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1.
岷山地区大熊猫生境评价与保护对策研究   总被引:34,自引:8,他引:26       下载免费PDF全文
综合运用大熊猫生物学与行为生态学研究成果、遥感数据分析与地理信息系统技术 ,在系统研究岷山地区大熊猫生境分布、生境质量与空间格局的基础上 ,明确岷山地区保护大熊猫的关键区域 ,分析岷山地区大熊猫保护与自然保护区建设的对策 ,以期为岷山地区大熊猫保护及其与岷山地区资源开发与发展的协调提供依据。遥感数据分析结果表明 ,岷山地区以森林为主 ,各类森林面积 1 91 790 3.4 4 hm2 ,占 5 5 .4 2 % ,将与大熊猫生境密切相关的森林植被分为常绿阔叶林、落叶阔叶林、针阔混交林、亚高山针叶林等 ,其中亚高山针叶林面积 5 380 4 9.6 4 hm2 ,占全部森林的占 2 8.0 5 % ,落叶阔叶林面积 4 6 1 35 5 .6 7hm2 ,占2 4 .0 6 % ,针阔混交林面积 4 0 30 36 .2 6 hm2 ,占 2 1 .0 1 %。结果表明岷山地区有大熊猫潜在生境 1 32 3789.1 5 hm2 ,由于森林资源利用、交通、农业活动影响、居民薪柴砍伐 ,以及生境破碎化与生境隔离等导致的生境丧失 5 5 341 3.4 5 hm2 ,目前尚存的大熊猫适宜生境 770 375 .7hm2 ,由于交通等隔离而成为至少 5个相互分隔的生境单元 ,大熊猫种群交流受到严重阻碍。为了有效地保护岷山大熊猫 ,首先应充分注意到各种人类活动 ,尤其交通的建设对大熊猫生境的影响 ;其次要扩大自然保护区范围 ,  相似文献
2.
郭继勋  祝廷成 《生态学报》1992,12(4):295-301
分解速率和损失率从不同侧面反映了枯枝落叶分解动态,羊草草原主要优势植物,羊草(Leymus chinensis),拂子茅(Calamagrostis epigejos),减蓬(Suaeda glauca),碱茅(Puccinellia tenuiflora),五脉山黎豆(Lathyrus quinqueneruivs),碱蒿(Artemisia anethifolia)分解速率的季节变化动态近似倒“V”字型,损失率的季节变化呈S型,反了枯枝落叶的失重情况,枯枝落叶的化学组成成分是造成不同种植物间分解差异的主要原因,特别是C/N比与分解快慢有密切关系,分解初期,枯枝落叶的损失符合指数衰减模型,枯枝落叶损失95%所需时间,羊草群落约为8.8a,杂类草群落约为9.7a,碱茅群落约为7.1a,碱蓬群落约为4.7a。  相似文献
3.
采用气相色谱仪和氨基酸分析仪测定中华绒螯蟹不同种群 (太湖种群和温州种群 )受精卵和温州种群流产卵脂肪酸及氨基酸的组成。结果表明 ,中华绒螯蟹太湖种群受精卵、温州种群受精卵和温州种群流产卵在必需氨基酸和半必需氨基酸的含量上无显著差异 ,而谷氨酸 (Glu)、胱氨酸 (Cys)和丝氨酸 (Ser)三种非必需氨基酸的含量差异显著。太湖种群受精卵、温州种群受精卵及温州种群流产卵的脂肪酸种类分别为 16、13和 14种。饱和脂肪酸(SFA)占脂肪酸总量的 18 96 %— 2 3 0 9% ,单烯酸 (MUFA)占 5 1 76 %— 6 2 6 5 % ,多不饱和脂肪酸 (PUFA)占14 2 7%— 2 8 96 % ,其中最主要的脂肪酸为C16∶0、C16∶1和C18∶1。除C2 0∶1外 ,其他脂肪酸含量在三者之间都有显著差异。太湖种群受精卵的C18∶2、C18∶3显著高于温州种群受精卵 ,而温州种群流产卵的DHA要显著高于太湖种群受精卵。温州种群受精卵和流产卵在C16以下的脂肪酸 ,其含量均无显著差异。此外 ,本文还讨论了脂肪酸及氨基酸含量与流产的关系及脂肪酸组成对出苗率的影响。  相似文献
4.
