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1.
为了摸清大亮子河具有开发利用价值的野生浆果资源的种类、分布、用途及蕴藏量,我们于2005—2007年6—9月,通过线路调查、样地调查和访问调查的方法,对该地区野生浆果资源进行了研究。结果表明该地区有开发利用价值的野生浆果资源达20种,隶属19属14科。并对该地区野生浆果资源的产业化开发利用潜力和优势进行了深入分析,认为该地区野生浆果资源开发利用具有广阔的市场前景,最后提出开发利用过程中需要注意的问题。因此,本研究可为今后大亮子河野生浆果资源的可持续开发利用和合理保护提供科学依据。  相似文献   

2.
本文论述了山西珍稀野生花卉种质资源的种类、观赏特性和应用前景,并进一步分析了其生态特点和开发利用途径,为今后山西珍稀野生花卉的研究和开发利用提参考.  相似文献   

3.
中国葛属植物资源和利用情况   总被引:3,自引:0,他引:3  
介绍中国葛属植物的种、开发利用情况、葛根的营养成分、化学成分及其在医药、保健食品、保持水土、饲料、纺织和造纸等工业开发利用,并对葛属植物资源的今后发展提出建议。  相似文献   

4.
在对土著鱼类资源状况分析的基础上,进一步阐释了土著鱼类资源保护和开发利用对于水生生态保护、渔业结构调整、渔民收入增加和人们膳食结构改善具有重要的意义,总结了云南土著鱼类资源保护和开发中取得成绩和存在的突出问题,从制度建设、栖息地保护、投入机制、技术支撑和产业化等方面提出了对土著鱼类资源保护与开发利用所应采取的对策建议,为云南土著鱼类资源保护与开发利用提供借鉴。  相似文献   

5.
本文介绍了黑龙江省东部林区山梨野生资源开发利用中存在的问题,野生山梨资源经营与保护、人工栽培技术、利用价值,提出了山梨资源开发利用的对策,为开发利用本省这一宝贵资源提供依据.  相似文献   

6.
广东省川山群岛开发利用生态风险评价   总被引:6,自引:3,他引:3  
李晓敏  张杰  曹金芳  马毅 《生态学报》2015,35(7):2265-2276
随着海洋经济的迅猛发展,海岛的开发利用程度不断加大,海岛生态环境遭到极大地冲击和破坏,导致海岛生态系统出现环境恶化、灾害加剧的趋势。广东省川山群岛,主岛为上川岛和下川岛,因岛上旅游娱乐和养殖用海等开发利用活动频繁,使其生态系统面临严峻的挑战。根据EPA提出的生态风险评价框架,分析了川山群岛的生态终点、生境类型和压力源状况,构建了一个用以描述川山群岛压力源、生境和评估终点间相互关系的概念模型,采用RRM模型思想进行了川山群岛开发利用风险评价。结果表明:上川岛属于开发利用的高风险区,主要风险区域是潮间带和近海两个生态子系统,其中以岩滩的开发利用压力最大,旅游娱乐和养殖用海是风险压力的主要来源,珍稀水禽是主要受威胁的物种;下川岛较上川岛的开发利用风险低,其岛陆、潮间带和近海3个生态子系统的开发利用压力都不大,养殖用海、旅游娱乐和城镇用地是风险压力的主要来源,也是威胁珍稀水禽和猛禽的主要压力源。基于此,从旅游管理、养殖用海管理等方面给出了上川岛和下川岛的风险管理对策,以期为海岛环境保护和可持续利用提供科学依据。  相似文献   

7.
广西紫金牛属野生观赏植物的综合评价   总被引:3,自引:0,他引:3  
利用层次分析法,综合观赏价值、资源开发潜力、生物学特性三大约束因素共14个指标,对分布于广西的29种紫金牛属野生观赏植物进行综合评价。结果表明:按照开发利用价值的高低,可将29个种(变种)根据轻重缓急划分为4个等级,其中:Ⅰ级:开发利用价值高的种类,5个;Ⅱ级:开发利用价值较高的种类,9个;Ⅲ级:开发利用价值一般的种类,9个;Ⅳ级:开发利用价值较低的种类,6个。研究结果将为科学、合理地开发利用广西紫金牛属野生观赏植物资源提供决策依据。  相似文献   

