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191.
Moving Beyond Strawmen and Artificial Dichotomies: Adaptive Management When an Endangered Species Uses an Invasive One 总被引:1,自引:1,他引:0
Daniel Simberloff 《Journal of Agricultural and Environmental Ethics》2009,22(1):73-80
Evans et al. (Journal of Agricultural and Environmental Ethics, 2008) have attempted to enmesh me in their dispute with the Florida Bureau of Invasive Plant Management about a specific
system, Kings Bay/Crystal River. In so doing, they repeatedly mischaracterize my positions in order to depict, incorrectly,
invasion biology as monolithic and me as a representative of one extreme of a false dichotomy about management of introduced
species. In addition, they introduce an issue irrelevant in this case (extinctions) and cite incorrect data. Proposing to
manage people, manatees, introduced plants, and cyanobacteria in Kings Bay by participative adaptive management, they ignore
the fact that living organisms can both disperse autonomously and hitchhike. Finally, they present few details on any aspect
of their management proposal and do not address the myriad problems that have beset previous attempts at scientific adaptive
management, especially at large scales. Until such a management approach is fleshed out and implemented, it is impossible
to assess its validity for Kings Bay, and it is very premature to suggest it as a general model for dealing with invasive
species disputes. 相似文献
192.
JONATHAN BART ROBERT M. PLATTE BRAD ANDRES STEPHEN BROWN JAMES A. JOHNSON WILLIAM LARNED 《Conservation biology》2013,27(6):1304-1312
We used data from aerial surveys (1992–2010) of >100,000 km2 and ground surveys (1998–2004) of >150 km2 to estimate the density and abundance of birds on the North Slope of Alaska (U.S.A.). In the ground surveys, we used double sampling to estimate detection ratios. We used the aerial survey data to compare densities of birds and Arctic fox (Vulpes lagopus), the major nest predator of birds, on the North Slope, in Prudhoe Bay, and in nearby areas. We partitioned the Prudhoe Bay oil field into 2 × 2 km plots and determined the relation between density of aquatic birds and density of roads, buildings, and other infrastructure in these plots. Abundance and density (birds per square kilometer) of 3 groups of aquatic birds—waterfowl, loons, and grebes; shorebirds; and gulls, terns, and jaegers—were highest in the National Petroleum Reserve–Alaska (NPRA) and lowest in the Arctic National Wildlife Refuge. Six other major wetlands occur in the Arctic regions of Canada and Russia, but the largest population of aquatic birds was in the NPRA. Aquatic birds were concentrated in the northern part of the NPRA. For example, an area that covered 18% of the NPRA included 53% of its aquatic birds. The aerial surveys showed that bird density was not lower and fox density was not higher in Prudhoe Bay than in surrounding areas. Density of infrastructure did not significantly affect bird density for any group of species. Our results establish that the NPRA is one of the most important areas for aquatic birds in the Arctic. Our results and those of others also indicate that oil production, as practiced in Prudhoe Bay, does not necessarily lead to substantial declines in bird density or productivity in or near the developed areas. Prioridades para la Conservación de Aves en el Norte de Alaska 相似文献
193.
J. M. Evans A. C. Wilkie J. Burkhardt 《Journal of Agricultural and Environmental Ethics》2009,22(2):169-180
Our recent paper advocating adaptive management of invasive nonnative species (INS) in Kings Bay, Florida received detailed
responses from both Daniel Simberloff, a prominent invasion biologist, and Mark Sagoff, a prominent critic of invasion biology.
