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61.
基于CITYgreen模型的城市森林管理信息系统的构建与应用   总被引:20,自引:2,他引:18  
通过Arcview3.2开发语言Avenue,建立了基于CITYgreen模型的城市森林管理信息系统,为城市森林结构研究、生态效益综合评价提供了理论与技术依据,并利用该系统对沈阳市区城市森林进行了结构分析和生态效益定量评价。  相似文献   
62.
Although fungal spores are an ever-present component of the atmosphere throughout the year, their concentration oscillates widely. This work aims to establish correlations between fungal spore concentrations in Porto and Amares and meteorological data. The seasonal distribution of fungal spores was studied continuously (2005–2007) using volumetric spore traps. To determine the effect of meteorological factors (temperature, relative humidity and rainfall) on spore concentration, the Spearman rank correlation test was used. In both locations, the most abundant fungal spores were Cladosporium, Agaricus, Agrocybe, Alternaria and Aspergillus/Penicillium, the highest concentrations being found during summer and autumn. In the present study, with the exception of Coprinus and Pleospora, spore concentrations were higher in the rural area than in the urban location. Among the selected spore types, spring-autumn spores (Coprinus, Didymella, Leptosphaeria and Pleospora) exhibited negative correlations with temperature and positive correlations both with relative humidity and rainfall level. On the contrary, late spring-early summer (Smuts) and summer spores (Alternaria, Cladosporium, Epicoccum, Ganoderma, Stemphylium and Ustilago) exhibited positive correlations with temperature and negative correlations both with relative humidity and rainfall level. Rust, a frequent spore type during summer, had a positive correlation with temperature. Aspergillus/Penicillium, showed no correlation with the meteorological factors analysed. This knowledge can be useful for agriculture, allowing more efficient and reliable application of pesticides, and for human health, by improving the diagnosis and treatment of respiratory allergic disease.  相似文献   
63.
连续年龄序列桉树人工林凋落物量及养分通量   总被引:1,自引:0,他引:1  
在福建漳州地区,对连续年龄序列(2、3、4、5、6年生)的尾巨桉(Eucalyptus grandis ×E.urophylla)人工林凋落物量及其养分通量进行了研究.结果表明:不同林龄(2、3、4、5和6年生)的年凋落物总量分别为2796.65、3098.10、4489.13、4200.72和3692.40 kg·hm-2,呈现先期增加,4年生后出现缓慢下降的趋势.各年龄段林分凋落物量均显示出明显的季节动态,其中3、4和6年生林分呈单峰型,前二者出现在6月,后者出现在4月;而2和5年生林分则出现2个峰值,前一个峰值出现在4月,后一峰值出现在6月.在凋落物的组成中,落叶占总凋落物量的84.86%~90.04%,其次分别为碎屑物(5.01%~6.70%)、落枝(2.95%~4.52%)、树皮(2.64%~3.62%)和落果(0.30%~0.55%).凋落物各组分中,主要养分元素含量大小顺序为N>Ca>K>Mg>P.各龄级桉树人工林凋落物中5种元素的年通量的大小顺序表现为:4年生(133.20 kg·hm-2)>5年生(124.98 kg·hm-2)>6年生(97.56 kg·hm-2)>3年生(90.51 kg·hm-2)>2年生(86.01 kg·hm-2).  相似文献   
64.
微生物在矿床的形成过程中起着重要的作用。本文对新疆十红滩铀矿床不同亚带容矿层中的微生物进行了分离、鉴定、计数。结果表明:容岩矿石中存在不同种类的好氧和厌氧微生物,其分布随地质特征的变化呈现明显的规律性,氧化带微生物种类和数量较多,好氧的铁细菌为其中的优势菌群;氧化-还原过渡带好氧菌与厌氧菌共存,但好氧菌种类有所减少;还原带中主要的微生物类群为厌氧的硫酸盐还原菌。研究结果对于指导铀矿的开采技术、铀污染治理等有重要意义。  相似文献   
65.
Urban habitats harbour considerable biological diversity. Ecologists have developed methods to select which habitats should be conserved. The Ecological value, a method based on vegetation, has been created for the urban habitats of Montreal (Quebec, Canada). The main objective of our study was to determine if this method was relevant to assess carabid diversity of Mount Royal Park. This index is calculated using five criteria: uniqueness, representativeness, degree of succession, richness and rarity of the flora, each of which can influence communities of insects. Ground beetles (Coleoptera: Carabidae) were selected because of their success as biological indicators. Despite sampling difficulties, our results demonstrate clearly that the Ecological value method does not represent the high carabid richness of urban open habitats (tall grasses) and their specialised native carabid species. Within forests we found nonetheless that the ecological value index has a significant positive relationship with native carabid abundance. Moreover, maturity and structure of urban forests were positively correlated with carabid abundance and richness. Some urban vegetation characteristics have been shown to influence entomological diversity, but the relevance of using a global floral index to encompass the carabid community seems limited.  相似文献   
66.
