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1.
为探究重污染天气期间济南市城区和清洁对照点PM_(2.5)及其组分污染特征,于2016年12月31日-2017年1月7日在市监测站和跑马岭进行连续PM_(2.5)样品采集,并对两个点位的PM_(2.5)及其组分(水溶性离子和碳质组分)污染特征进行分析。结果表明,重污染天气期间市监测站PM_(2.5)质量浓度(260±77)μg·m~(-3)是跑马岭(85±17)μg·m~(-3)的3倍,表明该重污染天气过程对济南市城区影响程度明显大于清洁对照点跑马岭。市监测站水溶性离子浓度高低顺序为SO_4~(2-)NO_3~-NH_4~+Cl~-K~+Na~+Ca~(2+)F~-,跑马岭水溶性离子浓度高低顺序为NO_3~-SO_4~(2-)NH_4~+Cl~-K~+Na~+Ca~(2+)F~-。市监测站和跑马岭二次无机离子(SNA)质量浓度分别为(134.7±49.5)μg·m~(-3)和(46.2±19.0)μg·m~(-3),在PM_(2.5)中占比分别是51.8%和54.4%,两个点位PM_(2.5)浓度差别很大,但SNA在PM_(2.5)中占比相差不大。通过NH_4~+计算值与实测值相关性分析可知,市监测站和跑马岭PM_(2.5)中NH_4~+均主要以(NH_4)_2SO_4和NH_4NO_3形式存在。市监测站SOR和NOR分别为0.44和0.32,跑马岭SOR和NOR分别为0.32和0.44,SOR和NOR的值均大于0.1,表明大气中SO_2和NO_2的二次氧化程度较高。采用OC/EC最小比值法估算得到市监测站和跑马岭SOC分别为8.3μg·m~(-3)和1.8μg·m~(-3),分别占OC的38.2%和20.9%,这表明市监测站OC二次反应程度明显高于跑马岭。市监测站有机碳(OC)和元素碳(EC)相关性(R~2=0.57)明显弱于跑马岭(R~2=0.92),表明市监测站OC和EC来源比较复杂,更有利于SOC的生成。  相似文献   

2.
张毅 《环境化学》2020,39(6):1699-1708
采集了2017—2018年秋冬季长治市审计局站、监测站、清华站等3个监测站点的大气PM_(2.5)样品,分析了其元素、水溶性离子及碳质组分特征,并利用化学质量平衡模型(CMB)对PM_(2.5)进行来源解析.结果表明,采样期间长治市PM_(2.5)浓度为67.9μg·m~(-3),其中审计局站PM_(2.5)浓度最高(70.6μg·m~(-3)),其次为监测站(70.0μg·m~(-3))和清华站(63.0μg·m~(-3));二次无机离子(SO_4~(2-)、NO~-_3、NH~+_4)平均浓度(20.7μg·m~(-3))占PM_(2.5)浓度的30.5%,与大量排放到大气中的SO_2、NO_2二次生成有关;OC(12.6μg·m~(-3))和EC(6.6μg·m~(-3))分别占PM_(2.5)的18.6%和9.7%;OC/EC为2.06,且SOC(5.9μg·m~(-3))在OC中占比高达63.1%,表明长治市秋冬季二次污染较重;典型地壳元素Si和Ca占元素组分平均浓度的29.8%和22.8%,说明扬尘污染对长治市PM_(2.5)的有一定影响;源解析结果表明,长治市秋冬季PM_(2.5)主要来源为:机动车源17.0%、燃煤源16.5%、扬尘源14.6%、二次硝酸盐13.9%、二次硫酸盐11.0%、二次有机气溶胶10.8%、工艺过程源9.3%、生物质燃烧源1.9%、其他源5.0%.因此,为进一步降低长治市环境空气中PM_(2.5)的污染,需在加强管控机动车,燃煤和扬尘等一次排放源的基础上,降低一次污染物SO_2、NO_2等的排放,从而实现对二次污染源前体物的控制.  相似文献   

