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111.
International case studies of protected area performance increasingly report that conservation and socio‐economic outcomes are interdependent. Effective conservation requires support and cooperation from local governments and communities, which in turn requires that protected areas contribute to the economic well‐being of the communities in which they are sited. Despite increasing recognition of their importance, robust studies that document the socio‐economic impacts of protected areas are rare, especially in the developed world context. We proposed 3 potential pathways through which protected areas might benefit local communities in the developed world: the improved local housing value, local business stimulus, and increased local funding pathways. We examined these pathways by undertaking a statistical longitudinal analysis of 110 regional and rural communities covering an area of approximately 600,000 km2 in southeastern Australia. We compared trends in 10 socio‐economic indicators describing employment, income, housing, business development and local government revenue from 2000 to 2010. New protected areas acquisitions led to an increased number of new dwelling approvals and associated developer contributions, increased local business numbers, and increased local government revenue from user‐pays services and grants. Longer‐term effects of established protected areas included increased local council revenue from a variety of sources. Our findings provide support for each of our 3 proposed benefit pathways and contribute new insights into the cycling of benefits from protected areas through the economy over time. The business and legislative models in our study are typical of those operating in many other developed countries; thus, the benefit pathways reported in our study are likely to be generalizable. By identifying and communicating socio‐economic benefits from terrestrial protected areas in a developed world context, our findings represent an important step in securing local support and ongoing high‐level protection for key components of the world's biodiversity. 相似文献
112.
为研究矿井火区中一氧化碳(CO)、氢气(H_2)、乙烯(C_2H_4)和乙烷(C_2H_6)等其他可燃气体对甲烷(CH_4)爆炸特性的影响,利用可视球形气体爆炸系统开展了多元可燃气体爆炸压力特性试验,观察并分析了峰值爆炸压力、最大爆炸压力上升速率及其相应时间。通过高速摄影系统拍摄了视窗范围内爆炸火焰传播图像,基于边缘检测方法确定了火焰前锋位置,继而得到最大火焰传播速度。分析了以氢气为主要成分的其他可燃气体对低浓度CH_4-空气混合物压力特性和火焰传播行为的影响。结果表明,多元可燃气体的存在增加了低浓度CH_4-空气混合物的爆炸危险性。随混合气体体积分数增加,低浓度CH_4-空气混合物的峰值爆炸压力、最大爆炸压力上升速率和最大火焰传播速度非线性增加;此外,到达峰值爆炸压力、最大爆炸压力上升速率的时间显著缩短。 相似文献
113.
In the current paper, we studied downtime at work. Downtime represents a unique aspect of work time, as employees have low workload and more discretion about their activities but are still paid to be at work. Despite its prevalence and potentially significant implications for productivity and well‐being, the experience of downtime has not been a focus in the literature. To study this phenomenon, we first used a qualitative method involving 15 focus groups. Results from 95 employees showed that downtime is distinct from formal breaks and withdrawal behavior and is generally a negative subjective experience. Categories of antecedents of experience and downtime activities were classified. Next, to further explore the phenomenon, and based on Study 1 and relevant literature, we proposed several hypotheses and tested them using an experience sampling method. Results from 86 employees (across 5 workdays and 689 data points) indicated that the amount of downtime was negatively related to day level job satisfaction, job performance, and subjective health. The duration of relaxation activities during downtime mitigated the negative effects of downtime on fatigue. The effects of enjoyment level of the activities, job autonomy, work engagement, and boredom proneness were also examined. Implications, limitations, and future research are discussed. 相似文献
114.
F. Daunt V. Afanasyev J. R. D. Silk S. Wanless 《Behavioral ecology and sociobiology》2006,59(3):381-388
In temperate regions, winter presents animals with a number of challenges including depressed food abundance, increased daily
energy requirements, higher frequency of extreme weather events and shortened day length. Overcoming these constraints is
critical for overwintering survival and scheduling of future breeding of long-lived species and is likely to be state dependent,
associated with intrinsic abilities such as food acquisition rates. We examined the relationship between environmental and
intrinsic factors on overwintering foraging and subsequent breeding phenology of the European shag Phalacrocorax aristotelis, a diurnal marine predator. We tested a range of hypotheses relating to overwintering foraging time and location. We found
that individuals greatly increased their foraging time in winter to a peak of more than 90% of available daylight at the winter
solstice. The seasonal patterns of foraging time appear to be driven by a combination of light levels and weather conditions
and may be linked to the availability of the shag's principal prey, the lesser sandeel Ammodytes marinus. There was no evidence that shags dispersed south in winter to increase potential foraging time. Foraging time decreased
after the winter solstice and, crucially, was correlated with subsequent breeding phenology, such that individuals that spent
less time foraging in February bred earlier. The relationship was much stronger in females than males, in line with their
more direct control of timing of breeding. Our results demonstrate that pre-breeding intrinsic foraging ability is critical
in determining breeding phenology. 相似文献
115.
Michele?ArestaEmail author Angela?Dibenedetto Carlo?Fragale Tiziano?Pastore 《Environmental Chemistry Letters》2004,2(1):1-4
Mechanical energy has been used so far for running chemical reactions and for preparing new materials in absence of solvents. Very recently, the technology has been applied to solve environmental problems. In this paper, we describe the application of high-energy milling (HEM) for the remediation of soils contaminated by chlorinated organic compounds such as polychlorobiphenyls (PCBs) and agrochemicals like atrazine. NaBH4 and LiAlH4 have been successfully used for the total dehydrohalogenation of both classes of compounds, leaving a residue lower than 2 ppmw of the starting compound in the treated soil. LiAlH4 was found to be more active than NaBH4. 相似文献
116.
