峡谷廊道景观: 区域自然景观和文化景观的全面挖掘——大连十八盘“海底大峡谷”规划建设研究

大连十八盘海底大峡谷景观从2001年开始修建,在地域景观延续性设计的创作理念指引下,运用工程技术手段对裸露的岩壁进行处理,使景观在现实生活与艺术美的高度统一等方面进行积极的探索。夸张的海洋生物雕塑占据景观主导地位。通过对景区的描述,分析其区域角色地位,阐明建设理念,详述裸岩治理的建设内容。     

The distribution of a threatened migratory bird species in a patchy landscape: a multi-scale analysis

Understanding the driving forces behind the distribution of threatened species is critical to set priorities for conservation measures and spatial planning. We examined the distribution of a globally threatened bird, the corncrake (Crex crex), in the lowland floodplains of the Rhine River, which provide an important breeding habitat for the species. We related corncrake distribution to landscape characteristics (area, shape, texture, diversity) at three spatial scales: distinct floodplain units (“floodplain scale”), circular zones around individual observations (“home range scale”), and individual patches (“patch scale”) using logistic regression. Potential intrinsic spatial patterns in the corncrake data were accounted for by including geographic coordinates and an autocovariate as predictors in the regression analysis. The autocovariate was the most important predictor of corncrake occurrence, probably reflecting the strong conspecific attraction that is characteristic of the species. Significant landscape predictors mainly pertained to area characteristics at the patch scale and the home range scale; the probability of corncrake occurrence increased with potential habitat area, patch area, and nature reserve area. The median potential habitat patch size associated with corncrake occurrence was 11.3 ha; 90% of the corncrake records were associated with patches at least 2.2 ha in size. These results indicate that the corncrake is an area-sensitive species, possibly governed by the males’ tendency to reside near other males while maintaining distinct territories. Our results imply that corncrake habitat conservation schemes should focus on the preservation of sufficient potential habitat area and that existing management measures, like delayed mowing, should be implemented in relatively large, preferably contiguous areas.     

Continuity and discontinuity of the riparian vegetation along a fluvial corridor

The concept of continuity/discontinuity is applied to the riparian vegetation of the corridor of the River Adour (S.W. France), in order to precisely define longitudinal structure, and to test the degree of floristic continuity of the fluvial axis. The measure of floristic connectance along the river course is based on presence/absence data, and is applied to successive stretches of the river, at various resolution levels. This analysis shows that the River Adour corridor cannot be assumed to be floristically continuous. The observed discontinuities may correspond to two types of change in the riparian vegetation: zones of slow change (high level of floristic connectance) or zones of sharp change (low level of floristic connectance).     

The effects of a vegetational corridor on the abundance and dispersal of insect biodiversity within a northern California organic vineyard

During 1996 and 1997, two adjacent 2.5 has organic vineyard blocks (A and B) were monitored to assess the distributional and abundance patterns of the Western grape leafhopper Erythroneura elegantula Osborn (Homoptera: Cicadellidae) and its parasitoid Anagrus epos Girault (Hymenoptera: Mymaridae), Western flower thrips Frankliniella occidentalis (Pergande) and generalist predators. The main difference between blocks was that block A was cut across by a corridor composed of 65 flowering plant species which was connected to the surrounding riparian habitat, whereas block B had no plant corridor. In both years, leafhopper adults and nymphs and thrips tended to be more numerous in the middle rows of block A and less abundant in border rows close to the forest and corridor where predators were more abundant. The complex of predators circulating through the corridor moved to the adjacent vine rows and exerted a regulatory impact on herbivores present in such rows. In block B all insects were evenly distributed over the field, no obvious density gradient was detected from the edges into the center of the field. Although it is suspected that A. epos depended on food resources of the corridor, it did not display a gradient from this rich flowering area into the middle of the field. Likewise no differences in rates of egg parasitism of leafhoppers could be detected in vines near the corridor or in the vineyard center. The presence of riparian habitats enhanced predator colonization and abundance on adjacent vineyards, although this influence was limited by the distance to which natural enemies dispersed into the vineyard. However, the corridor amplified this influence by enhancing timely circulation and dispersal movement of predators into the center of the field.     

