土壤石油污染对2种藜科植物种子发芽率的影响

[目的]筛选土壤石油类污染敏感指示指标、确定石油类污染土壤生物修复植物。[方法]在实验室人工控制条件下,研究不同浓度土壤石油污染对2种藜科植物种子萌发的影响。[结果]土壤石油污染质量分数为500 mg/kg时,对2种藜科植物种子的出芽都有一定的促进作用,对翅碱蓬的促进作用大于碱蓬,土壤石油污染浓度在1 000~30 000 mg/kg时,皆抑制2种种子的出芽,对翅碱蓬的抑制小于碱蓬。[结论]在土壤污染情况下种子萌发率具有某种程度的不确定性,土壤石油污染对2种藜科植物种子萌发的抑制率指标只能作为生态评价的初级指标或土壤开始发生污染的信号,而不宜作为深度评价的标准。     

生长调节剂对青冈根坨苗生长的影响

[目的]加速青冈的繁殖进程。[方法]研究不同生长调节剂对促进青冈根坨苗生长的影响。[结果]与对照相比,GA 50~100 mg/L+CaCl21~20 mg/L和GA 50 mg/L+NAA 20 mg/L提高发芽率7.0%~13.5%,提高发芽势14.3%~18.0%;青冈播种苗主根发达,侧根较少。该试验采用50穴格穴盘对其进行容器育苗,在苗龄30 d左右时,用浓度为20 mg/L NAA浇灌幼苗根部,促使侧根生长。结果表明,与对照相比,侧根数提高38.8%,生理质量较优,叶绿素含量提高68.9%,叶、枝、根含水率分别提高33.7%、15.9%、7.0%,根的导电率下降55.7%。[结论]青冈种子按常规处理发芽时间较长,且发芽不整齐;生长调节剂GA、NAA对青冈根坨苗生长有促进作用。     

淡竹实生苗构件生物量模型拟合与分配

淡竹(Phyllostachys glauca)是中国优良的中型经济和绿化竹种,具有显著的经济效益和生态效益。为揭示淡竹幼苗的生长发育规律,测量了淡竹1年生实生苗的多个形态学指标,采用Logistic模型和多项式函数对其生物量进行数学模型拟合,分析了多个构件在不同发育阶段的生物量变化、生物量因子之间的相互关系及生物量分配。结果表明:淡竹1年生实生苗多个构件生长量随时间的关系服从Logistic模型,株高与干质量之间线性相关显著,地上和地下生物量分配在不同生长时期具有明显差异。本研究揭示了淡竹1年生实生苗的生长发育规律,不仅为中型经济竹种的快速培育和集中经营提供理论依据,对其商业化的生产开发也具有较大参考价值。     

赤皮青冈光合作用的日变化研究

[目的]研究濒危珍稀树种赤皮青冈光合作用的日变化规律。[方法]使用开放式气体交换LI-6400便携式光合测定系统对赤皮青冈的光合速率、蒸腾速率、气孔导度和胞间CO2浓度等光合生理指标进行了测定。[结果]赤皮青冈的净光合速率日变化曲线呈双峰型,赤皮青冈蒸腾速率和气孔导度的日变化呈现单峰曲线,赤皮青冈胞间CO2浓度的日变化...     

华木莲在赣北的适应性初报

通过对濒危物种华木莲10 a的物候、生长观测及繁殖研究,得出该物种适合在赣北生长的结论,并提出合理开发利用的建议。     

广西饲草养牛奶肉役力成绩回顾及展望

本文论述喂饲草、秸秆或其他残渣时黄牛、水牛的奶肉役力成绩。作者认为，本生产方式是发展广西养牛的一条有效途径，并介绍了适合广西环境条件栽培的国外优良牧草，如象草、银合欢等的特性及饲草价值。     

粗枝木麻黄接种弗兰克氏菌的研究

试验结果表明：粗枝木麻黄接种弗兰克氏菌对提高其生长量效果显著。接种不同弗兰克氏菌菌株的粗枝木麻黄苗木的生物量。根瘤重量和数量及叶片Ｎ含量均表现出明显的差异，其中以８８０５２、８７０６６和８７２８７菌株接种效果最好。在接菌与施肥的试验中，接菌不施肥处理的苗木叶片Ｎ含量最高。     

Pathology associated with retained fishing hooks in blue sharks, Prionace glauca (L.), with implications for their conservation

Fishing hooks retained from previous capture events were found in 6 of 211 blue sharks, Prionace glauca (L.), landed in the summers of 1999 and 2000 by recreational fishermen off Long Island (New York, USA). The hooks were embedded within the distal oesophagus ( n =3), or perforated the gastric wall ( n =3) and lacerated the liver ( n =2). The hooks were surrounded by excessive fibronecrotic tissue which ablated the normal anatomical structures and in the three sharks with oesophageal hooks caused partial luminal obstruction. Accompanying lesions included oesophagitis, gastritis, hepatitis and proliferative peritonitis. Aeromonas sp. and Vibrio sp. were isolated from the peritoneal fluid of one shark with peritonitis and intralesional bacteria were seen on histological examination in all sharks. This is the first report of the prevalence and pathology of retained fishing hooks in a large number of wild-caught sharks.     

福建青冈林恢复过程中植物物种多样性的变化

对福建黄楮林自然保护区的福建青冈Cyclobalanopsis chungii林5个不同恢复阶段的群落采用时空互代的方法,研究其恢复过程中植物物种多样性的变化.结果表明,福建青冈林恢复过程中乔木层、灌木层的物种更替较剧烈;阳性树种在群落中的地位较弱;随恢复期增长,物种α多样性指数增大,群落的稳定性也增大,且群落间的共有种数增多.福建青冈林的恢复各阶段是朝着稳定性增强的方向演替的,提高其物种多样性有利于其恢复和重建.表5参11     

Family Variation in the Morphology and Physiology of White Spruce (Picea glauca) Seedlings in Response to Elevated CO2 and Temperature

Tree improvement programs aim to develop families that are well-adapted to future growing conditions. To gain insight into the stability of the family genetic response to climate change, white spruce (Picea glauca) seedlings from 60 full-sib families were subjected to a combination of two temperature regimes and two levels of CO₂ over two growing seasons. There was positive effect of warmer temperatures and higher CO₂ on some growth variables but no significant family × treatment interactions. Instantaneous water use efficiency was the only physiological trait that was affected positively by the CO₂ treatment, showing a 51% increase that was consistent across families.