3.
为探索北京城区大气细颗粒物浓度水平及其碳组分和二次水溶性无机离子的浓度特征,于2014年6月1日至7月15日在车公庄地区使用微量振荡天平(TEOM+FDMS)、EC/OC在线分析仪以及水溶性离子在线分析仪对PM_(2.5)质量浓度及其主要化学组分(OC、EC、SO_4~(2-)、NO_3~-和NH_4~+)进行了实时监测.研究结果表明,北京市城区夏季PM_(2.5)质量浓度平均值为69.0±47.9μg·m-3,PM_(2.5)中OC、EC、SO_4~(2-)、NO_3~-和NH_4~+所占的比例分别为15.8%、2.4%、23.0%、15.7%和19.2%,SNA(SO_4~(2-)、NO_3~-和NH_4~+)合计达到了PM_(2.5)质量浓度的57.9%.研究各组分的日变化特征发现,OC和SO_4~(2-)白天浓度变化较小,夜晚浓度稍高;NO_3~-和NH_4~+则随着光照和温度的增加而逐渐降低;EC呈现出夜晚浓度高白天浓度低的特点.研究各组分的相关性及比值发现,OC和EC的相关系数为0.62,OC/EC大于2.0,说明北京城区夏季存在着较为严重的二次污染;此外,NO_3~-/SO_4~(2-)平均比值为0.68,SOR和NOR的变化趋势基本一致,两者的平均值分别为0.55和0.14.通过分析北京市城区夏季不同浓度级别各组分的变化发现,随着PM_(2.5)质量浓度的增加,OC和EC所占的比例不断降低,而SNA比例则不断升高,其中NO_3~-浓度水平的增加最为显著.  相似文献   

4.
2017年1月—12月期间在四川省宜宾市布置4个点位,共采集360个PM_(2.5)样品膜,采用美国沙漠研究所DRI Model 2001型热光分析仪测定PM_(2.5)样品中OC、EC的浓度值,应用OC/EC比值法对SOC进行了估算.结果表明,宜宾市PM_(2.5)年均浓度为75.2μg·m~(-3).OC、EC年均浓度分别为14.3μg·m~(-3)和4.30μg·m~(-3),季节变化趋势为冬季秋季春季夏季,OC占PM_(2.5)比例为19.0%,为PM_(2.5)重要组成部分.SOC年均浓度为4.70μg·m~(-3),对OC贡献较大,在OC中占比为29.3%;SOC在OC中的占比春季冬季≈秋季夏季.进一步对OC1、OC2、OC3、OC4、EC1、EC2、EC3、和OPC进行主成分分析,结果表明机动车尾气、燃煤排放和生物质燃烧是宜宾市PM_(2.5)中OC和EC的主要贡献源,可贡献PM_(2.5)中碳组分的54.0%—69.0%.  相似文献   

5.
于2015年1月至11月在广州利用大流量大气颗粒物采样器采集细颗粒物(PM_(2.5))样品,并利用热光反射法(TOR)测定大气颗粒物中有机碳(OC)和元素碳(EC)浓度。结果表明,广州ρ(PM_(2.5))年均值为(69.5±35.6)μg·m~(-3),是GB 3095—2012《环境空气质量标准》中PM_(2.5)年均质量浓度二级标准限值(35μg·m~(-3))的2.0倍,表明广州大气细颗粒物污染严重。OC、EC和总碳气溶胶(TCA)的年均质量浓度分别为(8.31±4.53)、(3.56±2.72)和(16.85±9.60)μg·m~(-3),分别占PM_(2.5)质量浓度的13.2%、5.9%和27.0%,表明含碳组分是PM_(2.5)的重要组成部分。OC和EC浓度季节变化规律存在差异性,OC浓度在冬季最高,而EC浓度在秋季最高。OC和EC的相关性弱和比值高的特征结果表明冬季二次有机碳(SOC)污染最严重,其平均质量浓度为6.9μg·m~(-3),占OC质量浓度的62.4%。主成分分析结果表明,冬季和春季广州PM_(2.5)中碳组分来源较复杂,主要包括机动车尾气、燃煤和生物质燃烧,夏季碳组分的主导污染来源是燃煤和机动车尾气,而秋季碳组分主要来源于机动车尾气。  相似文献   

