Can green roofs help with stormwater floods? A geospatial planning approach

Increasing urbanization, impervious space, and the impact of climate change are threatening the future of cities. Nature-based solutions, specifically urban green infrastructures, are seen as a sustainable strategy to increase resilience against extreme weather events, including the escalating occurrence of stormwater runoff flooding. Consequently, urban planners and decision-makers have pushed their efforts toward implementing green infrastructure solutions to reduce the impact of stormwater floods. Among others, green roofs help store water and decrease stormwater runoff impacts on a local scale. This research aims to investigate the effect of surface permeability and green roof implementation on reducing stormwater flooding and subsequently provide urban planners with evidence-based geospatial planning recommendations to improve urban resilience in Helsinki. First, we modeled the current impact of stormwater flooding using the Arc-Malstrom model in Helsinki. The model was used to identify districts under high stormwater flood risk. Then, we zoomed in to a focus area and tested a combination of scenarios representing four levels of green roof implementation, two levels of green roof infiltration rates under 40-, 60-, 80-, 100 mm precipitation events on the available rooftops. We utilized open geographic data and geospatial data science principles implemented in the GIS environment to conduct this study. Our results showed that low-level implementation of green roofs with low retention rates reduces the average flood depth by only 1 %. In contrast, the maximum green roof scenario decreased most of the average flood depth (13 %) and reduced the number of vulnerable sites. The proposed methodology can be used for other cities to develop evidence-based plans for green roof implementations.     

Suitability of wood fiber substrate for production of vegetable transplants: I. Physical properties of wood fiber substrates

Several experiments were conducted with the objective to find suitable alternatives for peat substrates. Physical properties of wood fiber substrates in comparison to other organic substrates were examined. Volume weight, total pore space, pore size distribution, available water, container and air capacity, saturated hydraulic conductivity and volume loss of these substrates were determined. Wood fiber substrates showed a similar volume weight and total pore space as peat substrates, but lower water retention. Particularly the drainage performance of wood substrates results in a quick drainage of surplus water. An increase of volume weight caused a decrease of total pore space, air content and saturated hydraulic conductivity and an increase in water retention. Evaluation of these parameters under container conditions is critical since they are directly related to irrigation and therefore to plant growth. A compression of wood fiber substrates in the pots is recommended to minimize substrate loss. An increase of compression levels reduced the volume loss to almost 0 vol.%. The effect of wood fiber substrates and their volume weight on plant growth will be reported in a second paper.     

淹水胁迫及胁迫解除对甜瓜光合色素和光合特性的影响

以耐涝性差异显著的两个甜瓜品系T106 和T241 为试验材料,采用双套盆法进行淹水胁迫,研究了淹水胁迫及胁迫解除对甜瓜幼苗光合色素和光合特性的影响。结果表明：随着淹水胁迫时间的延长,2 个甜瓜品系的叶绿素a、叶绿素b、总叶绿素、类胡萝卜素含量以及净光合速率、蒸腾速率、气孔导度、胞间CO₂ 浓度均呈下降趋势,且T106 各项指标的下降幅度均低于T241;在淹水胁迫相同天数时,T106 的各项指标均高于T241;在淹水胁迫解除后,2 个甜瓜品系的各项指标均上升,且T106 的上升幅度大于T241。     

The influences of land-use changes on hydrology and riparian environment in a northern Japanese landscape

Temporal changes in a hydrological system and riparian ecosystem were examined with reference to land-use conversion in order to clarify the linkages between these two systems. First, the hydrological system of the Toikanbetsu River basin was divided into three components that measure water retention, inundation and conveyance. Variation in the hydrological system was expressed as a basis of delineating the three components and estimating their functions. The rainfall-runoff system was also examined using a model which can predict responses of surface-, subsurface- and base flows on rainfall intensity. Second, areas and fragmentation of the riparian forests, maximum stream temperature in summer and amount of coarse woody debris (CWD) were selected as parameters indicating the condition of the riparian ecosystem. Temporal changes in stream temperature and amount of CWD were estimated using multiple regression analysis and analysis of variance, respectively. The results indicated that the hydrological system has been altered since the 1970s, increasing flood peaks by 1.5–2.5 times and shortening peak appearance by 7 hours. Riparian forests have been disappearing since the 1960s due to extensive development of agricultural lands and river channelization. The summer maximum stream temperature increased from 22 °C in 1947 to 28 °C at present. The amount of CWD should substantially decrease with river channelization and associated forest cutting. Fish favoring cool water, such as masu salmon, could survive in 1947 although they are forced to migrate to cooler forested upstream tributaries now. The ecological systems were closely related to and distinctly altered by land-use. Finally, we propose a new perspective for understanding the two interrelated systems. Riparian ecosystems can be restored by restoring water retention and inundation functions, which also reduce the flood hazard generated by elevated flood peaks.     

