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Ioannis Meliadis Panagiotis Platis Apostolos Ainalis Miltiadis Meliadis 《Environmental monitoring and assessment》2010,163(1-4):455-465
Natural ecosystems are renewable resources with special environmental, social, and economical attributes and characteristics. The increasing need of human beings for a better environment results in the use of new technologies that offer many advantages in detecting changes in the ecosystems. Remote sensing tools, technology, and the spatial analysis of the Geographic Information System were used in determining any changes in this study which attempts to classify land cover over a 10-year period. The study area is in Thessaly, central Greece, and has been classified as a Special Protection Area, because of its important wild fauna. The results have shown that current technologies can be used for modeling environmental parameters which improve our knowledge of the attributes, characteristics, situation, trends, and changes of natural ecosystems. The changes over time that have been observed result from the development of the vegetation or to anthropogenic and socioeconomic reasons. Rational range management will be a very comprehensive tool for farmers. This action will have a positive impact on flora in the rangelands. The core strategy is to combine forest, pasture, and livestock so that each component produces usable products. 相似文献
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Miltiadis Hiskakis Epifania Babou Demetres Briassoulis 《Journal of Polymers and the Environment》2011,19(4):887-907
The increased cost associated with the waste removal and disposal of conventional agricultural plastic in contact with the
soil combined with the gradually decreasing cost of the biodegradable plastics allowed the commercialization of biodegradable
mulching films. Since the conventional thin wall or tape drip irrigation system lies under the mulching film and is used for
one season only, it would be desirable to replace it with a biodegradable one. This paper presents the results of a research
work investigating the possibilities and limitations in developing biodegradable drip irrigation thin wall pipes and pipes.
The first ever experimental biodegradable drip irrigation thin wall pipes were produced. Rigid pipes were also produced for
experimental purposes. Manufacturing problems were encountered in the processing of the biodegradable drippers and irrigation
thin wall pipes with the experimental materials due to the complex formulation of the raw materials and the fact that the
machinery used was specifically designed for PE processing. Experimental biodegradable thin wall pipes made of Bioflex with
embedded drippers made of Mater-Bi were produced. The processing problems encountered with the production of thin wall pipes
were surpassed during the experimental production of rigid type irrigation pipes. A biodegradable rigid irrigation pipe made
of a grade of Mater-Bi, with embedded cylindrical drippers made of another grade of Mater-Bi was produced successfully. A
better understanding of the thermal profile of the biodegradable raw materials and the use of processing equipment adapted
to this profile might allow in the future the manufacturing of thin wall drip irrigation pipes for agricultural applications,
and the use of alternative biodegradable materials. 相似文献
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Demetres Briassoulis Epifania Babou Miltiadis Hiskakis 《Journal of Polymers and the Environment》2011,19(2):341-361
The field performance of experimental biodegradable drip irrigation thin wall and regular pipes was investigated through three
sets of full-scale experiments and in the laboratory. These experimental biodegradable drip irrigation systems were produced
through the processing of biodegradable under real soil conditions polymers, Mater-Bi and Bioflex. The mechanical behaviour
of the biodegradable thin wall pipes during the irrigation period was more unstable when compared to the corresponding behaviour
of the rigid pipes. The tensile strength of the Mater-Bi and Bioflex thin wall pipes remained almost constant during the total
exposure time, except from the folding areas. During the first 7–23 days of exposure in the field, the thin wall pipes had
already lost more than the 50% of their initial elongation at break value due to degradation. However, their hydraulic performance
began to decline only after a period of 100–120 days with the simultaneous formation of the first cracks. Likewise, the majority
of the series of biodegradable rigid pipes exhibited a remarkable reduction in their elongation at break values in the transverse
direction within the first 2 weeks. Despite the significant drop of the elongation at break, all biodegradable rigid pipes
generally retained their tensile strength as well as a satisfactory hydraulic performance during almost the whole duration
of their exposure. A few premature leakages in some points adjoining the drippers were observed after 8–10 weeks of exposure. 相似文献
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