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101.
探究农业科技园区的时空格局及影响因素对于优化园区布局、促进区域农业高质量发展具有重要意义。本文以黄河流域国家和省级农业科技园区为对象,采用标准差椭圆、核密度估计、探索性空间数据分析、空间变差函数、地理探测器模型等方法,分析了2001—2021年园区时空格局、演化特征及影响因素。结果发现:(1)农业科技园区经历了试点建设(2001—2009年)、全面推广(2010—2016年)和创新提质(2017—2021年)3个阶段。(2) 2001—2021年国家和省级园区总体分布态势逐渐一致,已经形成了河湟谷地、关中平原和黄河下游冲积平原3个主要集中分布区。(3)国家和省级园区全局关联特征表现不同,前者空间关联从随机模式向集聚模式转变,后者则一直表现为集聚模式;局部关联格局则均表现为“同向集聚增强,异向集聚减弱”的特点。(4)国家和省级园区格局演化均同时受结构性和随机性因素影响,包括产业结构水平、经济实力基础、交通便捷度、专利授权件数、农作物种植规模等主要因素,各因素间的交互作用大于单因素的作用,特别是产业结构水平与交通便捷度、经济实力基础与交通便捷度交互作用最为突出。本研究有助于丰富和完善农业科...  相似文献   
102.
罗燊  叶超 《地理学报》2023,78(1):241-255
“四个面向”(面向世界科技前沿、面向经济主战场、面向国家重大需求、面向人民生命健康)已成为新时代中国科学发展的指针。治理是一个反映“四个面向”的国际前沿研究领域,也是地理学和其他学科研究的焦点。围绕地理学如何应对治理这一关键问题,基于人地耦合的理念,系统梳理国内外地理学进行治理研究的轨迹与特点,从价值、思想、方法、技术4个维度发掘面向治理的地理学发展路径,紧密联系地理学发展动态及治理现代化的实践,从基础研究、平台建设、人才培育3个方面提出发展策略。提升中国地理学在国际治理研究中的影响力,促进地理学与其他学科的交叉融合,将自然与人文有机结合的理念应用于社会治理,增进居民福祉,并服务国家战略和区域可持续发展。  相似文献   
103.
This paper examines invasive animal management institutions, using theories at the interstices of anthropology and geography, to question current approaches to management based on neoclassical and neoliberal economic rationales. I present an analysis of two feral pig management regimes in Far North Queensland, Australia: (i) bounty systems of payment for feral pig control; and (ii) a community-based feral pig trapping program. I show how these management methods reshape important social and cultural processes through their overlapping technological and economic elements. On the basis of this analysis, I propose a conceptual framework for invasive animal management planning that incorporates a beneficiary–benefactor analysis alongside cost–benefit analyses. I argue that ecological-economic theories of pest management may be usefully enhanced by addressing the links between economic and social behaviours.  相似文献   
104.
Increasing recognition of the value of practice-based or experiential knowledge in natural resource management justifies the creation of a new category of articles in Society & Natural Resources that we are calling Practice-Based Knowledge (PBK). The rationale for focusing on PBK is due to its key role in the emergence of hybrid governance institutions across state, market, and civil society, understanding the complexity of dynamic socioecological systems, recognizing the challenges of multiple knowledge systems and context-specific practices, embracing the power of informal institutions and civic science, and engaging debates on the growing prevalence of market-oriented conservation. The goal is to provide a dedicated space within the published, peer-reviewed literature for scholars, government officials, nonprofit managers, and engaged citizens to share experiences informed by practical action. Relevant and timely practice-based insights may improve understanding and management of social and ecological processes and systems, while also offering the potential to contribute to theory.  相似文献   
105.
According to the connotation and structure of science and technology resources and some relevant data of more than 286 cities at prefecture level and above during 2001–2010, using modified method—Data Envelopment Analysis(DEA), science and technology(ST) resource allocation efficiency of different cities in different periods has been figured out, which, uncovers the distributional difference and change law of ST resource allocation efficiency from the time-space dimension. Based on that, this paper has analyzed and discussed the spatial distribution pattern and evolution trend of ST resource allocation efficiency in different cities by virtue of the Exploratory Spatial Data Analysis(ESDA). It turned out that:(1) the average of ST resource allocation efficiency in cities at prefecture level and above has always stayed at low levels, moreover, with repeated fluctuations between high and low, which shows a decreasing trend year by year. Besides, the gap between the East and the West is widening.(2) The asymmetrical distribution of ST resource allocation efficiency presents a spatial pattern of successively decreasing from Eastern China, Central China to Western China. The cities whose ST resource allocation efficiency are at higher level and high level take on a cluster distribution, which fits well with the 23 forming urban agglomerations in China.(3) The coupling degree between ST resource allocation efficiency and economic environment assumes a certain positive correlation, but not completely the same. The differentiation of ST resource allocation efficiency is common in regional development, whose existence and evolution are directly or indirectly influenced by and regarded as the reflection of many elements, such as geographical location, the natural endowment and environment of ST resources and so on.(4) In the perspective of the evolution of spatial structure, ST resource allocation efficiency of the cities at prefecture level and above shows a notable spatial autocorrelation, which in every period presents a positive correlation. The spatial distribution of ST resource allocation efficiency in neighboring cities seems to be similar in group, which tends to escalate stepwise. Meanwhile, the whole differentiation of geographical space has a diminishing tendency.(5) Viewed from LISA agglomeration map ofST resource allocation efficiency in different periods, four agglomeration types have changed differently in spatial location and the range of spatial agglomeration. And the continuity of ST resource allocation efficiency in geographical space is gradually increasing.  相似文献   
106.