Simulating the effects of climate change on population connectivity of American marten (Martes americana) in the northern Rocky Mountains, USA

We utilize empirically derived estimates of landscape resistance to assess current landscape connectivity of American marten (Martes americana) in the northern Rocky Mountains, USA, and project how a warming climate may affect landscape resistance and population connectivity in the future. We evaluate the influences of five potential future temperature scenarios involving different degrees of warming. We use resistant kernel dispersal models to assess population connectivity based on full occupancy of suitable habitat in each of these hypothetical future resistance layers. We use the CDPOP model to simulate gene exchange among individual martens in each of these hypothetical future climates. We evaluate: (1) changes in the extent, connectivity and pattern of marten habitat, (2) changes in allelic richness and expected heterozygosity, and (3) changes in the range of significant positive genetic correlation within the northern Idaho marten population under each future scenario. We found that even moderate warming scenarios resulted in very large reductions in population connectivity. Calculation of genetic correlograms for each scenario indicates that climate driven changes in landscape connectivity results in decreasing range of genetic correlation, indicating more isolated and smaller genetic neighborhoods. These, in turn, resulted in substantial loss of allelic richness and reductions in expected heterozygosity. In the U.S. northern Rocky Mountains, climate change may extensively fragment marten populations to a degree that strongly reduces genetic diversity. Our results demonstrate that for species, such as the American marten, whose population connectivity is highly tied to climatic gradients, expected climate change can result in profound changes in the extent, pattern, connectivity and gene flow of populations.     

Dispersal of annual plants in hierarchically structured landscapes

The scale at which plants utilize spatially distributed resources may be determined by their ability to locate sites that can sustain population growth. We developed a spatially-explicit model of the dispersal of annual plants in landscapes which were hierarchically structured, i.e., the spatial pattern of suitable sites was nested and scale-dependent. Results show that colonizing ability and extinction probability are most sensitive to the mean dispersal distance of the species. Dispersal out of the parental site, but within the immediate neighborhood, was the most efficient means for population expansion. When landscape patterns change with scale then dispersal distances determine the spatial scales of habitat utilization. As a complicating factor, the type of statistical distribution of dispersal distances also influences the colonizing ability. However, the importance of dispersal distance mean and distribution decreased as the number and connectance of suitable sites increased. The results suggest that landscape models which consider the interaction between scale dependent changes in landscape pattern and species dispersal and establishment characteristics are relevant to many issues in community ecology, invasion biology, and conservation biology.     

Quantification of the environmental effectiveness of nature-based solutions for increasing the resilience of cities under climate change

Nature-based solutions (NBSs) enhance the potential for mitigation and adaptation to climate change in cities. Among the environmental benefits offered by these measures, enhanced biodiversity, increased carbon storage, reduction of extreme temperatures, and pluvial flood control are crucial. The purpose of this study was to establish an integrated methodology for quantifying the benefits of NBSs and complementary measures and to apply it in a neighbourhood of Donostia-San Sebastián (Spain), where two alternative designs that incorporated NBSs and complementary measures were designed. Then, the individual effectiveness of the four variables was measured using both in-situ measurements and modelling approaches. For the integrated effectiveness, a multi-criteria decision analysis was employed. Both the ‘feasible’ design and the ‘ideal’ one led to an increase in biodiversity (46 and 108 %, respectively) and carbon storage (50 and 130 %, respectively). When considering each measure independently, putting soil provided the highest benefits for carbon capture and biodiversity; meanwhile, planting woody species and installing light-coloured permeable pavements and water fountains reduced the mean radiant temperature by 26.5 K and the air temperature by 0.5 and 2.5 K, respectively, in specific places. Finally, the importance of quantifying the multiple environmental benefits of NBSs for the selection of climate-smart options in urban planning has been highlighted.     