东江水源林不同混交组合林地枯落物和土壤持水能力研究 总被引:11,自引:0,他引:11
东江是广东省重要的河流,东江水源林的质量直接关系到流域内的社会和经济的发展,关系到深圳和香港的生活用水。作者针对现有水源林生态功能较差的情况,在广东省东源县设计和营造了8种不同混交类型的水源林,并对其林地枯落物和土壤持水能力进行了调查研究。结果表明,与对照的马尾松纯林相比,红锥×枫香混交组合、楠木×锥栗混交组合以及格木×海南红豆混交组合林地枯落物持水能力有较大提高;枫香×樟树混交组合、楠木×锥栗混交组合、红苞木×枫香混交组合以及红锥×枫香混交组合土壤持水能力明显提高。综合枯落物和土壤持水特性对各混交类型进行聚类分析,将8个混交组合进行分类,其中椆木×红锥混交组合、马尾松纯林、火力楠×红锥混交组合以及木荷×椆木混交组合林地持水能力较差;格木×海南红豆混交组合和红锥×枫香混交组合林地持水能力一般;红苞木×枫香混交组合和枫香×樟树混交组合林地持水能力较好;楠木×锥栗混交组合林地持水能力最好。总体上,造林初期,水源涵养试验林在提高原有林地持水能力方面已取得了一定的效果。 相似文献
117.
鼎湖山针阔叶混交林土壤酸度与土壤养分的季节动态 总被引:4,自引:1,他引:4
研究了鼎湖山南亚热带森林演替系列中处于中间阶段的针阔叶混交林土壤的pH值、水解氮、速效磷、钾、交换性钙、镁等几种营养元素的含量现状及季节动态。结果表明:混交林土壤为强酸性土壤,表层(0--20cm)土壤酸度高于中(20--40cm)、下(40-60cm)层土壤,0~40cm土壤pH值具有明显的季节波动性。降雨、温度、凋落物、植物根系以及微生物的活动等因素可能是鼎湖山混交林土壤pH值季节动态变化的主要因素。除Ca外,在同一剖面内,表层土壤养分的含量明显高于中下层,而中下层之间相差不大,养分大多在冬季较高,随着季节变动(1,4,7,10月)呈下降趋势。 相似文献
118.
马尾松纯林及其与阔叶树混交林的凋落量与养分通量 总被引:7,自引:0,他引:7
在25a生马尾松林下分别套种1a生火力楠、闽粤栲、苦槠、格氏栲、青栲和拉氏栲等阔叶树种的幼苗,16a后形成郁闭的针阔混交异龄林.通过定位监测和化学分析,对上述6种混交林类型及林下未套种阔叶树的马尾松纯林的森林凋落量及养分通量进行了研究.统计结果显示,6个混交群落的年凋落量分别为7137.3kghm-2、6741.1kghm-2、8041.7kghm-2、7151.3kghm-2、7533.2kghm-2和6149.1kghm-2,而马尾松纯林的年凋落量仅3442.8kghm-2.在所有林分的凋落物组成中,枯叶占绝对优势,占凋落物总量的49.7%~71.5%,其余依次为枯枝(5.7%~26.1%)、其它组分(5.5%~17.1%)、树皮(7.7%~18.9%)和果实(0.7%~2.0%).各混交林分中来自马尾松的凋落物占50.4%~58.0%,而来自阔叶树的凋落物占42.0%~49.6%,且两者的组成存在明显差异.各林分总凋落量的季节动态呈双峰型,第1次峰值出现在2~4月份,第2次峰值出现在8、9月份.凋落物中主要养分元素的含量依林分类型、凋落物组分和凋落时间不同而异,N、P、K、Ca和Mg的含量范围依次为3.25~12.98gkg-1、0.23~0.97gkg-1、0.42~4.02gkg-1、7.34~32.57gkg-1和1.34~5.58gkg-1.不同的林分类型,凋落物中各养分元素的年通量大小均为:Ca>N>Mg>K>P.马尾松纯林中,通过凋落物的5种养分元素的年流通量为142.01kghm-2;而在林下分别套种上述6种阔叶树后,其养分年流通量依次增加到204.95kghm-2、223.93kghm-2、304.12kghm-2、288.46kghm-2、213.77kghm-2、238.05kghm-2.图3表4参13 相似文献
119.
玉米-花生混作系统中的氮铁营养效应 总被引:2,自引:0,他引:2
采用盆栽试验的方法研究了不同施氮水平和种间相互作用对花生铁营养、根瘤固氮能力以及系统氮营养的影响。结果表明,在本试验种植密度下,施氮水平和种植方式对下针期单株花生生物量无显著影响。在不同施氮水平下,玉米-花生混作不仅均显著改善了花生铁营养,而且玉米对氮素的大量吸收显著降低了混作花生根际土壤硝态氮的质量分数,从而使得花生根瘤数增加,根瘤固氮酶活性增强。混作花生铁营养受混作玉米氮营养及作物发育状况的影响较大,并且下针期花生固氮酶活性受施氮抑制及花生铁营养改善的促进。这说明,根际土壤硝态氮的质量分数的降低和花生铁营养的改善是石灰性土壤上花生固氮能力增强的关键因素,而花生生物固氮作用的增强是该混作系统体现氮营养优势的主要原因。 相似文献
120.
系统介绍用计算机辅助确定矿井外因火灾位置方法的原理,给出该方法的具体步骤,剖析其定性分析、定量分析和定量分析结果评价三大步骤中的各技术关键,并借助一个实例验证了该方法实用的可行性 相似文献