8.
藤本植物开发利用价值的综合评价   总被引:1,自引:0,他引:1  
根据藤本植物的生态生物学特性及其在城市园林绿化中的应用,确定了评价藤本植物开发利用价值的目标层,包括株型、叶型及叶色、攀附能力、抗逆性、资源数量、利用程度等16个标准层指标的层次分析(AHP)评价模型.应用这一模型对中国科学院华南植物园引种栽培的81种藤本植物进行开发利用价值的综合评价.结果表明,首冠藤、蔓生金虎尾、锦屏藤、山蒟、异叶爬山虎等8种藤本植物有很高的开发利用价值,心叶蔓绿绒、东南爬山虎、砾叶粉藤、粉叶羊蹄甲等24种藤本植物有较高的开发利用价值,假蒟、樟叶木防已等19种藤本植物开发利用价值低.该评价模型及分析结果将为合理开发利用藤本植物资源提供理论依据.  相似文献   

9.
虎舌红野生资源的开发利用   总被引:10,自引:1,他引:9  
论述虎舌红的主要生物学特征、资源分布、园林用途及保健药效,并提出开发利用的策略,展望其开发利用的前景.  相似文献   

10.
基于景观格局的海岛开发潜在生态风险评价   总被引:10,自引:0,他引:10  
王常颖    张杰    辛红梅  付军 《生态学报》2008,28(6):2811-2811~2817
海岛生态系统是一种相对独立的生态系统,与岛外的信息交流比较少,甚至是没有,一旦对海岛造成损害是很难恢复的,因此,对海岛进行风险评价是海岛保护和管理的重要依据.海岛风险评价通常有两个方面,海岛自然灾害风险评价和海岛开发利用风险评价.针对海岛开发利用风险评价,应用遥感手段分析了海岛景观格局与海岛开发利用风险程度的关系,定义了海岛开发利用威胁指数和强度指数,建立了基于景观格局的海岛开发利用风险评价模型.然后,以2005年4月5日获取的5m分辨率的SPOT遥感影像为数据源,将提出的模型应用到渤海海域庙岛群岛中的大黑山岛、小黑山岛、北长山岛、南长山岛和庙岛进行评价,由现场调查情况分析可知评价结果是合理的.与传统的风险评价模型相比,本模型的优势在于应用遥感影像作为数据源,大大降低了对实地调查数据的需求.  相似文献   

11.
Seeds contain the embryo as a new plant in miniature and have two major functions, reproduction and dispersal. Seed formation completes the process of plant reproduction and, with seed germination, the next plant generation starts. Given the ever-increasing environmental pollution with metal(loid)s, it is perhaps surprising that relatively few reports detail the impacts of metals on seed metabolism, viability and germination in comparison to the numerous publications on the effects of metals in vegetative tissues, particularly roots and shoots. This review provides information on metal(loid) homeostasis, detoxification and tolerance in relation to seed metabolism and performance. The delivery of metals from the mother plant into seeds and their implications on seed development are discussed, as are their uptake upon seed imbibition and subsequent effects on seed germination. Implications for seeds and seedlings on the biochemical and molecular level are discussed and finally, applied aspects are considered regarding the use of seeds for soil and water purification, and in phytoremediation programmes. We conclude with a perspective on future metal research in relation to seed biology.  相似文献   

12.
Effective breast cancer management and decreasing breast cancer fatalities is contingent upon reliable diagnostic procedures and treatment modalities, including those based on ionizing radiation. On the one hand, ionizing radiation is widely used for cancer diagnostics and therapy, on the other hand it is genotoxic cancer-causing agent. Here we discuss recent studies on the effects of low (diagnostic) and high (treatment) doses of ionizing radiation on healthy breast cells, breast cancer cells, and cancer cells resistant to common drug therapies.  相似文献   