Fire place preferences of forest visitors in northwestern Switzerland: Implications for the management of picnic sites

Some recreational activities in urban forests can cause extensive damage to soil and vegetation. In Switzerland, forest visitors frequently build fires outside picnic sites for barbecuing. This indicates that the existing picnic sites are either not attractive enough for these visitors, or that there are not enough sites for all the visitors during peak days. We used an on-site survey to assess the requirements of picnickers in two forest areas in the vicinity of Basle. Results showed that the existing picnic sites do not meet the requirements of some visitor groups, causing the respective visitors to make their own fires in locations that suit them better. There was a preference for sites near streams, away from forest roads and close to open spaces. Furthermore, while some visitors highly appreciated the well-equipped official sites, others preferred more natural infrastructure with pieces of stones forming a fire ring rather than concrete rims, and logs to sit on instead of benches. Picnic sites that are closer to the requirements of visitors who normally steer away from official sites might reduce the number of self-made fire rings. The study shows that understanding visitor behaviour is a prerequisite for the implementation of measures to reduce ecological impacts.     

水培番茄侧根对盐胁迫的响应

以番茄品种石头为试材,采用分根水培装置,剪除主根同侧侧根,对番茄根系进行盐胁迫试验。设盐胁迫浓度分别 为0（CK）、0.1%、0.2% 和0.3% 4 个处理,通过测定侧根的根系活力、根系干质量和根系形态参数等指标,研究番茄根系 在盐胁迫下的生长状况和耐盐阈值。结果表明：侧根的生长符合慢- 快-慢的Logistic 生长模型,盐浓度为0.1% 的胁迫推 迟了根系的生育进程,根系活力、根系干质量和根系形态参数均高于对照;盐浓度为0.2% 和0.3% 的胁迫下根系生育进程 均提前,根系干质量和根系形态参数均较对照下降,根系生长受到抑制。当主根受到伤害会激发侧根的生存潜力,进行补偿 生长。根系的形态参数对耐盐性的贡献较大,总根长、根表面积和根体积可作为根系的耐盐指标。综上,对侧根生长有利的 盐胁迫环境为浓度0.1% 的盐溶液,通过Logistic 模型可以预测根系生长的始盛点、高峰点和盛末点,从而采取有效措施对 盐胁迫下侧根的生长进行调控。     

Modelling dynamics of ecosystem services basket in Mediterranean landscapes: a tool for rational management

Natural ecosystems are life-supporting systems providing diverse ecosystem services (ESs) and benefits to human societies: e.g., food and clean water, recreation opportunities or climate regulation. The contribution of natural and semi-natural ecosystems to the provision of such services depends to a large extent on vegetation structure and composition, which, in turn, change as a result of interactions between human decisions about land management, and spontaneous biological and environmental processes. Rational management of these dynamic ecosystems requires an ability to predict short- and long-term effects of management decisions on the desired ESs. The vegetation then contributes to, and modifies, the products and services obtained from the land. We applied mathematical modeling to study these complex relationships. We developed a model for a Mediterranean ecosystem which predicts the dynamics of multiple services in response to management scenarios, mediated by vegetation changes. Six representative ESs representing different groups were selected, based on available scientific information, for a detailed study: (1) density of geophytes, (2) potential contribution to honey production, (3) energy density of fleshy fruits foraged by birds, (4) forage for goats, (5) forage for cattle, and (6) carbon retention in woody plants. Mean contributions to each service by different vegetation cover types were estimated, and the overall service provided by the site was calculated as a weighted mean of these contributions. Services were measured in their appropriate units and subsequently standardized to a percentage of the maximum value observed in the study area. We attempted to combine all studied ESs, despite their different nature, into one “ESs basket”. This paper presents the dynamics of simulated vegetation composition and values of services in response to management scenarios involving grazing, fire and their combinations. Our approach can help land managers to evaluate alternative management scenarios by presenting the “services basket” obtained from the entire managed area.     

Establishment of human pancreatic tumor xenograft mouse model for evaluating tumor-homing and gene-silencing effects of siRNA-loading nanoparticles

AIM：To establish an effective and rapid method to develop transplanted subcutaneous pancreatic carcinoma by inducing PANC-1 cells into nude mice, and then use this mouse model to evaluate the tumor-homing and gene-silencing effects of siRNA-loading nanoparticles in vivo. METHODS：Different numbers of PANC-1 cells in 100 μL or 300 μL PBS were inoculated subcutaneously into the right flank of BALB/c (nu/nu) mice. When the tumor volume reached 100 mm3, siRNACY5.5 nanoparticles were injected through the mouse tail vein to perform in vivo imaging assay. Besides, the mice were randomly divided into 3 treatment groups treated with PBS, scrambled control RNA nanoparticles and siKras nanoparticles, respectively. The protein expression of Kras was detected by Western blotting and immunohistochemical staining. RESULTS：After inoculated with 1×107 PANC-1 cells in 300 μL PBS, all mice developed tumors within 2 weeks. The in vivo results showed that siRNA-loading nanoparticles accumulated in the tumor tissues and exerted gene silencing effect. CONCLUSION:In the present study, an effective and rapid method was established for PANC-1 cells to induce transplanted subcutaneous pancreatic carcinoma in nude mice within 2 weeks, which is suitable for in vivo imaging and treatment evaluations as a reproducible and reliable way for the further experiments.     

