抚顺西排土场矸石山阴坡物种多样性变化特征     

张咏新  赵思金 《林业科技》2012,37(5):55-58

抚顺西排土场矸石山阴坡随着排矸年限的增加，物种多样性发生变化，物种数由初期的4科5种增至后期14科29种。植被由最初的鹅绒藤＋豚草＋刺蒺藜群落，逐步演变到榆树群落。在阴坡，不同排矸年限的样地，植物群落多样性指数随着排矸时间的延长而增加；物种综合多样性指数、丰富度指数与排矸年限呈显著正相关关系。  相似文献   

苔藓植物生态学研究的数量分析方法   总被引：5，自引：0，他引：5  

张元明  郭水良  曹同  潘伯荣 《干旱区研究》2001,18(1):69-72,75

植被数量分析方法在苔藓植被中的应用起步较晚，仅有20多年的研究历史，但发展却十分迅速。这里介绍了目前苔藓植物生态学研究中应用较为普遍的数量分析方法，并探讨了各自的优缺点。  相似文献   

新疆哈纳斯自然保护区地衣群落的聚类分析   总被引：3，自引：0，他引：3  

阿不都拉阿巴斯  艾尼瓦尔·吐米尔  帕提古丽·马合木提  努尔巴衣·阿不都沙勒克 《干旱区研究》2001,18(3):25-28

我们根据多年的实地调查结果并采用聚类分析方法对分布在哈纳斯国家级自然保护区的地衣群落进行了研究。结果表明分布在该地区的地衣种类有 10 3种 ,他们分别属于 2 0科 ,4 0属。地衣物种形成了 6种群落。同时发现该地区地衣对基物形成专一性 ,它们的基物包括 :树皮、藓丛、藓土、草地、石面、地面、土层、石浮土等。  相似文献   

勒克瑙根结线虫居群对我国亚热带丝瓜的危害     

唐本安  唐敏  石亮明 《植物保护》2001,27(5):7-9

通过田间对感根结虫病的丝瓜植株取样调查发现 ,勒克瑙根结线虫居群对中国亚热带地区丝瓜生产危害较大 ,受害面积占调查面积的30% ,减产25%以上。研究发现勒克瑙根结线虫居群危害丝瓜的原因是丝瓜属于勒克瑙根结线虫的寄生植物 ;防治勒克瑙根结线虫居群危害最有效、最经济的方法是利用勒克瑙根结线虫属专性植物寄生线虫的生物学特性 ,实行蔬菜品种轮作。  相似文献   

Community Forestry and Sustainable Development in Rural Area     

XU GuozhenCollege of Resources  Environment Central South Forestry University. Zhuzhau . P.R. China 《中国林业科技(英文版)》2003,(4)

After analysis on the current situation of international forestry, this paper proposes that integration, coordination and sustainable development will be the general developing trend of forest in China, and commercial forest, ecological forest and community forest should be organically combined with integrative development and sustainable development in rural areas. This paper focuses especially on clarifying the importance of community forest to the social development or rural areas, and emphasizes that the key point of forestry should be turned from biological and technical aspects to humane and social aspects.  相似文献   

熏蒸直接提取法测定土壤MB－S中几个因素的研究     

胡正义  张继榛  张贤应 《安徽农业科学》1996,(1)

就影响薰蒸直接提取法测定土壤ＭＢ－Ｓ的一些因素（预培养时间和土壤湿度，氯仿消杀时间，浸提剂与土壤比例和振荡时间）进行了研究，提出了适用于一般实验室测定土壤ＭＢ－Ｓ的较好程序。  相似文献   