羊草群落水分状况的初步研究   总被引:3,自引:1,他引:2       下载免费PDF全文
 本文采用笔者自行设计和组装的人工气候箱装置,对天然羊草(Aneurolepidium chinense)群落的水分状况进行了研究,结果表明,在生长季各时期的晴天条件下,羊草群落蒸腾、蒸散速率的日进程曲线均为双峰型。群落的蒸腾、蒸散速率与太阳总辐射强度和气温呈正相关,与空气相对湿度呈负相关。群落的无效水分散失比率与蒸腾速率呈负相关。群落中植物的蒸腾强度,以开花期最高,为1.156g/cm2(叶面积)/d;整个群落的蒸腾速率在种子蜡熟期达到最高值,为4861.07g/m2(地面)/d。群落的蒸散速率在6月份最高,达6454.36 g/m2/d。群落月蒸散、蒸腾耗水量的最大值分别出现在6月份和8月份,各为125.9mm和83.9mm。在生长季中,群落的总耗水量与总降水量基本相等,但二者的季节消长不同步。在植物生长发育早期的6月份,水分亏缺严重,使群落对后期充沛的降水不能有效利用,群落生产力低下。  相似文献
5.
The polychaete worm Serpula vermicularis (Serpulidae) filterfeeds at the mouth of its calcareous tube, but retreats intothe tube when startled by mechanical stimuli likely to be associatedwith predators. While in its tube, a worm is safe but cannotfeed. Thus, hiding has a lost-opportunity cost. We show thatthis cost can be substantial, given that food in the naturalhabitat appears in pulses, and good feeding conditions may notlast long or recur frequently. We expect that a worm's hidingtime will be sensitive to the lost-opportunity cost, and wepresent data from a series of experiments that support thisprediction. The worms seem able to track relatively short-termchanges in food availability, and some evidence suggests thatthey assess food availability on a relative basis, comparingcurrent feeding conditions to those recently experienced. Hidingand other types of cryptic behavior are common antipredatortactics, and animals may commonly adjust the durations of suchbehaviors to current benefits and costs (including lost opportunity),as they perceive them  相似文献
6.
西藏米拉卡黑白仰鼻猴的栖息地变化   总被引:2,自引:0,他引:2  
黑白仰鼻猴(Rhinopithecus bieti)分布在我国金沙江和澜沧江之间的横断山脉的一个狭小区域内(26°14′N-29°20′N,99°15′E-99°37′E),海拔分布范围2600(南部)-4200m(北部);目前大约有15群,约1700只。本文所研究的西藏米拉卡猴群分布在我国西藏藏族自治区芒康县的南部,数量约50只。基于野外调查和过去的报道,此地的暗针叶林和针阔叶混交林是猴群的适宜栖息地,而由于人口数量增加所导致的夏季牧场和农田面积不断扩增正在逐渐侵蚀着这里的暗针叶林。为了评估该猴群的栖息地现状、变化趋势和变化原因,我们通过野外调查工作,利用GIS和RS技术,分别解译了当地过去5年(1986-2006年)冬季的Landsat TM卫星影像,并对解译结果进行了分析和计算,得到了该猴群栖息地的主要结果有:1)2006年暗针叶林面积是13600hmP2P,夏季牧场面积是4900hmP2P,农田面积是3300hmP2P;2)在过去20年(1986-2006年),暗针叶林面积减少了15.5%(2500hmP2P),牧场面积增加了58.1%(1800hmP2P),农田面积增加了17.8%(500hmP2P);3)暗针叶林的斑块数量增加了75.6%,平均斑块面积下降了51.8%(从1986年的15.3hmP2P到2006年的7.4hmP2P),最大斑块指数下降了54.7%;景观丰富度并没有变化,但Shannon多样性指数和Shannon均匀度指数分别增加了4.0%;4)暗针叶林面积变化与当地的人口数量呈显著负相关(r=?1.000),而夏季牧场和农田面积分别和当地人口呈显著正相关(r=1.000)。表明黑白仰鼻猴米拉卡猴群栖息地的丧失和破碎化程度较为严重;栖息地丧失和破碎化是当地传统生产方式和人口增长共同作用的结果。  相似文献
7.