Simberloff offers several significant lines of criticism that compel detailed rebuttals, and, as such, most of this reply
is dedicated to this purpose. Ultimately, we find it quite significant that Simberloff, despite his other stated objections
to our paper, apparently agrees with our argument that proposals for alternative management of established INS (i.e., alternatives
to minimization/eradication) should not be rejected on an a␣priori basis. We argue that more specific development and application
of adaptive approaches toward INS management, whether in Kings Bay or other appropriate case studies, would be facilitated
if ecosystem managers and invasion biologists follow Simberloff’s lead on this key point. While Sagoff largely shares (and,
indeed, served as a primary source for developing) our general arguments that challenge common moral and scientific assumptions
associated with invasion biology, he does question our suggestion that participatory adaptive management provides an appropriate
framework for approaching environmental problems in which science and politics are inherently entangled. We attempt to answer
this criticism through a brief sketch of what participatory adaptive management might look like for Kings Bay and how such
an approach would differ from past management approaches. 相似文献
194.
195.
One of the chemical breakdown products of nonylphenol ethoxylates, 4-nonylphenol (4-NP), accumulates in organisms and is of concern as an environmental pollutant due to its endocrine disrupting effects. We measured 4-NP levels in the seawater, sediment, and twelve organisms within the California estuary, Morro Bay, and examined biomagnification of 4-NP using stable isotope abundances (δ15N and δ13C) to quantify trophic position. 4-NP concentrations in organisms from Morro Bay included 25000 ± 8600 ng g−1 lw in liver of California sea lion, 14000 ± 5600 ng g−1 lw in liver of harbor porpoise, 138000 ± 55000 ng g−1 lw in liver of sea otters, 15700 ± 3600 ng g−1 lw in liver of seabirds, 36100 ± 6100 ng g−1 lw in arrow goby fish, 62800 ± 28400 ng g−1 lw in oysters, and 12700 ± 1300 ng g−1 lw in mussels. 4-NP levels generally showed a pattern of trophic dilution among organisms in Morro Bay, with exceptions of biomagnification observed between three trophic links: mussel to sea otter (BMF 10.9), oyster to sea otter (BMF 2.2), and arrow goby to staghorn sculpin (BMF 2.7). Our examination of other west coast estuaries of USA and Canada revealed that mean 4-NP concentrations in gobies and mussels from Morro Bay were significantly higher than those from a more urbanized estuary, San Francisco Bay (goby: 11100 ± 3800 ng g−1 lw) and from a remote estuary, Bamfield Inlet, Canada (goby: 9000 ± 900 ng g−1 lw, mussel: 6100 ± 700 ng g−1 lw). Relative to other estuaries worldwide, 4-NP levels in seawater (0.42 ± 0.16 μg L−1) and sediment (53 ± 14 ng g−1 dw) of Morro Bay are low, but gobies and oysters have higher 4-NP levels than comparable fauna. 相似文献
196.
Spatial and temporal distribution of polycyclic aromatic hydrocarbons (PAHs) in sediments from Daya Bay, South China 总被引:2,自引:0,他引:2
Wen Yan Jisong Chi Weixia Huang 《Environmental pollution (Barking, Essex : 1987)》2009,157(6):1823-1830
The spatial and temporal distribution of polycyclic aromatic hydrocarbons (PAHs) has been investigated in Daya Bay, China. The total concentration of the 16 USEPA priority PAHs in surface sediments ranged from 42.5 to 158.2 ng/g dry weight with a mean concentration of 126.2 ng/g. The spatial distribution of PAHs was site-specific and combustion processes were the main source of PAHs in the surface sediments. Total 16 priority PAH concentration in the cores 8 and 10 ranged from 77.4 to 305.7 ng/g and from 118.1 to 319.9 ng/g respectively. The variation of the 16 PAH concentrations in both cores followed the economic development in China very well and was also influenced by input pathways. Some of the PAHs were petrogenic in core 8 while pyrolytic source was dominant in core 10. In addition, pyrolytic PAHs in both cores were mainly from the coal and/or grass and wood combustion. 相似文献
197.
