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121.
Climate change strongly affected the structure and functions of natural ecosystems, e.g. the vegetation productivity decreased in the Northeast permafrost region due to the higher temperature and less precipitation, whereas in the Tibetan Plateau, the vegetation productivity increased, owing to the improved thermal resource. Climate change led to reduced precipitation in North and Northeast China and thus the reduced surface runoff. The public needs for energy were changed because of climate change, e.g. the shorter heating period in winter. Climate change profoundly influenced human health, pathophoresis and major projects by increasing extreme events, including frequency and magnitude, and causing more serious water shortage. Under the background of climate change, although the improved thermal resources can be helpful for extending the crop growth period, more extreme events may resulted in more instability in agricultural productivity. Not only did climate change indirectly affect the secondary and tertiary industries through the impacts on agriculture and natural resources, but also climate change mitigation measures, such as carbon tax, tariff and trading, had extensive and profound influences on the socioeconomic system. Further analysis indicated that the impact of climate change presented significant regional differences. The impact had its pros and cons, while the advantages outweighed the disadvantages. Based on the above analysis on the impacts of climate change, we put forward suggestions on coping with climate change. First, scientifically dealing with climate change will need to seek advantages while avoiding the disadvantages of climate change in order to achieve the orderly adaptation to climate change, which is characterized with “Overall best, long-term benefit.” Second, quantitative adaptation should be given more attention, e.g. proposing operational schemes and predictable goals and using uncertainty analysis on adaptation measures. Third, more active coping strategy should be adopted to enhance China’s future comprehensive competitiveness. The strategies include but are not limited to gradually adjusting the industrial structure, intensifying the research and development (R&D) of emission reduction technology and actively responding to the influence of carbon tax, tariff and trading on socioeconomic development in China.  相似文献   
122.
Abstract

Pheromones can be used as leafhopper attractants. However, commercial pheromone products, such as the Ingle lure, have certain limitations, including poor persistence in the field. In this study, (E)-2-hexenal, (Z)-3-hexen-1-ol, (Z)-3-hexenyl acetate, (E)-ocimene, linalool, and geraniol were selected and behaviorally tested as potential leafhopper attractants. Y-tube olfactometer tests showed that the C2 formulation was more effective than other formulations. In tea field trials, the number of leafhoppers caught by sticky board traps baited with C2 lures was greater than that caught by treatment. The number of leafhoppers attracted by the C2 lures was greater than that attracted by the commercial Ingle lures. Additionally, the total amount of active C2 components on lures was greater than that of the active components on the lure after 14 days. Thus, the results indicated that the C2 formulation may attract leafhoppers and have a greater persistence than other formulations in tea field.  相似文献   
123.
危险装置操作人员职业适应性研究的策略和方法   总被引:1,自引:1,他引:1  
重大危险装置操作人员所涉及的是危险性高、责任重大的工种。这些工种也对从业人员在生心素质上提出了较为严格的要求。以“重大危险装置操作人员”为研究对象,面向一个工种群的职业适应性研究展开了探讨,提出了作业性质类别的概念和“抽取类别、交叉对应”的技术路线,概括了人在生理、心理方面与职业活动有关的二十七项指标,论述了重大危险装置操作人员所涉及的工种与职业适应性指标之间的关系。  相似文献   
124.
灯心草部分生理生化指标对土壤复合重金属胁迫的响应   总被引:1,自引:0,他引:1  
通过盆栽试验,以叶绿素含量和POD、SOD、CAT3种抗氧化酶活性作为观测指标,研究了Cu、Cd、Pb、Zn和As复合重金属胁迫下灯心草部分生理生化指标的变化趋势和机理.结果表明,灯心草的生理毒害效应呈明显的剂量-效应关系.表现为与对照相比,叶绿素含量减少,叶绿素a/b值降低,叶片失绿现象明显.随着复合重金属胁迫浓度的增加,灯心草3种酶活性均呈先升后降的变化趋势,但出现抗性酶活性高峰所对应的重金属浓度不同,表现出不同的特征变化趋势.总体来说,在接近土壤环境质量标准低浓度设计范围内,酶活性有逐渐被激活的趋势.但在高浓度水平下,酶活性普遍受到抑制.生长在铅锌尾矿和模拟矿毒水污染土壤中的灯心草叶绿素合成受到显著抑制(P<0.05),但POD和CAT两种酶活性均高于对照.  相似文献   
125.
