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61.
The provision of green space is increasingly being perceived as an important factor for quality of life. However, green spaces often face high developmental pressure. The main objective of this study is to investigate a prospective approach to green space planning by combining three-dimensional (3D) visualization of green space scenarios and survey techniques to facilitate improved participation of the public. Aside from the ‘Status quo’, scenarios ‘Agriculture’, ‘Recreation’, ‘Nature conservation’ and ‘Wind turbines’ are visualized in three dimensions. In order to test responses, a survey was conducted both in print format and on the Internet. Overall, 49 different visualizations that belong to one of the scenarios were available in the survey and were rated according to the perceived esthetic, recreational and ecological values.The highest rated scenes include vegetation elements such as meadows with orchards, single trees, shrubs or forest. The least attractive scenes are those where buildings are highly dominant or where there are no vegetation elements.Based on the ratings for the individual images and on the corresponding scenarios, our study shows that there is high potential for improving the existing landscape. All suggested changes are either rated about equal to or considerably higher than the status quo, with the scenario ‘Nature conservation’ receiving the highest scores. 相似文献
62.
桫椤群落内主要乔木种群的种间联结性 总被引:7,自引:0,他引:7
张思玉 《应用与环境生物学报》2001,7(4):335-339
在相邻格子抽样调查的基础上,采用X^2检验、联结系数(Ac)和种间共出现百分率(Pc)等指标,分析了福建省永定桫椤群落内主要乔木种群的种间联结性。结果表明:除少数种对外,绝大多数种群间的联结性不显著,在联结性显著的种对中,下述7个种对之间有较高的正联结性:朴树-野鸦椿、青冈-黄瑞木、青冈-油柿、翻白叶树-拉氏栲、黄瑞木-油柿、 青冈-香叶树和Song木-盐肤木,就桫椤群落而言,桫椤与猴欢喜、水团花之间有一定的正联结,与广东润楠、黄瑞木、柳叶山 茶、朴树和野鸦椿有较紧密的负联结。图3参11 相似文献
63.
Composite sampling techniques for identifying the largest individual sample value seem to be cost effective when the composite samples are internally homogeneous. However, since it is not always possible to form homogeneous composite samples, these methods can lead to higher costs than expected. In this paper we propose a two-way composite sampling design as a way to improve on the cost effectiveness of the methods available to identify the largest individual sample value. 相似文献
64.
刘德良 《湖南环境生物职业技术学院学报》2001,7(3):60-64
园林树木栽培学是一门实践性很强的有关园林绿化领域的专业课、必修课.1995年以来,本人在园林树木栽培学各论教学中尝试重点讲解、课堂点评的教学方法,取得了较好的教学效果. 相似文献
65.
地表水体中的硝酸盐污染已经成为全球关注的热点环境问题之一。现今,国内外均建立了相关的监测网络对地表水体的水质实施长期监测,但是却导致大量的监测数据累积,给后续的科学研究工作带来了不便,尤其是在庞大的监测网络中如何选取有代表性样点的研究点则成为急需解决的问题之一。以比利时弗拉芒地区地表水的长期监测物理化学指标为例,利用决策树模型评估地表水样点的硝酸盐污染来源专家分类的有效性,为点位优化提供理论依据。原有监测点位的污染源专家分类和模型输出的可匹配率为80%,优化后监测点位从原有47个点降低到30个点,提高了监测工作效率。 相似文献
66.
Mari Luz García-Lorenzo María José Martínez-Sánchez Carmen Pérez-Sirvent Joaquín López-Sánchez José Molina-Ruiz Mari Luz Tudela 《Environmental Forensics》2015,16(1):88-95
The objective of this study was to determine the As and Sb contents in soils from the Murcia Region of Spain and the possible relationship between the mineralogical composition, soil properties, and As and Sb concentrations. In this study, 490 samples were selected from areas with different characteristics in order to study As and Sb variability. Results show that As and Sb concentrations are positively correlated with the phyllosilicate and quartz content but negatively correlated with the calcite content. The generic reference level (GRL) for these elements was determined according to the Spanish legislation. Established GRL values vary according to the established mineralogical groups, suggesting that GRL has to be determined considering the lithological characteristics of the study area. 相似文献
67.