Assessment of tree structure using a 3D image analysis technique—A proof of concept

Efforts to improve the efficiency and efficacy of tree structure and crown architecture measurement are necessary to reduce error associated with indirect estimation of volume, which affects biophysical and ecosystem modelling, as well as resource assessment. In this short communication, we test the potential for a commercial SfM-MVS (Structure from Motion coupled with Multiple-View Stereophotogrammetry) software package, Photoscan-Professional, to accurately determine tree height, stem diameter, and eventually volume. SfM is a technique in computer vision, which calculates the 3D position of objects in a scene from a series of photographs. It uses a technique assuming that an object in a 3D scene is located on a vector between the image of the object in the camera and the object itself. The technique allows the construction of a 3D pointcloud, such as the one produced by laser technologies – terrestrial or airborne LiDAR. SfM requires no camera calibration or control points to construct an initial model. Moreover, it is a low-cost alternative to laser technologies. The second part of our method – MVS – is a visualization technique that reconstructs a 3D textured mesh of the scene from the SfM-derived pointcloud and RGB photographs. As a proof of concept, our methods were limited to two scenarios: (1) a single potted tree in a lab environment, where exact measurements could be made, and (2) two trees of different species and size in natural environments to test feasibility outside the laboratory. Precise measurements of tree height and stem diameter were compared with estimates obtained from the 3D model created using SfM-MVS. The results indicate that the SfM method is a promising – and inexpensive – alternative to terrestrial LiDAR and 3D scanners. Tree height estimates had error of 2.59%, while stem diameter estimates had error of 3.7%. The MVS algorithm used in this study was developed for plan surfaces such as topography or ‘compact’ objects and does not provide a representative 3D mesh for slender trees, although it works well for large stems. The authors link this disparity to the complex branching structure of trees.Future work requires (1) the development of effective automated volume reconstruction software specific to trees, and (2) the validation of the wide-scale applicability of the technology, which must include trees of various size, species, and growth forms. Moreover, future testing must include more complex environments, such as heterogeneous urban sites or closed-canopy forest sites where the proximity of other features may limit the utility of the new technology.     

Study on VIP-immunoreactive nerve fibers in dental pulp- dentine complex of human premolar

AIM: To investigate the impact of aortic bypass of different flow on hemodynamic changes caused by abdominal aorta occlusion. METHODS: A pig ischemic model was established by cross-clamping of the abdominal aorta above the celiac artery for 1 hour, and aortic bypass was used at the same time. The different flow of aortic bypass were placed between the proximal abdominal aorta and the left common iliac artery by using a roller pump. Two kinds of bypass flow rate were used with 50% and 70% of the volume of abdominal aorta flow cross-clamped site. The major hemodynamic changes were monitored during the different aortic cross-clamping and unlamping periods. RESULTS: All pigs without bypass (simple cross-clamping group) developed severe hemodynamic disturbance . Proximal arterial pressure rose markedly and distal arterial pressure dropped drastically during the period of cross-clamping, and there was a significant drop in the arterial pressure after unclamping. Heart rate increased obviously, and urine outputs decreased significantly compared with pre-clamping. The animals also developed a serious metabolic acidosis. In 70% flow group, the aforementioned values improved significantly when compared with that of 50% flow group. CONCLUSION: There was a severe hemodynamic alteration when the proximal abdominal aorta was cross-clamped for 1 hour, and the injury changes could be well prevented when the flow of aortic bypass was up to 70% of the volume of abdominal aorta flow.     