通过地面调查,研究了沙漠化对科尔沁沙地农田和草地土壤有机碳和全氮含量的影响.结果表明,随着沙漠化的发展,科尔沁沙地土壤碳、氮含量明显下降.和非沙漠化农田相比,轻度、中度、重度和严重沙漠化农田土壤有机碳和全氮含量分别下降12.3%和15.3%、22.2%和24.7%、39.5%和44.7%、64.4%和63.5%;和非沙漠化草地相比,轻度、中度、重度和严重沙漠化草地土壤有机碳和全氮含量分别下降了56.3%和48.7%、78.4%和74.4%、88.9%和84.6%、91.6%和84.6%.截至2000年,科尔沁沙漠化总面积已经达到50197.5 km2,由于沙漠化而导致的土壤有机碳和全氮损失总量分别为36.39 Mt和7.89 Mt,其中草地分别占91.12%和86.06%,农田分别占8.88%和13.94%.相关分析结果表明,土壤有机碳和全氮的损失主要源于风蚀所引起的土壤粘粉粒的减少.因此,在科尔沁沙地,防治土壤风蚀对于减少农田和草地土壤碳、氮损失极为重要.  相似文献
8.
Arginine kinase plays a vital role in invertebrate homeostasis by buffering ATP concentrations. Arginine kinase might serve as a target for environmentally friendly insect-selective pesticides, because it differs notably from its counterpart in vertebrates, creatine kinase. In this study, two members of the flavonoid family, quercetin (QU) and luteolin (LU), were identified as novel noncompetitive inhibitors of locust arginine kinase. They were found to have inhibition parameters (Ki) of 11.2 and 23.9 μM, respectively. By comparing changes in the activity and intrinsic fluorescence of AK, the inhibition mechanisms of these flavonoids were found to involve binding to Trp residues in the active site. This was determined by examination of the static quenching parameter Ksv. The main binding forces between flavonoids and AK were found to be hydrophobic based on the thermodynamic parameters of changes in enthalpy (ΔH), entropy (ΔS), and free energy (ΔG) and on docking simulation results. Molecular docking analyses also suggested that flavonoids could bind to the active site of AK and were close to the Trp 221 in active site. Molecular simulation results mimic the experimental results, indicated that QU had a lower binding energy and a stronger inhibitory effect on AK than LU, suggesting that the extra hydroxyl group in QU might increase binding ability.  相似文献
9.