新疆奎屯市17种落叶树种的滞尘能力研究 总被引:1,自引:0,他引:1
对奎屯市17种落叶树种进行了滞尘能力测定。结果表明,不同类型植物滞尘能力差异显著,灌木滞尘能力大于乔木。在11种落叶乔木中,滞尘能力最强的是圆冠榆,平均滞尘能力达3.6894g/m^2;在5种落叶灌木中,滞尘能力最强的是玫瑰,平均滞尘量可达3.6581g/m^2。 相似文献
68.
SallyRose Anderson Glenn Tootle Henri Grissino‐Mayer 《Journal of the American Water Resources Association》2012,48(4):849-858
Anderson, SallyRose, Glenn Tootle, and Henri Grissino‐Mayer, 2012. Reconstructions of Soil Moisture for the Upper Colorado River Basin Using Tree‐Ring Chronologies. Journal of the American Water Resources Association (JAWRA) 48(4): 849‐858. DOI: 10.1111/j.1752‐1688.2012.00651.x Abstract: Soil moisture is an important factor in the global hydrologic cycle, but existing reconstructions of historic soil moisture are limited. We used tree‐ring chronologies to reconstruct annual soil moisture in the Upper Colorado River Basin (UCRB). Gridded soil moisture data were spatially regionalized using principal components analysis and k‐nearest neighbor techniques. We correlated moisture sensitive tree‐ring chronologies in and adjacent to the UCRB with regional soil moisture and tested the relationships for temporal stability. Chronologies that were positively correlated and stable for the calibration period were retained. We used stepwise linear regression to identify the best predictor combinations for each soil moisture region. The regressions explained 42‐78% of the variability in soil moisture data. We performed reconstructions for individual soil moisture grid cells to enhance understanding of the disparity in reconstructive skill across the regions. Reconstructions that used chronologies based on ponderosa pines (Pinus ponderosa) and pinyon pines (Pinus edulis) explained more variance in the datasets. Reconstructed soil moisture data was standardized and compared with standardized reconstructed streamflow and snow water equivalent data from the same region. Soil moisture and other hydrologic variables were highly correlated, indicating reconstructions of soil moisture in the UCRB using tree‐ring chronologies successfully represent hydrologic trends. 相似文献
69.
Matsunaga SN Chatani S Nakatsuka S Kusumoto D Kubota K Utsumi Y Enoki T Tani A Hiura T 《Chemosphere》2012,87(8):886-893
Reactive volatile organic compounds (VOCs) are known to affect atmospheric chemistry. Biogenic VOCs (BVOCs) have a significant impact on regional air quality due to their large emission rates and high reactivities. Diterpenes (most particularly, kaur-16-ene) were detected in all of the 205 enclosure air samples collected over multiple seasons at two different sites from Cryptomeria japonica and Chamaecyparis obtusa trees, the dominant coniferous trees in Japan,. The emission rate of kaur-16-ene, was determined to be from 0.01 to 7.1 μg dwg−1 h−1 (average: 0.61 μg dwg−1 h−1) employing branch enclosure measurements using adsorbent sampling followed by solid phase-liquid extraction techniques. The emission rate was comparable to that of monoterpenes, which is known major BVOC emissions, collected from the same branches. In addition, total emission of kaur-16-ene at 30 °C was estimated to exceed that of total anthropogenic VOC emissions. 相似文献
70.
Jeff Joireman Heather Barnes Truelove Blythe Duell 《Journal of environmental psychology》2010,30(4):358-367
It is generally acknowledged that global warming is occurring, yet estimates of future climate change vary widely. Given this uncertainty, when asked about climate change, it is likely that people’s judgments may be affected by heuristics and accessible schemas. Three studies evaluated this proposition. Study 1 revealed a significant positive correlation between the outdoor temperature and beliefs in global warming. Study 2 showed that people were more likely to believe in global warming when they had first been primed with heat-related cognitions. Study 3 demonstrated that people were more likely to believe in global warming and more willing to pay to reduce global warming when they had first been exposed to a high vs. a low anchor for future increases in temperature. Together, results reveal that beliefs about global warming (and willingness to take actions to reduce global warming) are influenced by heuristics and accessible schemas. Several practical implications are discussed. 相似文献