The natural upper boundary of a forest（forest line） in mountain environments is an indicator of climate conditions. An increase in global average temperatures has resulted in an upward advance of the forest line. Th...The natural upper boundary of a forest（forest line） in mountain environments is an indicator of climate conditions. An increase in global average temperatures has resulted in an upward advance of the forest line. This advance may result in fragmentation of the alpine ecosystem and a loss of biodiversity. Therefore, it is important to identify potential areas where current forests can advance under scenarios of future climate change. I used expert knowledge and cartographic modeling to create a hybrid cartographic model considering five topographic variables to predict areas where forest line can expand in the future.The prediction accuracy of the model is around 82%. The model is able to predict areas above the current forest line that are suitable or unsuitable for future forest advance.Further inclusion of high-resolution satellite imagery and digital elevation models, as well as field-based information into the model can help to improve the model accuracy.展开更多
Local communities depend on Kalinzu Forest Reserve (KFR) for plant resources. This resource utilization affects the population of tree species in the forest. This study set out to estimate the population of ten tree s...Local communities depend on Kalinzu Forest Reserve (KFR) for plant resources. This resource utilization affects the population of tree species in the forest. This study set out to estimate the population of ten tree species in the forest. Results of this study are hoped to provide a basis for studying future changes in population dynamics of the species. The ten species selected were: Newtonia buchananii, Cynometra alexandrei, Teclea nobilis, Prunus africana, Entandrophragma exelsum, Sapium ellipticum, Diospyros abyssinica, Zanthoxylum gilletii, Rytiginia kigeziensis and Spathodea nilotica. Their selection was based on the results of a study (Aine-Omucunguzi et al., 2010) about utilization of plant resources by the local people around KFR. Species with high demand from the local people were selected. Alternate nested quadrants along five line transects, were used to estimate the population. The plants were categorized into three classes as trees (>5 cm diameter at breast height), saplings (2 cm root collar diameter-5 cm diameter at breast height) and wildings (<2 cm root collar diameter). Population, population density, relative density, frequency, and relative frequency of each species were determined. Generally, the number of wildings, saplings and trees of each species increased away from the forest edge inwards. For all the species, wildings had the highest population density followed by saplings and then trees. Teclea nobilis had the highest number of individual per hectare, followed by Newtonia buchananii, while Rytiginia kigeziensis and Spathodea nilotica had the lowest number of individuals per hectare.展开更多
The existing methods for detection of the cloud scenes are applied at relatively small spectral range within shortwave upwelling radiative wavelength flux. We have reported a new method for detection of the cloud scen...The existing methods for detection of the cloud scenes are applied at relatively small spectral range within shortwave upwelling radiative wavelength flux. We have reported a new method for detection of the cloud scenes based on the Radiance Enhancement (RE). This method can be used to cover a significantly wider spectral range from 1100 nm to 1700 nm by using datasets from the space-orbiting micro-spectrometer Argus 1000. Due to high sunlight reflection of the smoke originated from the forest or field fires the proposed RE method can also be implemented for detection of combustion aerosols. This approach can be a promising technique for efficient detection and continuous monitor of the seasonal forest and field fires. To the best of our knowledge this is the first report showing how a cloud method can be generalized for efficient detection of the forest fires due to combustion-originated reflectance.展开更多
The article deals with the prduction lines in log yard by investigating the utilizationof machines in forest areas,presents the methods and rules of differentiating the log productionlines and also summarizes the form...The article deals with the prduction lines in log yard by investigating the utilizationof machines in forest areas,presents the methods and rules of differentiating the log productionlines and also summarizes the formation and development of three kinds of log production lines innortbeast forest areas of China.It gives different combination types of log production lines andtheir applications, so it is significant for us to evaluate and standardize the log Production lines.展开更多
科学合理的车站分类对于客流特征研究预测、车站设施布局优化以及周边土地开发建设具有重要意义。针对新线开通前新建车站客流数据未知而导致车站分类不准的问题,提出一种基于地铁客流与建成环境映射关系的新线车站分类方法。首先,从客...科学合理的车站分类对于客流特征研究预测、车站设施布局优化以及周边土地开发建设具有重要意义。针对新线开通前新建车站客流数据未知而导致车站分类不准的问题,提出一种基于地铁客流与建成环境映射关系的新线车站分类方法。首先,从客流角度选取组合聚类指标对既有车站进行聚类,形成各类车站的客流特征区间。其次,从建成环境角度计算既有车站的土地混合熵、不同POI(Point of interest)数量、度和介数等特征,利用随机森林(Random forest,RF)重要度指标筛选和对数变换拟合确定建成环境特征与地铁客流特征的映射关系表达式。最后,输入新线车站的建成环境特征,依据上述映射关系计算新线车站的客流特征值,结合既有车站的客流特征区间进行新线车站客流特征归类,实现客流数据缺失条件下的新线车站分类。为验证方法有效性,采用北京地铁数据进行案例验证。研究结果表明:基于地铁客流与建成环境映射关系的分类方法能够实现新线车站开通前的车站类型提前划分,具有较好的分类结果;进一步分析发现工作日车站与周末车站分类存在的差异与通勤行为特性、土地开发程度有关;研究方法在不同线路数据集上都表现出较好的分类效果,具有较强的适用性。研究结果可为缺失数据条件下的车站分类和新线开通期地铁运营组织提供新的思路和方法。展开更多
文摘The natural upper boundary of a forest（forest line） in mountain environments is an indicator of climate conditions. An increase in global average temperatures has resulted in an upward advance of the forest line. This advance may result in fragmentation of the alpine ecosystem and a loss of biodiversity. Therefore, it is important to identify potential areas where current forests can advance under scenarios of future climate change. I used expert knowledge and cartographic modeling to create a hybrid cartographic model considering five topographic variables to predict areas where forest line can expand in the future.The prediction accuracy of the model is around 82%. The model is able to predict areas above the current forest line that are suitable or unsuitable for future forest advance.Further inclusion of high-resolution satellite imagery and digital elevation models, as well as field-based information into the model can help to improve the model accuracy.
