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111.
《Marine Policy》2015
When the development of marine renewable energy (MRE) is only possible inside already established marine protected areas (MPAs), and there is a risk of ecosystem loss, environmental or monetary compensation -being the last step in a hierarchy of mitigation measures- might be an option for working out a trade-off between energy production and nature protection. In this article, it is argued that for this type of siting situation, instead of the well-established strategy of no net loss, a net gain should be provided from the MRE developer to the MPA manager, which acts as an incentive for the manager to cooperate and covers future potentially lost conservation benefits due to MRE potential damages. Based on this argument, a hypothetical example is used to demonstrate that a net gain is ensured only when there is a societal surplus from a combined MRE-MPA arrangement that can be divided between the players through bargaining. However, when asymmetric information is involved, it is shown that cooperative solution concepts are more sufficient for leaving both players better off after coexistence than before. 相似文献
112.
基于ObjectARX.Net的Jig技术及其应用研究 总被引:2,自引:0,他引:2
论述了通过继承DrawJig类的所有方法、过程和事件,重载Sampler和WorldDraw函数,实现用户定制CAD互动命令的步骤和方法。详细介绍了动态坐标标注实例,通过DrawJig类控制拖动序列接受用户的选定坐标点,从而确定坐标标注各要素的标注位置,最后采用AddEntity函数向CAD数据库添加实体对象的方法实现了数字化成图软件中的动态标注功能。 相似文献
113.
Yong Ge Xitao Xing Qiuming Cheng 《International Journal of Applied Earth Observation and Geoinformation》2010
Society relies greatly upon infrastructure networks that are highly interconnected and mutually dependent in complex ways. Simulation and modeling assist in dealing with the complexity of infrastructure networks, especially in the effective response and management of resources for rescue, recovery, and restoration. This paper introduces the Petri net into a geographical information system to develop the GeoPetri Net system, which can be used to simulate the complex geographical relationships among places and nodes. Unlike the ordinary Petri net, the GeoPetri Net deals with places and nodes with geographical locations and the geographical relationships between these nodes and records the statuses of nodes to produce simulated events. A case study involving an education layer with 15 nodes (schools) and a transportation layer with 25 node lines (streets) in a geographical information system is presented to substantiate the above conceptual arguments. 相似文献
114.
115.
智能客户端模式的数据共享系统构建——以湖泊-流域数据共享系统为例 总被引:1,自引:0,他引:1
智能客户端是易于部署和管理的客户端应用程序。它综合了B/S架构和C/S架构的优点,在许多领域有广泛的应用前景。本文分析了智能客户端模式在数据共享系统中应用的可行性,并通过其在湖泊-流域数据共享系统的成功应用,最终表明智能客户端模式在数据共享领域有很多优势,具有推广的价值。文章还针对目前数据共享系统的功能,提出了在智能客户端模式下实现开发数据共享系统的方法和步骤。 相似文献
116.
Experiments on surface aquaponics were carried out in simulatedly-eutrophicated cement ponds with the concentrations ofkjeldahl nitrogen (KN) 2.084 mg·l-1 and TP 0.248 mg·l-1 and without any interference from natural environment factors. On the surface of ponds rice was planted on floating-beds without soil for the purpose of collecting nutrients (N & P) from water by absorption and adsorption of rice roots. The results show that the design is not only feasible but also very effective. When the coverage of rice on floating-beds were 20%, 40% and 60%, respectively with the water depth of about 1.4 m, the removal rates of KN in water reached 29.0%, 49.8% and 58.7%, respectively and those of TP 32.1%, 42.0% and 49.1%, respectively during the test period of 84 days from tillering to maturing of rice. Other main parameters of water quality were greatly improved. The results provided a scientific basis for surface aquaponics engineering to purify eutrophicated water bodies by planting terrestrial higher plants on floating-beds. 相似文献
117.
提出以无人机季节航拍影像为数据源,采用ENVI5.3软件中的CART方法对广西北部湾的典型岛群红树林景观类型进行解译,借助于Python语言实现CASA模型并将其引入到对岛群红树林生态系统的研究中,得出了不同海岛和红树林生态系统净初级生产力(NPP)的空间分布特征。结果表明:1)可见光波段差异性植被指数(VDVI)可以很好地区分海岛及红树林植被等典型地物,可应用在岛群红树林生态系统NPP的估算上;2)研究区NPP的总量为127.09 t·C/a,NPP的年均碳密度值介于0~1 437.12 g·C/m2,年均碳密度为399.85 g·C/m2。红树林生态系统的NPP值较高,而海岛生态系统的NPP值较低;3)季节尺度上NPP碳密度的大小与年内太阳辐射有直接的关系,夏季的NPP碳密度最大,冬季最小;4)白骨壤的单位面积NPP最大,为1 123.09 g·C/m2,而桐花树最小,为649.65 g·C/m2。红树林生态系统NPP平均碳密度低于实测样地和深圳福田红树林计算结果,这与不同红树林群落的植被光谱特征有关。 相似文献
118.
119.
Geographical and seasonal variations in biomass and estimated production rates of net zooplankton in Yatsushiro Bay, Japan 总被引:1,自引:1,他引:0
The biomass and production rate of net zooplankton were studied at eight stations in Yatsushiro Bay, Japan, monthly from May
2002 to April 2003. Based on environmental conditions, the bay was divided into three regions, viz. northern (average depth,
salinity and chlorophyll a concentration: 11 m, 31.8 and 6.5 μg l−1, respectively), central (30 m, 32.8 and 3.2 μg l−1, respectively) and southern (43 m, 33.4 and 1.9 μg l−1, respectively). Net zooplankton biomass was high in warm months and low in cold ones, with annual averages of 20.2, 38.8
and 16.4 mg C m−3 in the northern, central and southern regions, respectively. Copepods were the most important constituent (>ca. 70% of net
zooplankton biomass) in all regions. The northern region was characterized by the dominance of Oithona spp. in summer and Acartia spp. in winter-spring. In the central region, Microsetella norvegica was most pronounced in summer-fall. In both central and southern regions, Calanus sinicus and Eucalanus spp. dominated in winter-spring and fall, respectively. The annual average net zooplankton secondary production rate was
4.4, 7.5 and 3.9 mg C m−3d−1 in the northern, central and southern region, respectively. Combining the results from the present study with those from
other collaborative works on microzooplankton allowed us to determine the trophic interactions in Yatsushiro Bay. If the secondary
producers depend entirely on phytoplankton for food, their daily carbon requirement is equivalent to 12.5, 21.6 and 19.1%
of the phytoplankton biomass in the respective regions. 相似文献
120.
地气系统净辐射加热的季节变化及其与亚洲夏季风的关系 总被引:2,自引:1,他引:2
利用卫星观测的外逸长波辐射(OLR)资料、大气层顶短波净辐射(SHT)资料以及美国国家环境预报中心(NCEP)的环流资料,分析了地气系统净辐射加热(QRT)的季节性演变及其与亚洲夏季风的关系。结果表明,QRT的纬向偏差(QRTD)反映了海陆间的热力差异,QRTD随着季节的变化,海陆之间存在突变性反向,由春季到夏季,这种季节性反向要比大气环流的突变早一个月,它可能是导致亚洲夏季风建立和撤退的关键因素。 相似文献