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201.
There have been numerous reports of genetic influences on division of labor in honey bee colonies, but the effects of worker genotypic diversity on colony behavior are unclear. We analyzed the effects of worker genotypic diversity on the phenotypes of honey bee colonies during a critical phase of colony development, the nest initiation phase. Five groups of colonies were studied (n = 5–11 per group); four groups had relatively low genotypic diversity compared to the fifth group. Colonies were derived from queens that were instrumentally inseminated with the semen of four different drones according to one of the following mating schemes: group A, 4 A-source drones; group B, 4 B-source drones; group C, 4 C-source drones; group D, 4 D-source drones; and group E, 1 drone of each of the A-D drone sources. There were significant differences between colonies in groups A-D for 8 out of 19 colony traits. Because the queens in all of these colonies were super sisters, the observed differences between groups were primarily a consequence of differences in worker genotypes. There were very few differences (2 out of 19 traits) between colonies with high worker genotypic diversity (group E) and those with low diversity (groups A-D combined). This is because colonies with greater diversity tended to have phenotypes that were average relative to colonies with low genotypic diversity. We hypothesize that the averaging effect of genotypic variability on colony phenotypes may have selective advantages, making colonies less likely to fail because of inappropriate colony responses to changing environmental conditions.  相似文献   
202.
There is a genetic component to plasticity in age polyethism in honey bee colonies, such that workers of some genotypes become precocious foragers more readily than do workers of other genotypes, in colonies lacking older bees. Using colonies composed of workers from two identifiable genotype groups, we determined that intracolony differences in the likelihood of becoming a precocious forager are a consequence of differences in rates of behavioral development that are also evident under conditions leading to normal development. An alternative hypothesis, that differences in the likelihood of becoming a precocious forager are due to differences in general sensitivity to altered colony conditions, was not supported. In three out of three trials, workers from the genotype group that was more likely to exhibit precocious foraging in single cohort colonies also foraged at relatively younger ages in colonies in which workers exhibited normal behavioral development. In contrast, in three out of three trials, workers from the genotype group that was more likely to exhibit precocious foraging in single-cohort colonies did not show disproportionately more overaged nursing in colonies in which workers exhibited delayed development. These results indicate that genotypic differences in plasticity in age-related division of labor are based on genotypic differences in rates of behavioral development.  相似文献   
203.
本文着重论述了完善的社会信用体系对于规范市场经济秩序,促进我国经济的持续、稳定、健康发展有着十分重要的意义。为此,档案行政管理部门应该主动找准自己的位置,履行自己的职责,并有所作为。从而充分发挥档案行政管理部门的自身优势,倾力打造跨行业、跨部门的信用档案信息平台。使全社会形成一种有序的竞争环境。  相似文献   
204.
The river continuum concept represents the most general framework addressing the spatial variation of both structure and function in river ecosystems.In the Mediterranean ecoregion,summer drought events and dams constitute the main sources of local disturbance to the structure and functioning of river ecosystems occurring in the river basin.In this study,we analysed patterns of spatial variation of detritus processing in a 7th order river of the Mediterranean ecoregion(River Tirso,Sardinia0Italy)and in three 4th order sub-basins which were exposed to different summer drought pressures.The study was carried out on phragmites australis and Alnus glutionsa leaf detritus at 31 field sites in seasonal field experiment Detritus processing rates were higher for Alnus glutionsa than for Phragmites australis plant detritus.Processing rates of Alnus glutionsa leaves varied among seasons and study sites from 0.006d^-1 to 0.189d^-1 and those of Phragmites australis leaves ranged from 0.0008d^-1 to 0.102d^-1,with the lowest values occurring at sites exposed to summer drought.Seasons and sites accounted for a significant proportion of such variability.Alder detritus decay rates generally decreased with increasing stream order,while reed detritus decay rates generallyincreased on the same spatial gradient.Summer drought events affected these spatial patterns of variation by influencing significantly the decay rates of both plant detritus.The comparisons among and within sub-basins showed strong negative influence of summer drought on detritus processing rates.Similarly,in the entire River Tirso basin decay rates were always lower at disturbed than at undisturbed sites for each stream order;decay rates of reed detritus remained lower at those sites even after the end of the disturbance events,while alder decay rates recovered rapidly from the summer drought perturbations.The different recovery of the processing rates of the two leaves could also explain the different patterns of spatial variation observed between the two leaves.  相似文献   
205.
