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271.
272.
The Australian buprestid beetle Merimna atrata (Coleoptera: Buprestidae) approaches forest fires because its larvae develop in freshly burnt wood. So far nothing is known
about possible sensory systems enabling the beetles to detect fires and to cope with the thermal environment close to the
flames. We found that M. atrata has two pairs of infrared (IR) organs on the ventrolateral sides of the abdomen. Each IR organ consists of a specialized
IR-absorbing area which is innervated by one thermosensitive multipolar neuron. The primary dendritic branches ramify into
more than 800 closely packed terminal endings which contain a large number of mitochondria. We called the special morphology
of the dendritic region a terminal dendritic mass. The type of IR receptor found in M. atrata is unique in insects and can best be compared with the IR organs of boid snakes.
Received: 14 August 2000 / Accepted in revised form: 18 October 2000 相似文献
273.
274.
IntroductionTheuseofchemicals,includingpesticides,hasbecomeanintegralandeconomicallyessentialpartofmodernagriculture.Pesticide?.. 相似文献
275.
Laperdina T. G. Melnikova M. V. Koval A. T. Sidorov Y. F. Nagorny V. A. Ostapchuk V. I. 《环境科学学报(英文版)》2000,(Z1)
IntroductionSiberiaandtheFarEastaretheoldestandtherichestgold miningareasofRussia .Intensivegold miningherestartedinthebeginningofthe 19thcentury(Vyazelshchikov ,1963) .Forthemostpartgold bearingoresandsandswereprocessedwiththeuseofamalgamationmethodforgolde… 相似文献
276.
<正> 在过去的年代里,矿石、矿物、土壤、沉积物、灰份以及玻璃、颜料等制造品中的主量、少量、甚至痕量元素的测定都是用经典重量法、滴定法和分光光度法完成的。近几十年来,经典方法已经大量地被X-射线萤光、原子吸收光谱电弧发射光谱和质子诱发的X-射线分析等多种仪器方法所代替。 相似文献
277.
The province of Huelva in the SW of Spain presents high environmental contrasts: together with the great abundance of natural spaces, it shows the impacts of historical natural resources exploitation processes. In the Ria of Huelva, the effluents of the chemical industries must be added to the contaminating inputs of the Tinto and Odiel rivers, coming from the acid drainage of the mines located in the Iberian Pyrite Belt. This forced the Environmental Agency (AMA) to elaborate in 1987 an Effluent Remediation Plan in order to negate unacceptable environmental impacts. The application of a grey box systemic analysis to the AMD pollution, undergone by the Tinto and Odiel rivers has allowed to set a conclusive explanation of the sampling results observed for a period of 11 years, thus making available an overall view of the polluting process and, above all, an explanation of its partial aspects. 相似文献
278.
Srivastava A Joseph AE More A Patil S 《Environmental monitoring and assessment》2005,109(1-3):227-242
Air pollution has assumed gigantic proportion killing almost half a million Asians every year. Urban pollution mainly comprises
of emissions from buses, trucks, motorcycle other forms of motorized transport and its supporting activities. As Asia's cities
continue to expand the number of vehicles have risen resulting in greater pollution. Fugitive emissions from retail distribution
center in urban area constitute a major source. Petrol vapours escape during refueling adding pollutants like benzene, toluene,
ethylbenzene and xylene to ambient air. This paper discusses a study on fugitive emissions of Volatile Organic Compounds (VOC)
at some refueling station in two metropolitan cities of India, i.e., Mumbai and Delhi. Concentration of VOCs in ambient air
at petrol retail distribution center is estimated by using TO-17 method. Concentration of benzene in ambient air in Delhi
clearly shows the effect of intervention in use of petroleum and diesel fuel and shift to CNG. Chemical Mass Balance (CMB)
model is used to estimate source contributions. At Delhi besides diesel combustion engines, refueling emissions are also major
sources. At Mumbai evaporative emissions are found to contribute maximum to Total VOC (TVOC) concentration in ambient air. 相似文献
279.
Mohammed A 《Environmental monitoring and assessment》2005,104(1-3):37-44
The toxicity of the water-soluble fraction (WSF) of four fuels (leaded gasoline, unleaded gasoline, diesel, Jet A-1) to Metamysidopsis insularis, an indigenous tropical mysid species was determined. Approximately 10 000 barrels (bbl) of fuel are consumed daily in Trinidad and Tobago, and about 50 000 bbl are exported. Accidental discharges at points of transfer as well as from inadequate storage facilities, can pose a significant contamination risk to the environment. Organisms were assayed with the WSF under both UV and fluorescent lights. The WSF was prepared using different fuel/seawater (v/v) mixtures. It was found that organisms exposed to diesel, Jet A-1 and unleaded gasoline showed similar toxicological responses under both light regimes, and were more toxic than the leaded gasoline. The results also showed that none of these fuels show photo-induced toxicity. The WSF of the 0.1% mixtures of unleaded gasoline, diesel and Jet A-1 were acutely toxic to M. insularis. However, for the leaded gasoline, only the 0.5% mixture was acutely toxic. The high toxicity of these fuels may be due to the presence of light, more soluble fractions. It is therefore likely that these fuels will have significant impacts in our local environment, if any spills occur. 相似文献
280.
Landsat 7s recent malfunctioning will result in significant gaps in long-term satellite monitoring of Earth, affecting not only the research of the Earth science community but also conservation users of these data. To determine whether or how important Landsat monitoring is for conservation and natural resource management, we reviewed the Landsat programs history with special emphasis on the development of user groups. We also conducted a bibliographic search to determine the extent to which conservation research has been based on Landsat data. Conservation biologists were not an early user group of Landsat data because a) biologists lacked technical capacity – computers and software – to analyze these data; b) Landsats 1980s commercialization rendered images too costly for biologists budgets; and c) the broad-scale disciplines of conservation biology and landscape ecology did not develop until the mid-to-late 1980s. All these conditions had changed by the 1990s and Landsat imagery became an important tool for conservation biology. Satellite monitoring and Landsat continuity are mandated by the Land Remote Sensing Act of 1992. This legislation leaves open commercial options. However, past experiments with commercial operations were neither viable nor economical, and severely reduced the quality of monitoring, archiving and data access for academia and the public. Future satellite monitoring programs are essential for conservation and natural resource management, must provide continuity with Landsat, and should be government operated. 相似文献