Impact of human and environmental factors on land cover changes of an oak silvopastoral system     

Kaloudıs  S.  Pantera  Α.  Papadopoulos  Α.  Galanopoulou  S.  Damianidis  Ch. 《Agroforestry Systems》2021,95(5):931-950

Silvopastoral systems integrate the complexity of forestry and forage-livestock management in an economically and ecologically sustainable way. However, these systems have undergone intensive pressure over the past decades caused by changes in land uses, as well as, in local socioeconomic priorities that suppressed traditional practices such as livestock grazing. These changes have caused land cover spatiotemporal diversifications whose effects were investigated in a traditional oak silvopastoral system at western Greece. In order to investigate the effect of human activities over the study area, the spatiotemporal land cover changes in conjunction with human and animal population changes and the environmental factors altitude, soil depth, inclination and rock type were analyzed. Also, forest-crown density changes were examined as a complimentary factor for the investigation of human intervention in the study area. Data about land-cover changes were derived from aerial orthorectified photographs of years 1945 and 2008, complimented by maps of environmental factors. Data digitization was implemented by the use of ArcGis. Based on the data analysis it derives that land cover changes are mainly attributed to direct human intervention. Environmental factors affect the ecosystem in two ways; first by affecting the location, type and intensity of human activities in the area, for example, soil depth determines where land is more productive and so predetermines the location, type and intensity of agricultural activities. Secondly, in the areas without or with minimal human intervention, environmental factors affect directly the land cover in conjunction with natural species necessities and their antagonistic capabilities.

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Anthropogenic Heavy Metal Pollution in the Surficial Sediments of the Keratsini Harbor, Saronikos Gulf, Greece   总被引：1，自引：0，他引：1  

Stavroula Galanopoulou  Andreas Vgenopoulos  Nikolaos Conispoliatis 《Water, air, and soil pollution》2009,202(1-4):121-130

The contents of ten elements [Cd, Pb, W, Zn, Mn, As, Se, Cr, Cu, and organic carbon (C_org)] have been determined in the surficial sediments of Keratsini harbor, Saronikos Gulf, Greece. The contamination of the sediments was assessed on the basis of geoaccumulation index and to corresponding sediment quality guidelines (SQGs) effects range low/effects range median. The results revealed highly elevated Cd, Pb, W, Zn, As, Se, Cr, Cu, and C_org values (Cd, 190–1,763 mg kg^?1; Pb, 521–1,263 mg kg^?1; W, 38–100 mg kg^?1; Zn, 409–6,725 mg kg^?1; Mn, 95–1,101 mg kg^?1; As, not detectable–1,813 mg kg^?1; Se, not detectable–58 mg kg^?1; Cr, 264–860 mg kg^?1; Cu, 195–518 mg kg^?1; and C_org, 0.69–4.41%). The enrichment of metals in the sediments results from the contribution of the central Athens sewage outfall through which the waste of the Attica basin ends up in Keratsini harbor as well as from industrial and ship contaminants.  相似文献   

Methyl jasmonate stimulates aflatoxin B1 biosynthesis by Aspergillus parasiticus.     

S Vergopoulou  D Galanopoulou  P Markaki 《Journal of agricultural and food chemistry》2001,49(7):3494-3498

Aflatoxin B1 (AFB1) is a highly toxic and carcinogenic metabolite produced by certain Aspergillus species on agricultural commodities. One factor promoting the production of aflatoxin is the presence of high levels of fatty acid hydroperoxides often found in plant material under stress. Jasmonic acid (JA) and its methyl ester (MeJA) are derived from linolenic acid, and their biosyntheses involve the production of lipid hydroperoxides. Exposure of aflatoxigenic mold to jasmonates is likely because the mold attacks plant material and possibly initiates the production of jasmonates. In this study the effect of MeJA on the growth of Aspergillus parasiticus and AFB1 biosynthesis is reported. MeJA, at a final concentration of 10(-4) M in yeast extract sucrose medium, did not have any apparent effect on mycelial growth during the 16 days of observation but did increase significantly the levels of AFB1 after the seventh day of growth. After the ninth day, AFB1 production was decreased in contrast to the control cultures, where the production was constantly increasing. AFB1 determination was performed by immunoaffinity and HPLC after derivatization to AFB2a.  相似文献   

Evaluation of three cultivation practices for early cotton establishment and improving crop profitability     

Theodoros D. Stathakos  Theofanis A. Gemtos  Constantinos A. Tsatsarelis  Stella Galanopoulou   《Soil & Tillage Research》2006,87(2):135-145

Cultivation practices permitting earlier sowing of cotton (Gossypium hirsutum L.) in Greece are required to maximize yields and facilitate harvesting. An experiment was conducted for 2 years in Central Greece to evaluate two alternative systems. The experiment was carried out in a Vertic Cambisol and a Typic Regosol field. Cultivation practices tested were: (1) conventional tillage (CT) and sowing in a flat field, (2) ridge tillage (RT), using autumn ridging and (3) sowing in a flat field under clear plastic film (PF). Early and normal sowings were compared. The effects of the treatment on the crop establishment, growth and yield, as well as on the soil physical properties, were studied. Performance evaluation of the machinery was carried out. The cost of cultivation practices was estimated. Results of soil physical properties were similar for both years. Soil water contents from sowing to plastic removal in 2000 were 14.2, 13.5 and 18.0 g/100 g and temperatures for the same period at 0.04 m depth were 17.7, 18.1 and 19.8 °C for CT, RT and PF, respectively. PF resulted in higher emergence and higher plants with smaller roots. Average yields of seed-cotton in early sowing were 4936, 4591 and 4033 kg/ha for PF, RT and CT, respectively. In late sowing, yields in RT and in CT did not differ significantly. Ridge tillage machinery saved 13.6 kWh/ha (20.9%) compared to conventional tillage machinery. The higher yields under plastic film compensated for the higher cost of the practice at the present prices of seed-cotton.  相似文献