Decomposition in five woodland soils: relationships with some invertebrate populations and with weather

Summary In two alluvial forests, a beech forest, an oakhazel-wood and a spruce forest, correlations between abiotic factors and the different groups of soil animals on the one hand and the decomposition rate (mean rate of disappearance) on the other hand have been the subject of investigation. There is a positive correlation between Lumbricidae and Brachycera imagines and the pH and the decomposition rate, but a negative one with Enchytraeidae and Nematocera imagines.Varying weather conditions are of great importance for decomposition processes. The influence of temperature seems to be insignificant. In the deciduous forests fluctuations of precipitation correlate fairly well with fluctuations in rates of decomposition, because of the high abundance of lumbricids. The spruce forest has very few lumbricids and the influence of weather on the course of decomposition is insignificant. Yet there is only a very loose relationship with the annual fluctuations of weather conditions. Only a major event such as the relatively low temperature and precipitation of 1980 is capable of inhibiting the development of sciarid larvae and enchytraeids and hence reducing the ensuing decomposition rate in 1981 and possibly even in 1982. The reason for this is that sciarid larvae and imagines, for example, go through critical periods during their development, which are influenced by the weather, frequently with a time lag of 1 year.Long-term investigations in the spruce forest have established a high correlation between sciarid larvae and enchytraeids and the decomposition rate.Dedicated to the late Prof.Dr. M.S. Ghilarov     

苜蓿蓟马的研究

本文报道了我国苜蓿蓟马的种类、蓟马危害的症状、因蓟马危害造成苜蓿干草产量损失达20.1%。各种营养成分也有大幅度下降。并报道了优势种牛角花齿蓟马的生活史与发生规律。通过农药的筛选试验、筛选出1∶500—1∶1000倍的40%乐果乳剂是防治苜蓿蓟马的有效农药,并强调了抗虫育种工作应作为今后防治苜蓿蓟马的主要方法。     

杭州非栽培植物上访花蓟马种类调查及发生分析

为明确蓟马在野外不同植被上的发生动态,了解不同蓟马的寄主偏好性。从4月中旬至11月中旬,每2周对杭州茅家埠多种植物花上的蓟马种类进行采集并在室内进行种类鉴定,并且对几种主要植物的几种蓟马种群动态进行分析,包括对金丝桃Hypericum chinese花上的花蓟马Frankliniella intonsa、西花蓟马F.occidentalis、黄胸蓟马Thrips hawaiiensis及黄蓟马T.flavus;一年篷Erigeron annuus花上的花蓟马、西花蓟马、小头蓟马Microcephalothrips sp;空心莲子草Alternanthera philoxeroides花上的花蓟马、西花蓟马及黄胸蓟马及美人蕉Canna indica花上的花蓟马、黄胸蓟马、黄蓟马及茶黄硬蓟马Scirtothrips dorsalis发生进行分析。调查发现蓟马种类分属6属16种,其中花蓟马、黄胸蓟马及黄蓟马是该地主要的蓟马种类。分析发现,金丝桃上花蓟马是优势种,其他几种只是偶尔发生,一年篷上优势种是小头蓟马并且发生量在开花的后期较多,即在整个7月,空心莲子草上蓟马的数量在开花的早期较多,从6月初至7月初,后期减少明显,主要是花蓟马和西花蓟马两种,美人蕉上主要的蓟马种类是黄蓟马和黄胸蓟马,在整个开花期,有3个发生高峰期,分别为7月上中旬,9月中下旬及11月上中旬,并且种群发生量大,最高时达到每花101.60±13.89头。同时花蓟马的数量也较高,最高时每花达12.60±4.35头,因此从上述的分析发现,花蓟马的适宜寄主范围广,除一年篷花上较少外,其他3种植物的花上都较多,这3种植物都可作为花蓟马的虫源地,黄蓟马和黄胸蓟马的主要适宜寄主为美人蕉花,西花蓟马则在空心莲子草上发生较多,而小头蓟马的适宜寄主则是一年篷。     

青蛤不同地理群体遗传结构差异的AFLP分析

[目的]探讨青蛤种群遗传多样性水平和遗传分化特征。[方法]采用AFLP技术对我国山东潍坊(WF)、江苏南通(NT)、浙江宁波(NB)、浙江温州(WZ)沿海共4个青蛤地理群体的遗传结构差异进行了分析。[结果]5对引物共得到261个位点,4个群体的多态位点比例平均为82.95%,其中WZ群体最高(86.97%),NT群体最低(78.93%);4个群体Nei’s基因多样性指数分别为0.258 1、0.252 6、0.271 3和0.277 6,香农多样性指数分别为0.394 7、0.383 0、0.412 0和0.421 4;群体遗传变异主要来自于群体内,占96.39%;WF和NT群体、NB和WZ群体遗传关系较近,聚类分析分别先聚在一起。[结论]研究的青蛤4个群体遗传基础较好,且尚未有明显的遗传分化。     