The impact of thematic resolution on the patch-mosaic model of natural landscapes

We argue that thematic resolution, i.e., the level of categorical detail of a thematic map expressed by the number of classes included in the map legend, is an inherent component of the scale at which a landscape is analyzed. Changing the number of classes can change the configuration of the patch mosaic as much as changing the grain does. We address recent calls in this and other journals to deepen research in this topic. In particular, we report how thematic resolution affects the patchiness of mosaics representing natural landscapes, which have seldom been studied in this respect. We selected seven 50 × 50 km landscapes within national parks, each representative of a world biome. We applied an object-based unsupervised classification to Landsat TM imagery of these landscapes using increasing numbers of classes, between 2 and 50, and derived curves of mean patch size and patch density for each site. Our results are consistent with previous findings in that the patchiness of output mosaics increases monotonically with increasing thematic resolution, with a higher rate of increase up to eight classes that declines until it becomes roughly constant for more than 16 classes. However, this constant rate of increase is still considerable, meaning that, at least for natural landscapes, there is no threshold beyond which the patch-mosaic model is independent of the conceptual filter applied. This dependence on human fiat calls for re-thinking the patch-mosaic paradigm.     

Landscape-scale modelling of agroforestry ecosystems services in Swiss orchards: a methodological approach

Context

Agroforestry systems in temperate Europe are known to provide both, provisioning and regulating ecosystem services (ES). Yet, it is poorly understood how these systems affect ES provision at a landscape scale in contrast to agricultural practises.

Objectives

This study aimed at developing a novel, spatially explicit model to assess and quantify bundles of provisioning and regulating ES provided by landscapes with and without agroforestry systems and to test the hypothesis that agroforestry landscapes provide higher amounts of regulating ES than landscapes dominated by monocropping.

Methods

Focussing on ES that are relevant for agroforestry and agricultural practices, we selected six provisioning and regulating ES—“biomass production”, “groundwater recharge”, “nutrient retention”, “soil preservation”, “carbon storage”, “habitat and gene pool protection”. Algorithms for quantifying these services were identified, tested, adapted, and applied in a traditional cherry orchard landscape in Switzerland, as a case study. Eight landscape test sites of 1 km?×?1 km, four dominated by agroforestry and four dominated by agriculture, were mapped and used as baseline for the model.

Results

We found that the provisioning ES, namely the annual biomass yield, was higher in landscape test sites with agriculture, while the regulating ES were better represented in landscape test sites with agroforestry. The differences were found to be statistically significant for the indicators annual biomass yield, groundwater recharge rate, nitrate leaching, annual carbon sequestration, flowering resources, and share of semi-natural habitats.

Conclusions

This approach provides an example for spatially explicit quantification of provisioning and regulating ES and is suitable for comparing different land use scenarii at landscape scale.

     

Expression and significance of fgl2 in a model of rat coronary microthrombosis in situ

AIM: To explore the expression and significance of fibrinogen-like protein 2 prothrombinase/fibroleukin (fgl2) in a model of rat coronary microthrombosis. METHODS: Seventy-eight Sprague-Dawley male rats were randomly assigned to model group (n=36), sham operation group (n=36) for different time (1 h, 1 d, 1week, 2 weeks, 3 weeks, 4 weeks)(n=6, respectively), and normal control group (n=6). After closing aorta, sodium laurate was injected into aortic root of the animals in model group. The animals in sham operation group were injected with normal saline for control. Microthromb were detected with HE staining and modified martius-sarlet-blue stains (MMSB). von Willebrand factor (vWF) was measured with ELISA. fgl2 mRNA and protein expressions were detected by RT-PCR and immunohistochemistry staining, respectively. RESULTS: Microthromb were observed in rat coronary microvasculature. vWF was increased in plasma. fgl2 was induced in model group compared to sham operation group (P<0.05), no significant changes were observed in sham operation group and normal control group (P>0.05). CONCLUSION: The functional disorder of endothelial cells induces the expression of fgl2 in the coronary microvasculature. fgl2 prompts the thrombosis with platelet and fibrin.     

A balancing act: Biodiversity and human wellbeing considerations in the management of urban forest in a global biodiversity hotspot

