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11.
Forest fragmentation has several phases; thus, the ecological significance of each phase during a particular period of time must be interpreted. To interpret, this study quantifies the magnitude of forest loss and the changes in the temporal pattern of fragmentation in the State of Selangor, peninsular Malaysia. Using the decision tree model of land transformation, five phases of forest fragmentation were identified: perforation, dissection, dissipation, shrinkage and attrition. This analysis showed that the magnitude of forest loss was the highest during the dissipation phase. The patchiness analysis showed that dissipation contributes to the highest environmental uncertainty found for the forest patches. This study can be considered a first step in the exploration of the properties and the behavioural pattern shown by the spatial process of forest fragmentation.  相似文献   
12.
Many argue that monitoring conducted exclusively by scientists is insufficient to address ongoing environmental challenges. One solution entails the use of mobile digital devices in participatory monitoring (PM) programs. But how digital data entry affects programs with varying levels of stakeholder participation, from nonscientists collecting field data to nonscientists administering every step of a monitoring program, remains unclear. We reviewed the successes, in terms of management interventions and sustainability, of 107 monitoring programs described in the literature (hereafter programs) and compared these with case studies from our PM experiences in Australia, Canada, Ethiopia, Ghana, Greenland, and Vietnam (hereafter cases). Our literature review showed that participatory programs were less likely to use digital devices, and 2 of our 3 more participatory cases were also slow to adopt digital data entry. Programs that were participatory and used digital devices were more likely to report management actions, which was consistent with cases in Ethiopia, Greenland, and Australia. Programs engaging volunteers were more frequently reported as ongoing, but those involving digital data entry were less often sustained when data collectors were volunteers. For the Vietnamese and Canadian cases, sustainability was undermined by a mismatch in stakeholder objectives. In the Ghanaian case, complex field protocols diminished monitoring sustainability. Innovative technologies attract interest, but the foundation of effective participatory adaptive monitoring depends more on collaboratively defined questions, objectives, conceptual models, and monitoring approaches. When this foundation is built through effective partnerships, digital data entry can enable the collection of more data of higher quality. Without this foundation, or when implemented ineffectively or unnecessarily, digital data entry can be an additional expense that distracts from core monitoring objectives and undermines project sustainability. The appropriate role of digital data entry in PM likely depends more on the context in which it is used and less on the technology itself.  相似文献   
13.
土地利用规划环境影响评价的作用是为了实现土地的规划和环境相互适应、相互协调,为规划决策者提供一定的技术支撑。文章阐述了土地规划环境影响评价重要意义、内容及相关程序,同时也对此提出了针对性的建议,积极推进及完善土地利用规划环境影响评价在现阶段十分必要。  相似文献   
14.
Introduction: More than 800 pedestrians die annually in crashes on interstates and other freeways in the United States, but few studies have examined their characteristics. Method: Data from the Fatality Analysis Reporting System on pedestrians fatally injured during 2015–2017 were analyzed. Chi-square tests compared characteristics of pedestrians killed on interstates and other freeways with those that died on other roads, and across crash types among freeway deaths. Land use characteristics of locations where pedestrians were killed while crossing freeways in a large state (California) were identified using Google Earth. Results: A larger proportion of pedestrians killed on freeways died on dark and unlit roads (48% vs. 32%), were male (78% vs. 68%), or were ages 20–44 (55% vs. 32%) compared with pedestrians killed on other roads. Crossing (42%) was the most common crash type among pedestrian deaths on freeways, followed by disabled-vehicle-related crashes (18%). Pedestrians who died while crossing more often had blood alcohol concentrations ≥ 0.08 g/dL (40%) than those in disabled-vehicle-related (22%) or other crashes (34%). Deaths in crossing crashes were more likely than other freeway deaths to occur on urban roads (81%), at speed limits ≤50 mph (13%), or between 18:00 and 23:59 (49%), and 58% of crossing crashes analyzed for land use were located between residential and other (e.g., commercial, recreational) uses. Over a third (37%) of deaths in disabled-vehicle-related crashes occurred at speed limits ≥70 mph. Conclusions: A surprising proportion of pedestrian deaths occur on controlled-access roads not designed for walking. Countermeasures for these crashes need to be implemented to see meaningful reductions in pedestrian fatalities overall. Practical applications: Improving roadway and vehicle lighting, requiring reflective warning devices for marking disabled vehicles, constructing pedestrian overpasses and underpasses in areas frequently crossed, and promoting alternative means of traveling between residential and commercial areas could help.  相似文献   
15.
近10a来由于经济利益的驱动,橡胶、茶园、咖啡和桉树等人工园林在云南省西南部西盟县大规模种植,使土地利用结构和布局发生了较大变化,影响了种植区的生态系统服务价值。以西盟县为研究对象,基于2000年、2005年和2010年的遥感影像解译的土地利用/覆被数据,参照"中国生态系统单位面积生态服务价值当量",修订了西盟县生态系统单位面积服务价值,结合敏感度分析,探讨了土地利用/覆被变化及其对生态系统服务价值的影响。结果表明:(1)2000~2010年西盟县的耕地、园地、水域和乡镇用地面积增加,林地和草地面积减少,西南部的土地利用/覆盖类型相互转化主要表现在林地和耕地转化为园地,而东北部表现在林地转化为耕地;(2)从时间上看,生态系统服务价值呈减少趋势,10 a间净减少106.29×106元,林地的生态系统服务价值始终最高;(3)研究期内,只有食物生产服务有价值量的增加,其余生态系统服务的价值量均为不同程度的减少;(4)从空间上看,西盟县生态系统服务价值东北部和东南部高,西部、中部和东部低。力所乡生态系统服务价值有小幅度增加,其余乡镇均呈减少趋势。西盟县以经济利益为目的的发展模式给生态系统服务和可持续发展带来巨大压力,在一定程度上使区域整体生态效应下降。因此,西盟县的发展应该在保证生态系统稳定的前提下,适当发展园地,同时优化土地利用结构,在生态效益和经济利益之间,找到双赢的平衡点。  相似文献   
16.