Scale-dependent proximity of wildlife habitat in a spatially-neutral Bayesian model

Organisms may be constrained by the energetic costs incurred while obtaining resources in fragmented landscapes. We used a spatially neutral model of deer wintering habitat to evaluate the effects of landscape fragmentation on the aggregation of deer habitat. The spatially neutral model used Bayesian probabilities to predict where deer wintering areas occurred. The probabilities were conditional on 12 landscape variables measured at 22,750 contiguous 0.4 ha locations. The model predicted deer habitat at each location independently, thereby enabling a comparison of habitat aggregation in observed, simulated, and random distributions of deer habitat. The predictions of the neutral model exhibited greater fragmentation than observed in nature, suggesting that suitable, yet isolated, locations were not visited by deer. The most suitable sites for deer were clumped in the neutral model, regardless of scale. The inclusion of less suitable sites preserved significant aggregation at fine scales but not at broad scales. Species operate at different scales within a landscape, so ecologists, nature reserve designers and natural resource planners may benefit from models that focus on the proximity of habitat sites as a function of both spatial scale and habitat quality.     

A general grass growth model for urban green spaces management in tropical regions: A case study with bahiagrass in southeastern Brazil

Urban green spaces (UGS) positively impact the population, providing essential ecosystem services and improving public health. Urban vegetation management needs to optimize mowing process costs and reducing impacts on the natural ecosystem. Thus, we implemented a general grass growth model suitable for UGS management in tropical areas, focused on lawns, public parks and squares, roadsides, and around waterways. The model incorporates local edaphoclimatic conditions to simulates the daily dynamics of leaf area index (LAI), biomass, evapotranspiration, and soil water content, going under mowing processes or not, with spatialization capability which might be integrated within geographic information system (GIS) environments. A case study assessing bahiagrass (Paspalum notatum Flüggé) vegetation species in São Carlos, southeastern Brazil, is presented, considering two scenarios to demonstrate the spatial capabilities of the model: (i) UGS as a single area, and (ii) several areas independently. For model validation, vegetation indices calculated based on data from an unmanned aerial vehicle (UAV) and CubeSat imagery (PlanetScope) were used to retrieve LAI time series, calibrated with spectral signatures from leaf ground sampling. For performance analysis, LAI time series from the model and LAI retrieved from both sensors were compared via determination coefficient (R²⁾ and root mean square error (RMSE). Our findings suggest that the proposed model is accurate, and due to its spatialization capability and integration with a GIS, its application may help government administrations to optimize UGS mowing processes.     

Competing land use in the reserve site selection problem

The objective of this paper is to present an approach that addresses competing land uses in the reserve site selection problem. This approach is implemented in a spatial optimization model for conservation planning in human-dominated landscapes: MENTOR. This model allocates new sites as stepping stones between existing sites. We illustrated the model by a case with competition for space between wildlife habitat and agriculture as it occurs in the Netherlands. We focused on deciduous forests with the European nuthatch Sitta europaea as an umbrella species for forest birds. Suitability maps for deciduous forests and for agriculture were applied as input for the allocation model.Effects on the landscape pattern, nuthatch populations, bird species richness and dairy farming were described. We can conclude that the application of MENTOR leads to an effective reserve network in De Leijen concerning the suitability of the land for dairy farming. The results show a doubling of the average proportion of occupied habitat, an increase in colonization probability of patches, a decrease in extinction probability of local populations, and an increase in bird species richness per patch. Whereas it results in a relatively small reduction in land currently used by agriculture.     

Long-term changes in willow spatial distribution on the elk winter range of Rocky Mountain National Park (USA)

We determined changes in willow (Salixspp.) cover in two valleys of the eastern slope of Rocky Mountain National Park,Colorado, USA, and related these changes to suspected causative factors. Changes in vegetation were inferred from digital maps generated from aerial photo-interpretation and field surveys conducted with a global positioning system. The decrease in riparian shrub cover was approximately 20% in both valleys over the period between 1937/46 and 1996, while the decline in tall willow (> 2 m tall) cover was estimated to be approximately 55%in both valleys. Suppressed willows (< 1.5 m tall) were predominantly located in areas affected by flooding and in areas where major river reductions were observed. Both valleys had sites that were being colonized by willows in wet meadows, and open areas created by flood disturbance. The potential causes of willow decline are many. Willow decline was associated with simplification of river spatial pattern, i.e., less complex branching and channelization, and a large flood disturbance. The causes of the reduction in river meanders were not determined, but are likely related to a decline in beavers, an increase in elk, and, possibly climate change. An increase in elk placed increased browsing pressure on willow during the period of the willow decline. Other factors such as climate changes and human activities could have also contributed to the willow decline. The persistence of these riparian ecosystems depends in large part on biotic interactions, particularly between willow, beaver, and elk. This revised version was published online in July 2006 with corrections to the Cover Date.     