河西走廊绿洲外围沙化草地固沙造林效果研究   总被引：1，自引：0，他引：1  

李福  韩天虎  豆卫  喻文虎  向金城  刘克彪  陈鸿 《草原与草坪》2006,(5):30-33

通过对流动沙丘固沙造林效果的对比研究,结果发现:未固沙造林的沙丘,丘间低地是以芦苇和赖草为优势种的原生群落,沙丘迎风坡植被稀疏,不形成植物群落,而实施固沙造林技术20年后的沙丘,虽丘间低地群落组成成分变化不大,但流动沙丘被完全固定,中下部形成以引入固沙灌木柠条锦鸡儿、花棒为优势种的人工植物群落,植物种类增加,生产力提高,草地生态系统得到有效恢复。固沙造林沙丘与未固沙造林沙丘相比,丘间低地群落高度增加51.6%,产草量增加12.6%,盖度增加4.7%,多度无变化,密度提高15%,物种丰富度指数提高25%,均匀度指数提高34.8%;迎风坡下部群落高度增加87.1%,产草量增加13%,多度提高一个等级,密度增加15%,物种丰富度指数提高228%,均匀度指数提高22.8%;迎风坡中部群落高度增加453.7%,产草量增加64.5%,多度提高一个等级,密度增加128.9%,物种丰富度指数提高616%,均匀度指数提高33.3%;迎风坡上部植被非常稀疏,不形成群落,植株平均高度25.3 cm,产草量增加206.8%,多度提高一个等级,密度增加550%,物种丰富度指数提高800%,均匀度指数提高66.7%。  相似文献   

Fermented liquid feed and fermented grain to piglets- effect on gastrointestinal ecology and growth performance   总被引：1，自引：0，他引：1  

N. Canibe  B.B. Jensen 《Livestock Science》2007,108(1-3):198-201

A study was carried out to determine the microbial and nutritional characteristics of dry feed, liquid feed containing fermented liquid cereal grain, and fermented liquid compound feed, and their effect on gastrointestinal ecology and growth performance of piglets. Three dietary treatments were designed: dry feed (DRY); fermented liquid cereal grain feed (FLG); and fermented liquid feed (FLF). The FLF was prepared by removing three times daily 50% of the mixture (feed and water) stored in a tank at 20 °C and replacing it with an equal amount of fresh feed and water. The FLG was similarly prepared but fermenting only the cereals (barley and wheat) and adding the remaining ingredients immediately before feeding. One hundred and twenty weaners were fed the diets during 6 weeks from weaning. The dietary content of lysine (g/100 g protein) was 6.01 in the DRY diet, 6.21 in the FLG diet, and 5.46 in the FLF diet. Feeding piglets with the FLG diet resulted in a higher density of yeasts, a higher concentration of ethanol in the GIT, and a change of the bacterial population of the stomach compared to feeding FLF. The FLG group had a numerically higher daily feed intake and daily body weight gain compared to the FLF group, but the values were not significant. Feeding liquid feed containing fermented liquid cereal grains as a means of avoiding microbial degradation of free amino acids in the feed and increasing feed intake by improving palatability seems promising.  相似文献   

黄河上游重大生态功能区草地逆型演替植物多样性变化研究   总被引：2，自引：0，他引：2  

陈文业  郑华平  戚登臣  李广宇  刘振恒 《中国草地学报》2007,29(6):6-11

基于5个样地、90个样方的野外调查资料,研究了玛曲县不同退化程度草地群落植物多样性和地上生物量变化情况。结果表明：多样性指数与丰富度指数、均匀度指数及地上生物量有显著线性关系,而与优势度指数呈显著负相关。原生地带性群落以及演替早期类群多样性、均匀度、盖度及地上总生物量最高,在极度退化阶段,地上总生物量最低,优势度指数最大,随着退化程度加剧,草地群落的盖度、物种多样性指数、均匀度指数均下降,毒杂草、莎草增多,禾草急剧下降,最终导致草地初级生产力的降低。  相似文献   

Effects of different types of dietary non-digestible carbohydrates on the physico-chemical properties and microbiota of proximal colon digesta of growing pigs     

M. Roca-Canudas  M. Anguita  M. Nofrarías  N. Maj  A.M. Prez de Rozas  S.M. Martín-Orúe  J.F. Prez  J. Pujols  J. Segals  I. Badiola 《Livestock Science》2007,109(1-3):85-88

The effect of different types of fibre on the intestinal digesta and microbial diversity was evaluated in growing pigs. The animals were fed during forty-two days with one of four experimental diets including a control group, a diet enriched with resistant starch type I, by coarse ground corn, and other two diets containing sugar beet pulp (8%) and wheat bran (10%) (as sources of soluble and insoluble non-starch polysaccharides respectively). Body weight (BW) and average daily feed intake (ADFI) were assessed at day 7, 21 and 42. Luminal samples of digesta from proximal colon were collected to analyse water retention capacity (WRC), concentration of short-chain fatty acids (SCFA) and the microbial diversity. Overall, animals fed with higher amounts of non-digestible carbohydrates had lower ADFI and BW. Sugar beet pulp provoked an increase of WRC, a higher concentration of SCFA, and a more stable microbial diversity throughout the experimental period. On the other hand, animals fed with wheat bran presented a lower bacterial diversity.  相似文献