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11.
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Holt SJ 《Marine pollution bulletin》2007,54(8):1081-1086
It is argued that Japan’s authorities and entrepreneurs involved in whaling and the whale-meat trade have a long-term goal of rebuilding a large and profitable industry of pelagic whaling, particularly in the Southern Hemisphere, in the next 20 years or so. They have made large investments in this enterprise since the so-called moratorium on commercial whaling was adopted by the International Whaling Commission in 1982. These include, but are not confined to, state subsidizing of an expanding and diversifying 20-year programme of commercial whaling under provisions in all relevant international agreements since 1937 that permit unlimited and unilaterally decreed whaling, supposedly for scientific purposes, provided that the commodities from the whales killed are fully utilized. The context of this is the monopoly of technical knowledge, special skills and the market for valuable whale-meat that Japanese enterprises acquired in the post-world war II period, having broken - in 1937 - the strongly defended de facto Anglo-Norwegian monopoly of technology, skills, access to Antarctic whaling grounds and the market for whale-oil that had existed until then. The attraction of ‘scientific whaling’ is not only that it by-passes any internationally agreed catch-limits but that it also circumvents all other rules - many dating fr/om the League of Nations whaling convention of 1931 - regarding protected species, closed areas, killing of juveniles, less inhumane killing methods, etc. The groundwork is being laid to justify that resumed whaling on partially recovered whale stocks will be at the unsustainable levels that will be profitable again. This justification is based on spurious assertions that numerous and hungry whales threaten the world’s fisheries, and that the abundance and possible increase in some whale species is impeding the recovery of other, severely depleted, and potentially more valuable species such as the blue whale. If the scenario presented here is correct it has important implications for attempts by the international community either to bring a negotiated end to commercial whaling or to bring all whaling back under international control, as the international law of the sea requires, and to ensure that any permitted exploitation of recovered whale populations will be sustainable, under a precautionary regime. 相似文献
14.
We conducted studies to determine if the xenoestrogens Surflan and its active ingredient oryzalin, affect indices of reproductive fitness in medaka (Oryzias latipes). Oryzalin (0.5, 0.25mg/l) or Surflan (2.0 microl/l) and oryzalin (0.5mg/l) significantly increased the mean number of non-fertilized eggs produced by treated females paired with untreated males, or by untreated females paired with treated males. Oryzalin (1.0, 0.5, 0.25mg/l) and Surflan (3.8, 2.0, 1.0 microl/l) significantly affected the time to hatch of eggs from treated females paired with untreated males, and from untreated females paired with treated males. Surflan (3.8, 2.0, 1.0 microl/l) induced intersex lesions in 80-100% of males. Oryzalin-exposed males exhibited a significant increase in the incidence of necrotic spermatids and necrotic spermatogonia, while oryzalin-exposed females had significantly fewer immature oocytes and an increase in the occurrence of hyperplastic ovaries. Our results indicate that Surflan and oryzalin affect both reproduction and gonadal histology in male and female medaka. 相似文献
15.
通过对2009—2012年度临沂市9县3区统计年鉴和变更调查中11个相关指标数据的搜集,借助 MATLAB7.0软件平台,利用 BP 人工神经网络算法,算出2009—2012年度各县区土地利用集约度,并利用 BP 人工神经网络的预测功能,预测了2013年和2014年度土地利用集约度值,结果表明临沂市平均土地利用集约度水平正逐步从粗放利用发展到中度集约,兰山区土地利用集约度水平一直为高度集约,集约度居全市之首,罗庄区一直为中度集约,稳中有进。预计到2014年底,大部分县区在中度集约或以上,仅有费县、蒙阴2县为粗放利用。。 相似文献
16.
黄土/古土壤的物源研究对于揭示第四纪气候变化和青藏高原隆升历史具有重要意义。本研究以位于黄土高原西部1.4 Ma以来的兰州黄土/古土壤沉积序列为研究对象,基于X射线衍射技术分析了黄土/古土壤中的主要矿物组成,侧重于碳酸盐矿物含量,追溯了兰州黄土/古土壤的直接物源。结果显示: (1)1.4 Ma以来兰州地区黄土/古土壤沉积物的主要直接源区为柴达木盆地沙漠区和阿拉善干旱区。(2)基于二元混合模型计算的潜在原始源区对兰州黄土白云石和总碳酸盐矿物的相对贡献率以及长石与石英比值结果一致支持1.4 Ma以来兰州黄土原始物源发生了多次变化。1.4~1.1 Ma和0.9~0.3 Ma青藏高原东北缘造山带(昆仑山、祁连山)和中亚造山带对兰州黄土的贡献相当,而1.1~0.9 Ma和0.3 Ma以来,中亚造山带对兰州黄土的物源贡献增加,这可能分别是对中更新世气候转型和0.3 Ma以来青藏高原及邻近地区干冷气候增强的响应。1.15 Ma和0.8 Ma兰州黄土/古土壤中高的白云石含量、碳酸盐矿物总含量以及0.8 Ma长石与石英比值的快速升高可能是对“昆黄运动”的响应,进而造成了昆仑山、祁连山对黄土高原物源贡献的增加。 相似文献
17.
