36 research outputs found

    Effect of Tillage and Planting Date on Seasonal Abundance and Diversity of Predacious Ground Beetles in Cotton

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    A 2-year field study was conducted in the southern High Plains region of Texas to evaluate the effect of tillage system and cotton planting date window on seasonal abundance and activity patterns of predacious ground beetles. The experiment was deployed in a split-plot randomized block design with tillage as the main-plot factor and planting date as the subplot factor. There were two levels for each factor. The two tillage systems were conservation tillage (30% or more of the soil surface is covered with crop residue) and conventional tillage. The two cotton planting date window treatments were early May (normal planting) and early June (late planting). Five prevailing predacious ground beetles, Cicindela sexguttata F., Calosoma scrutator Drees, Pasimachus spp., Pterostichus spp., and Megacephala Carolina L. (Coleoptera: Carabidae), were monitored using pitfall traps at 2-week intervals from June 2002 to October 2003. The highest total number of ground beetles (6/trap) was observed on 9 July 2003. Cicindela sexguttata was the dominant ground dwelling predacious beetle among the five species. A significant difference between the two tillage systems was observed in the abundances of Pterostichus spp. and C. sexguttata. In 2002. significantly more Pterostichus spp. were recorded from conventional plots (0.27/trap) than were recorded from conservation tillage plots (0.05/trap). Significantly more C. sexguttata were recorded in 2003 from conservation plots (3.77/trap) than were recorded from conventional tillage plots (1.04/trap). There was a significant interaction between year and tillage treatments. However, there was no significant difference in the abundances of M. Carolina and Pasimachus spp. between the two tillage practices in either of the two years. M. Carolina numbers were significantly higher in late-planted cotton compared with those observed in normal-planted cotton. However, planting date window had no significant influence on the activity patterns of the other species. Ground beetle species abundance, diversity, and species richness were significantly higher in conservation tillage plots. This suggests that field conditions arising from the practice of conservation tillage may support higher predacious ground beetle activity than might be observed under field conditions arising from conventional tillage practices

    ICT or I see tea? Modernity, technology and education in Nepal

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    The use of information and communications technology (ICT) for education in developing countries has been a subject of great interest and speculation, with its proponents arguing that ICT improves educational quality, develops critical thinking skills, expands access, increases economic competitiveness and facilitates inclusion in a rapidly expanding global information society. However, few of these claims have been verified from an empirical standpoint, leading to substantial criticism of the push to expand ICT. This article analyses how the global discourse on ICT in education has unfolded in Nepal, concentrating on educational policies on ICT and how these relate to a rather limited domain of practice. It argues that policies on ICT in education reveal an uneasy and fragmented engagement with the global discourse, while in practice its use is often innovative although so limited as to cause little substantive change. However, in both policy and practice the importance of ICT is more due to its power as a symbol of modernity and progress than any utilitarian value
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