6.
快速的经济发展和城市化进程造成我国城市大气污染日益显著,并受到更为广泛的关注.为了解济南市大气细粒子及其化学成分的污染特征,于2013.10.15—2013.11.16和2013.12.24—2014.1.27(总观测天数为62天)利用中流量颗粒物采样器采集了济南市大气PM_(2.5)样品,分析了其中的化学成分,包括水溶性离子、无机金属元素、元素碳(EC)和有机碳(OC),并结合颗粒物质量重构法和主成分分析法探讨了济南市大气细粒子的来源.结果表明,监测期内济南市PM_(2.5)质量浓度严重超标,日均值均高于我国国家环境空气质量标准(GB3095—2012)中的一级标准,最高日均值达到了335μg·m~(-3).水溶性离子、有机碳、元素碳和金属元素分别占总PM_(2.5)浓度的45.3%、34.7%、2.3%、5.6%(秋季),42.8%、32.9%、3.6%、12.5%(冬季).二次水溶性离子NO_3~-、SO_4~(2-)和NH_4~+为主要的水溶性离子,分别占总离子浓度的34.1%、35.6%、9.2%(秋季)和35.2%、30.4%、15.9%(冬季).OC和EC的平均质量浓度分别为33.8μg·m~(-3)和4.3μg·m~(-3),OC/EC比值表明秋季汽车尾气与生物质燃烧对有机气溶胶的贡献较大,而冬季燃煤排放对有机气溶胶的贡献较大.化学质量重构结果表明,秋季济南市细粒子中二次无机盐、海盐、重金属、矿物尘、建筑尘、有机物和元素碳的质量百分比分别为38.6%、1.2%、0.2%、5.4%、1.4%、34.7%和2.3%,冬季分别为34.8%、1.5%、3.5%、7.5%、3.2%、33.0%和3.6%.主成分分析结果表明,汽车尾气及二次转化、燃煤以及冶炼工业排放是济南市大气细粒子的主要来源.  相似文献   

7.
为研究北京城区PM_(2.5)中有机碳(OC)和元素碳(EC)的浓度水平、季节变化特征与主要来源,于2015年4月至2016年3月在北京西三环交通带附近采集4个季节PM_(2.5)有效样品95组,利用热光反射法测定了PM_(2.5)中OC和EC的质量浓度,并对OC/EC值、OC与EC相关性、二次有机碳(SOC)等特征及污染来源进行了分析.结果表明,采样期间PM_(2.5)平均质量浓度为(109.9±7.99)μg·m~(-3). PM_(2.5)中OC的年平均质量浓度为(13.49±4.32)μg·m~(-3),占PM_(2.5)的13.13%; EC的年平均质量浓度为(5.41±1.83)μg·m~(-3),占PM_(2.5)的5.2%.OC和EC平均浓度及OC和EC在PM_(2.5)中所占比例的季节变化特征均为冬季最高,秋季大于春季,夏季最低.4个季节PM_(2.5)中OC/EC比值均大于2.0,表明各季节存在二次有机碳(SOC)的生成,采用OC/EC最小比值法对SOC含量进行了估算,SOC年平均浓度为(6.88±1.10)μg·m~(-3),占OC含量的50.86%,冬秋季节的SOC浓度水平高于春夏季节.夏季SOC对OC的贡献率为62.22%,高于其他季节.相关性分析表明,OC与EC的相关性在春季(R2=0.9046)和秋季(R2=0.8886)高于夏季(R2=0.4472)和冬季(R2=0.6018),表明春秋两季OC与EC来源相似且相对简单.进一步对PM_(2.5)中8个碳组分质量浓度进行分析显示,北京城区大气碳质气溶胶主要来自汽油车排放和燃煤.  相似文献   

8.
为研究太原市环境空气中含碳组分的时空分布变化规律,于2014年3月、5月、8月、12月采集了太原市3个点位春、夏、秋、冬等4个季节的PM_(2.5)样品,利用碳分析仪(DRI 2001A)测定了样品中OC1、OC2、OC3、OC4、EC1、EC2、EC3、OPC共8种碳组分含量,计算了有机碳(OC)、元素碳(EC)二者浓度,分析了OC和EC的时空分布特征.结果显示,太原市PM_(2.5)中OC和EC的平均质量浓度分别是13.5±14μg·m~(-3)和6.5±6.1μg·m~(-3),其中OC浓度随季节变化顺序为冬季春季夏季秋季,EC浓度季节变化与OC一致.春、夏、秋、冬4个季节总含碳气溶胶(TCA)占PM_(2.5)比例分别为17.6%、9.5%、8.8%、42.3%,其中冬季最高,表明冬季含碳气溶胶污染较为严重.夏季中OC和EC相关性较弱(R~2=0.4054),而春季(R~2=0.7659)、秋季(R~2=0.8253)、冬季(R~2=0.8184)OC和EC相关性较强,表明夏季碳气溶胶来源不同.通过(OC/EC)min最小比值法估算二次有机碳(SOC)浓度,春、夏、秋、冬季SOC浓度分别为2.8±2.9μg·m~(-3)、1.0±0.8μg·m~(-3)、 0.5±0.4μg·m~(-3)、 3.6±3.5μg·m~(-3),冬季SOC浓度最高. 8种碳组分分析结果显示,不同季节一次排放源中生物质燃烧、机动车尾气排放及煤炭燃烧对太原市含碳气溶胶贡献不同,其中,冬季燃煤和机动车排放使太原市含碳气溶胶污染严重,应加强燃煤和机动车排放源管控,来减轻碳组分污染.  相似文献   

