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T. Szegletes CS. Polyhos T. Bálint A. A. Rady G. Lang O. Kufcsák J. Nemcsók 《Environmental monitoring and assessment》1995,35(2):97-111
Thein vivo effects of deltamethrin (DM) on the blood sugar level, the acetylcholinesterase (AChE, EC 3.1.1.7) activities of the blood serum and various organs (heart, liver and intestine), the lactate dehydrogenase (LDH, EC 1.1.2.3), glutamic-oxaloacetic transaminase (GOT, EC 2.6.1.1), and glutamic-pyruvic transaminase (GPT, EC 2.6.1.2) activities of the blood serum, the adenosine triphosphatases (EC 3.6.1.3; Na+/K+-ATPase and Mg2+-ATPase) activities of the erythrocyte plasma membrane and the catalase (EC 1.11.1.6) activity of the liver were examined throughout 96 h in adult carp (Cyprinus carpio L.) Two sublethal concentrations, 1.0 and 1.5 µg/l of deltamethrin, were used. All fish survived the experiment except one, in an aquarium containing 1.5 ppb of DM, which died after 72 h.The AChE specific activity was significantly inhibited in the heart and intestine after 96 h at both concentrations compared to that in the control animals (P<0.05, Student'st-test), while there was no detectable difference between the two treatment. At the same time there was no detectable change in the liver. In the serum, the AChE activity almost remained unchanged; the only significant decrease could be measured after 96 h at 1.5 µg/l deltamethrin concentration. The blood glucose content exhibited interesting changes: after 24 h fish exposed at 1 µg/l DM seemed to be stressed, although this increase was not significant. When these fish became used to the new conditions (in practice this meant the presence of DM), the glucose level decreased, especially after 72 h. At the same time the control animals kept in similar circumstances showed a small insignificant decrease. Meanwhile fish in aquaria containing 1.5 µg/l DM reacted to the treatment with an increased blood glucose level after 48 h, and this did not change until the end of the treatment. The Na+/K+-ATPase activity decreased in a dose-dependant manner, while Mg2+-ATPase was less affected. A small increase in LDH level was observed, indicating damage of different muscle tissues. However, this phenomenon appeared only with the small dosage after 24 h (P<0.05). It has to be mentioned that the individual values varied to a large extent among of the eight fish.The GOT activities of the serum increased during the treatment. However, significant changes were only expressed after 72 and 96 h at 1 µg/l DM concentrations (P<0.01 andP<0.05), and after a similar long treatment at the high dosage (P<0.05, 72 and 96 h). The GPT did not change significantly in aquaria containing 1 µg/l DM. The only larger increase was measured after 96 h at 1.5 µg/l DM concentration (P<0.05). The catalase activity in the liver of treated carp remained practically at the same level compared to that in control fish.All these changes (concerning the primary effects of this compound) demonstrate the effect of DM on different fish enzymes, at low concentrations under laboratory conditions, which might be useful in practice for biomonitoring using fish. 相似文献
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Focusing on environmental review practice in state departments of transportation in the US, the study examines the practices and effects of stakeholder involvement in scoping processes conducted under the National Environmental Policy Act (NEPA). Based on a survey of environmental review staff in 46 of the 50 states, the study finds variation in approaches used by states and relatively high levels of perceived effectiveness. The findings include a number of internal and external factors that contribute to effectiveness and highlight the impacts of participation on the content and outcomes of scoping processes. 相似文献
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Jordan NR Slotterback CS Cadieux KV Mulla DJ Pitt DG Olabisi LS Kim JO 《Environmental management》2011,48(1):1-12
Increasingly, total maximum daily load (TMDL) limits are being defined for agricultural watersheds. Reductions in non-point
source pollution are often needed to meet TMDL limits, and improvements in management of annual crops appear insufficient
to achieve the necessary reductions. Increased adoption of perennial crops and other changes in agricultural land use also
appear necessary, but face major barriers. We outline a novel strategy that aims to create new economic opportunities for
land-owners and other stakeholders and thereby to attract their voluntary participation in land-use change needed to meet
TMDLs. Our strategy has two key elements. First, focused efforts are needed to create new economic enterprises that capitalize
on the productive potential of multifunctional agriculture (MFA). MFA seeks to produce a wide range of goods and ecosystem
services by well-designed deployment of annual and perennial crops across agricultural landscapes and watersheds; new revenue
from MFA may substantially finance land-use change needed to meet TMDLs. Second, efforts to capitalize on MFA should use a
novel methodology, the Communicative/Systemic Approach (C/SA). C/SA uses an integrative GIS-based spatial modeling framework
for systematically assessing tradeoffs and synergies in design and evaluation of multifunctional agricultural landscapes,
closely linked to deliberation and design processes by which multiple stakeholders can collaboratively create appropriate
and acceptable MFA landscape designs. We anticipate that application of C/SA will strongly accelerate TMDL implementation,
by aligning the interests of multiple stakeholders whose active support is needed to change agricultural land use and thereby
meet TMDL goals. 相似文献
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