基于SSR标记的山西省辽东栎自然居群遗传多样性分析

利用SSR分子标记对山西省8个辽东栎天然群体进行遗传多样性分析,并与北京东灵山小龙门林场群体进行地理距离和遗传距离相关关系的对比分析,旨在为辽东栎遗传多样性保护提供一定的依据。研究使用11对SSR引物进行遗传多样性分析,得到平均等位基因数为10.272 7,平均有效等位基因数为5.185 9;得出山西省辽东栎群体的平均期望杂合度为0.753 8,Nei多样性指数为0.752 1,Shannon多样性指数为1.754 3。这一结果表明辽东栎的遗传多样性水平是相对较高的。研究还表明,辽东栎群体的绝大部分遗传变异是发生在群体内的（95.99%）,仅有4.01%的遗传变异发生在群体间,并且遗传距离和地理距离之间具有显著的正相关关系（r=0.752 2,P0.05）。      

陕西黄河湿地鸟类资源调查分析与研究

陕西黄河湿地是我国中、西部国际候鸟的主要栖息地之一和内陆候鸟迁徙通道上的重要驿站,区内生境多样,鸟类资源十分丰富。通过对湿地内高生芦苇区、低矮芦苇区、盐碱地、农田、鱼塘、莲池、滩涂、林地等不同生境类型的鸟类分布情况进行的调查分析,结果共记录到16目39科132种,较2005年增加了3科13种,为陕西黄河湿地鸟类资源保护提供了科学依据。     

Behavioural response of a trophic specialist, the Iberian lynx, to supplementary food: Patterns of food use and implications for conservation

Prey scarcity compromises population survival, especially for specialist predators. Supplementary feeding is a management tool that can be applied to reverse the decline of food-limited populations. We analyse how a population of Iberian lynx, a threatened food specialist, initially reacted to, and subsequently used, supplementary food. Twenty-seven feeding stations (FS) with domestic rabbits were placed in the Doñana Biological Reserve, SW Spain, between 2002 and 2005. We recorded lynx tracks inside and around stations to analyse spatio-temporal patterns of use, as well as the performance of several station designs. Iberian lynx used 62% of the FS installed, and consumed most of the supplied food. All station designs were used and food provision apparently covered the energetic needs of the lynx inhabiting the reserve. There was spatial aggregation in the use of the FS. Fourteen weeks were needed on average for lynx to become familiar with feeding stations and making a regular use of the supplementary food. Seasonal variations in consumption frequency appeared to be modulated by fluctuations of wild rabbit numbers throughout its annual cycle as well as by variation in energy demand of breeding females. The Iberian lynx responded positively to our supplementary feeding programme. We show that this technique allows the persistence of lynx populations during long periods in areas where wild rabbits are extremely scarce. Supplementary food may be used to sustain lynx whenever rabbit populations need recovery, as well as in the context of lynx restocking or reintroduction programmes.     

Temporal and spatial distribution of an invasive thrips species Scirtothrips dorsalis (Thysanoptera: Thripidae)

Dispersion of a new invasive thrips species in the United States, chilli thrips Scirtothrips dorsalis Hood, was studied on three plant hosts, i.e., cotton (Gossypium hirsutum L.), peanut (Arachis hypogeal L.) and pepper (Capsicum annum L.) in the greenhouse and under field conditions in Homestead, Florida. In the vertical distribution study, a strong negative relationship was observed between thrips density and height, with the significantly highest mean number of larvae and adults reported on host plants placed at the lowest height (45.7 cm) above ground. The study of horizontal distribution showed that S. dorsalis has weak dispersal potential and aggregates in open areas. During the entire six week study period, thrips were found to move a maximum of 12 m from their reservoir population. During two years (2009–2010 and 2010–2011) of study, a high abundance of thrips population was observed during May–October with the highest mean count during July and August in both years. Flight activity of adults was highest between 10:00and16:00 EST, during peak solar radiation (∼337–653 w/m²). Results from these studies will help growers and extension personnel predict farm-scale distribution of S. dorsalis and efficiently monitor the pest for management before they become a serious problem for the vegetable and ornamental industry in the United States.