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Environmental Pollution now persist in Nigeria especially the oil-rich regions of Delta State. One of these problems is due to gas flaring. Thermal gradient resulting from the gas flared at Kwale/Okpai gas plant is hereby reported. Surface temperature variations with distance from the flare point were investigated for the four cardinal directions. The results show a surface temperature elevation of about 3.7° C above the mean normal daily temperature within a radius of 270 M. Hence the thermal equilibrium has been altered. This increase in temperature has undesirable effect on man and his environment especially on the socio-economic lives and activities of the inhabitants. It is therefore necessary that Government Agencies empowered to monitor environment such as Federal Environmental Protection Agency (FEPA) should embark on adequate remediation activities in order to stop the environmental degradation before enormous and permanent damage is caused. Furthermore, the companies involved in the gas flaring should be made to be concerned with the danger they may be causing the inhabitants in particular and the populace in general.  相似文献   
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Sustainable use and allocation of aquatic resources including water resources require implementation of ecologically appropriate technologies, efficient and relevant to local needs. Despite the numerous international agreements and provisions on transfer of technology, this has not been successfully achieved in developing countries. While reviewing some challenges to technological innovations and developments (TID), this paper analyzes five TID strategic approaches centered on grassroots technology development and provision of localized capacity for sustainable aquatic resources management. Three case studies provide examples of successful implementation of these strategies. Success requires the provision of localized capacity to manage technology through knowledge empowerment in rural communities situated within a framework of clear national priorities for technology development.  相似文献   
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The degree of interdependence and potential for shared coevolutionary history of frugivorous animals and fleshy-fruited plants are contentious topics. Recently, network analyses revealed that mutualistic relationships between fleshy-fruited plants and frugivores are mostly built upon generalized associations. However, little is known about the determinants of network structure, especially from tropical forests where plants' dependence on animal seed dispersal is particularly high. Here, we present an in-depth analysis of specialization and interaction strength in a plant-frugivore network from a Kenyan rain forest. We recorded fruit removal from 33 plant species in different forest strata (canopy, midstory, understory) and habitats (primary and secondary forest) with a standardized sampling design (3447 interactions in 924 observation hours). We classified the 88 frugivore species into guilds according to dietary specialization (14 obligate, 28 partial, 46 opportunistic frugivores) and forest dependence (50 forest species, 38 visitors). Overall, complementary specialization was similar to that in other plant-frugivore networks. However, the plant-frugivore interactions in the canopy stratum were less specialized than in the mid- and understory, whereas primary and secondary forest did not differ. Plant specialization on frugivores decreased with plant height, and obligate and partial frugivores were less specialized than opportunistic frugivores. The overall impact of a frugivore increased with the number of visits and the specialization on specific plants. Moreover, interaction strength of frugivores differed among forest strata. Obligate frugivores foraged in the canopy where fruit resources were abundant, whereas partial and opportunistic frugivores were more common on mid- and understory plants, respectively. We conclude that the vertical stratification of the frugivore community into obligate and opportunistic feeding guilds structures this plant-frugivore network. The canopy stratum comprises stronger links and generalized associations, whereas the lower strata are composed of weaker links and more specialized interactions. Our results suggest that seed-dispersal relationships of plants in lower forest strata are more prone to disruption than those of canopy trees.  相似文献   
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Reclaimed wastewater is an important source of irrigation in semiarid and arid zones. Here we report data on carbamazepine (CBZ) uptake by cucumber plants in hydroponic culture and greenhouse experiments using different soil types irrigated with fresh water or reclaimed wastewater. Data obtained from the hydroponic culture experiments suggest that CBZ is mainly translocated by water mass flow, and thus it is concentrated and accumulated to the largest extent in the mature/older leaves. Carbamazepine concentration in cucumber fruits and leaves was negatively correlated with soil organic matter content. The concentrations of CBZ in the roots and stems were relatively low, and most CBZ in the plant (76-84% of total uptake) was detected in the leaves. A greenhouse experiment using fresh water and reclaimed wastewater spiked, or not, with CBZ at 1 μg L−1 (typical concentration in effluents) revealed that CBZ can be taken up and bioaccumulated from its background concentration in reclaimed wastewater. Bioaccumulation factor (calculated as the ratio of CBZ concentration in the plant to that in the soil solution) for the fruits (0.8-1) was significantly lower than the value calculated for the leaves (17-20).This study emphasizes the potential uptake of active pharmaceutical compounds by crops in organic-matter-poor soils irrigated with reclaimed wastewater and highlights the potential risks associated with this agricultural practice.  相似文献   
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东非地区的海洋保护区:它们取得了多大的成功?   总被引:3,自引:0,他引:3  
本文探讨了东非地区海洋保护区(MPA)及其所包含的珊瑚礁的管理。这一地区包括科摩罗、肯尼亚、马达加斯加、毛里求斯、莫桑比克、坦桑尼亚以及塞舌尔。  相似文献   
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