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1.
Cristina Munari 《Marine pollution bulletin》2010,60(7):1040-170
The potential of four benthic indices (AMBI/M-AMBI, BENTIX, BITS) was assessed in Italian coastal transitional ecosystems. The community composition showed a strong dominance of lagoonal, tolerant species, and out of more of 400 species found, only about 40 taxa were dominant. The full agreement of the four indices on an undegraded (Good or better) or degraded (Moderate or worse) status occurred only in 32.3% of stations. This study evidenced that BENTIX is inappropriate for eutrophic Adriatic lagoons, and that in such environments M-AMBI classification is actually too much dependent on diversity and richness, and seems unable to capture some peculiarities of benthic assemblages in transitional waters. AMBI and BITS gave similar classifications despite the different level of taxonomic identification needed. The unmodified use of these indices might impair accurate assessment of ecological quality status and decision-making on the managers’ point of view. 相似文献
2.
双层堤基是应用较多的双面层的堤基构造类型,上层为弱透水层,下层为强透水深厚砂层。堤内弱透水层在汛期高水位时面临较高的水头承压,出现管涌的危险性极大。以实验室模拟分析的方式,专题探究双层堤管涌的悬挂型防渗控制规律,结果可知:悬挂型防渗墙在有效截断管涌迁移路径方面具有独特功能和阻滞效果,管涌没有出现之前,悬挂式防渗墙消解水头冲刷的作用一般不很明显,而一旦有管涌发生,防渗墙对透水堤基深入越深,防渗作用将越好,如果保持贯入度相同,则下游布置防渗墙比上游布置防渗墙效果要好。研究结果为同类工程应用提供研究和技术参考。 相似文献
3.
则木河断裂的现今活动方式及其地形变鉴别标志探讨 总被引：2，自引：0，他引：2
根据地壳形变测量资料,探讨了则木河断裂的现今活动方式及其定性的地形变鉴别标志问题。结果表明：则木河断裂的现今活动具有明显的分段性特征,即以大箐为界分为南北两段,北段以粘滑活动为主,南段以蠕滑活动为主;沿则木河断裂带垂直位移速率空间分布特征的显著差异,可以作为鉴别断裂现今活动方式的标志之一,其位移速率的相对大小,可作为鉴别断裂现今活动方式的一种参考标志 相似文献
4.
宁夏地下水监测现状调查及对策 总被引：1，自引：0，他引：1
[目的]针对地下水监测存在问题,提出改进地下水监测工作的对策和建议。[方法]调查地下水监测历史沿革及现状,理出存在主要问题,研究应对策略。[结果]宁夏地下水监测范围小,监测层位浅,监测井标准低老化严重,井网布局和监测项目与面临任务不适应,难以满足地下水管理与开发保护要求,亟需完善地下水监测井网。[结论]做好宁夏地下水监测站网总体规划,建立稳定资金投入机制,加强与国土部门合作,逐年完善地下水监测站网,是做好地下水监测工作主要举措。 相似文献
5.
《海洋通报(英文版)》2024,26(1):91-98
为深入贯彻落实习近平总书记关于新质生产力的一系列重要论述、重大部署,本文利用China National Knowledge Infrastructure(CNKI)网络数据库检索以新质生产力为主题的文献报道,从发文关键词、发文机构、研究领域等方面进行文献计量学分析.文献报道主要集中于2023-2024年,研究热点多为生产力和新质生产力.经分析,渔业领域相关研究尚处于起步阶段,其中,海洋渔业设施化、智能化和\"海上粮仓\"需进一步加强,为今后实现渔业领域\"新质生产力\"的目标提供技术支撑. 相似文献
6.
Janice Monk 《The Professional geographer》1994,46(3):277-288
Feminist geography is now widely practiced internationally, but its development is usually reviewed from a temporal rather than a spatial perspective. This article assesses the varying extent and nature of feminist geography across countries, attempting to interpret differences in terms of cultural contexts and disciplinary trends. It is intended to stimulate reflection and does not claim to offer definitive interpretations. 相似文献
7.
Three provenances ofPappophorum caespitosum, a forage native grass from the temperate arid region of Argentina, were studied to gain a physiological knowledge of the seasonal organic N status in response to adequate water supply and water stress conditions; and to assess the extent to which variations in the N status between these provenances arise under different water regimes. Plant part samples were analysed for free and bound organic N fractions. Water shortage resulted in a significant depression of plant growth in all provenances. Total N concentration declined along the annual cycle in both water treatments, but it was higher under water stress. The size of the free N pool was very large, suggesting that it may act like an osmoticum. Nitrogen use efficiency increases along the growing period, while the rate of N intake and the specific leaf N content decrease. Variability was found between provenances in most of the physiological and biochemical traits examined under both water regimes. 相似文献
8.
9.
Governance of solar geoengineering is important and challenging, with particular concern arising from commercial actors’ involvement. Policies relating to intellectual property, including patents and trade secrets, and to data access will shape private actors’ behavior and regulate access to data and technologies. There has been little careful consideration of the possible roles of and interrelationships among commercial actors, intellectual property, and intellectual property policy. Despite the current low level of commercial activity and intellectual property rights in this domain, we expect both to grow as research and development continue. Given the public good nature of solar geoengineering, the relationship between the public and private sectors would likely assume a procurement structure. Innovative policy approaches to intellectual property and data access that are specific to solar geoengineering are warranted. These current circumstances also present opportunities for the development of policy and norms that might soon be lost. We consider some possible approaches, and recommend a bottom‐up, primarily nonstate, voluntary “research commons” for patents and data that are related to solar geoengineering. This would facilitate information sharing and limit data fragmentation and trade secrecy. It would also provide an incentive for commons members to pledge to limit some forms of intellectual property acquisition and to assure access on reasonable terms, thereby limiting the need for enforcement. This should help reduce downstream barriers to innovation and to encourage the potential development of technologies at reasonable cost. Such a research commons might also catalyze the adoption of best practices in research and development. This article is categorized under:
- Policy and Governance > Private Governance of Climate Change
- Social Status of Climate Change Knowledge > Knowledge and Practice
10.
中国城市职能分类研究综述 总被引：5，自引：1，他引：5
城市职能分类的研究一直以来就是城市地理学研究的重要领域。在简要回顾中国城市职能分类研究的主要成果和观点的基础上，从研究的阶段性角度将城市职能分类分为研究初步展开、研究发展、研究逐步完善3个时期；并提出为适应新形势的发展，城市职能分类研究将在拓展研究对象、创新研究方法、完善数据指标体系、充分利用研究成果等方面得到完善和提高。 相似文献