Environmental and urban forest managers in cities located in highly biodiverse regions may need to balance biodiversity conservation with the provision of ecosystem services to people. However, striking this balance is not easy and many competing factors influence the decision-making process. Set in the Perth Metropolitan Area, located in the global biodiversity hotspot of the Southwestern Australia Floristic Province, this study aimed to understand: (i) the extent to which a benefits-oriented approach is used by local governments to optimise biodiversity and human wellbeing urban forest outcomes, and (ii) what other factors influence the decision-making process shaping urban forest composition. Using a social-ecological framework, we conducted semi-structured interviews with 29 local government practitioners. We found that biodiversity conservation is actively considered in the planning and management of urban forest in natural areas and parks, but rarely in streetscapes. Maximising shade and cooling, and to a lesser extent enhancing sense of place, were the key benefits actively sought in streetscapes. Parks appeared to straddle the middle ground as areas with most flexibility to accommodate multiple biodiversity and human wellbeing benefits. Yet, benefits were only some of a multitude of social-ecological factors influencing the decision-making process shaping urban forest composition. In particular, streetscapes were affected by a large number of social and political factors (e.g., perceived risk and nuisance, ad-hoc decisions by elected members), many of them leading to suboptimal urban forest outcomes. For a benefits-oriented approach to prevail in complex and contested urban spaces it is important that the decision-making process is evidence-informed and capable of handling the challenges and conflicts that are likely to arise. Reactive decision-making results in a conservative, “safe” species palette that over time defines streetscapes by what they do not do (creating disservices) rather than what they do (delivering multiple biodiversity and wellbeing benefits), which ultimately is not a desired outcome in the context of an increasingly urbanized world.     

Comparative study of flow field and drag coefficient of model and small natural trees in a wind tunnel

The influence of trees in urban areas is typically assessed using urban microclimate models. These models rely on wind tunnel experiments using small-scale tree models to verify and validate their predictions of the flow field. However, it is not known sufficiently to which extent small model trees used in wind tunnel studies can recreate the behavior of large trees found in cities. In the present study, the drag coefficient and the turbulent flow downstream of model trees are compared with the ones of natural trees of a similar size to determine whether both types of tree provide similar aerodynamic characteristics. Therefore, measurements of the drag force and the flow field, using particle image velocimetry, are performed. The aerodynamic characteristics of the small trees are compared with the ones measured on larger mature trees from previous studies. The present study shows that the drag coefficients of model and natural trees are similar only if both types have a similar aerodynamic porosity and if the model tree can undergo an aerodynamic reconfiguration similar to that of a natural tree. Such reconfiguration implies the reorientation of the branches and leaves due to wind. A study on the influence of seasonal foliar density variation shows that the foliage configuration plays a critical role on the drag coefficient and the flow field. A defoliated tree, such as a deciduous tree in winter, is shown to have a substantially lower drag coefficient and a negligible influence on the flow.     

Expression and significance of angiopoietin-2 and Tie-2 receptors in a rat model of acute lung injury

AIM: To explore the expressions and significance of angiopoietin-2 (Ang-2) and tyrosine kinase with immunoglobulin and epidermal growth factor homology domains-2 (Tie-2) receptors in a rat model of acute lung injury (ALI). METHODS: Wistar rats (n=42) were divided into control group (n=12) and cecal ligation and puncture (CLP) group (n=30). Control group underwent sham operation, and CLP group underwent cecal ligation and puncture to make the model of ALI. 12 h after sham operation or CLP, 6 rats in each group were killed, and arterial blood gas analysis and lung coefficient were tested. The expressions of Ang-2 and Tie-2 receptors in lung tissue were observed by immunohistochemical method. Blood samples of the rest rats were collected from vena caudalis, and Ang-2 levels were measured by enzyme linked immunosorbent assay (ELISA). The mortality rate in each group within 36 h was compared. The lung architecture was observed under microscope. RESULTS: The lung architecture in control group was clear and intact. Alveolar septum was thicker, blood capillary was congested, and neutrophils and macrophages were infiltrated in the lung tissue in CLP group. Tie-2 receptors were expressed in bronchial epithelial cells, smooth muscle cells and endothelial cells in control group. Besides the similar expression as control group, high expression of Tie-2 on neutrophils and macrophages in CLP group was observed. In the adhesion location of Tie-2 receptors positive inflammatory cells, there was stronger staining in endothelial cells. Ang-2 was expressed in smooth muscle cells, bronchial epithelial cells and endothelial cells in control group. The Ang-2 level in CLP group were higher than that in control group ［(8.14±1.74) μg/L vs (4.63±0.49) μg/L, P<0.01］, and the Ang-2 level of dead rats was higher than that of survival rats within 36 h in CLP group ［(8.95±1.61)μg/L vs (6.80±0.96)μg/L, P<0.01］. Oxygen partial pressure in control group was lower (P<0.01) and lung coefficient was higher (P<0.01) than that in CLP group. CONCLUSION: Ang-2 and Tie-2 receptors may participate in the pathophysiology of ALI, and Ang-2 level is correlated with mortality.     

