The study investigates the germination of selected leguminous tree species (LTS) native to the forest ecosystem and oil producing areas of Nigeria. Germination experiments of 250 seeds from each of the selected member...The study investigates the germination of selected leguminous tree species (LTS) native to the forest ecosystem and oil producing areas of Nigeria. Germination experiments of 250 seeds from each of the selected members of the Fabaceae family: Bauhinia monandra (Kurz), Delonix regia (Boj. ex Hook.) Raf. and Tetrapleura tetraptera (Schum. & Thonn.) Taubert were conducted in petri dishes double-layered with Whatman No. 1 filter papers for 10 days and moistened with varying concentrations of crude oil contaminated soil water extracts (0, 25, 50, 75 and 100 ml), with a view to determining the ability of these plants to germinate and establish in soil polluted with crude oil. The mean percentage germination of each tree species was thus determined. All the LTS germinated, but germination was concentration dependent, as percentage germination decreased with increased oil concentrations. Evaluation of the initial growth responses and tolerances of these LTS in oil-polluted soil may provide useful information about the potential of these plant species for phytoremediation.展开更多
Soil erosion and land degradation are global problems and pose major issues in many countries. Both soil erosion and mass movement are two forms of land degradation and humans play important roles in these geomorpholo...Soil erosion and land degradation are global problems and pose major issues in many countries. Both soil erosion and mass movement are two forms of land degradation and humans play important roles in these geomorphological processes. This paper reviews slope processes associated with mass movement and soil erosion and contributory factors, including physical and human agents. Acting together, these cause diverse geomorphological features. Slope processes are illustrated by reference to case studies from Brazil and UK. The causes and impacts of erosion are discussed, along with appropriate remedial bioengineering methods and the potential of the measures to prevent these types of environmental degradation. Although there are several agents of erosion, water is the most important one. Cultivation can promote soil erosion, due to ploughing and harvesting, which moves soil down slopes. Soil erosion and mass movement data would inform the viability of soil conservation practices. Integrated management of drainage basins offers a Dromising way forward for effective soil conservation and soil remedial bioengineering in Brazil and UK.展开更多
文摘The study investigates the germination of selected leguminous tree species (LTS) native to the forest ecosystem and oil producing areas of Nigeria. Germination experiments of 250 seeds from each of the selected members of the Fabaceae family: Bauhinia monandra (Kurz), Delonix regia (Boj. ex Hook.) Raf. and Tetrapleura tetraptera (Schum. & Thonn.) Taubert were conducted in petri dishes double-layered with Whatman No. 1 filter papers for 10 days and moistened with varying concentrations of crude oil contaminated soil water extracts (0, 25, 50, 75 and 100 ml), with a view to determining the ability of these plants to germinate and establish in soil polluted with crude oil. The mean percentage germination of each tree species was thus determined. All the LTS germinated, but germination was concentration dependent, as percentage germination decreased with increased oil concentrations. Evaluation of the initial growth responses and tolerances of these LTS in oil-polluted soil may provide useful information about the potential of these plant species for phytoremediation.
基金the financial support of the Brazilian Research Council(CNPq)
文摘Soil erosion and land degradation are global problems and pose major issues in many countries. Both soil erosion and mass movement are two forms of land degradation and humans play important roles in these geomorphological processes. This paper reviews slope processes associated with mass movement and soil erosion and contributory factors, including physical and human agents. Acting together, these cause diverse geomorphological features. Slope processes are illustrated by reference to case studies from Brazil and UK. The causes and impacts of erosion are discussed, along with appropriate remedial bioengineering methods and the potential of the measures to prevent these types of environmental degradation. Although there are several agents of erosion, water is the most important one. Cultivation can promote soil erosion, due to ploughing and harvesting, which moves soil down slopes. Soil erosion and mass movement data would inform the viability of soil conservation practices. Integrated management of drainage basins offers a Dromising way forward for effective soil conservation and soil remedial bioengineering in Brazil and UK.