螯合型表面活性剂强化黑麦草修复Cd污染水体   总被引:1,自引:0,他引:1  
采用水培试验,研究了新型螯合型表面活性剂N-十二酰基乙二胺三乙酸钠(LED3A)强化黑麦草修复Cd污染水体的效果,探讨了Cd或/和LED3A存在下黑麦草的生理响应以及LED3A对黑麦草除Cd性能的影响.结果表明:Cd显著抑制黑麦草生物量和光合色素含量,添加LED3A后抑制作用略有增强,CL100处理叶绿素和类胡萝卜素含量较CL0分别降低了15.50%和8.18%. LED3A对黑麦草的生长无显著影响,对黑麦草细胞的相对电导率(REC)有一定的提高,可使细胞膜渗透性增加以利于黑麦草对Cd的吸收.Cd胁迫下适量添加LED3A,能提高黑麦草植株超氧化歧化酶(SOD)和过氧化物酶(POD)活性,起到清除活性氧(ROS)、缓解Cd毒害和抑制丙二醛(MDA)积累的作用.最佳LED3A添加量下(50mg/L),黑麦草植株的总Cd累积量和转移系数较Cd单独处理时分别提高了74.39%和67.96%,Cd的去除率达到55.98%.研究表明添加LED3A可有效提高植物对Cd的修复效率.  相似文献   
126.
To find suitable wetland plants for constructed wetland-microbial fuel cells(CW-MFCs),four commonly used wetland plants, including Canna indica, Cyperus alternifolius L., Acorus calamus, and Arundo donax, were investigated for their electrogenic performance and physiological changes during non-growing seasons. The maximum power output of12.82 mW/m~2 was achieved in the A. donax CW-MFC only when root exudates were being released. The results also showed that use of an additional carbon source could remarkably improve the performance of electricity generation in the C. indica and A. donax CW-MFCs at relatively low temperatures(2–15°C). However, A. calamus withered before the end of the experiment, whereas the other three plants survived the winter safely, although their relative growth rate values and the maximum quantum yield of PSII(Fv/Fm) significantly declined, and free proline and malondialdehyde significantly accumulated in their leaves.On the basis of correlation analysis, temperature had a greater effect on plant physiology than voltage. The results offer a valuable reference for plant selection for CW-MFCs.  相似文献   
127.
Summary Feeding by the homopteranPsylla pyricola on leaves of pear trees induces the production of volatile compounds, such as (E,E)--farnesene and methyl-salicylate, as well as the production of polyphenols. The inference on induction is based on GC-MS and HPLC chromatograms from the same samples ofPsylla infested leaves, leaves from the same pear tree beforePsylla infestation and uninfested leaves from other pear trees.Psylla infestation greatly enhanced the production of volatiles ((E,E)--farnesene, methyl-salicylate and others) and triggered the production of new polyphenols, characterized by much longer retention times.However, the responses to infestation depend critically on leaf age (defined by leaf distance to apex). With respect to the leaf volatiles it appears that infested, old leaves produce fewer compounds and lower amounts of the volatiles than infested, young leaves. Moreover, there seem to be differences in pattern. Relative to (E,E)--farnesene, methyl-salicylate was found in much lower amounts in heavily infested, old leaves. With respect to polyphenols it was found that infested old leaves collected in August have polyphenols with the same retention times, but more or less equal amounts as uninfested young leaves collected in May. This shows thatPsylla infestation causes the induced response mostly in young leaves.The induced leaf volatiles may act as synomones to heteropteran bugs. As shown elsewhere,Anthocoris nemoralis responds significantly to (E,E)--farnesene and methyl-salicylate when offered in pure form against clean air in a Y-tube olfactometer. The effect of polyphenols on the performance ofP. pyricola is not yet known. Hence, a role in direct defence is still to be investigated.  相似文献   
128.
