Pollen analysis is one of the best and possible approaches for the quantitative reconstruction of paleobotany and paleoclimate,and discrimination of human activities.In this paper,we reveal the characteristics of poll...Pollen analysis is one of the best and possible approaches for the quantitative reconstruction of paleobotany and paleoclimate,and discrimination of human activities.In this paper,we reveal the characteristics of pollen assemblages in different agricultural units and their spatial distribution of major pollen taxa in the Anyang area where the human influences are serious,so as to get more information about climate change and human activities from pollen records.The pollen assemblages of total 122 surface soil samples from different agricultural units (farm lands,vegetable plots,wastelands,cape-lands,woodlands,etc.) indicate that herbaceous pollen dominates the pollen assemblages with an average of 73%,mainly from Poaceae,Artemisia,Chenopodiaceae and Cruciferae;arboreal pollen percentages reach 18%,mainly from Pinus and Ulmus;shrub pollen and fern spores have very low percentages.In general,pollen assemblages are consistent with vegetation composition,though some differences also exist in different agricultural units.In farmlands and vegetable lands,Poaceae pollen has the highest percentages (averaging 27%) compared to other agricultural units with dominant corn or wheat pollen,while in wastelands and woodlands,arboreal and Artemisia pollen percentages have higher values (averaging 20% and 19% respectively).Cruciferae has the highest pollen percentages (70%) in rape-lands.Both pollen assemblages and PCoA can generally identify the vegetable plots,farmlands,woodlands,wastelands,and rape-lands.Pinus and Artemisia pollens mainly appear in the western part of Anyang,which is consistent with the parent plants;Poaceae pollen mainly exist in the eastern part with more farmlands;Chenopodiaceae pollen mainly appear in the urban areas and near major roads where human influences are stronger,Cruciferae pollen can mainly be found in the urban area and in the northwest part of Anyang where more vegetables are planted.展开更多
Twenty five surface (0—20 cm) soil samples were collected from different locations in Egypt representing non polluted, moderately and highly polluted soils. The aim of this study was to evaluate total Co content ...Twenty five surface (0—20 cm) soil samples were collected from different locations in Egypt representing non polluted, moderately and highly polluted soils. The aim of this study was to evaluate total Co content in alluvial soils of Delta in Egypt using the delayed neturen activation analysis technique (DNAA). The two prominent gamma ray lines at 1173 2 and 1332 5 keV was efficiently used for 60 Co determination. Co content in non polluted soil samples ranged between 13 12 to 23 20 ppm Co with an average of 18 16±4.38 ppm. Cobalt content in moderately polluted soils ranged between 26 5 to 30 00 ppm with an average of 28 3±1.3 ppm. The highest Co levels (ranged from 36 to 64 69 ppm with an average of 51 9±9.5); were observed in soil samples collected from, either highly polluted agricultural soils due to prolonged irrigation with industrial wastewater or surface soil samples from industrial sites.展开更多
基金supported by the National Key Natural Science Foundation of China (Grant No.40730103)National Natural Science Foundation of China (Grant Nos.40571166 and 40672107)+3 种基金Master Foundation of National Education Ministry (Grant No.20050094004)Hebei Natural Science Foundation (Grant Nos.D2008000186 and D2009000300)Hebei Special Foundation for Ph.D (Grant No.06547006-3)Hebei Foundation for Key Subject Construction of University and Social Sciences and Humanities Research Council of Canada (Grant No.410-2006-2020)
文摘Pollen analysis is one of the best and possible approaches for the quantitative reconstruction of paleobotany and paleoclimate,and discrimination of human activities.In this paper,we reveal the characteristics of pollen assemblages in different agricultural units and their spatial distribution of major pollen taxa in the Anyang area where the human influences are serious,so as to get more information about climate change and human activities from pollen records.The pollen assemblages of total 122 surface soil samples from different agricultural units (farm lands,vegetable plots,wastelands,cape-lands,woodlands,etc.) indicate that herbaceous pollen dominates the pollen assemblages with an average of 73%,mainly from Poaceae,Artemisia,Chenopodiaceae and Cruciferae;arboreal pollen percentages reach 18%,mainly from Pinus and Ulmus;shrub pollen and fern spores have very low percentages.In general,pollen assemblages are consistent with vegetation composition,though some differences also exist in different agricultural units.In farmlands and vegetable lands,Poaceae pollen has the highest percentages (averaging 27%) compared to other agricultural units with dominant corn or wheat pollen,while in wastelands and woodlands,arboreal and Artemisia pollen percentages have higher values (averaging 20% and 19% respectively).Cruciferae has the highest pollen percentages (70%) in rape-lands.Both pollen assemblages and PCoA can generally identify the vegetable plots,farmlands,woodlands,wastelands,and rape-lands.Pinus and Artemisia pollens mainly appear in the western part of Anyang,which is consistent with the parent plants;Poaceae pollen mainly exist in the eastern part with more farmlands;Chenopodiaceae pollen mainly appear in the urban areas and near major roads where human influences are stronger,Cruciferae pollen can mainly be found in the urban area and in the northwest part of Anyang where more vegetables are planted.
文摘Twenty five surface (0—20 cm) soil samples were collected from different locations in Egypt representing non polluted, moderately and highly polluted soils. The aim of this study was to evaluate total Co content in alluvial soils of Delta in Egypt using the delayed neturen activation analysis technique (DNAA). The two prominent gamma ray lines at 1173 2 and 1332 5 keV was efficiently used for 60 Co determination. Co content in non polluted soil samples ranged between 13 12 to 23 20 ppm Co with an average of 18 16±4.38 ppm. Cobalt content in moderately polluted soils ranged between 26 5 to 30 00 ppm with an average of 28 3±1.3 ppm. The highest Co levels (ranged from 36 to 64 69 ppm with an average of 51 9±9.5); were observed in soil samples collected from, either highly polluted agricultural soils due to prolonged irrigation with industrial wastewater or surface soil samples from industrial sites.
