城市绿化树木栽植与管理方式的几点反思——对2003年冬北京大雪造成"树灾"的调查

2003年11月6日北京大雪对城市绿化树木造成了罕见的伤害。本文在对树木受灾情况进行调查的基础上,综合分析了树木受灾的主要因素,探讨了目前树木栽植、管理方式等与树木受灾的关系,并提出了改进建议。     

江西省主要产煤区煤矸石堆特性研究

矿山废弃地植被生态重建的主要障碍是废弃地不良的土壤环境,而煤矸石堆该方面问题尤为突出。笔者以煤矸石堆置地为研究对象,分别选取江西10个主要产煤区煤矸石,测定其理化性质、重金属含量。研究结果为江西煤矿废弃地煤矸石堆置地土壤改良和植被恢复提供理论指导。     

Combination of serum phosphorylated neurofilament heavy subunit and hyperintensity of intramedullary T2W on magnetic resonance imaging provides better prognostic value of canine thoracolumbar intervertebral disc herniation

The aim of this study was to evaluate the prognostic value of concurrent measurement of serum phosphorylated neurofilament heavy subunit (pNF-H) concentration and intramedullary T2W hyperintensity in paraplegic to paraplegic dogs. Our hypothesis was that concurrent measurement of these would provide a more accurate prediction of functional outcome in dogs with thoracolumbar intervertebral disc herniation (IVDH). A prospective case-control clinical study was designed using 94 dogs with acute onset of thoracolumbar IVDH. The association of serum pNF-H concentration, T2W hyperintensity on sagittal MRI (T2H/L2), deep pain perception and surgical outcome were evaluated with logistic regression analysis after three months for all 94 surgically treated dogs. Sensitivity to predict non-ambulatory outcome was compared among pNF-H and T2H/L2 and combination of both. Logistic regression analysis indicated that serum pNF-H concentration and T2H/L2 were significantly correlated with surgical outcome (P<0.05); however, deep pain perception was not (P=0.41). The results of logistic regression analysis indicated that the odds ratios of unsuccessful long-term outcome were 2.6 for serum pNF-H concentration, 1.9 for T2H/L2 and 2.3 for deep pain sensation. The sensitivity and specificity to predict non-ambulatory outcome for using serum parameter pNF-H>2.6 ng/ml, using T2H/L2 value of>0.84 and using both serum pNF-H and T2H/L2, were 95% and 75.7%, 65% and 86.5%, and 90.0% and 97.5%, respectively. Therefore, combined measurements of serum pNF-H and T2H/L2 might be useful for predicting long-term outcome in dogs with thoracolumbar IVDH.     

湖北铜绿山铜矿区土壤铜污染状况及优势植物对铜的吸收

矿区重金属污染十分严重,寻找并筛选适合当地生长的优势植物成为推广矿区植物修复技术的前提。铜绿山矿区土壤重金属铜含量高,在矿区发现4种优势植物。通过测定植物根际土壤及植物各器官铜含量,得出在此4种植物对铜的积累与迁移特点,评估其在矿区土地恢复与植被重建方面的作用与价值。     

镉对苗期高羊茅的形态和生理影响

以20份高羊茅(Festuca arundinacea)品种为试验材料,通过测量其形态指标,运用标准差系数赋予权重法,对其进行综合评价。结果筛选出耐镉性较强的高羊茅材料M15和M8,分别采自美国的猎狗5和荷兰的巴弗斯;耐镉性较差的高羊茅材料M5和M11,分别采自荷兰的米斯特拉尔和来自日本的法恩。在此基础上,采用分光光度法,测定了这4份材料的生理指标,过氧化物酶(POD)、过氧化氢酶(CAT)、叶绿素和脯氨酸(Pro)含量的变化,进一步研究了他们的生理反应。结果表明,随着镉浓度的升高,耐镉性较强的高羊茅材料猎狗5与和巴弗斯POD和CAT含量一直呈上升趋势,而耐镉性较差的材料米斯特拉尔和法恩POD和CAT含量则呈现先升后降的趋势。随着镉浓度的升高,不同材料的叶绿素含量呈下降趋势,不同材料的脯氨酸含量则呈不断上升趋势。     

A preliminary trial of the sedation induced by intranasal administration of midazolam alone or in combination with dexmedetomidine and reversal by atipamezole for a short‐term immobilization in pigeons

ObjectiveTo assess the sedative and immobilization effect of intranasal administration (INS) of midazolam (MID) without or with INS dexmedetomidine (DXM), and some physiological changes induced by the drugs. The ability of INS atipamezole to reverse the DXM component was also assessed.Study designProspective ‘blinded’ experimental study.AnimalsIn total, 15 pigeons.MethodsPigeons were sedated by INS MID alone at a dose of 5 mg kg⁻¹ (group MID, n = 6) or in combination with INS DXM at a dose 80 μg kg⁻¹ (group MID-DXM, n = 6). Measurements were made of heart rate (HR), respiratory rate (f_R) and cloacal temperature (CT). The degree of sedation was assessed at 15 minutes prior to, immediately after, and at intervals until 100 minutes after drug administrations. Following MID-DXM, INS atipamezole (250 μg kg⁻¹) was administered and the same indices measured 5 and 10 minutes later.ResultsMID had no effect on HR and f_R, and although CT decreased, it remained within physiological range. MID-DXM caused significant falls in HR, f_R and CT that persisted until the end of sedation. Atipamezole antagonized sedation and cardiorespiratory side effects of MID-DXM within 10 minutes of application. In addition, for MID compared to MID-DXM, the lowest sedation scores [10 (7–14) and 10.5 (5–14) versus 2 (1–4) and 2 (1–5)] were achieved in the 10th and 20th minute versus the 20th and 30th minute of the sedation, respectively.Conclusions and clinical relevanceMID alone, given INS had minimal side effects on vital functions but caused inadequate immobilization of pigeons for restraint in dorsal recumbency. MID-DXM caused an effective degree of immobilization from 20 to 30 minutes after administration, at which time birds tolerated postural changes without resistance. Atipamezole antagonized both side effects and sedation, but complete recovery had not occurred within 10 minutes after its application.     

