Species decline

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  • A preliminary study was carried out in mid 1999 on the status and potential impact of the introduction of exotic fish species in the Mekong Basin. Introductions have been made for four main purposes: aquaculture, stocking into lakes and reservoirs, pest control (mosquito) and the aquarium fish trade. Introductions of exotic species and movements of large quantities of fish for stocking are accompanied by risks to the environment, the possibility of native fish species declining through competition, predation or genetic interference, and the possible spread of disease....

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  • Conserving Living Natural Resources provides students, managers, and general readers with an introduction to the principles of managing biological resources. It presents the historical and conceptual contexts of three seminal approaches to the management of living natural resources: utilitarian management for harvest of featured species and control of unwanted species, protection and restoration of populations and habitats to maintain biodiversity, and management of complex ecosystems to sustain both productivity and biodiversity.

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  • Students should note that Congress generally prohibits the use of appropriated funds to employ non-citizens within the United States. That restriction is discussed on the USAJobs Web site. Students who are not U.S. citizens are eligible for the student observer program. However, they should recognize that they are generally not eligible to be hired as employees after graduation. We have a limited number of slots and cannot hire all of the students who would be successful interns. Students are welcome to decline our offers.

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  • He discovered that the firm’s fundamental factors exercise the most significant impact on stock prices. The EPS was found to be the most influencing factor over the market. Studying the effects of the Iraq war on US financial markets, Rigobon and Sack (2004) discovered that increases in war risk caused declines in Treasury yields and equity prices, a widening of lower-grade corporate spreads, a fall in the dollar, and a rise in oil prices. A positive correlation exists between the price of oil and war. They argue that war has a significant impact on the oil price.

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  • A put option allows the investor to return the bond, at a price of par, to the issuer prior to its stated maturity. Here, the investor owns the option. Investors will exercise this right when interest rates have risen, since they can reinvest the proceeds at higher available market yields. The put option thus limits price declines when rates rise, because the investor can redeem the bond at par on a specified date. When interest rates fall, however, the price of the security will rise like a bond without option features. Put...

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  • Acid neutralizing capacity (ANC) is a com- monly used chemical indicator of lake or stream sensitivity to acidification. ANC, mea- sured in microequivalents per liter (µeq/L; See Box 3 for a list of chemical units of measure), characterizes the ability of water to neutralize strong acids including those introduced by atmospheric deposition. ANC is a good gen- eral indicator of acidity-related water quality because values are typically strongly correlated with pH, Al +3 concentrations, and Ca +2 con- centrations.

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  • Commencement data  from Australian Education  International  (AEI)  for  the year‐to‐date  to  June 2010, show a decline  in overall commencements  in the onshore  international sector of  around 6.3% on a year on year basis, although higher education is still trending positive with  commencements  to  June of 54,326, up 5.64% on  the 2009 equivalent  figure of 51,339. The  other three key sectors have all seen a marked decline  in enrolments: VET commencements  to June 2010 were at 67,046, down by 4.

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  • Intuitively, the state of the business cycle can influence bank equity prices through its impact on bank assets. During an economic boom, default rates for loans to households and firms decline. This, in turn, boosts bank earnings and can mitigate investors’ perception of the risk in bank profits, thereby lowering their required return on bank stocks. Recessions have the opposite impact on loan values and bank earnings, thereby raising required returns. In fact, the impact is arguably asymmetric.

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  • The authors and contributors to this report acknowledge the Indigenous Traditional Owners of Country throughout Northern Australia, and their right to speak for Country. The authors are recipients of an ARC Linkage Grant focused on investigating connectivity conservation issues in various regions, including Northern Australia. Some of the outcomes from that research were drawn upon for this report.

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  • Adolescent fertility rates are high in many Pacific countries, with little decline in the past decade. For example, between 8-26% of girls aged 15-19 who are married or in civil unions have already started childbearing, and 17 and 62% of recent births were unplanned. This reflects that adolescent pregnancy in the Pacific often occurs outside of marriage and is commonly unintended.

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  • Primary olfactory neuronal cultures exposed to odorant stimulation have previously exhibited concentration-related effects in terms of intracellular cAMP levels and adenylate cyclase activity [Ronnett, G.V., Parfitt, D.J., Hester, L.D. & Snyder, S.H. (1991)PNAS88, 2366–2369].Maximal sti-mulation occurred for intermediate concentrations, whereas AC activity declined for both low and high odorant con-centrations.We suspected that this behavior might be ascribed to the intrinsic response of the first molecular species concerned by odorant detection, i.e. the olfactory receptor itself....

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  • Carmago et al. (1992) found that the rivers nearer industrial discharge point have adverse impact to the environment as well as to macrobenthic communities. Toxic contaminants from surface runoff, sewage discharges and industrial discharge have caused negative impacts towards the freshwater macrobenthic communities. The presence of substance chemical such as ammonia, chlorine, cyanide, metals, PCBs, pesticides and phenols would caused a decline pattern on the number of species and changes in the species composition.

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  • The feedback from oil prices to economic activity is captured by a reduced-form production function that allows us to separately specify shocks to the output gap (transitory shocks to output), shocks to potential output (permanent shocks to the level of output), and shocks to potential output growth (permanent shocks to the growth rate of output). The richness of this specification helps us to model the complicated interactions of oil price movements and GDP, where both trend and gap decline if oil prices increase.

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  • absolute pollen frequency (APF) *Pollen data from sediments, expressed in terms of the absolute numbers for each *species, *genus, or *family, per unit volume of sedi- ment and, where deposition rates are known, per unit time. In certain circumstances this approach gives clearer information than does the traditional way of expressing pollen data as *relative pollen frequencies (RPFs). APFs are particularly useful in site comparisons in which one or more high pollen producers vary.

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  • Decreases in pH and ANC are often paral- leled by changes in element concentrations including increases in Al +3 concentrations and decreases in Ca +2 . High dissolved Al +3 concen- trations can have toxic effects on many types of aquatic biota, and at extreme levels few aquatic species can survive (Table 1). Organic forms of Al +3 are much less toxic than inorganic forms. Emerging research suggests that Ca +2 concentra- tions in streamwater are also an important bio- logical indicator.

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  • Factors thought to have contributed to the decline of the endangered suckers include degradation of spawning habitat, deterioration in the quality of water in Upper Klamath Lake, overexploitation by commercial and noncommercial fishing (now regulated), introduction of competitive or predaceous exotic species, bloc

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  • After creating toxic hazardous chemicals, society has followed an unsustainable course in using and disposing of toxins. More and more sites are being contaminated, cancer rates are rising, indoor air quality has declined to become often more contaminated than outdoor air, and toxic chemicals continue to be found in species as far away from civilization as the Arctic Circle. This chapter provides knowledge of hazardous chemicals: pollution and preventi.

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  • Fewer fish exacerbate the declines in walrus and seal populations. Overall, there is less food available for the Yupik Eskimos of the Arctic who rely on all of these species. Global climate change is thus a significant addition to the spectrum of envi- ronmental health hazards faced by humankind. The global scale makes for unfa- miliarity—although most of its health impacts comprise increases (or decreases) in familiar effects of climatic variation on human biology and health.

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