文摘Local communities depend on Kalinzu Forest Reserve (KFR) for plant resources. This resource utilization affects the population of tree species in the forest. This study set out to estimate the population of ten tree species in the forest. Results of this study are hoped to provide a basis for studying future changes in population dynamics of the species. The ten species selected were: Newtonia buchananii, Cynometra alexandrei, Teclea nobilis, Prunus africana, Entandrophragma exelsum, Sapium ellipticum, Diospyros abyssinica, Zanthoxylum gilletii, Rytiginia kigeziensis and Spathodea nilotica. Their selection was based on the results of a study (Aine-Omucunguzi et al., 2010) about utilization of plant resources by the local people around KFR. Species with high demand from the local people were selected. Alternate nested quadrants along five line transects, were used to estimate the population. The plants were categorized into three classes as trees (>5 cm diameter at breast height), saplings (2 cm root collar diameter-5 cm diameter at breast height) and wildings (<2 cm root collar diameter). Population, population density, relative density, frequency, and relative frequency of each species were determined. Generally, the number of wildings, saplings and trees of each species increased away from the forest edge inwards. For all the species, wildings had the highest population density followed by saplings and then trees. Teclea nobilis had the highest number of individual per hectare, followed by Newtonia buchananii, while Rytiginia kigeziensis and Spathodea nilotica had the lowest number of individuals per hectare.
文摘The existing methods for detection of the cloud scenes are applied at relatively small spectral range within shortwave upwelling radiative wavelength flux. We have reported a new method for detection of the cloud scenes based on the Radiance Enhancement (RE). This method can be used to cover a significantly wider spectral range from 1100 nm to 1700 nm by using datasets from the space-orbiting micro-spectrometer Argus 1000. Due to high sunlight reflection of the smoke originated from the forest or field fires the proposed RE method can also be implemented for detection of combustion aerosols. This approach can be a promising technique for efficient detection and continuous monitor of the seasonal forest and field fires. To the best of our knowledge this is the first report showing how a cloud method can be generalized for efficient detection of the forest fires due to combustion-originated reflectance.
文摘The article deals with the prduction lines in log yard by investigating the utilizationof machines in forest areas,presents the methods and rules of differentiating the log productionlines and also summarizes the formation and development of three kinds of log production lines innortbeast forest areas of China.It gives different combination types of log production lines andtheir applications, so it is significant for us to evaluate and standardize the log Production lines.
文摘科学合理的车站分类对于客流特征研究预测、车站设施布局优化以及周边土地开发建设具有重要意义。针对新线开通前新建车站客流数据未知而导致车站分类不准的问题,提出一种基于地铁客流与建成环境映射关系的新线车站分类方法。首先,从客流角度选取组合聚类指标对既有车站进行聚类,形成各类车站的客流特征区间。其次,从建成环境角度计算既有车站的土地混合熵、不同POI(Point of interest)数量、度和介数等特征,利用随机森林(Random forest,RF)重要度指标筛选和对数变换拟合确定建成环境特征与地铁客流特征的映射关系表达式。最后,输入新线车站的建成环境特征,依据上述映射关系计算新线车站的客流特征值,结合既有车站的客流特征区间进行新线车站客流特征归类,实现客流数据缺失条件下的新线车站分类。为验证方法有效性,采用北京地铁数据进行案例验证。研究结果表明:基于地铁客流与建成环境映射关系的分类方法能够实现新线车站开通前的车站类型提前划分,具有较好的分类结果;进一步分析发现工作日车站与周末车站分类存在的差异与通勤行为特性、土地开发程度有关;研究方法在不同线路数据集上都表现出较好的分类效果,具有较强的适用性。研究结果可为缺失数据条件下的车站分类和新线开通期地铁运营组织提供新的思路和方法。
