

  • Usage of Different Spectral Bands in Agricultural Environmental Protection
    123-126
    Views:
    97

    Hyper and multispectral imaging systems are widely used in agricultural and environmental protection. Remote sensing techniques are suitable for evaluating environmental protection hazarsd, as well as for agriculture resource exploration. In our research we compared aerial hyper and multispectral images, as well as multispectral digital camera images with the background data from the test site. Hyperspectral records were obtained using a new 80-channeled aerial spectrometer (Digital Airborne Imaging Spectrometer /DAIS 7915/. We have chosen two farms where intensive crop cultivation takes place, as test sites, so soil degradation and spreading of weeds can be intensive as a result of land use and irrigation. We took additional images of air and ground with a TETRACAM ADC wide band multispectral camera, which can sense blue, green and near infrared bands. We had detailed GIS database about the test site. Weed and vegetation map of the area in the spring and the summer was made in 2002. For soil salt content analysis, we gathered detailed data frome an 80x100 m area. When analyzing the images, we evaluated image reliability, and the connection between the bands and the soil type, pH and salt content, and weed mapping. In the case of hyperspectral images, our aim was to choose and analyze the appropriate band combinations. With a TETRACAM ADC camera, we made images at different times, and we calculated canopy, NDVI and SAVI indexes. Using the background data mentioned above, the aim of our study was to develop a spectral library, which can be used to analyze the environmental effects of agricultural land use.