9.
水溶性无机离子是PM_(2.5)的主要组分之一,对研究PM_(2.5)的物理化学性质,来源及其形成机理具有重要意义.本研究于2017年9月—2017年11月期间在贵阳城区采集了80个PM_(2.5)样品,并测定了8种水溶性离子浓度,探讨贵阳秋季PM_(2.5)水溶性离子组成特征及来源.结果表明贵阳秋季PM_(2.5)中无机离子的平均质量浓度为15.99μg·m~(-3),阴离子和阳离子的平均质量浓度分别为10. 90μg·m~(-3)、5. 09μg·m~(-3); SO_4~(2-)(8. 53±4.63μg·m~(-3))平均质量浓度最高,其次是NH_4~+(2.56±1.62μg·m~(-3))、NO_3~-(2.21±2.96μg·m~(-3))、Ca~(2+)(1.98±0.88μg·m~(-3)),最后依次是K~+(0.37±0.24μg·m~(-3))、Cl-(0.16±0.11μg·m~(-3))、Mg~(2+)(0.11±0.03μg·m~(-3))、Na~+(0.07±0.06μg·m~(-3)); NH_4~+、SO_4~(2-)、NO_3~-是主要水溶性离子,所占比例为83%; NO_3~-/SO_4~(2-)值平均为0.21±0.12,远小于1,说明贵阳秋季PM_(2.5)以固定源污染为主.相关性分析表明,PM_(2.5)中NH_4~+主要以(NH_4)_2SO_4、NH_4HSO_4、NH_4NO_3的形式存在,Ca~(2+)与Mg~(2+)来源可能相同.结合富集系数分析NO_3~-、SO_4~(2-)、Ca~(2+)、K~+、Mg~(2+)基本都是来源于陆源贡献,NO_3~-、SO_4~(2-)是人为源,Ca~(2+)、K~+、Mg~(2+)是地壳源,此外Mg~(2+)还有一部分海源贡献.  相似文献   

10.
为分析菏泽市大气颗粒物及其水溶性离子组分特征,本研究于2015年8月期间在菏泽市6个监测点位采集环境受体PM_(10)和PM_(2.5)样品共120个,利用离子色谱法测定颗粒物中水溶性无机离子(SO■、NO~-_3、NH~+_4、Cl~-、Ca~(2+)、K~+、Na~+、Mg~(2+)、F~-),并同步收集气象参数及气态污染物质量浓度等资料.结果表明,菏泽市夏季环境受体中颗粒物质量浓度ρ(PM_(10))和ρ(PM_(2.5))分别为94.5μg·m~(-3)、55.2μg·m~(-3),稍低于国内其他城市,这与各城市经济发展、产业能源结构、气象条件等因素有关.PM_(2.5)/PM_(10)值在0.5—0.8之间,表明菏泽市夏季细颗粒物(PM_(2.5))污染较为严重.但PM_(10)和PM_(2.5)中水溶性离子质量总浓度ρ(WSIs)分别为30.5μg·m~(-3)、17.0μg·m~(-3);质量分数w(WSIs)分别为32.4%、29.6%.其中SO■、NO~-_3、NH~+_4为PM_(10)和PM_(2.5)中主要水溶性离子,3种离子浓度和分别占PM_(10)和PM_(2.5)中总离子浓度的84.3%、88.3%.SO■、NO~-_3、NH~+_4、K~+主要集中在细颗粒物(PM_(2.5))中,Ca~(2+)、Mg~(2+)则广泛存在于粗颗粒物(PM_(10))中.各采样点的PM_(10)和PM_(2.5)中,SO■、NO~-_3、NH~+_4、Ca~(2+)和Mg~(2+)浓度分布具有空间差异.离子相关性表明,NH~+_4与SO■、NO~-_3相关性均较强,3种离子主要以NH_4HSO_4、NH_4NO_3形式存在.PM_(10)和PM_(2.5)中NO~-_3/SO■值分别在0.41—0.49和0.36—0.47之间,平均值分别为0.46、0.42,表明固定源是菏泽市夏季颗粒物污染的主要污染贡献源.  相似文献   