13.
The Phytophagous Insects Data Base (PIDB) was used to summarize information about 6933 species of British insects/mites and their food-plant families. Total species in 183 insect families on 127 vascular plant families were correlated with numbers of plant species in each family in Britain and Europe, accounting for 41.8% of the variation. Families with trees had more insects, while ferns and aquatic, uncommon and ephemeral plants, particularly orchids, had fewer. Seven individual insect families were analysed separately: Aphididae were more closely correlated with plant species numbers than were the more polyphagous Geometridae. Agromyzidae were uncommon on families with trees. Of insect species 75.8% fed on only one plant family and 10.1% were recorded on two families. Species feeding on three families or more were considered to be polyphagous. In the 30 largest insect families, eight had species feeding on only one plant family, while 12 had more than 20% of their species polyphagous. Proportions of family-restricted insects were high on Pinaceae, Gramineae and Compositae, but low on Corylaceae, Primulaceae and Tiliaceae. More pest species were polyphagous. Polyphagy was related to large larvae, larvae overwintering, wood-feeding, ephemeral food sources, poor dispersal abilities and omnivory. Some polyphagous species might be actively evolving in exploitation of vacant niches, leading to later progressive specialization to food-plants.  相似文献   

14.
本文对两种载脂蛋白B的相对分子质量及其氨基酸残基数进行了详细的考证,指出国内外常见的生物化学或分子生物学教材/参考书在这些方面的若干疏误,初步分析了个中缘由,并就教材的编写和使用提出一些建议。  相似文献   

15.
Aim Conservation of species is an ongoing concern. Location Worldwide. Methods We examined historical extinction rates for birds and mammals and contrasted island and continental extinctions. Australia was included as an island because of its isolation. Results Only six continental birds and three continental mammals were recorded in standard databases as going extinct since 1500 compared to 123 bird species and 58 mammal species on islands. Of the extinctions, 95% were on islands. On a per unit area basis, the extinction rate on islands was 177 times higher for mammals and 187 times higher for birds than on continents. The continental mammal extinction rate was between 0.89 and 7.4 times the background rate, whereas the island mammal extinction rate was between 82 and 702 times background. The continental bird extinction rate was between 0.69 and 5.9 times the background rate, whereas for islands it was between 98 and 844 times the background rate. Undocumented prehistoric extinctions, particularly on islands, amplify these trends. Island extinction rates are much higher than continental rates largely because of introductions of alien predators (including man) and diseases. Main conclusions Our analysis suggests that conservation strategies for birds and mammals on continents should not be based on island extinction rates and that on islands the key factor to enhance conservation is to alleviate pressures from uncontrolled hunting and predation.  相似文献   

16.
Natural and intercalated Wyoming montmorillonite (MMT) with the tetramethylammonium (TMA) cations were used for the adsorption of phenol and aniline. Laboratory experiments characterised by adsorption isotherms were compared with the results of molecular modelling simulations. Aniline adsorbed itself strongly on MMT; while using the TMA intercalates (TMA-MMT), its adsorption decreased. On the contrary, the adsorption of phenol on TMA-MMT was moderately higher than on the MMT surface. The MMT surface models were described by empirical force field used in molecular mechanics and dynamics. The Burchart–Universal force field was used in the Cerius2 modelling environment. The modelling results revealed the important role of water forming a moderately concentrated layer on the pure MMT surface. Water molecules enable the adsorption of aniline on MMT and, on the contrary, repel phenol molecules from MMT. In the case of TMA-MMT, lower amount of water near a silicate layer caused decrease in the aniline adsorption and, on the contrary, increase in the phenol adsorption.  相似文献   