治理酸雾的环保措施   总被引:1,自引:0,他引:1  
润滑油酸碱精制装置产生酸渣,装车时酸雾大量地散发到空气中,对环境的污染很严重;通过采取密闭装车环保治理措施,从而有效解决酸雾对环境的污染问题。  相似文献   
206.
宋留  杨冲  张辉  刘鸿斌 《中国环境科学》2018,38(7):2564-2571
针对造纸废水处理系统的时变性、非线性和复杂性等特点,本文提出一种基于高斯过程回归的软测量模型.基于平方指数协方差、线性协方差和周期性协方差函数组合构建了7种高斯过程回归模型,分别对出水化学需氧量和出水悬浮固形物浓度进行回归预测.此外,还对比了多元线性回归模型、主成分回归模型、偏最小二乘模型、人工神经网络模型和高斯回归模型的预测效果.对比计算结果表明无论是对输出变量的训练拟合还是预测,高斯过程回归模型的拟合效果均优于非高斯过程回归模型.高斯过程回归模型的预测结果表明:对于出水化学需氧量,线性协方差函数与周期性协方差函数的组合模型可以取得最好的预测结果;对于出水悬浮固形物,平方指数协方差函数与线性协方差函数组合模型可以取得最好的预测结果.  相似文献   
207.
农村生活污水处理工艺优选方法研究   总被引:1,自引:0,他引:1  
结合太湖流域农村生活污水处理的要求,筛选出目前太湖流域农村所采用的5种主要污水处理工艺,从经济、技术和运行管理3个层面确定了6个评价指标。基于熵权理论和灰色关联分析理论,建立了太湖流域农村生活污水处理工艺优选的熵权灰色关联分析模型。对备选方案与理想方案的关联度分析,得出工艺的优劣排序,并进行了评价结果的分析,为农村生活污水处理的工艺选择提供了较好的参考依据。  相似文献   
208.
The socio-ecological model (SEM) links ecological factors with characteristics of social systems and allows predictions about the relationships between resource distribution, type of competition and social organisation. It has been mainly applied to group-living species but ought to explain variation in social organisation of solitary species as well. The aim of this study was to test basic predictions of the SEM in two solitary primates, which differ in two characteristics of female association patterns: (1) spatial ranging and (2) sleeping associations. Beginning in August 2002, we regularly (re-)captured and marked individuals of sympatric populations of Madame Berthe's and grey mouse lemurs (Microcebus berthae, Microcebus murinus) in Kirindy Forest (Madagascar). We recorded data on spatial patterns, feeding and social behaviour by means of direct observation of radio-collared females. The major food sources of M. berthae occurred in small dispersed patches leading to strong within-group scramble competition and over-dispersed females with a low potential for female associations. In contrast, M. murinus additionally used patchily distributed, high-quality (large) resources facilitating within-group contest competition. The combined influence of less strong within-group scramble and contest as well as between-group contest over non-food resources allowed females of this species to cluster in space. Additionally, we experimentally manipulated the spatial distribution of food sources and found that females adjusted their spatial patterns to food resource distribution. Thus, our results support basic predictions of the SEM and demonstrated that it can also explain variation in social organisation of solitary foragers.  相似文献   
209.
210.
Many of the challenges conservation professionals face can be framed as scale mismatches. The problem of scale mismatch occurs when the planning for and implementation of conservation actions is at a scale that does not reflect the scale of the conservation problem. The challenges in conservation planning related to scale mismatch include ecosystem or ecological process transcendence of governance boundaries; limited availability of fine‐resolution data; lack of operational capacity for implementation; lack of understanding of social‐ecological system components; threats to ecological diversity that operate at diverse spatial and temporal scales; mismatch between funding and the long‐term nature of ecological processes; rate of action implementation that does not reflect the rate of change of the ecological system; lack of appropriate indicators for monitoring activities; and occurrence of ecological change at scales smaller or larger than the scale of implementation or monitoring. Not recognizing and accounting for these challenges when planning for conservation can result in actions that do not address the multiscale nature of conservation problems and that do not achieve conservation objectives. Social networks link organizations and individuals across space and time and determine the scale of conservation actions; thus, an understanding of the social networks associated with conservation planning will help determine the potential for implementing conservation actions at the required scales. Social‐network analyses can be used to explore whether these networks constrain or enable key social processes and how multiple scales of action are linked. Results of network analyses can be used to mitigate scale mismatches in assessing, planning, implementing, and monitoring conservation projects. Discordancia de Escalas, Planificación de la Conservación y el Valor del Análisis de Redes Sociales  相似文献   
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