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1
Artykuł dostępny w postaci pełnego tekstu - kliknij by otworzyć plik
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Research of the biodegradability of degradable/biodegradable plastic material in various types of environments

100%
Adamcova D., Radziemska M., Fronczyk J., Zloch J., Vaverkova M. D.
Przegląd Naukowy. Inżynieria i Kształtowanie Środowiska
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2017
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tom 26
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nr 1[75]
Research of the biodegradability of degradable/biodegradable plastic material in various types of environments. Research was carried out in order to assess biodegradability of degradable/biodegradable materials made of HDPE and mixed with totally degradable plastic additive (TDPA additive) or made of polyethylene (PE) with the addition of pro-oxidant additive (d2w additive), advertised as 100% degradable or certified as compostable within various types of environments. Research conditions were: (i) controlled composting environment – laboratory-scale, (ii) real composting conditions – domestic compost bin, (iii) real composting conditions – industrial composting plant and (iv) landfill conditions. The results demonstrate that the materials made of HDPE and mixed with totally degradable plastic additive (TDPA additive) or made of polyethylene (PE) with the addition of pro- -oxidant additive (d2w additive) or advertised as 100% degradable did not biodegrade in any of the above-described conditions and remained completely intact at the end of the tests. Biodegradation of the certified compostable plastic bags proceeded very well in laboratory-scale conditions and in real composting conditions – industrial composting plant, however, these materials did not biodegrade in real composting conditions – domestic compost bin and landfill conditions.
2

Species distribution models to estimate the deforested area of Picea crassifolia in arid region recently protected: Qilian Mts. National Natural Reserve (China)

84%
Xu Z., Zhao C., Feng Z.
Polish Journal of Ecology
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2012
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tom 60
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nr 3
The earth is now facing the land degradation due to human disturbance, natural habitats were converted to rural and agricultural areas in order to fulfill the increasing demand of human population. The deforestation of Picea crassifolia (Qinghai spruce) forest at Qilian Mts is an example of such disturbance. P. crassifolia is an ecologically and hydrologically important plant species in the northwestern arid area of China. However, the forests have been intensively and extensively deforested. In order to restore the human-disturbed ecosystems, the spatial distribution of P. crassifolia needs to be delineated. This study employed Genetic Algorithm for Rule-set Prediction model (GARP) and Maximum entropy model (Maxent) and four environmental variables (mean temperature of the warmest quarter, precipitation of the wettest quarter, annual solar radiation, topographic wetness index) to predict the potential distribution of P. crassifolia in Qilian Mts. Genetic Algorithm for Rule-set Prediction model (GARP) produces a model of species niches in geographic space based on heterogeneous rule-sets. Maximum entropy model (Maxent) focuses on fitting a probability distribution for occurrence based on the idea that the best explanation to unknown phenomena will maximize the entropy of the probability distribution, subject to the appropriate constraints. The environmental variables were spatially interpolated throughout the entire study area. We used sensitivity-specificity sum maximum approach to select the threshold value. The projected niche space for the mean temperature of the warmest quarter is between 8.5 and 18.1°C; the space for the precipitation of the wettest quarter is between 149 and 245 mm; the space for annual solar radiation is 118–1100×103 wh m–2 and the space for topographic wetness index is between –0.4 and 5.1. The results show that both GARP and Maxent’s models produce acceptable predictions, but the overall comparison shows that GARP prediction is better than Maxent’s; the comparison between the observed distribution and the predicted distribution suggests that 61% (2869 km2) of P. crassifolia forests have been deforested.
3
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Spatio-temporal variability in the Brazil-Malvinas Confluence Zone (BMCZ), based on spectroradiometric MODIS-AQUA chlorophyll-a observations

