滨海盐碱地长期人工刺槐林的生长状况和叶片特性

为探讨黄河三角洲长期人工刺槐林对滨海土壤盐碱化的响应,对比了三个不同退化程度刺槐林在生长状况和叶片特性之间的差异。结果表明,土壤盐渍化的长期影响造成刺槐人工林的总体生长状况较差,保存率均在70%以下;不同退化程度人工刺槐林的胸径、树高、郁闭度等生长特征存在显著差异。退化程度严重的人工刺槐林,其叶片营养状况相对较差,叶绿素含量也较低,抗逆性能明显较弱,主要表现为叶片束缚水/自由水比值、MDA含量和脯氨酸含量增加,SOD和POD活性降低。     

Ruminal in situ disappearance kinetics of six nutritive ingredients in leaves and stems of young tetraploid black locust in growing steers

Tetraploid black locust (Robinia pseudoacacia) is a woody plant with larger leaves and richer nutritional content than normal diploid black locust, with greater biomass and wider adaptability than herbaceous plant forage. However, currently no stockbreeders have adopted it as a major forage in China and other countries for a lack of information on the evaluation of nutritional ingredients of leaves and stems of young tetraploid black locust (YTBL) by in situ digesting tests. The objectives of this study wer...     

红外和紫外照射对蝗虫卵孵化影响的研究

用红外光、紫外光照射蝗虫卵,观察其对蝗虫卵孵化率等的影响。结果表明：红外、紫外育种和杀虫具有可行性。25w的红外光照射无预先培养的虫卵20min左右可以显著提高其孵化率,迭95％以上,降低其最快孵化时间（降低4d）和加快其总体孵化速度（提前3d）。25w的紫外光照射无预先培养的虫卵40min以上,杀虫率可达87％以上,并且可以延缓其最快孵化时间（可延缓6d）。     

粉煤灰复垦区杨、柳、榆、刺槐的生物量*

粉煤灰复垦区杨、柳、榆、刺槐的生物量刘雅荣，刘建伟，王世绩，冷国友，周树理，程锦山关键词煤矿复垦区，杨，柳，榆，刺槐，生物量淮北地区煤矿开采后，形成大面积的塌陷区，造成可利用的土地面积减少，生态环境恶化。据统计，类似淮北的情况，全国以每年２万ｈｍ２的...     

马拉硫磷对东亚飞蝗不同种群遗传结构的分化研究

以接近于LD50的马拉硫磷处理东亚飞蝗Locustamigratoriamanilensis(Meyen)天津北大港和山东无棣种群个体,用SSRP-PCR标记技术分析检验东亚飞蝗在不同选择压力下,存活个体与死亡个体的基因型与马拉硫磷致死作用的可能相关关系。结果表明,无棣种群死亡组的多态性明显高于存活组,而北大港种群存活组的多态性高于死亡组,北大港群体的多态性高于无棣群体。各多态位点与马拉硫磷致死性相关性检测表明:第一,相同引物的不同位点对马拉硫磷的敏感性不同,不同种群对马拉硫磷致死性存在相关性的位点不同;第二,不同处理的东亚飞蝗在同一引物扩增出的同一位点对马拉硫磷毒性的反应不同。这些结果表明,马拉硫磷对东亚飞蝗在不同引物扩增的不同位点有选择致死作用。Nei’s遗传距离值在两个种群中都是在死亡组和存活组最高,表明马拉硫磷对东亚飞蝗种群的遗传结构产生了一定的分化作用。     

Behaviour of fipronil in soil under Sahelian Plain field conditions

The behaviour of fipronil, a phenylpyrazole insecticide used for locust control, was studied under sub-Saharan conditions in soils of the Niamey region of Niger. A formulation of fipronil (Adonis^®) was applied to uncultivated soils at Banizoumbou and Saguia. Soil was sampled at 0–10, 10–20 and 20–30 cm depths for up to two months after treatment. Residues were analysed by gas chromatography using electron capture and mass detectors. For both soils, a rapid initial decrease of fipronil was observed, with rapid formation for the most part of a photodegradate. Three other metabolites of fipronil were also detected throughout the study. These metabolites displayed different dissipation kinetics. Fipronil and its metabolites did not move beyond 10 cm depth, except for the amide, which is not considered a toxicologically significant metabolite. © 1998 SCI.     

Native oak retention as a key factor for the conservation of winter bird diversity in managed deciduous forests in northern Italy

Birds can serve as useful model organisms to investigate community level consequences of forestry practices. In this study we investigated the relationships between wintering bird communities and habitat and landscape characteristics of lowland managed forests in Northern Italy. This area is characterized by the spread of the black locust, an alien species that has been favored by forestry practices at the expense of natural oak forests. Birds were censused in winter by point counts in randomly selected plots of 50 m radius. We first addressed bird community–habitat relationships by means of habitat structure measurements, then we investigated bird community–landscape relationships by using GIS techniques. We used generalized linear models (GLM) to test for the effects of habitat and landscape variables on bird community parameters (namely bird species richness, diversity and abundance). Bird community parameters were influenced by oak biomass and tree age, and by oak area and core area, while the other forest habitat types showed less influence. In forest management terms, the main conclusion is that the retention of native oaks is the keyfactor for the conservation of winter bird diversity in local deciduous woods. At the habitat level black locust harvesting may be tolerated, provided that old, large, native oaks are retained in all local woodlots to preserve landscape connectivity and foraging resources. At the landscape meso-scale, large native oak patches, should be preserved or, where necessary, restored. Electronic supplementary material  The online version of this article (doi:) contains supplementary material, which is available to authorized users.     

崇信与毁灭:明清时期山西蝗灾的时空分布及社会应对

明清时期山西地区的蝗灾尤为突出,虽不及黄河下游的河南、山东地区严重,却也是重灾害区,且在时间和空间分布上有较强的规律性。面对蝗灾,山西地区的蝗灾防治及社会应对自成体系,存在自上而下的两条治蝗线索——直接的备灾救灾实践与间接的祈禳弭灾信仰。利益驱使下的小农会因为蝗灾的代价高昂而忽略蝗虫作为现实世界保护神的身份,对其赶尽杀绝;飞蝗蔽天难以遏制以至束手无策时,又将其高高供起。此二者虽看似逻辑矛盾(崇信还是毁灭),却在实际执行过程中并行不悖,形成明清时期山西地区乃至中国传统社会灾害防治与禳灾信仰关系处理的鲜明特色。同时,基于历史经验的治理措施,对我们今天的蝗灾防治不无启迪。     

蝗虫灾害光电诱导捕集治理研究进展及应用前景分析

灾害蝗虫的光电诱导捕集治理技术是基于蝗虫群体对光源的趋向效应,设置波谱光源与机械机构分别作为灾害蝗虫趋向行为的导向控制因素和诱集蝗虫的收集捕获因素,以此实现致灾蝗虫的有效捕集治理。蝗虫光电诱导趋向行为试验研究证实了短波谱光源的趋光诱导敏感性与趋光增效因素的控制措施,据此研制的光电诱导蝗虫滑移捕集机实现了致灾蝗虫的诱集;仿生研制的滑移捕集滑板能够有效抑制蝗虫附着系统的附着功能并促使诱集蝗虫高效滑移至捕集机的收集装置。灾害蝗虫的光电诱导滑移捕集治理能够抑制喷施化学农药防治导致的生态环境污染问题,还可实现捕获蝗虫的资源化利用,具有良好的应用前景。