Characterization of Chiton <Emphasis Type="Italic">Ischnochiton hakodadensis</Emphasis> Foot Based on Transcriptome Sequencing     

Huaiqian Dou  Yan Miao  Yuli Li  Yangping Li  Xiaoting Dai  Xiaokang Zhang  Pengyu Liang  Weizhi Liu  Shi Wang  Zhenmin Bao 《中国海洋大学学报(英文版)》2018,17(3):632-640

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国土空间规划:产业空间配置类单幅总图的研制     

余建辉  李佳洺  张文忠  王岱 《地理研究》2019,38(10):2486-2495

省级空间规划中的产业空间配置是在“三区三线”划分基础上进一步明确地域功能、引导地域功能格局优化的必要步骤。在综合考虑方法的创新性和成熟度基础上,对在“三区三线”格局内进行产业空间配置的逻辑架构、技术方法、数据体系等内容进行定量和定性相结合的探索性分析,形成了主导产业筛选、产业园区适宜规模识别、重点产业空间识别等流程体系,共同合成了一套用以研制空间规划中的产业空间配置类单幅总图的技术方法。其中,在主导产业筛选体系中综合考虑了产业关联、产业发展基础、发展潜力和政策支持等方面,在产业园区适宜规模识别体系中综合考虑了产业园区级别、园区产业是否切合区域产业发展导向、园区产业发展程度、与各类红线及城镇的空间关系等指标,并从微观企业入手向上总结重点产业空间范围,结合“三区三线”的国土空间适宜性、城镇空间划分结果进行空间叠加,做到了对省级重点产业空间的有效识别和落地。同时,以福建省为案例进行了实践分析。  相似文献   

Spatio-temporal analysis of the human footprint in the Hengduan Mountain region: Assessing the effectiveness of nature reserves in reducing human impacts     

Yin  Le  Dai  Erfu  Zheng  Du  Wang  Yahui  Ma  Liang  Tong  Miao 《地理学报(英文版)》2020,30(7):1140-1154

Mapping the human footprint(HF) makes it possible to quantify human influence, which has had an unprecedented impact on the global ecosystem. Using five categories of human pressure data, this study mapped the HF of the Hengduan Mountain region and assessed the effectiveness of nature reserves in reducing human impacts. The results showed that the HF of the Hengduan Mountain region was generally higher in the south and lower in the north. The HF increased by 11.24% over the past 25 years, with faster growth in the southeast. The HF growth rate in nature reserves was much lower than that across the region, which indicated that nature reserves played an important role in reducing the impact of human pressure. A study of Baimaxueshan nature reserve found that establishing nature reserves could effectively reduce the impact of human activities, and no "leakage" occurred. Population growth was an important reason for the increased HF in nature reserves. The development of ecotourism in nature reserves must be based on ecological protection. Strengthening the long-term monitoring, evaluation, and management of nature reserves is a basic requirement for their long-term development.  相似文献   

Characteristic Test Study on Bearing Capacity of Suction Caisson Foundation Under Vertical Load     

Dai  Guo-liang  Zhu  Wen-bo  Zhai  Qian  Gong  Wei-ming  Zhao  Xue-liang 《中国海洋工程》2020,34(2):267-278

Suction caisson foundations are often subjected to vertical uplift loads, but there are still no wide and spread engineering specifications on design and calculation method for uplift bearing capacity of suction caisson foundation.So it is important to establish an uplift failure criterion. In order to study the uplift bearing mechanism and failure mode of suction caisson foundation, a series of model tests were carried out considering the effects of aspect ratio,soil permeability and loading mode. Test results indicate that the residual negative pressure at the top of caisson is beneficial to enhance uplift bearing capacity. The smaller the permeability coefficient is, the higher the residual negative pressure will be. And the residual negative pressure is approximately equal to the water head that causes seepage in the caisson. When the load reaches the ultimate bearing capacity, both the top and bottom negative pressures are smaller than Su and both the top and bottom reverse bearing capacity factors are smaller than 1.0 in soft clay. Combined the uplift bearing characteristics of caisson in sandy soil and soft clay, the bearing capacity composition and the calculation method are proposed. It can provide a reference for the engineering design of suction caisson foundation under vertical load.  相似文献   

近年来横沙东滩围垦区前沿地形演化规律及驱动因素分析   总被引：1，自引：1，他引：0  

郭兴杰  王寒梅  史玉金  杨忠勇  孙杰  戴清清 《海洋学报》2019,41(11):142-149

河口大型滩涂演化关系到航运通畅、生态保护以及近岸工程的安全性，也是地貌学和工程界关注的热点。本文选择横沙东滩围垦区前沿5 m等深线包络区域作为研究区，2011–2017年间利用单波束测深系统对研究区进行持续性高精度监测，并结合近年来流域来沙、河口工程的建设和极端气候变化等影响因素分析其冲淤格局。结果表明:(1)近年来横沙东滩基本呈中间淤涨、周围冲刷的态势，整体由工程前“长大不长高”转化为工程后的“长高不长大”的演化格局；(2)海域来沙是此区域淤积的主要物源，研究区两侧涨落潮流路分异引起的环流是导致此区域淤积的主要动力；(3)深水航道堤坝工程、横沙东滩围垦工程等是导致研究区中间淤涨的原因；(4)人类活动可以直接影响滩槽的演化格局，工程建设的固定制约了河槽和滩涂的摆动，但也加剧了研究区局部的冲刷，未来应注意其内部串沟的发展，防止其连通威胁堤坝和滩涂的稳定。  相似文献   