Accelerated induction of etorphine immobilization in blue wildebeest (Connochaetes taurinus) through the addition of hyaluronidase

ObjectiveTo study the effects of the addition of hyaluronidase (HA) to an etorphine/azaperone drug combination on induction times of immobilization.Study designExperimental part-randomized ‘blinded’ cross-over study.AnimalsEight wild managed blue wildebeest (Connochaetes taurinus).MethodsAnimals were immobilized, on separate occasions separated by two weeks, with one of four treatments. Treatments were; ‘Control drugs (CD), etorphine 0.01 mg kg⁻¹ + azaperone at 0.1 mg kg⁻¹; treatment 1 CD + 5000IU HA; treatment 2 CD + 7500 IU HA; and treatment 3 etorphine 0.007 mg kg⁻¹ + azaperone at 0.07 mg kg⁻¹ + 7500 IU HA. Times to first effect and to immobilization (from darting to possible to approach and blindfold) were measured. anova was used to compare treatments. Results are given in means ± SD (range).ResultsFor control, and treatments 1–3 respectively, times (in minutes) to first effect were 1.58 ± 0.42 (1.02–2.10), 1.64 ± 0.42 (0.95–2.17), 1.12 ± 0.24 (0.80–1.48) and 1.60 ± 0.21 (1.13–1.88) and to immobilization were 5.38 ± 1.53 (3.82–8.07), 3.80 ± 1.14 (2.02–5.50), 3.51 ± 1.08 (2.28–5.52) and 4.46 ± 0.67 (3.30–5.40). Compared to control, time to first effect for treatment 2 was significantly shorter. Time to immobilization was significantly quicker in all three treatments containing HA than that for control.Conclusion and clinical relevanceHyaluronidase can reduce the time to immobilization when used in the immobilizing dart, and might be usefully incorporated into etorphine combinations for darting wildlife.     

上海宝山区城市表土重金属累积的空间分布规律

检测了上海宝山区127个表土样点的重金属含量。宝山区表土Zn、Cr、Cd、Pb、Cu、Ni、Mn的平均含量分别为228.6、127.6、0.56、118.5、55.2、55.7、718.7mg/kg。其中Pb、Zn、Cd的含量分别是上海土壤背景值的5.6、3.0、2.8倍,受污染较明显。宝山区地表的重金属含量呈现出明显的空间分布规律:工业区地表,如吴淞、大场等地,多种重金属污染均很重,Zn、Cr、Cd、Pb、Cu的平均含量分别高达407.6、319.0、0.75、101.2、76.2mg/kg;马路绿地土壤Pb的累积较显著,平均为180.2mg/kg;远郊菜地土壤重金属污染不明显。     

海南西部热带雨林次生林土壤易氧化有机碳分布特征及影响因素

【目的】检测云南八角主产区林地土壤重金属污染水平,为八角产地土壤环境质量评价、潜在 风险评估提供参考依据。【方法】以云南省文山州 7 个县的八角林地土壤为研究对象,测定土壤重金属 As、 Cd、Cu、Cr、Pb、Hg、Zn 和 Ni 的含量,应用单项和综合污染指数对林地土壤重金属污染风险进行评价。 【结果】检测区土壤重金属变异系数在 7.11%~18.75% 之间,Hg、As、Pb、Cr 的平均含量超过云南省土壤重金 属背景值,As、Pb、Cu 超过风险筛选值。污染评价表明,As 单因子污染指数平均值最高为 1.99,为警戒级别, 内梅罗综合污染指数评价为轻污染;潜在生态风险因子和潜在生态风险指数均处于低风险等级,其中 Cd 生态风 险因子最高;地质累积指数 Hg 和 As 在 1~2 之间,为中度污染等级。聚类分析表明,林地土壤重金属 As、Pb、 Cd、Cu、Zn、Hg 主要受土壤母质和人类活动的共同影响,Cr 和 Ni 来源相似,主要为自然来源。【结论】云南 八角种植区土壤重金属含量差异较大,受人类活动和成土母质的共同影响,部分区域重金属存在一定程度的超 标现象。     

基于微波消解-原子吸收光谱法进行土壤重金属检测方法的研究

[目的]选择微波消解来进行土壤样品前处理,原子吸收光谱法测定重金属元素,以期提高土壤重金属检测效率。[方法]对三种标准土样进行检测,并对农田土壤样品进行三个水平的添加回收试验。[结果]结果表明,微波消解-原子吸收光谱法测定土壤铜、锌、锰、镍、铬以及镉时,标准土样的回收率为94%-107.69%,农田土壤添加回收率为87.08%-104.34%。[结论]该方法可以用作土壤重金属检测。