Psychological stress and environmental pollution are frequently associated to urban environment and oxidative stress (OxS). Likewise, OxS is a risk factor for cognitive impairment (CI) in the elderly. Therefore, we hypothesized that the prevalence of CI in subjects of the urban area could be higher than in those of the rural area, and linked to higher OxS. The aim of the study was to determine the relationship between OxS and CI in elderly individuals from rural and urban settings in Mexico. Plasmatic TBARS, plasma total antioxidant status, and the antioxidant enzymes superoxide dismutase (SOD) and glutathione peroxidase (GPx) were measured in 104 urban and 85 rural elderly individuals. Cognitive functions were evaluated through the Mini Mental State Examination. We found a greater proportion of subjects with OxS and CI in urban than in rural areas (25% vs. 9%), with an odds ratio of 5.67 (CI95% 1.14-38.02, p < 0.05). Our findings suggest that the elderly in urban areas have more OxS and a higher risk of developing CI compared with elderly individuals in a rural environment.  相似文献   
67.
城市生活垃圾堆肥发酵中微生物菌群变化规律的研究   总被引:1,自引:0,他引:1  
通过对垃圾处理厂静态堆肥不同区域的微生物菌群与数量的分析,表明了城市生活垃圾堆肥发酵中微生物菌群的变化规律,温度与微生物菌群的相关性,指出了高温微生物菌群数量影响堆肥的效率。建议在静态一次堆肥发酵周期中,增加通气量和翻堆频率,有利于增强微生物菌群的活力和提高堆肥质量。  相似文献   
68.
采用Heath-Carter人体测量法对江西城市客家人304例(男154例,女150例)进行了体型评定。结果显示:1)江西城市客家人男性平均体型值为4.0-4.6-2.0,属于偏内胚层的中胚层体型;女性平均体型值为5.0-4.2-1.9,属于偏中胚层的内胚层体型。2)男女均以30岁为体型分界点,表现为30岁前后的体型差异。3)60岁前男女体型存在显著性差异。60岁后男女体型没有差异。4)与国内其他城市汉族比较,城市客家人男性平均体型点与内蒙古汉族最近,女性与云南汉族最为接近。客家人男女体型较其他城市汉族纤瘦,身体的线性度较高。  相似文献   
69.
This study compared different measures of urban heat island (UHI) intensity, which were calculated using both air temperature (Tair) at a height of 1.5 m and Landsat land surface temperature (LST) in Hangzhou, China. Two UHI-driven indicators (range and magnitude) and two land-cover-driven indicators (urban-rural and urban-agriculture) were calculated to quantify the UHI intensity based on hourly Tair from five stations and fifteen Landsat 5 LST images. Pearson correlation testing and a moving average times series of the previous 30 days were used to investigate the relationship between UHI intensities calculated by different indicators and data. The results indicate that the land-cover-driven indicators explain UHI better than the UHI-driven indicators, while the calculated values of UHI intensity using Landsat LST and hourly Tair are not comparable. We also investigated the influence of weather conditions on UHI intensity. Generally, Landsat-LST-based UHI performs best on hot sunny days, while Tair-based UHI has a better chance during the nighttime following a dry sunny day. This study suggests that the value of UHI intensity can be influenced by the selected indicators, the data used, the acquisition time and the weather conditions. Thus, these factors should be considered when comparing UHI intensity between different cities or quantifying their influences (e.g., population size, land use and land cover change) on UHI intensity.  相似文献   
70.
Many modern cities have strongly invested in the sustainability of their urban water management system. Nordic cities like Stockholm or Copenhagen are amongst pioneers in investments towards integrated urban water management. However, cities can never be fully self-sufficient due to their dependency on external (water) resources. In this paper, we quantify this water dependency with respect to food consumption in nine cities located in the five Nordic countries (Sweden, Denmark, Finland, Norway and Iceland), by means of the water footprint concept. Detailed urban water footprint assessments are scarce in the literature. By analysing national nutrition surveys, we find that urban food intake behaviour differs from national food intake behaviour. In large Nordic cities people eat generally less potatoes, milk products (without cheese), meat and animal fats and they drink less coffee than outside city borders. On the other hand, they generally eat more vegetables and vegetable oils and they drink more tea and alcoholic beverages. This leads consistently – for the six large Nordic cities Stockholm, Malmö, Copenhagen, Helsinki, Oslo and Reykjavik – to slightly smaller food related urban water footprints (−2 to −6%) than national average values. We also analyse the water footprint for different diets based upon Nordic Nutrition Recommendations (NNR) for these cities. We assessed three healthy diet scenarios: 1) including meat (HEALTHY-MEAT), 2) pesco-vegetarian (HEALTHY-PESCO-VEG) and 3) vegetarian (HEALTHY-VEG). This shows that Nordic urban dwellers 1) eat too many animal products (red meat, milk and milk products) and sugar and drink too much alcohol and 2) they eat not enough vegetables, fruit and products from the group pulses, nuts and oilcrops. Their overall energy and protein intake is too high. A shift to a healthy diet with recommended energy and protein intake reduces the urban WF related to food consumption substantially. A shift to HEALTHY-MEAT results in a reduction of −9 to −24%, for HEALTHY-PESCO-VEG the reduction is −29 to −37%, for HEALTHY-VEG the reduction is −36 to −44%. In other words, Nordic urban dwellers can save a lot of water by shifting to a healthy diet.  相似文献   
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