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1.
Natural Resource Management (NRM) is often conducted as a partnership between government and citizens. In Australia, government agencies formulate policy and fund implementation that may be delivered on-ground by community groups (such as Landcare). Since the late 1980s, over AUS$8b of Commonwealth investment has been made in NRM. However, quantitative evidence of environmental improvements is lacking. The NRM Planning Portal has been developed to (1) provide an online spatial information system for sharing Landcare and agency data; and (2) to facilitate NRM priority setting at local and regional planning scales. While the project successfully federates Landcare NRM activity data, challenges included (1) unstructured, non-standardized data, meaning that quantitative reporting against strategic objectives is not currently possible, and (2) a lack of common understanding about the value proposition for adopting the portal approach. Demonstrating the benefit of technology adoption is a key lesson for digital NRM planning.  相似文献   
2.
We review some issues relevant to volatile element chemistry during accretion of the Earth with an emphasis on historical development of ideas during the past century and on issues we think are important. These ideas and issues include the following: (1) whether or not the Earth accreted hot and the geochemical evidence for high temperatures during its formation, (2) some chemical consequences of the Earth’s formation before dissipation of solar nebular gas, (3) the building blocks of the Earth, (4) the composition of the Earth and its lithophile volatility trend, (5) chemistry of silicate vapor and steam atmospheres during Earth’s formation, (6) vapor - melt partitioning and possible loss of volatile elements, (7) insights from hot rocky extrasolar planets. We include tabulated chemical kinetic data for high-temperature elementary reactions in silicate vapor and steam atmospheres. We finish with a summary of the known and unknown issues along with suggestions for future work.  相似文献   
3.
孙鸿烈  石玉林  李文华  封志明  江东 《地理学报》2020,75(12):2610-2619
中华人民共和国成立以来,中国的资源科学研究在自然资源考察的基础上形成了一门综合性的学科体系。本文系统总结中国资源科学从自然资源综合考察到资源科学综合研究的发展历程,大致可划分为自然资源综合考察初期(20世纪50—60年代)、区域资源综合科学考察与资源科学研究时期(20世纪70—80年代)、资源科学学科体系的形成与发展时期(20世纪90年代—2000年)及现代资源科学迈向新发展时期(21世纪以来)等4个阶段,促进了中国自然资源的考察和开发利用事业不断向前发展,对中国资源科学形成与发展影响深远。当下面向生态文明建设和美丽中国建设两个国家先进发展需求,资源科学研究要以史为鉴,推陈出新,不断丰富学科的新概念、新知识与新方法,促进资源科学的蓬勃发展。  相似文献   
4.
祁连山是中国西部重要生态安全屏障,是国家重点生态功能区,其生态保护与治理一直受到国家、地方政府和当地居民高度关注。目前,在祁连山的生态保护工作中,缺乏对现状基础数据的全面掌握,区域经济发展与生态环境保护矛盾突出,生态环境综合监测系统不完备,生态补偿机制推进实施缺乏创新。在全面梳理祁连山目前存在的重大生态问题的基础上,提出了祁连山生态保护红线落地并严守的建议,包括加快开展祁连山综合科学考察、完善并落实开展生态补偿机制、探索以正面清单为导向的协调发展模式、促进生态安全与地方经济社会可持续发展相协调、进一步实施重大配套政策、完善保障支撑体系等。  相似文献   
5.
鉴于北极特殊的地理位置和自然环境,北极科技外交往往是各国参与北极事务的起点和实现北极利益的先导。中国也概不能外,北极科技外交对保障北极科研装备、提高北极认识水平和促进北极资源开发等都具有重要意义。回溯中国参与北极事务的历程,北极科技外交是其中的主要线索和核心内容,现已取得了一些成绩。但作为域外国家和发展中国家,中国北极科技外交还面临着缺乏顶层设计、政策和资金支持不足以及若干国际因素的掣肘。对此,中国应通过充分发挥政府的主导作用、强化和完善运行机制、扩展北极科技外交的广度和深度等加以改进。  相似文献   
6.