17.
Relative to the West Indies, the ecology and evolution of anoles inhabiting islands off Central and South America have received little attention. The paucity of studies on continental islands has limited our ability to generalize and extend results based on the West Indian paradigm, as well as our understanding of the profound differences between the adaptive radiations of continental vs. Greater Antillean anoles. Here we compare the morphological, ecological, behavioural and genetic divergence between Anolis nebulosus populations inhabiting a small island in the Bay of Chamela, Mexico, and a nearby mainland forest. Notably, the two populations exhibit intra‐sexual dimorphism with respect to head and limb sizes, the first such polymorphism documented for an Anolis species. We also compare the shape of island and mainland A. nebulosus with each other, the six West Indian ecomorphs and a hypothetical generalist species. Finally, we address the generalist convergence hypothesis for anoles on single species islands. We conclude that convergence on a generalist morphology is widespread among solitary anoles in the West Indies. We present data on a limited sample of solitary anoles with mainland ancestors that suggest a parallel convergence on a similar generalist morphology, probably due to similar adaptive landscapes shaped by selective forces common to small island environments.  相似文献   

18.
The interactions of adenine and thymine with and adsorption on zeolites were studied using different techniques. There were two main findings. First, as shown by X-ray diffractometry, thymine increased the decomposition of the zeolites (Y, ZSM-5) while adenine prevented it. Second, zeolite Y adsorbed almost the same amount of adenine and thymine, thus both nucleic acid bases could be protected from hydrolysis and UV radiation and could be available for molecular evolution. The X-ray diffractometry and SEM showed that artificial seawater almost dissolved zeolite A. The adsorption of adenine on ZSM-5 zeolite was higher than that of thymine (Student-Newman-Keuls test-SNK p<0.05). Adenine was also more greatly adsorbed on ZSM-5 zeolite, when compared to other zeolites (SNK p<0.05). However the adsorption of thymine on different zeolites was not statistically different (SNK p>0.05). The adsorption of adenine and thymine on zeolites did not depend on pore size or Si/Al ratio and it was not explained only by electrostatic forces; rather van der Waals interactions should also be considered.  相似文献   

19.
Protection from inappropriate or hazardous exposure to ultrasound is controlled through international standards and national regulations. IEC standard 60601 part 1 establishes requirements for the mechanical, electrical, chemical and thermal safety for all electro-medical equipment. The associated part 2 standard for diagnostic medical ultrasonic equipment sets no upper limits on ultrasonic exposure. Instead, safety indices are defined that are intended to advise users on the degree of thermal and mechanical hazard. At present the display of these safety indices satisfies regulatory requirements in both the USA and Europe. Nevertheless there are reservations about the effectiveness of this approach to protection management. In the USA, there are national regulatory limits on diagnostic exposure, based on acoustic output from clinical equipment in use over 20 years ago. The IEC 60601 part 2 standard for therapeutic equipment sets 3 W cm−2 as the limit on acoustic intensity. Transducer surface temperature is controlled for both diagnostic and therapy devices.

For airborne ultrasound, interim guidelines on limits of human exposure published by the IRPA are now 2 decades old. A limit on sound pressure level of 100 dB for the general population is recommended. The absence of protection standards for infrasound relates to difficulties in measurement at these low frequencies.  相似文献   


20.
虫草素的研究开发现状与思考   总被引:5,自引:1,他引:5  
杨涛  董彩虹 《菌物学报》2011,30(2):180-190
虫草素是第一个从真菌中分离出来的核苷类抗菌素,具有抑菌、抗肿瘤、抗炎等非常广谱的生物学活性,目前已经成为一个研究热点。对虫草素的菌株来源、生物合成、提取纯化、分子生物学研究现状等方面进行了总结,对有关专利进行了评价和分析,提出从种质资源入手拓宽虫草素来源,优化虫草素的提取纯化方法,深入研究其生物合成途径,并呼吁重视真菌研究中所用材料的科学名称。  相似文献   

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