11.
A bioblitz inexpensively and quickly generates biodiversity data, but bioblitzes are often conducted with haphazard, unreplicated sampling. Results tend to be taxonomically, geographically, or temporally biased, lack metadata, and consist of lists of observed taxa that do not enable further analyses or correction for imperfect detection. A rapid, recurring, structured survey (RRSS) uses a structured sampling design and temporal and spatial replication to survey randomly selected sites on a conservation property. We participated in a loosely structured bioblitz and a subsequent RRSS at Big Canoe Creek Nature Preserve in Springville (St. Clair County), Alabama (USA) to compare observed richness derived from the 2 survey approaches. The RRSS data structure enabled us to fit models that accounted for imperfect detection to estimate abundances, occupancy probabilities, and habitat associations. The loosely structured bioblitz data could not be used in such models. We present a new integrated multispecies abundance model that we applied to avian RRSS data. Our model extension enables estimation for the community, employs data augmentation to estimate the number of undetected species, and incorporates covariates. The RRSS generated a more comprehensive and less biased list of observed taxonomic richness than the loosely structured bioblitz (e.g., 73 vs. 45 bird species and 104 vs. 63 insect families from the RRSS vs. loosely structured bioblitz, respectively). Models fit to the RRSS data identified seasonal patterns in avian community composition and allowed for estimation of habitat–occupancy relationships for insect taxa. The RRSS protocol has potential for broad transferability as a standardized, quick, and inexpensive way to inventory biodiversity and estimate ecological parameters while providing an outreach opportunity.  相似文献   

12.
Land-use change via human development is a major driver of biodiversity loss. To reduce these impacts, billions of dollars are spent on biodiversity offsets. However, studies evaluating offset project effectiveness that examine components such as the overall compliance and function of projects remain rare. We reviewed 577 offsetting projects in freshwater ecosystems that included the metrics project size, type of aquatic system (e.g., wetland and creek), offsetting measure (e.g., enhancement, restoration, and creation), and an assessment of the projects’ compliance and functional success. Project information was obtained from scientific and government databases and gray literature. Despite considerable investment in offsetting projects, crucial problems persisted. Although compliance and function were related to each other, a high level of compliance did not guarantee a high degree of function. However, large projects relative to area had better function than small projects. Function improved when projects targeted productivity or specific ecosystem features and when multiple complementary management targets were in place. Restorative measures were more likely to achieve targets than creating entirely new ecosystems. Altogether the relationships we found highlight specific ecological processes that may help improve offsetting outcomes.  相似文献   

13.
Protected areas (PAs) are often implemented without consideration of already existing PAs, which is likely to cause an overrepresentation of certain biophysical conditions. We assessed the representativeness of the current PA network with regard to the world's biophysical conditions to highlight which conditions are underprotected and where these conditions are located. We overlaid terrestrial and marine PAs with information on biophysical conditions (e.g., temperature, precipitation, and elevation) and then quantified the percentage of area covered by the PA network. For 1 variable at a time in the terrestrial realm, high temperature, low precipitation, and medium and very high elevation were underrepresented. For the marine realm, low and medium sea surface temperature (SST), medium and high sea surface salinity (SSS), and the deep sea were underrepresented. Overall, protection was evenly distributed for elevation across the terrestrial realm and SST across the marine realm. For 2 variables at a time, cold and very dry terrestrial environments had mostly low protection, which was also the case for low SST and low and medium SSS across most depths for marine environments. Low protection occurred mostly in the Sahara and the Arabian Peninsula for the terrestrial realm and along the Tropic of Capricorn and toward the poles for the marine realm. Although biodiversity measures are of prime importance for the design of PA networks, highlighting biophysical gaps in current PAs adds a frequently overlooked perspective. These gaps may weaken the potential of PAs to conserve biodiversity. Thus, our results may provide useful insights for researchers, practitioners, and policy makers to establish a more comprehensive global PA network.  相似文献   