二道泉剖面(39°01′34″N,95°52′49″E)位于党河盆地腹地,呈北南向展布,长790 m,党河盆地位于祁连山腹地,是研究青藏高原北部构造沉积与地貌演变的理想地区。本研究在野外地层观测、古流水重建及砾石组分分析的基础上,对党河盆地中西部二道泉剖面新近系白杨河组顶部-玉门砾岩底部河湖相沉积物进行磁化率测量与等温剩磁实验分析。结果显示,剖面沉积物的磁性矿物主要有磁铁矿和赤铁矿,其中赤铁矿相对含量较高。通过对比发现剖面中黄色调粗粒沉积物中的赤铁矿含量显著高于红色调细粒沉积物。砾石成分和向南的古流向结果显示,白杨河组晚期至玉门砾岩早期地层沉积物主要源自于二道泉剖面北部的野马南山地区。磁化率及沉积相揭示出源区物理风化作用逐渐增强,赤铁矿是从源区直接搬运沉积的,而非自生形成;这一过程未受外界气候环境的影响,赤铁矿多为碎屑,岩石颜色发黄。综合分析认为,二道泉剖面疏勒河组到玉门砾岩组早期沉积时党河盆地发育一条规模逐渐变大、水动力逐渐变强的由北向南流动的河流,现今流向为北西向的党河水系可能最早在新近纪玉门砾岩沉积中期以后才形成。 相似文献
18.
Hardman-Mountford NJ Allen JI Frost MT Hawkins SJ Kendall MA Mieszkowska N Richardson KA Somerfield PJ 《Marine pollution bulletin》2005,50(12):1463-1471
Adaptive management of the marine environment requires an understanding of the complex interactions within it. Establishing levels of natural variability within and between marine ecosystems is a necessary prerequisite to this process and requires a monitoring programme which takes account of the issues of time, space and scale. In this paper, we argue that an ecosystem approach to managing the marine environment should take direct account of climate change indicators at a regional level if it is to cope with the unprecedented change expected as a result of human impacts on the earth climate system. We discuss the purpose of environmental monitoring and the importance of maintaining long-term time series. Recommendations are made on the use of these data in conjunction with modern extrapolation and integration tools (e.g. ecosystem models, remote sensing) to provide a diagnostic approach to the management of marine ecosystems, based on adaptive indicators and dynamic baselines. 相似文献
19.
20.
黄土/古土壤的物源研究对于揭示第四纪气候变化和青藏高原隆升历史具有重要意义。本研究以位于黄土高原西部1.4 Ma以来的兰州黄土/古土壤沉积序列为研究对象,基于X射线衍射技术分析了黄土/古土壤中的主要矿物组成,侧重于碳酸盐矿物含量,追溯了兰州黄土/古土壤的直接物源。结果显示: (1)1.4 Ma以来兰州地区黄土/古土壤沉积物的主要直接源区为柴达木盆地沙漠区和阿拉善干旱区。(2)基于二元混合模型计算的潜在原始源区对兰州黄土白云石和总碳酸盐矿物的相对贡献率以及长石与石英比值结果一致支持1.4 Ma以来兰州黄土原始物源发生了多次变化。1.4~1.1 Ma和0.9~0.3 Ma青藏高原东北缘造山带(昆仑山、祁连山)和中亚造山带对兰州黄土的贡献相当,而1.1~0.9 Ma和0.3 Ma以来,中亚造山带对兰州黄土的物源贡献增加,这可能分别是对中更新世气候转型和0.3 Ma以来青藏高原及邻近地区干冷气候增强的响应。1.15 Ma和0.8 Ma兰州黄土/古土壤中高的白云石含量、碳酸盐矿物总含量以及0.8 Ma长石与石英比值的快速升高可能是对“昆黄运动”的响应,进而造成了昆仑山、祁连山对黄土高原物源贡献的增加。 相似文献