84%
Telesca L., Pierini J. O., Lovallo M., Santamaria-del-Angel E.
Oceanologia
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2018
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tom 60
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nr 1
The Brazil–Malvinas Confluence Zone (BMCZ) is characterized by high environmental variation, which could be reflected in several optical types of water, from one containing only phytoplankton and sea water to other optically more complex. In this paper, we analyze the spatio-temporal variability of the Chlorophyll-a detected by the ocean color sensor (CHLAsat) in BMCZ in order to understand its environmental variability. We use the MODIS-Aqua CHLAsat monthly composites imagery from 2002 to 2015, and applied two statistical methods: the correlogram-based robust periodogram to identify, over a broad spectrum of temporal, the most significant periodicities, and the pixel gradient distribution to study the spatial-temporal gradients within the BMCZ and variations over the continental shelf and coastal waters. Our results point out to the predominance of the annual cycle over most of the investigated area, although an area from latitude 37°S in direction NE, alongshore of Uruguay to Brazil, evidences interannual periodicities, possibly related to variations in the discharge of the Rio de la Plata associated with the El Niño phenomena. The ocean color spectroradiometric signature in terms of pixel gradient presents a relatively high variability (∼0.0 to 0.65 mg m−3); in particular the high values of the pixel gradient correspond to saline front of the estuarine system of Rio de la Plata, and to the strip of the platform that extends along the isobaths of 80 m (coast of Uruguay), especially in the center and south of the study area.
4

Effects of environmental variation and spatial distance on the beta diversity of woody plant functional groups in a tropical forest

84%
Zhang Z., Zang R., Wang L., Wang G., Zhang J.
Polish Journal of Ecology
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2012
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tom 60
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nr 3
Tropical forests are among the most complex ecosystems on Earth. The high alpha-diversity of tropical forests has been amply documented, however, beta diversity, equally important for us to understand the mechanism of biodiversity maintenance, has seldom been studied. The main current hypotheses about the origin of beta diversity are as follows: (1) species composition is uniform over large areas; (2) species composition fluctuates in a random, auto-correlated way emphasizing spatially limited dispersal; (3) species composition is related to environmental conditions. Testing these hypotheses is important to understand ecosystem function and to manage ecosystems effectively. In this study, we quantified the relative influence of environmental variation and spatial distance on the beta diversity of woody plant functional groups in a tropical forest of Hainan Island, China. Floristic and environmental data were collected from 135 grid-sample plots. We classified woody plant functional groups based on frequency, growth forms and successional status, respectively. To see whether environmental variation and spatial distance influence beta diversity, the simple and partial Mantel tests, in conjunction with linear and spline regression models were performed. The results showed that environmental heterogeneity and spatial distance were the primary determinants of pair-wise species composition differences between plots in the study area. Common, tree and climax species were more sensitive than the others to changes in environmental heterogeneity and spatial distance. Except for rare, pioneer and shrub species, the others had apparently negative relationship between spatial distance and similarity. The distance decay of similarity was determined by joint influences of spatial distance and spatially-structured environmental variables. Spatial distance had the clearest effect on beta diversity at distances <15 km and with the increase in spatial distance, beta diversity was gradually controlled by environmental heterogeneity. This study provides further support for neutral theory and environmental control hypothesis as opposed to uniformly distributed hypothesis.
5

Seasonal variation in the feeding habits of riparian mustelids in river valleys of NE Belarus

67%
Sidirovich V. E.
Acta Theriologica
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2000
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tom 45
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nr 2
In 1986-1997, diet composition of the native riparian mustelids: the otter Lutra lutra (Linnaeus, 1758), the European mink Mustela lutreola (Linnaeus, 1761), the polecat M. putorius (Linnaeus, 1758), and the naturalized one, the American mink M. uison (Schreber, 1777) was studied in relation to seasonal changes of the habitats (the Lovat river, NE Belarus). Amphibians, fish, crayfish, small mammals, and birds appeared the essential prey resources supporting the guild of riparian mustelids. In the river valleys, the two mink species and polecat were characterized by opportunistic feeding habits, whereas the otters specialised on fish. In spring and autumn, frogs were important prey to all mustelids studied. The trophic niches of the two mink species were wider than those of the otter and the polecat. In the seasonally changing environ­mental conditions, the American mink appeared a more opportunistic predator than the European mink. Food niches of the three native mustelids overlapped notably less with each other (Pianka's a from 0.24 to 0.70) than with the American mink (a from 0.60 to 0.89). The obtained data suggest that in river valley habitats the naturalized American mink may be a strong competitor for prey with the native riparian mustelids, especially the European mink and the polecat.
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