Coffee berry necrosis is a fungal disease that, at a high level, significantly affects coffee productivity. With the advent of surface mapping satellites, it was possible to obtain information about the spectral signature of the crop on a time scale pertinent to the monitoring and detection of plant phenological changes. The objective of this paper was to define the best machine learning algorithm that is able to classify the incidence CBN as a function of Landsat 8 OLI images in different atmospheric correction methods. Landsat 8 OLI images were acquired at the dates closest to sampling anthracnose field data at three times corresponding to grain filling period and were submitted to atmospheric corrections by DOS, ATCOR, and 6SV methods. The images classified by the algorithms of machine learning, Random Forest, Multilayer Perceptron and Naive Bayes were tested 30 times in random sampling. Given the overall accuracy of each test, the algorithms were evaluated using the Friedman and Nemenyi tests to identify the statistical difference in the treatments. The obtained results indicated that the overall accuracy and the balanced accuracy index were on an average around 0.55 and 0.45, respectively, for the Naive Bayes and Multilayer Perceptron algorithms in the ATCOR atmospheric correction. According to the Friedman and Nemenyi tests, both algorithms were defined as the best classifiers. These results demonstrate that Landsat 8 OLI images were able to identify an incidence of the coffee berry necrosis by means of machine learning techniques, a fact that cannot be observed by the Pearson correlation.  相似文献   
7.
300 BC-1900 AD无定河流域城镇时空格局演变   总被引:2,自引:1,他引:1  
佟彪  党安荣  许剑 《地理学报》2019,74(8):1508-1524
通过分析和整理从战国中晚期(约300 BC)至清末(约1900 AD)无定河流域历代县级及以上城址的位置、兴废年代数据,结合行政区划沿革、经济社会发展、政权更迭等资料,分析流域城镇格局的时空演变过程。研究表明:① 受气候周期性波动影响,无定河流域城镇的兴起与衰废具有明显的周期性特征,城镇几何中心的移动轨迹具有明显的“西北—东南”向潮汐性运动特征;② 城址存续年限普遍较短,具有明显的阶段性特征,流域内曾存在过4个阶段性中心城镇,中心城镇移动的方向和过程与城镇几何中心的潮汐性移动过程趋势一致;③ 流域城镇空间格局可分为3种类型,即秦汉与隋唐时期的沿河流谷地分布,宋、明两代的沿边境线与长城分布,以及元、清两代集中于流域下游分布。流域城镇未来的发展布局应重视气候变化对城镇分布的长期影响,关注区域环境的脆弱性,合理安排城镇体系发展规模与布局。  相似文献   
8.
王凡  孙松 《海洋与湖沼》2020,51(4):664-672
中国科学院海洋研究所是新中国第一个专门从事海洋科学研究的国立科研机构,她的70年光辉历程是我国海洋科技事业从无到有、从弱到强的发展缩影,是新中国海洋科学调查研究自主创新发展历程的真实写照。本文简要介绍中国科学院海洋研究所的主要发展历程,回顾70年来取得的主要科技成就,并围绕新形势下建设海洋大科学研究中心等改革发展举措,讨论和展望研究所的未来发展。  相似文献   
9.
An in-depth analysis of the urban road network structure plays an essential role in understanding the distribution of urban functional area. To concentrate topologically densely connected road segments, communities of urban roads provide a new perspective to study the structure of the network. In this study, based on OpenStreetMap (OSM) roads and points-of-interest (POI) data, we employ the Infomap community detection algorithm to identify the hierarchical community in city roads and explore the shaping role roads play in urban space and their relation with the distribution of urban functional areas. The results demonstrate that the distribution of communities at different levels in Guangzhou, China reflects the urban spatial relation between the suburbs and urban centers and within urban centers. Moreover, the study explored the functional area characteristics at the community scale and identified the distribution of various functional areas. Owing to the structure information contained in the identification process, the detected community can be used as a basic unit in other urban studies. In general, with the community-based network, this study proposes a novel method of combining city roads with urban space and functional zones, providing necessary data support and academic guidance for government and urban planners.  相似文献   
10.
Crowd-based hydrological observations can supplement existing monitoring networks and allow data collection in regions where otherwise no data would be available. In the citizen science project CrowdWater, repeated water level observations using a virtual staff gauge approach result in time series of water level classes (WL-classes). To investigate the quality of these observations, we compared the WL-class data with “real” (i.e., measured) water levels from the same stream at a nearby gauging station. We did this for nine locations where citizen scientists reported multiple observations using a smartphone app and at 12 locations where signposts were set up to ask citizens to record observations on a paper form that could be left in a letterbox. The results indicate that the quality of the data collected with the app was better than for the forms. A possible explanation is that for each app location, a single person submitted the vast majority of the observations, whereas at the locations of the forms almost every observation was made by a different person. On average, there were more contributions between May and September than during the other months. Observations were submitted for a range of flow conditions, with a higher fraction of high flow observations for the locations were data were collected with the app. Overall, the results are encouraging for citizen science approaches in hydrology and demonstrate that the smartphone application and the virtual staff gauge are a promising approach for crowd-based water level class observations.  相似文献   
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