以川东平行岭谷区典型岩溶槽谷--北碚槽上为研究区域,通过对8月和11月的岩溶地下水水化学性质研究,发现槽上岩溶地下水的化学性质呈现明显的季节性:电导率、矿化度、SO42-浓度及HCO3-浓度都是8月大于11月,与气温和降水量的变化相对应,也与人类在8月份对土地利用的强度大于在11月份对土地利用的强度相对应。研究区地下水的化学性质与人类活动对土地利用的季节差异具有比较明显的对应关系,为进一步认识岩溶地下水的时间变化规律提供科学数据,也有利于认识人类活动对生态环境产生的影响,从而采取更加合理的措施来治理和保护岩溶地区有限的地下水资源,满足人们的生活和生产需要。  相似文献   
17.
土地利用生态服务价值指标体系评估结果比较研究   总被引:5,自引:0,他引:5  
生态系统服务价值评估越来越受到学术界关注。针对当前生态服务价值评估方法、指标体系和评估效果较多的实践,通过文献归纳,对国内外土地利用生态服务价值评价方法、指标体系及其系数进行了梳理、分类和评价,将指标体系分为Costanza和谢高地两大类,并将谢高地指标体系分为价值当量、价值系数和区域修正。以辽宁省2005、2010年土地利用数据为案例,运用Costanza价值系数、谢高地两个版本价值当量、两个版本价值系数的区域修正,分别核算了案例区生态系统服务价值及变化,并比较评价结果。研究得出Costanza价值系数应用于中国实践时评估结果显得偏低,谢高地2002版的价值当量和2002版的价值系数区域修正结果最接近平均值,相对较为可取,2007版的价值系数区域修正评估结果也较为接近均值但略低,2007版的价值当量评估结果总体偏高。研究结果有利于指导土地利用生态服务价值评估指标体系选取。  相似文献   
18.
研究了pH、接种量、无机盐(通过加入磷酸二氢钾进行无机盐补充)及DO等对产朊假丝酵母处理马铃薯淀粉废水的影响.结果表明.在pH为5.0、产朊假丝酵母接种量为10%(体积分数)、磷酸二氢钾(质量分散为0.1%)加入量为0.5 g/L、废水不灭菌的条件下,废水处理效果和产朊假丝酵母生长最佳.且当废水COD为5 074 mg/L时,COD去除率达到74.86%,同时可获得2.23g/L的单细胞蛋白.产朊假丝酵母处理马铃薯淀粉废水的最佳条件的实验研究对实现马铃薯淀粉废水资源化利用提供了理论参考.  相似文献   
19.
Fishers and small-scale fisheries worldwide have been marginalized historically. Now it is clear that integrating fishers in management processes is key to resource conservation, but it is less clear how to do it. Here, based on a literature review and new information, we present and analyze a case in which the participation of fishers in the management process was crucial in recovering an overexploited small-scale fishery for the pirarucu (Arapaima spp.) in the Amazon Basin, Brazil. In 8 years of experimental management, from 1999 to 2006, the population of pirarucu increased 9-fold (from about 2200 to 20,650 individuals), harvest quotas increased 10-fold (from 120 to 1249 individuals), and fishers’ participation in the management process increased and they benefited from increased monetary returns. Additionally, the number of communities conducting the management scheme increased from 4 in 1999 to 108 in 2006, following the demands of fishers and regional government agencies. Based on our analysis, we suggest that the participation of fishers in the management of other small-scale fisheries in the world can be improved by focusing on (1) applying the knowledge and skills of fishers in resource monitoring and management, (2) bridging knowledge systems among all involved stakeholders, (3) collaborating with fishers that are interested in, and capable of conducting, resource conservation schemes, and (4) conducting management under conditions of uncertainty.  相似文献   
20.
In this study, we asked the Ariaal herders of northern Kenya to answer "why, what and how" they classified landscape, and assessed and monitored the biodiversity of 10 km(2) of grazing land. To answer the "why question" the herders classified grazing resources into 39 landscape patches grouped into six landscape types and classified soil as 'warm', 'intermediate' or 'cold' for the purpose of land use. For the "what question" the herders used soil conditions and vegetation characteristics to assess biodiversity. Plant species were described as 'increasers', 'decreasers' or 'stable'. The decreaser species were mostly grasses and forbs preferred for cattle and sheep grazing and the increasers were mostly woody species preferred by goats. The herders evaluated biodiversity in terms of key forage species and used absence or presence of the preferred species from individual landscapes for monitoring change in biodiversity. For the "how question" the herders used anthropogenic indicators concerned with livestock management for assessing landscape potential and suitability for grazing. The anthropogenic indicators were related to soils and biodiversity. The herders used plant species grazing preferences to determine the links between livestock production and biodiversity. By addressing these three questions, the study shows the value of incorporating the indigenous knowledge of herders into classification of landscape and assessment and monitoring of biodiversity in the grazing lands. We conclude that herder knowledge of biodiversity is related to the use as opposed to exclusive conservation practices. This type of knowledge is extremely valuable to conservation agencies for establishing a baseline for monitoring changes in biodiversity in the future.  相似文献   
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