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红火蚁Solenopsis invicta是火蚁属重要的入侵蚂蚁,与其近缘种黑火蚁S. richteri和杂交蚁S. invicta × S. richteri形态相似,难以区分。为了快速准确鉴定3种火蚁属近缘种,本研究利用气相色谱-质谱联用仪(GC-MS),解析3种火蚁的工蚁、有翅雌蚁、有翅雄蚁的表皮碳氢化合物种类和含量,并进行主成分分析、判别分析及聚类分析。结果表明:3种火蚁共检测到62种表皮碳氢化合物,主要包括一甲基烷烃、二甲基烷烃和正构烷烃等;红火蚁、黑火蚁及杂交蚁不同品级的表皮碳氢化合物种类及含量存在显著的种间差异,红火蚁不同地理种群的表皮碳氢化合物种类及含量相似度较高;建立3种火蚁相应品级的分类判别函数,可准确区分各品级下的3种火蚁。因此,表皮碳氢化合物组成分析可用于红火蚁及其近缘种的分类鉴定,为口岸火蚁属蚂蚁的快速检疫鉴定提供新技术。  相似文献   
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红火蚁Solenopsis invicta Buren是国际最具危险性的入侵性物种之一,传播扩散速度快、适生能力强。云南由于其独特的地理和气候环境,给红火蚁的入侵和发生提供了丰富的栖息环境和食物。本研究对云南高海拔冷凉区域人工草坪条件下红火蚁婚飞有翅蚁、工蚁活动规律,以及蚁巢变化规律进行了系统的调查研究。结果表明,在人工草坪条件下,红火蚁婚飞活动主要发生在每年的5-8月,6月初和8月初为婚飞生殖蚁发生高峰期,婚飞生殖蚁数量分别达到390.33头/1 000 m^2和523.33头/1 000 m^2,分别占到全年婚飞生殖蚁总量的25.19%和33.77%;诱集工蚁数量在6月下旬-7月上旬、8月下旬-9月下旬达到两个高峰,合计诱集数量分别为634.66头/1 000 m^2和1 636.00头/1 000 m^2,分别占到全年诱集工蚁总量的44.59%和17.30%;新增蚁巢数量在6月1日-7月1日、8月16日、9月15日-12月16日、次年3月14日-4月15日为4个增长阶段,新增蚁巢数量分别为9.66个/1 000 m^2、4.33个/1 000 m^2、5.67个/1 000 m^2、2.00个/1 000 m^2、分别占到全年新增蚁巢总数的44.62%、20.00%、26.15%、9.23%。综合婚飞年度规律、全年诱集工蚁数量、活动蚁巢数量和新增蚁巢数量方面的结果,人工草坪条件下,6-9月为红火蚁的活动发生高峰期,结合当地的实际情况,建议每年的4-6月和8-9月采用毒饵与粉剂相结合的方式进行防治,在12月份采用低毒农药灌巢进行防治。  相似文献   
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红火蚁Solenopsis invicta Buren工蚁活动能力与蚁群健康、环境条件等密切相关,对蚁群进行干扰会引起工蚁防卫和攻击行为。本文采用标尺插入法对蚁巢进行干扰破坏,测定了工蚁活动性指数,结果显示在相同干扰程度下活动性指数随蚁巢体积增大而增大,相同蚁巢时随着干扰程度增加而活动性指数先迅速增大后基本保持不变。间隔5 min对蚁巢实施连续干扰后工蚁活动性呈明显连续下降趋势,第5次干扰后工蚁的响应活动变得很弱,工蚁活动性指数与干扰时间之间关系符合二次曲线方程。  相似文献   
25.
Ant‐lycaenid associations range from mutualism to parasitism and the caterpillars of some species of lycaenids are reported to enter ant nests for shelter, diapause, or pupation. The present study aimed to examine the nature of the association between Euchrysops cnejus (Fabricius) (Lepidoptera: Lycaenidae) and Camponotus compressus (Fabricius) (Hymenoptera: Formicidae) worker ants on the extrafloral nectary‐bearing cowpea plant, Vigna unguiculata (L.) Walp. (Fabaceae). The abundance patterns of the ants and the lycaenid caterpillars together with the spatial patrolling patterns of the ants on the plants revealed that ant abundance increased with the occurrence of the lycaenid caterpillars and the ants preferred the lycaenids over the extrafloral nectar. Camponotus compressus worker ants constructed a shelter at the cowpea plant base after interaction with one or more lycaenid caterpillar(s) and tended the caterpillars and pupae till the emergence of the butterfly. The ant‐constructed shelters (ACSs) inhabited by the minor caste workers (13 ± 1.3 ants per ACS), were utilized by the caterpillars to undergo pupation. The ants confined their activities predominantly to tending the pod‐feeding caterpillars and the solitary pupa within each ACS. It appears that the behavior of the tending worker ants is modulated by the lycaenid vulnerable stages.  相似文献   
26.