Integration of working environment into life cycle assessment framework   总被引:1,自引:0,他引:1  
Background, aim, and scope  Life cycle assessment (LCA) has been considered one of the tools for supporting decision-making related to the environmental aspects of a product system. It has mainly been used to evaluate the potential impacts associated with relevant inputs and outputs to/from a given product system throughout its life cycle. In most cases, LCA has not considered the impacts on the internal environment, i.e. working environment, but only the external environment. Recently, it has been recognized that the consideration of the impacts on the working environment as well as on the external environment, is needed in order to assess all aspects of the effects on human well-being. To this end, this study has developed a total environmental assessment methodology which enables one to integrate both the working environment and the external environment into the conventional LCA framework. Materials and methods  In general, the characteristics of the impacts on the external environment are different from those on the working environment. In order to properly integrate the two types into total environmental impacts, it is necessary to define identical system boundaries and select impact category indicators at the same level. In order to define the identical system boundary and reduce the uncertainties of LCI results, the hybrid IOA (input–output analysis) method, which integrates the advantages between conventional LCI method and IOA method, is introduced to collect input and output data throughout the entire life cycle of a given product. For the impact category indicators at the endpoint level, LWD (Lost Work Days) is employed to evaluate the damage to human health and safety in the working environment, while DALY (disability-adjusted life years) and PAF (Potentially Affected Fraction) are selected to evaluate the damage to human health and eco-system quality in the external environment, respectively. Results and discussion  The environmental intervention factors (EIFs) are developed not only for the data categories of resource use, air emissions, and water emissions, but also for occupational health and safety to complete a life cycle inventory table. For the development of the EIFs on occupational health and safety, in particular, the number of workers affected by i hazardous items and the number of workers affected at the i magnitude of disability are collected. For the characterization of the impact categories in the working environment, such as occupational health and safety, the exposure factors, effect factors, and damage factors are developed to calculate the LWD of each category. For normalization, the normalization reference is defined as the total LWD divided by the total number of workers. A case study is presented to illustrate the applicability of the proposed method for the integration of the working environment into the conventional LCA framework. Conclusions  This study is intended to develop a methodology which enables one to integrate the working environmental module into the conventional LCA framework. The hybrid IOA method is utilized to extend the system boundary of both the working environment module and the external environment module to the entire life cycle of a product system. In this study, characterization models and category indicators for occupational health and safety are proposed, respectively, while the methodology of Eco-indicator 99 is used for the external environment. In addition to aid further understanding on the results of this method, this study introduced and developed the category indicators such as DALY, and LWD, which can be expressed as a function of time, and introduced PAF, which can be expressed as a probability. Recommendations and perspectives  The consideration of the impacts not only on the external environment, but also on the working environment, is very important, because the best solution for the external environment may not necessarily be the best solution for the working environment. It is expected that the integration of occupational health and safety matters into the conventional LCA framework can bring many benefits to individuals, as well as industrial companies, by avoiding duplicated measures and false optimization.  相似文献
10.
西藏米拉卡黑白仰鼻猴的栖息地变化   总被引:1,自引:0,他引:1       下载免费PDF全文
黑白仰鼻猴(Rhinopithecus bieti)分布在我国金沙江和澜沧江之间的横断山脉的一个狭小区域内(26°14′N—29°20′N,99°15′E—99°37′E),海拔分布范围2 600 (南部)—4 200 m(北部);目前大约有15群,约1 700只。本文所研究的西藏米拉卡猴群分布在我国西藏藏族自治区芒康县的南部,数量约50只。基于野外调查和过去的报道,此地的暗针叶林和针阔叶混交林是猴群的适宜栖息地,而由于人口数量增加所导致的夏季牧场和农田面积不断扩增正在逐渐侵蚀着这里的暗针叶林。为了评估该猴群的栖息地现状、变化趋势和变化原因,我们通过野外调查工作,利用GIS和RS技术,分别解译了当地过去5年(1986—2006年) 冬季的Landsat TM卫星影像,并对解译结果进行了分析和计算,得到了该猴群栖息地的主要结果有:1)2006年暗针叶林面积是13 600 hm2,夏季牧场面积是4 900 hm2,农田面积是3 300 hm2;2)在过去20年(1986—2006年),暗针叶林面积减少了15.5%(2 500 hm2),牧场面积增加了58.1%(1 800 hm2),农田面积增加了17.8%(500 hm2);3)暗针叶林的斑块数量增加了75.6%,平均斑块面积下降了51.8%(从1986年的15.3 hm2到2006年的7.4 hm2),最大斑块指数下降了54.7%;景观丰富度并没有变化,但Shannon多样性指数和Shannon均匀度指数分别增加了4.0%;4)暗针叶林面积变化与当地的人口数量呈显著负相关(r=−1.000),而夏季牧场和农田面积分别和当地人口呈显著正相关(r=1.000)。表明黑白仰鼻猴米拉卡猴群栖息地的丧失和破碎化程度较为严重;栖息地丧失和破碎化是当地传统生产方式和人口增长共同作用的结果。  相似文献
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