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391.
Burkhard O. Wagner 《Umweltwissenschaften und Schadstoff-Forschung》1998,10(4):245-253
Zusammenfassung UNEP International Register of Potentially Toxic Chemicals (IRPTC) wurde von der ersten VN-Umweltkonferenz 1972 geschaffen.
Sein Einfu? und Zusammenwirken in den 80ziger Jahren mit anderen internationalen Programmen der WHO, FAO, OECD und EG in der
Chemikalienkontrolle wird beschrieben. Nach dem Erdgipfel von Rio 1992 werden im VN-Rahmen drei neue Gremien gebildet, die
das Fachprogramm des Kapitels 19 der Agenda 21 (umweltfreundliches Chemikalienmanagement) umsetzen sollen: die United nations
Commission of Sustainable Development, das Intergovernmental Forum on Chemical Safety und das Interorganization Programme
for the Sound Management of Chemicals. Der Erdgipfel brachte auch für IRPTC eine Neuorientierung. Seit 1996 hat UNEP Chemicals,
wie sich IRPTC nunmehr nennt, drei Aufgaben in sein Arbeitsprogramm aufgenommen, die beschrieben werden: das internationale
übereinkommen zum Prior Informed Consent, das internationale übereinkommen zur Kontrolle der Persistent Organic Pollutants,
und schlie?lich sein traditionelles Arbeitsgebiet des Informations-austausches über Stoffe wird weitergeführt.
Die Aussagen dieses Beitrages sind die Meinung des Autors. Sie müssen nicht mit der Auffassung des Umweitbundesamtes oder von UNEP Chemicals übereinstimmen. 相似文献
Die Aussagen dieses Beitrages sind die Meinung des Autors. Sie müssen nicht mit der Auffassung des Umweitbundesamtes oder von UNEP Chemicals übereinstimmen. 相似文献
392.
化工制药工艺残渣燃烧过程固氯研究 总被引:1,自引:0,他引:1
采用管式固定床反应器对化工制药工艺残渣的燃烧分解进行了实验研究,进一步通过加入氧化钙/碳酸钙来防止燃烧过程残渣中氯的释放.实验结果表明,残渣在燃烧时氯主要以氯化氢形式排出,加入固氯剂后能有效地抑制氯化氢的生成,且固氯效果随着钙化物投加量的增加而明显提高.当氧化钙/残渣比(质量比)达到0.8时,固氯率可达97%以上;当碳酸钙/残渣比(质量比)提高到2.0时,固氯率为76%.与此对应的Ca/Cl摩尔比分别为30和40.继续增加钙投加量,固氯效果基本不变.同时发现添加一定量的木屑在助燃的同时有助于提高固氯效果. 相似文献
393.
The timing of chemical signaling with urine in dominance fights of male lobsters (Homarus americanus) 总被引:2,自引:0,他引:2
Chemicals carried in the urine are a rich source of information about the identity, sex, aggressive motivation, and other
attributes of an animal. In agonistic interactions, animals should be careful about disclosing such information, since it
can be used by receivers to the disadvantage of the sender. By adjusting the timing of urine release, the signaler may still
influence the behavior of the receiver to its own benefit. Here we investigate the urine signaling of American lobsters (Homarus americanus), necessary for the maintenance of dominance, using a catheter technique with high temporal resolution. We hypothesize that
urine release in lobster fights is not continuous but restricted to moments that may elicit a reaction in the receiver beneficial
to the sender. We found that eventual winners signaled more readily in the initial phase of the fight. Eventual losers did
not show such initial urination. This suggests that a confident lobster may use urine signals to influence the behavior of
its opponent into giving up the fight at an early stage. For both winners and losers, urine release is linked to offensive
behavior and increases as the intensity of agonistic behavior increases. The coupling of urine release to offensive behaviors
appears to improve both the reliability and efficacy of the chemical signal. Releasing urine under the increasing risk of
inflicting injury during the fight provides a handicap that may ensure reliability of the threat signal. Furthermore, the
immediate coupling of urine components to offensive behavior may help to consolidate the receiver"s memory of the signaler"s
individual scent and thus facilitate future recognition of the dominant animal.
Received: 6 October 1999 / Accepted 28 August 2000 相似文献
394.
395.
蔬菜地土壤磷提取及模拟径流中磷素潜在流失的影响 总被引:1,自引:1,他引:1
蔬菜地磷素流失是一种典型农业非点源污染类型。通过观测地表径流中溶解态反应磷(DRP)、生物可利用磷(BAP)可以监测土壤磷素流失程度。受到各种客观条件的限制,这两个指标比较难于获取,而土壤中的总磷(TP)、Olsen(OP)、Mehlich-1(M-1P)和水溶性磷(Pw)可以通过常规分析手段获取。本文选取27个典型蔬菜样地,分析测定各样地土壤中的总磷(TP)、Olsen(OP)、Mehlich-1(M-1P)和水溶性磷(Pw)四个磷提取变量,采用了经典方法计算土壤磷流失潜能指标——磷吸持饱和度(DPS)。同时采用模拟径流实验得出典型蔬菜样地地表径流样中溶解态反应磷(DRP)、生物可利用磷(BAP)。结果表明:M-1P、Pw与DPS呈极显著正相关,相关系数分别达到了0.85和0.74(p<0.01);而M-1P、Pw与DRP浓度相关系数(r2=0.843和0.786,p<0.01)大于TP、OP与DRP浓度的相关系数(r2=0.554和0.722,p<0.01)。结论认为,通过测定M-1P、Pw和计算DPS能比较准确、便捷地预测土壤径流磷素流失风险程度。 相似文献
396.