《环境昆虫学报》2015,37(4):790-794
准确获得红火蚁Solenopsis invicta Buren发生程度数据是做好防控工作的基础和前提,明确不同调查方法之间的定量关系可为建立该蚁发生程度度量的标准化体系提供依据。本研究比较了应用诱饵诱集法和陷阱法获得的红火蚁工蚁数量,并分析了二者的相关性,建立了模型。累计设置了840个诱饵,共诱集到183753头工蚁;设置840个陷阱,共收集工蚁93787头。一年中不同时期诱饵诱集法采集的工蚁数量以4月-6月最多,为285.8头/诱饵;陷阱法是7月-8月,为171.7头/陷阱。诱集法、陷阱法收集到的工蚁数量极显著相关,描述该关系的6个模型分别为Y=0.2693X+27.9010(1月-3月)、Y=0.2309X+22.6450(11月-12月)、Y=0.2818X+61.1160(4月-6月)、Y=0.6219X+28.1070(7月-8月)、Y=0.3067X+32.2510(9月-10月)、Y=0.3635X+32.2510(1月-12月)。本研究结果对建立红火蚁发生程度主要指标的转换体系具有参考意义。  相似文献   
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相对于传统生化测定方法,基于近红外光谱(Near infrared spectroscopy,NIRS)玉米籽粒蛋白质含量检测是一种快速、非破坏、且适用于多组分同时检测的新方法。但在建模过程中,由于奇异数据(异常值)的存在会影响近红外光谱模型的预测精度和稳定性,我们采用奇异数据筛选法剔除了玉米籽粒近红外光谱中的奇异数据并建立了玉米籽粒蛋白质含量的偏最小二乘支持向量机(Least squares support vector machine,LS-SVM)模型。本文分别采用杠杆值法(Leverage)、半数重采样法(Resampling by Half-Mean,RHM)和蒙特卡洛采样法(Monte-Carlo Sampling,MCS)剔除了玉米籽粒蛋白质光谱数据中的奇异数据并对模型结果进行比较。在剔除奇异数据的基础上,采用偏最小二乘回归法(Partial least squares regression,PLSR)提取主成分,并基于小生境蚁群算法(Niche ant colony algorithm,NACA)优化偏最小二乘支持向量机(LS-SVM)模型参数(γ和σ2),建立基于LS-SVM的玉米籽粒蛋白质定量分析模型。结果表明,采用3种奇异数据筛选法剔除奇异数据后所建LS-SVM模型的预测结果都优于采用原光谱数据所建模型,相比较而言,蒙特卡洛采样法为基于近红外光谱检测玉米籽粒蛋白质的最佳奇异数据筛选法。  相似文献   
29.
Integrating occupational safety and health (OSH) into life cycle assessment (LCA) may provide decision makers with insights and opportunities to prevent burden shifting of human health impacts between the nonwork environment and the work environment. We propose an integration approach that uses industry‐level work environment characterization factors (WE‐CFs) to convert industry activity into damage to human health attributable to the work environment, assessed as disability‐adjusted life years (DALYs). WE‐CFs are ratios of work‐related fatal and nonfatal injuries and illnesses occurring in the U.S. worker population to the amount of physical output from U.S. industries; they represent workplace hazards and exposures and are compatible with the life cycle inventory (LCI) structure common to process‐based LCA. A proof of concept demonstrates application of the WE‐CFs in an LCA of municipal solid waste landfill and incineration systems. Results from the proof of concept indicate that estimates of DALYs attributable to the work environment are comparable in magnitude to DALYs attributable to environmental emissions. Construction and infrastructure‐related work processes contributed the most to the work environment DALYs. A sensitivity analysis revealed that uncertainty in the physical output from industries had the most effect on the WE‐CFs. The results encourage implementation of WE‐CFs in future LCA studies, additional refinement of LCI processes to accurately capture industry outputs, and inclusion of infrastructure‐related processes in LCAs that evaluate OSH impacts.  相似文献   
30.
ABSTRACT Social control of egg-laying rate in queens of the fire ant (Solenopsis invicta Buren) was studied by experimental manipulation of the number of larvae, pupae and workers in colonies, and the age and size of larvae and workers. Workers and pupae do not stimulate oviposition by queens. The number of fourth instar larvae, on the other hand, bears a positive log-log relationship to the queen's egg-laying rate. Such larvae are needed both to stimulate and maintain oviposition. Their withdrawal results, within 48 h, in a decline in queen oviposition almost to zero. Their addition to broodless nests results in peak laying in about 4 days. Larvae in the first three stadia and early in the fourth stadium have a much lower effect upon queen fecundity. Sexual larvae are only c. 5% as stimulating on a weight basis, but equivalent on an individual basis. Several associated measures are positively correlated to egg-laying rate: weight of the queen, the number of her vitellogenic follicles per ovariole, total vitellogenic follicles, the time she spends feeding and (usually) the number of workers in the retinue that cares for her. The egg volume is negatively correlated with laying rate, so that queens lay more eggs for the same expenditure of material as laying rate increases. As body size of workers increases, they become less effective in transmitting the larval stimulation to the queen, but worker age has no effect on this ability. For a given number of larvae, queens in small, naturally growing colonies lay fewer, larger eggs than do queens in experimental colonies, but their fecundity increases more rapidly in relation to number of larvae. When larvae are fed vital-dyed food in one experimental colony, and then transferred to an undyed colony, the dye is rapidly transferred to worker crops, and into the queen's eggs, indicating bulk movement of material from larvae to workers to the queen and eggs. Large larvae are more effective at this than small larvae. Fourth instar larvae may be a digestive and metabolic caste that processes protein for egg production by the queen. If that is the case, the queen and fourth instar larvae are linked in a positive feedback loop. Either the logarithmic relation of fecundity to larval numbers or physical limits of the queen may set the maximum egg-laying rate, and thus determine maximum colony size. The data do not allow a clear choice between these alternatives.  相似文献   
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