We examined variation in aggressive responses within and among individuals in the green frog, Rana clamitans. We tested the hypothesis that resident males respond in a graded fashion to changes in perceived intruder proximity (stimulus intensity). We also investigated how response level varied with responder body size. We found that green frogs differentially alter aggressive responses (increasing movement and calling rates while decreasing the duration and dominant frequency of their calls) with an increase in stimulus intensity. Body size did not appear to be a significant influence on most response levels. We suggest that aggressive responses are graded, and advertisement and aggressive calls represent opposite ends of a continuum. Green frogs do not exhibit clearly defined thresholds for responses like those reported for some other frogs. By using graded responses rather than discrete all-or-nothing responses, males may reduce the potential costs of aggressive encounters.  相似文献   
129.
氰戊菊酯和氯化镉暴露下日本青鳉的行为反应差异   总被引:4,自引:2,他引:2  
以天然河流中的日本青鳉(Oryzias latipes)行为变化规律为基础,采用水质安全在线生物预警系统(BEWs-1.1)对氰戊菊酯和氯化镉暴露下日本青鳉的行为反应进行了探讨.结果表明:1)在源水中,日本青鳉行为反应具有明显规律性,并表现出生物钟现象;2)氰戊菊酯和氯化镉连续暴露和间断暴露中,日本青鳉行为反应与污染物浓度和暴露时间均直接相关,并表现出相似的行为变化规律性,行为变化均符合生物行为的环境胁迫阈模型;3)高浓度(10mg·L-1)氯化镉间断暴露下的日本青鳉行为强度变化与低浓度(2mg·L-1)连续暴露下的行为强度变化差别不明显,而高浓度(10mg·L-1)氰戊菊酯间断暴露下的日本青鳉行为强度变化与低浓度(2mg·L-1)连续暴露时具有明显差异,高浓度暴露时产生了明显的行为毒性效应;4)器官损伤性污染物(如镉)引起的行为毒性效应在重新加入源水后可以得到部分恢复,而神经损伤性污染物(如氰戊菊酯)不可恢复,污染物不同的作用机理会影响水生生物的行为反应.  相似文献   
130.
In population modeling, a considerable level of complexity is often required to provide trustworthy results, comparable with field observations. By assuring sufficient detail at the individual level while preserving the potential to explore the consequences at higher levels, individual-based modeling may thus provide a useful tool to investigate dynamics at different levels of organization. Still, population dynamics resulting from such models are often at odds with observations from the field. This may be partly caused by a lack of focus on the individual dynamics under conditions of food stress and starvation. I developed a physiologically structured, individual-based simulation model to investigate life history of Daphnia and its effect on population dynamics in response to the productivity of the system. In verifying model behavior with available literature data on life history and physiology, I paid special attention to the dynamics of food intake and the verification of individual level results under conditions of food limitation and starvation. I show that the maximum filtering rates under low food levels used in the current model are much closer to measured filtering rates than the ones used in other models. Being consistent with results on physiology and life history from experiments at a wide range of food availability (including starvation), the model generates low amplitude or high amplitude population density cycles depending on the productivity of the system, as observed in field and experimental populations of Daphnia and with the minimum population densities being one to two orders of magnitude lower in the high amplitude than in the low amplitude cycles. To generate results which are not only qualitatively but also quantitatively comparable to experimental and field observations, however, a crowding effect on the filtering response has to be incorporated in the model.  相似文献   
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