14.
Summary The adaptation of defensive secretions to their target organisms was examined for the abdominal gland secretions ofBledius furcatus, B. spectabilis andB. arenarius. Therefore the target organisms of the secretion of theseBledius species (i.e. their predators) had to be identified. At the collection sites examined these were the earwigLabidura riparia, the antCataglyphis bicolor, the flyLispe candicans, different carabids of the generaPogonus, Dichirotrichus, Dyschirius, Bembidion andCalathus and the wading birdsHaematopus ostralegus andCalidris alba. The secretion of the abdominal glands contains the toxin ptoluquinone dissolved in either-dodecalactone and 1-undecene (B. furcatus andB. spectabilis) or in octanoic acid and octyloctanoate (B. arenarius). The ratio of these solvents is species-specific. Application experiments using some of the natural insect predators (L. riparia, C. bicolor, Pogonus, Di. gustavii, Dyschirius) revealed that these solvent ratios provided a more effective deterrent than other possible ratios. Thus by combining the solvents in certain ratios, the capability of cuticular penetration and therefore the effectiveness of the defensive secretions are adapted to their natural targets.  相似文献   

15.
The politics of development includes subtexts of choice, as underpinned by community consensus (or lack of it), against the larger backdrop of a liberal democracy, with its intricate power structures that influence the choice of concepts and often lead to complicity rather than consent. A dilemma exists between the understanding of field-level practitioners and that of academics, whose understandings of progress differ. Progress can (and often does) imply long-term change across generations whereas development is often more a matter of crisis management and delivering tangible results to end-users. This makes it a bone of contention across political systems, irrespective of local or global dynamics. Development can emerge as a tool to be wielded for power and further political mileage at the expense of progress. Progress cannot be studied as a counterpoint to development as the sense of history is often missing in development interventions. Development tends to be piecemeal as its very logic often stems from the rationale of power. This is not to suggest, however, that development is only about politics; it is definitely more than the politics of everyday life and involves all of civil society that requires its critical and immediate attention. In this sense, it has become a priority for politicians with an underlying agenda designed to out-manouevre dissent and all statements of protest.  相似文献   

16.
An argument is presented in which areas of natural arsenic contamination of modern groundwaters throughout Asia have a common origin. Arsenic originally accumulated in oceanic ferro-manganoan sediments of the eastern Palaeo-Tethys. This was further concentrated through oceanic crustal extinction in what later became the south-east Chinese accreted mineralised terrain. Proto-Himalayan uplift of this area created the palaeo-drainage systems of the Ganges – Brahmaputra, Irrawaddy, Mekong, and Red Rivers, with consequent headwater erosion of arsenic-rich sediments. Their downstream deposition as immature and easily redistributed Neogene sandstones, silts, and iron-rich clays has created secondary and tertiary reservoirs of adsorbed and authigenic arsenic, from which the current arsenic-rich groundwaters have evolved. Considering river basins within the above palaeo-hydrogeological framework provides a basis for assessing the risk of arsenic in groundwater basins of south and south-eastern Asia.  相似文献   

17.
As landscapes continue to fall under human influence through habitat loss and fragmentation, fencing is increasingly being used to mitigate anthropogenic threats and enhance the commercial value of wildlife. Subsequent intensification of management potentially erodes wildness by disembodying populations from landscape-level processes, thereby disconnecting species from natural selection. Tools are needed to measure the degree to which populations of large vertebrate species in formally protected and privately owned wildlife areas are self-sustaining and free to adapt. We devised a framework to measure such wildness based on 6 attributes relating to the evolutionary and ecological dynamics of vertebrates (space, disease and parasite resistance, exposure to predation, exposure to limitations and fluctuations of food and water supply, and reproduction). For each attribute, we set empirical, species-specific thresholds between 5 wildness states based on quantifiable management interventions. We analysed data from 205 private wildlife properties with management objectives spanning ecotourism to consumptive utilization to test the framework on 6 herbivore species representing a range of conservation statuses and commercial values. Wildness scores among species differed significantly, and the proportion of populations identified as wild ranged from 12% to 84%, which indicates the tool detected site-scale differences both among populations of different species and populations of the same species under different management regimes. By quantifying wildness, this framework provides practitioners with standardized measurement units that link biodiversity with the sustainable use of wildlife. Applications include informing species management plans at local scales; standardizing the inclusion of managed populations in red-list assessments; and providing a platform for certification and regulation of wildlife-based economies. Applying this framework may help embed wildness as a normative value in policy and mitigate the shifting baseline of what it means to truly conserve a species.  相似文献   