Protocol: a highly sensitive RT-PCR method for detection and quantification of microRNAs

MicroRNAs (miRNAs) are a class of small non-coding RNAs with a critical role in development and environmental responses. Efficient and reliable detection of miRNAs is an essential step towards understanding their roles in specific cells and tissues. However, gel-based assays currently used to detect miRNAs are very limited in terms of throughput, sensitivity and specificity. Here we provide protocols for detection and quantification of miRNAs by RT-PCR. We describe an end-point and real-time looped RT-PCR procedure and demonstrate detection of miRNAs from as little as 20 pg of plant tissue total RNA and from total RNA isolated from as little as 0.1 μl of phloem sap. In addition, we have developed an alternative real-time PCR assay that can further improve specificity when detecting low abundant miRNAs. Using this assay, we have demonstrated that miRNAs are differentially expressed in the phloem sap and the surrounding vascular tissue. This method enables fast, sensitive and specific miRNA expression profiling and is suitable for facilitation of high-throughput detection and quantification of miRNA expression.     

Ultrastructural changes and significance of endometriotic rat model with HCG treatment

AIM: To investigate whether and how human chorionic gonadotropin (HCG) treatment ameliorates endometriosis in the endometriotic rat model. METHODS: The rat model of endometriosis was established and the model rats were divided into 4 groups. The rats in HCG groups were treated with 19.4, 25.8 and 51.6 IU/100 g of HCG every day (low-dose HCG, medium-dose HCG and high-dose HCG, respectively). The rats in control group were treated with 0.9% NaCl. After 15 days (3 estrous cycles), the ectopic lesion volume and ultrastructural characteristics in eutopic and ectopic endometria were investigated. RESULTS: After HCG treatment, the volume of endometriotic lesions was significantly smaller than that before treatment. Numerous and mitochondrial, endoplasmic reticulum and ribosomes were observed in the cytoplasm of eutopic and ectopic endometrium before treatment. After treatment, some cell structures were not clear, and mitochondrial cristae decreased or disappeared partly. Some cells were densed and shrinkage, autophagosome in cytoplasm increased, and mitochondria and endoplasmic reticulum swelt. CONCLUSION: HCG therapy appears to be an effective treatment for endometriosis in rats attributed to its influence on cell metabolism dysfunction of eutopic and ectopic endometria.     

The native pollinators of an apple orchard: variations and significance

Observations on native and domestic insect pollinators were carried out during the blossom period from 1978 to 1980 in a semi-dwarf apple orchard in Ontario. Weather conditions and numbers of blossoms per tree were also recorded. Apis mellifera was the most frequent pollinator for all years. The Anthomyiidae (Diptera) ranked second for 1978 and 1979, but in 1980 the Andrenidae and Halictidae were of greater importance than the Diptera. The efficiency of the pollinators was determined by analysis of the pollen carried on their bodies. Hymenoptera had more pollen on their bodies than the Diptera. Among the Hymenoptera, the Andrenidae and the pollen-gathering Large Andrenidae had the greatest amount of fruit pollen on their bodies. Among the Diptera, the Syrphidae had the greatest amount of fruit pollen. The effectiveness of the pollinators was evaluated by measuring fruit set, seed set and the effective pollination period. There was no significant difference in fruit set between years inspite of adverse weather in 1979. Native insects were important pollinators, particularly in unfavourable weather.     

Ecological impact and cost-effectiveness of wildlife crossings in a highly fragmented landscape: a multi-method approach

Landscape Ecology - Road infrastructure construction is integral to economic development, but negatively affects biodiversity. To mitigate the negative impacts of infrastructure, various types of...     

Remote Sensing in Landscape Ecology: Experiences and Perspectives in a European Context

That the relationship between remote sensing and landscape ecology is significant is due in large part to the strong spatial component within landscape ecology. However it is nevertheless necessary to have frequent overview of the interface between remote sensing and landscape ecology, particularly in the light of developments in the types of image data and techniques. The use of remote sensing within European landscape ecology provides a rich range of examples of the interface, including application of some of the latest types of image data. This paper is an overview of the interface that remote sensing has with European landscape ecology, with seven examples of the application of image data in European landscape ecology and examination of associated landscape classification issues. These examples are discussed in terms of the trends and the different roles for image data in landscape ecology that they illustrate, and in particular their classificatory and informational implications. It is suggested that with regard to classification there is a need for re-examination of the roles of image data.     

无公害胡萝卜一年双季高效栽培技术

胡萝卜属伞形花科，二年生植物。富含维生素、胡萝卜素、硫胺素、核黄素、糖类以及钙、磷、铁等微量元素，其中胡萝卜素在人体内可转化为Va，可以预防眼干症，视力衰退和夜盲症，还具有防癌、抗衰老、降低心肌梗塞与中风发病率的功效。具有很高的营养价值和保健功效。