Does urban gardening increase aesthetic quality of urban areas? A case study from Germany

We tested in two corresponding studies the hypothesis that urban gardening is of visual aesthetic value to the public. With the help of photo-realistic visualizations and a written questionnaire, 109 students and employees of the Karlsruhe University of Education (study 1) and 200 passers-by in the city of Karlsruhe (study 2) were asked about their opinion on different urban gardening scenarios, and attitudes towards urban gardening. Our results indicate that urban gardening can contribute to perceived attractiveness of urban areas, but that not all approaches are perceived as equally positive. While flowerbeds or flower meadows and orderly-managed vegetable plots, in comparison to conventional lawns, increased the aesthetic appeal of urban green space, container gardening approaches, which were often characterized as chaotic, did not. Although flower scenarios were preferred over vegetable scenarios, participants were rather positive about the idea of having more vegetable plots around. Socio-demographic variables had only minor influences on preferences and attitudes. As people were fonder of flowerbeds or flower meadows than of vegetable plots, a mixture of both might be advisable in urban gardening sites. This would also increase overall diversity, which is not only beneficial from an aesthetic, but also from an ecological point of view.     

Physico-chemical heterogeneity in a glacial riverscape

Spatio-temporal heterogeneity in physico-chemical conditions associated with the annual expansion/contraction cycle in a complex glacial flood plain of the Swiss Alps was investigated employing a landscape approach. The diverse and dynamic aquatic habitats of the flood plain were visualized as an aquatic mosaic or riverscape. Based on samples collected at ca. monthly intervals for 1.5 yr along 17 floodplain transects, the 3 components of riverscape heterogeneity, extent, composition, and configuration, were quantified using categorical maps and indices of landscape patterns for turbidity and specific conductance. Changes in the spatial heterogeneity of 13 other physico-chemical parameters were further analyzed by means of a within-dates principal component analysis. Riverscape heterogeneity (RH), quantified by applying several indices of landscape pattern to turbidity and specific conductance data, was minimum during groundwater-dominated base flow in winter. Despite an increase in surface connectivity in the channel network with rising discharge, RH rose in spring and summer as additional chemically-distinct water sources (i.e., snowmelt runoff and glacial ablation) contributed to surface flow within the flood plain. Most other physico-chemical variables measured during this study exhibited the same spatio-temporal heterogeneity as turbidity and specific conductance. Overall, the glacial flood plain shifted from a monotonous physico-chemical riverscape in winter to a complex mosaic in summer, this seasonal pattern being clearly driven by hydrological factors operating at the catchment scale rather than by autogenic processes within individual water bodies. Although RH exhibited a predictable annual pattern in response to the seasonal flow regime, we expect the channel network to undergo future modifications from stochastic factors associated with flood events and long-term changes reflecting movements of the glaciers.     

Stability of cerebral focal ischemia/reperfusion model induced by monofilament in Kunming mice

AIM: To study the stability of mouse cerebral ischemia/reperfusion model induced by the method of monofilament. METHODS: Sixty male Kunming mice were divided into 3 groups according to the body weight: group A (18-21 g), group B (22-28 g) and group C (30-35 g). Ischemia/reperfusion (I/R) model was made by middle cerebral artery occlusion (MCAO) with nylon monofilament. To evaluate the mouse MCAO model, the method of PRM2 laser Doppler was used to detect the cerebral blood flow, the neurological deficit scores were determined by Longa standard and infarction volume was detected with TTC staining. The content of malondialdehyde (MDA) and activity of superoxide dismutase (SOD) were also measured by ELISA. RESULTS: The successful rates of model establishment in both group A and group B were higher than that in group C (P＜0.05), especially the highest in group B . The mortality in group A was significantly higher than that in group B and group C (P＜0.05). The behavior scores and cerebral infarct volume in group A and group B were significantly higher than those in group C (P＜0.05). Obvious brain injury and neurological deficits were also observed in group A and group B with the higher content of MDA and the lower activity of SOD in the cerebral cortex of the injury side. CONCLUSION: There are three important factors to ensure the success and stability of MCAO mouse model induced by monofilament, i.e. the diameter of monofilament matching the body weight of the mice, the suitable length of monofilament within the blood vessel, as well as the maintaining of proper room temperature during experiment. The MDA content and SOD activity are also effective indexes for evaluating the cerebral I/R injury.