18.
How should managers choose among conservation options when resources are scarce and there is uncertainty regarding the effectiveness of actions? Well‐developed tools exist for prioritizing areas for one‐time and binary actions (e.g., protect vs. not protect), but methods for prioritizing incremental or ongoing actions (such as habitat creation and maintenance) remain uncommon. We devised an approach that combines metapopulation viability and cost‐effectiveness analyses to select among alternative conservation actions while accounting for uncertainty. In our study, cost‐effectiveness is the ratio between the benefit of an action and its economic cost, where benefit is the change in metapopulation viability. We applied the approach to the case of the endangered growling grass frog (Litoria raniformis), which is threatened by urban development. We extended a Bayesian model to predict metapopulation viability under 9 urbanization and management scenarios and incorporated the full probability distribution of possible outcomes for each scenario into the cost‐effectiveness analysis. This allowed us to discern between cost‐effective alternatives that were robust to uncertainty and those with a relatively high risk of failure. We found a relatively high risk of extinction following urbanization if the only action was reservation of core habitat; habitat creation actions performed better than enhancement actions; and cost‐effectiveness ranking changed depending on the consideration of uncertainty. Our results suggest that creation and maintenance of wetlands dedicated to L. raniformis is the only cost‐effective action likely to result in a sufficiently low risk of extinction. To our knowledge we are the first study to use Bayesian metapopulation viability analysis to explicitly incorporate parametric and demographic uncertainty into a cost‐effective evaluation of conservation actions. The approach offers guidance to decision makers aiming to achieve cost‐effective conservation under uncertainty.  相似文献   

19.
Abstract: In the United States, as elsewhere, a growing debate pits national energy policy and homeland security against biological conservation. In rural communities the extraction of fossil fuels is often encouraged because of the employment opportunities it offers, although the concomitant itinerant workforce is often associated with increased wildlife poaching. We explored possible positive and negative factors associated with energy extraction in the Greater Yellowstone Ecosystem (GYE), an area known for its national parks, intact biological diversity, and some of the New World's longest terrestrial migrations. Specifically, we asked whether counties with different economies—recreation (ski), agrarian (ranching or farming), and energy extractive (petroleum)—differed in healthcare (gauged by the abundance of hospital beds) and in the frequency of sexual predators. The absolute and relative frequency of registered sex offenders grew approximately two to three times faster in areas reliant on energy extraction. Healthcare among counties did not differ. The strong conflation of community dishevel, as reflected by in‐migrant sexual predators, and ecological decay in Greater Yellowstone is consistent with patterns seen in similar systems from Ecuador to northern Canada, where social and environmental disarray exist around energy boomtowns. In our case, that groups (albeit with different aims) mobilized campaigns to help maintain the quality of rural livelihoods by protecting open space is a positive sign that conservation can matter, especially in the face of rampant and poorly executed energy extraction projects. Our findings further suggest that the public and industry need stronger regulatory action to instill greater vigilance when and where social factors and land conversion impact biological systems.  相似文献   

20.
Summary Acanthoscelides obtectus (Say) is one of the most damaging pests of kidney beans,Phaseolus vulgaris L. worldwide. However, aromatic plants from the families Lamiaceae, Lauraceae, Myrtaceae and Poaceae can protect kidney beans by direct or delayed insecticidal effect, through increased adult mortality and inhibition of beetle reproduction (both oviposition and adult emergence). The efficiency of hydrodistillated and intact plants fromThymus vulgaris andT. serpyllum, Mentha piperata, Rosmarinus officinalis, Satureia hortensis, Eucalyptus globulus, Laurus nobilis, Origanum vulgare, andCymbopogon nardus was compared. For both extracts,Origanum vulgare had the best effect. The insecticidal effect was induced by more than the essential oils because no significant difference was noticed between distilled and intact plants extract. Inhibition of reproduction was particularly important. These results suggest that lipidic as well as non lipidic, allelochemicals, such as phenolics, or non-protein amino-acids, or flavonoids may be involved in the toxicity of aromatic plants to this beetle.  相似文献   

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