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胡杨部分生态指标对塔里木河下游应急输水的响应   总被引:2,自引:0,他引:2  
向塔里木河下游应急生态输水对于胡杨为主体的荒漠河岸植被的恢复和自然更新产生了积极的影响.本文根据近5年对塔里木河下游阿拉干地区的大量野外调查数据,分析了应急输水对该地区地下水位上升及胡杨各项生态指标的影响.结果显示:随着应急生态输水的继续和扩大.塔河下游典型监测断面--阿拉干的地下水位逐渐抬升.水质得到改善,河道附近的地下水埋深已经由输水前的10~12 m抬升至5.5~6.2 m.胡杨的部分生态指标对输水有不同程度的响应;具体表现在,在垂直河道方向上,离河道越近胡杨各项生态指标,即盖度、郁闭度、冠幅、萌生枝、树冠疏失度以及次生苗和实生苗出现的频率等对输水的响应越显著.总体来说,在河道200m范围之内,生态输水对胡杨恢复的影响程度是显著的;在200~800m之间,为中度影响;800m以上的距离几乎无影响.  相似文献   
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Recent years have seen a sharp rise of attention to the importance of documentation in various disciplines in the social sciences. Many thinkers have found the concept of assemblages, which emphasizes complexity, heterogeneity, and emergence, fruitful for investigating the role of documents and documentation. This article analyses some examples from anthropology and management studies as contributions to documentary ethics, ontology, and politics. The first pair of case studies reveals a documentary activism of biological and therapeutic citizenship. The second pair shows how documentation works constitutively to bring different kinds of entities into being. Both kinds of cases practice a documentary politics, which is analyzed in terms of Bruno Latour’s ideas of “reassembling the social”.  相似文献   
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The actions of the individual extraocular muscles are best explained to medical students in a lecture format by showing the relationship of each muscle to the axes of the globe and the walls of the bony orbit. The lateral and medial rectus muscles cross only the vertical axis, and consequently, cause only abduction and adduction, respectively. These muscles can be tested simply by asking the patient to abduct or adduct. Inability to do so indicates that the muscles and/or their innervation have been compromised. In contrast, the superior and inferior oblique and rectus muscles cross all three axes (vertical, horizontal, and anteroposterior) of the globe. Therefore, concentric contraction of each of these muscles results in three movements; abduction or adduction, elevation or depression, and intorsion or extorsion. These muscles must be tested with a sequence of two movements. Gaze can be either elevated or depressed by both an oblique and a rectus muscle. If abduction or adduction occurs first, one muscle of the pair becomes incapable of causing elevation or depression of the pupil. The rationale for abducting or adducting first is that either the oblique or rectus muscle of the pair will no longer cross the horizontal axis and will then be unable to effect the desired movement. Inability to elevate or depress gaze from the abducted or adducted position shows which muscle, the oblique or rectus, and/or its innervation has been compromised. Anat Sci Ed 1:126–129, 2008. © 2008 American Association of Anatomists.  相似文献   
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In studies of firm's innovation performance, regression analysis can involve a significant level of model uncertainty because the ‘true’ model, and therefore the appropriate set of explanatory variables are unknown. Drawing on innovation survey data for France, Germany, and the United Kingdom, we assess the robustness of the literature on inbound open innovation to variable selection choices, using Bayesian model averaging (BMA). We investigate a wide range of innovation determinants proposed in the literature and establish a robust set of findings for the variables related to the introduction of new-to-the-firm and new-to-the-world innovation with the aim of gauging the overall healthiness of the literature. Overall, we find greater robustness for explanations for new-to-the-firm rather than new-to-the-world innovation. We explore how this approach might help to improve our understanding of innovation.  相似文献   
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