卜兆宏 《生态与农村环境学报》1994,(4)
本研究利用太湖区代表站30年和43个一般站25年的降雨资料,改进和完善了降雨侵蚀力新算法,使之与经典法达到90%的一致性,查清了该区降雨侵蚀力时空变化持证,并编制出全区阵雨侵蚀力(R)值分布图。同时,还时R值在水土保持、耕作制度变革和防洪减灾中的应用,尤其对1991年特大洪涝灾害的根本原因,作了讨论。太湖区R值较大,不可忽视水土保持,做好山区、坡耕地的水土保持,是防洪减灾最长久有效的根本措施。 相似文献
397.
Polona Kalan Katarina Košmelj Charles Taillie Anton Cedilnik John H. Carson 《Environmental and Ecological Statistics》2003,10(4):469-482
The objective of this paper is to quantify and compare the loss functions of the standard two-stage design and its composite sample alternative in the context of multivariate soil sampling. The loss function is defined (conceptually) as the ratio of cost over information and measures design inefficiency. The efficiency of the design is the reciprocal of the loss function. The focus of this paper is twofold: (a) we define a measure of multivariate information using the Kullback–Leibler distance, and (b) we derive the variance-covariance structure for two soil sampling designs: a standard two-stage design and its composite sample counterpart. Randomness in the mass of soil samples is taken into account in both designs. A pilot study in Slovenia is used to demonstrate the calculations of the loss function and to compare the efficiency of the two designs. The results show that the composite sample design is more efficient than the two-stage design. The efficiency ratio is 1.3 for pH, 2.0 for C, 2.1 for N, and 2.5 for CEC. The multivariate efficiency ratio is 2.3. These ratios primarily reflect cost ratios; influence of the information is small. 相似文献
398.
Brian?D.?WisendenEmail author Mike?S.?Pollock Robyn?J.?Tremaine Jeff?M.?Webb Monique?E.?Wismer Douglas?P.?Chivers 《Behavioral ecology and sociobiology》2003,54(5):485-490
Chemical and visual sources of information are used by aquatic prey during risk assessment. Here, we test the behavioral response of littoral prey fish to combinations of chemical alarm cues (skin extract) and the visual presence of a fish shoal. We scented minnow traps with either alarm cues or water (control) placed inside the trap, a jar that contained either a fish shoal or nothing (control), and recorded the number and species of fish captured. We predicted that chemical alarm cues would reduce the number of fish captured and that a fish shoal would increase the number of fish captured. The predicted effect of chemical and visual cues combined depended on the nature of the interaction. We found that the lowest catch rate was for the combination of alarm cue + no shoal, but the highest catch rate occurred for the combination of alarm cue + shoal. Fish shoal + water had the second highest catch rate and no shoal + water had the second lowest catch rate. We conclude that chemical alarm cues induce area avoidance in the absence of a shoal, but a strong behavioral proclivity to increase shoal cohesion in the presence of a shoal. The presence of a shoal in the traps induced alarmed fish to shoal with them and thus, enter the traps. This occurred even though traps were the source of the alarm cue.Communicated by A. Mathis 相似文献
399.
Summary. Many secondary plant compounds are involved in defense against both insect herbivores and pathogens. Two secondary plant
compounds of Plantago lanceolata, the iridoid glycosides catalpol and its precursor aucubin, are well known for their deterrent effects on generalist and
non-adapted specialist insect herbivores. We tested the effects of these compounds on the in-vitro growth of a specialist
and generalist fungal pathogen of this host species. Two chemical forms of these iridoids were tested. The glycosides and
their aglycones, the products of enzymatic conversion by specific $/Beta$-glucosidase enzymes. The glycosides enhanced growth
of both the specialist fungus Diaporthe adunca and the generalist fungus Fusarium moniliforme var. subglutinans. The positive effect of these glycosides on the generalist fungus is in sharp contrast with the generally negative effects
of these glysosides on generalist insect herbivores. The aglycones of aucubin and catalpol reduced the growth of the specialist
fungus D. adunca, but, contrary to expectation, enhanced the growth of the generalist fungus F. moniliforme var. subglutinans. Effects of aucubin on D. adunca were stronger than effects of catalpol. This was true both for the growth stimulating effects of the glycosides and for the
fungitoxic effects of the aglycones. We therefore expect that the effects of these iridoids in P. lanceolata on the specialist fungus will strongly depend on the ratio between catalpol and its precursor aucubin and the chemical form
(glycoside or aglycone) in which these compounds are encountered by the fungus during growth. Our results suggest that iridoid
glycosides in P. lanceolata can be used as defense against both herbivores and pathogens, but that their effects are highly specific with respect to
the natural enemy species that is encountered.
Received 11 April 2002; accepted 9 August 2002 相似文献
400.
酸雨对农业生产的影响及其对策 总被引:5,自引:0,他引:5
酸雨是严重的环境问题之一。我国南部地区已成为继欧洲、北美之后世界第三大酸雨区。酸雨对农业生态环境和农作物产量产生严重的影响,并带来巨大的经济损失。控制酸雨的危害.主要控制各种来源的SO2排放。文章根据农业可持续发展的战略思想,提出各种有效的防治对策。 相似文献