利用2021—2022年Sentinel-2卫星搭载的多光谱成像仪(MSI)遥感数据,通过SNAP遥感软件提供的植被生物物理参数处理模块(Biophysical Processor),反演了苏州消夏湾生态安全缓冲区的5种植被生物物理参数,包括植被吸收光合有效辐射比例(FAPAR)、植被覆盖度(FVC)、叶面积指数(LAI)、冠层叶绿素含量(CCC)和冠层含水量(CWC),开展植被生态环境监测评估研究。结果表明,该生态安全缓冲区2021年建成并投入运行后,植被覆盖度和生物量有所增加,区域植被冠层结构有所改善,植被生物物理参数从一定的角度反映了消夏湾生态安全缓冲区发挥了生态涵养成效。该研究方法能在大尺度上快捷、高效地反演植被生物物理参数,可为通过植被遥感动态监测评估生态安全缓冲区的生态功能提供有益的借鉴。 相似文献
198.
Occurrence and distribution of antibiotics in coastal water of the Bohai Bay, China: impacts of river discharge and aquaculture activities 总被引:9,自引:0,他引:9
Zou S Xu W Zhang R Tang J Chen Y Zhang G 《Environmental pollution (Barking, Essex : 1987)》2011,159(10):2913-2920
The presence of 21 antibiotics in six different groups was investigated in coastal water of the Bohai Bay. Meantime, to illuminate the potential effects caused by the river discharge and aquaculture activities, wastewater from three breeding plants and surface water from six rivers flowing into the Bohai Bay were also analyzed for the selected antibiotics. The result revealed that measured antibiotics in the North Bobai Bay were generally higher than those in the South, highlighting the remarkable effects of high density of human activities on the exposure of antibiotics in environment. The antibiotics found in the six rivers were generally higher than those in the Bohai Bay reflecting the important antibiotics source of river discharge. This study reveals that the high consumption of some antibiotics in aquaculture activities may pose high ecological risk to the bay. 相似文献
199.
辽东湾地区~(137)Cs大气沉降研究 总被引:2,自引:0,他引:2
利用137Cs示踪技术的前提条件是了解137Cs的大气沉降历史,从而准确求算区域环境中137Cs的背景值.本文利用日本秋田、东京及新泻地区137Cs年沉降数据,并结合相应的降水数据进行修正,对辽东湾地区137Cs的大气沉降进行了定量研究.结果表明,辽东湾地区137Cs的大气沉降趋势与北半球基本一致;1957—2008年辽东湾地区137Cs大气总沉降通量的模拟结果为1536 Bq·m-2(衰变校正至2009年),与该地区土壤中137Cs背景值较为接近;20世纪50年代末60年代初频繁的大气核试验和1986年的切尔诺贝利核事故是1963年和1986年两个137Cs沉降峰值产生的原因;1990年以后,沉降在地表的137Cs在风力侵蚀作用下,发生再悬浮,使得大气中137Cs沉降通量再次出现量级变化明显.福岛核事故产生的核素沉降对研究区的137Cs沉降通量的影响并不明显. 相似文献
200.
广西钦州湾营养状况季节分析与评价研究 总被引:2,自引:0,他引:2
根据2009年1月、4月、8月和11月对钦州湾海域调查结果,分析并评价了该海域营养状况的季节变化。结果表明,钦州湾海域总溶解无机氮(DIN)含量范围在0.023 mg/L~1.750 mg/L,硅酸盐(SiO3-Si)含量范围在0.027 mg/L~3.900 mg/L,磷酸盐(PO4-P)含量范围在0.001 mg/L~0.158 mg/L。NO3-N是DIN的主要存在形式,占62%~78%。不同的营养盐季节分布有所差异。DIN季节分布表现为夏季春季秋季冬季;PO4-P季节分布为春季秋季冬季夏季;SiO3-Si季节变化为夏季秋季春季冬季。从营养结构看,与Justic'等提出的营养盐化学计量限制标准比较符合P限制条件,PO4-P可能成为浮游植物生长的潜在限制因子。按照营养状态指数值,钦州湾海域春季、夏季和秋季表层海水处于富营养化状态,钦州湾内湾富营养化程度高,一旦水文气象条件适宜,从春季到秋季该区域随时都会发生赤潮灾害的可能。 相似文献