Dr. David Mark is widely regarded as a path-breaking researcher in geographic information science. What are the structural and temporal characteristics of his intellectual contributions, as seen through the eyes of the broader academic community? Aiming to answer that question, this article presents a scientometric analysis of publications that have been cited alongside David Mark’s papers. In deliberate contrast to the widespread focus on using citation data to condense scientific impact into a handful of indicators, the methodological contribution of this study lies in its mix of computational and visualization approaches. In the search for latent domain structures, state-of-the-art practices in information science, bibliometrics, and network visualization are combined and extended. An initial network of 50,000+ publications and 4,000,000+ document co-citations undergoes a series of transformations reducing it to 9000 publications that are then clustered in a two-stage process, leading to 678 communities whose co-citation linkages are used to delineate 19 super-communities. To enable replication of this approach for other studies, much focus in this article is on detailed discussion of that workflow as well as on highlighting the reasoning behind the choices made among data sources and analytical methods. The topical evolution of David Mark’s domain of influence is explored in some detail, based on tabular and graphic representations of extracted community structures. Results confirm not only the enormous overall breadth of his influence but also how lasting and recurrent it has been in some areas.  相似文献   
107.
基于指标规范值的海水水质评价的SVR模型   总被引:1,自引:0,他引:1  
为了建立具有普适通用的海水水质评价的支持向量机模型,在设置各指标参照值和指标规范变换式,并对指标进行规范变换的基础上,应用免疫进化优化算法,建立基于指标规范值的海水水质评价的回归支持向量机模型。将优化好的模型用于珠江口海水水质的评价,其评价结果与BP神经网络的评价结果基本一致,从而表明基于指标规范值的支持向量机模型用于海水水质评价是可行的,且该模型较传统的支持向量机评价模型具有较好的普适性和通用性。  相似文献   
108.
运用气象影视节目强化气象科普宣传   总被引:1,自引:0,他引:1  
通过对目前气象科普知识宣传现状的分析,找出存在的问题和电视气象节目气象科普宣传的优势,提出强化电视气象节目气象科普宣传的建议,为我们搞好气象科技服务打下良好的社会基础.  相似文献   
109.
单体分子放射性碳同位素分析(CSRA)是近十几年来发展起来的一项新兴的分析手段,将所需的单体分子(生物标志物)从复杂的环境样品基质中分离并富集,再进行加速质谱仪(AMS)的放射性碳(14C)测定。这种分子水平的放射性碳同位素测定技术能够揭示出总有机质同位素组成的异质性,为解释有机碳的来源、迁移和转化等提供了新型的手段。在海洋科学研究中,单体分子放射性碳同位素分析已应用于计算碳在全球各储库的逗留时间并揭示和定量估算化石源有机碳的输入、指示沉积物的搬运过程、示踪微生物的代谢途径、改进沉积物年代学等;在环境科学研究中,单体分子放射性碳同位素分析可用于有毒物质(如多环芳烃)的源解析,示踪有机污染环境中微生物的代谢途径等。伴随着单体分子分离技术的改进及AMS灵敏度的提高,CSRA技术的应用会更加广泛。  相似文献   
110.
随着5G/6G、云计算、物联网和人工智能等新技术的发展,人类已经进入了万物互联时代。本文探讨万物互联时代地球空间信息技术的五大特点:定位技术从GNSS和地面测量走向无所不在的定位导航定时(PNT)服务体系;遥感技术从孤立的遥感卫星走向空天地传感网络;地理信息服务从地图数据库为主走向真三维实景和数字孪生;3S集成从移动测量发展到智能机器人服务;学科研究范围从对地观测走向物联监测和对人类活动的感知。笔者基于这些特点进一步剖析新时代面临的挑战,并提出新时代地球空间信息学发展亟待解决的三大科学技术问题:测绘学科如何服务人与机器人的共同需求?遥感影像解译的机理是什么和如何突破实现技术的瓶颈?如何利用时空大数据挖掘人与自然的关系,从空间感知走向空间认知?万物互联时代的地球空间信息学,必须且完全可能为万物互联的数字地球和智慧社会做出更大的贡献!  相似文献   
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