Ecological Network Analysis Quantifying the Sustainability of Regional Economies: A Case Study of Guangdong Province in China     

Jinshe Liang  Ke Hu  Teqi Dai 《中国地理科学(英文版)》2018,28(1):127-136

To meet the challenge of sustainable development, sustainability must be made. Ecological network analysis(ENA) was introduced in this paper as an approach to quantitatively measure the growth, development, and sustainability of an economic system. The Guangdong economic networks from 1987 to 2010 were analyzed by applying the ENA approach. Firstly, a currency flow network among economic sectors was constructed to represent the Guangdong economic system by adapting the input-output(I-O) table data. Then, the network indicators from the ENA framework involving the total system throughput(TST), average mutual information(AMI), ascendency(A), redundancy(R) and development capacity(C) were calculated. Lastly, the network indicators were analyzed to acquire the overall features of Guangdong's economic operations during 1987–2010. The results are as follows: the trends of the network indicators show that the size of the Guangdong economic network grows exponentially at a high rate during 1987–2010, whereas its efficiency does not present a clear trend over its whole period. The growth is the main characteristic of the Guangdong economy during 1987–2010, with no clear evidence regarding its development. The quantitative results of the network also confirmed that the growth contributed to a great majority of the Guangdong economy during 1987–2010, whereas the development's contribution was tiny during the same period. The average value of the sustainability indicator(α) of the Guangdong economic network was 0.222 during 1987–2010, which is less than the theoretically optimal value of 0.37 for a sustainable human-influenced system. The results suggest that the Guangdong economic system needs a further autocatalysis to improve its efficiency to support the system maintaining a sustainable evolvement.  相似文献   

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易重海  朱建军  陈永奇  戴吾蛟 《大地测量与地球动力学》2010,30(6):71-76

????????????????????????????????????????????????????÷??????????????GPS????????е???????????????λ??????IGS????????????????????????????ν???????????????????????????????????仯??????????????????????????????????仯????????????????????????仯?????????????????????????????仯?,??????????????????????????????ó???????????????????????????????????У??????????????????????????t????????????????????ж???????????????????????λ????????峱???????????????????????????÷???????δ?????????????????????????????????????????????????????  相似文献   

小波分解与EMD在变形监测应用中的比较   总被引：1，自引：0，他引：1  

罗飞雪  戴吾蛟 《大地测量与地球动力学》2010,30(3)

为分析经验模式分解(Empirical Mode Decomposition, EMD)在GPS动态变形监测应用中的可行性和有效性,利用模拟数据和振动台的GPS实测数据分析比较了EMD和小波分析在信号去噪和多尺度分解上的能力.结果表明:EMD和小波均能较准确地提取结构振动信息,但当噪声较大时小波去噪和多尺度分解稳定性略优于EMD,而EMD则基于数据本身具有自适应性,不受小波基选择和分解层数的影响.  相似文献   

Eco-geographic environment and regional development in Xinjiang of China     

Fuqiang Xia  Erfu Dai  Du Zheng  Shaohong Wu  Qinye Yang 《中国地理科学(英文版)》2010,20(1):74-83

The study on relationship between eco-geographic environment (EGE) and regional development (RD) is of theoretical and practical significance to promote the comprehensive study on nature and human factors and regional coordination development. Based on the evaluation index system and models of EGE and RD, Quadrant Analysis Method (QAM) and the Coordination Degree and Coordinated Development Degree Model (CDCDDM) were applied to studying the relationship between EGE and RD in Xinjiang in this paper. The results show that Xinjiang can be divided into four type regions according to the relationship between EGE and RD, namely high coordination region (HCR), overloading development region (ODR), low coordination region (LCR) and potential development region (PDR). Most areas of Xinjiang belong to LCR which can not bear a larger population and support large-scale economic development. HCR, ODR and PDR, which are mainly distributed in piedmont oases and take basin as unit, should be focused on in the development of Xinjiang. The EGE has great influence on RD, and there is serious contradiction between them. Relevant suggestions on development strategies were put forward according to the character of different type regions, and the key regions of macro-layout of RD in Xinjiang were pointed out.  相似文献   

1961—2008年内蒙古降水极端事件分析   总被引：4，自引：0，他引：4       下载免费PDF全文

尤莉  戴新刚  张宇 《气候变化研究进展》2010,6(6):411-416

利用内蒙古自治区116个气象站1961—2008年逐日降水量资料,以年序列的第90和95个百分位,分别建立了单站日降水量极端气候事件的阈值,检测了近48年来内蒙古逐日降水量极端事件的出现频率,分析了极端事件阈值、频数及降水量的空间分布和年际、年代际及季节变化的差异,对比分析了1987年前后极端事件频次和降水量的变化。结果显示：1) 内蒙古日降水极端事件的阈值普遍较小,在2.1～23.8 mm之间;全年极端事件出现的频次在2.4～20.9 d之间;降水极端事件的阈值、频次、降水量等空间差异十分明显。2) 近48年来内蒙古区域平均的夏季和全年降水极端事件没有显著的增减变化趋势,但进入21世纪后,7—8月内蒙古极端降水事件和极端事件的降水量明显减少。3) 1987年气温显著升高以后,中部大部地区和东南部降水极端事件减少,东北部大部和西部增加。  相似文献