共查询到20条相似文献,搜索用时 156 毫秒
1.
植物病原真菌是一类可开发利用的潜在资源.病原真菌对植物分泌的有害物质毒素、生长调节剂和胞外多糖均可被人类开发利用.从3个致病相关因子的角度考虑,选取具有代表性的病原菌炭疽菌(Colletotrichum sp.)、水稻恶苗病菌(Gibberella sp.)和黑粉菌(Ustilago sp.),对其可利用价值研究进行了概述. 相似文献
2.
植物种质资源是人类赖以生存的资源,是一个国家和地区重要的基础性战略物质,四川植物种质资源无论是种类还是数量在全国都居重要地位。在分析四川种质资源特点和利用现状的基础上,对积极开展四川种质资源保护利用进行了探索和研究,提出了大力开展植物种质资源及其保存和利用现状的全面调查,摸清家底,逐步建立植物种质资源保护利用数据库和网络信息平台,大力开展多种形式的示范工程建设,积极开展植物种质资源监测网络建设,加强植物种质资源的研究开发,加强植物种质资源管理运行机制建设,搭建种质资源共享平台,加强人才队伍建设等植物资源保护和可持续利用对策及其保障措施。 相似文献
3.
4.
5.
雅鲁藏布江大拐弯地区野果类资源初探 总被引:2,自引:1,他引:2
本文通过对雅鲁藏布江大拐弯地区的考察.基本摸清了该地区野生果类资源的种类及分布状况,发现了1000年树龄的野生果树.以及可供科研和开发利甲的种质资源.同时.从考古资料的研究和考察中发现西藏是多种果肉的原产地,也是天然的果树种质资源库. 相似文献
6.
四川省野生乌头资源调查研究 总被引:2,自引:0,他引:2
调查四川省野生乌头资源的分布、生态环境及蕴藏量,为四川省乌头种质资源的保护与持续利用提供科学依据.通过查阅文献和比对标本,对青川县、平武县、安县、布拖县、峨眉山市、马边县进行走访和样方调查.结果表明,四川地区野生乌头资源分布较广,北至青川县,南至布拖县,位于27°32'-32°31'N、102°17'-105°11'E,区域内低山至高山均有分布,且集中分布在海拔800-2800m的区域,但由于生态环境破坏严重,总蕴藏量仅为2975kg.建议采取措施保护野生乌头资源的生态环境,实现野生乌头资源的可持续开发利用. 相似文献
7.
野大豆的资源价值及其栽培技术 总被引:4,自引:0,他引:4
对野大豆的形态习性、资源价值以及栽培技术进行了较为详细的综述,这对保护和合理开发这一濒危野生种质资源,实现生态效益和经济效益的统一具有重要意义。 相似文献
8.
乌头种质资源形态学多态性研究初报 总被引:1,自引:0,他引:1
收集乌头种质资源,经种属鉴定,均来源于毛莨科植物乌头(Aconitum camichaeli Debx.),以南瓜叶、鹅掌叶、艾叶等3种变异类型为主。观察了全生育期间哥形态学特征,证实乌头种质资源的形态学多态性,其中南瓜叶乌头长势壮、叶面积大、叶片肥厚、茎粗、须根发达、子根数目多、形状规则、子根大,表现出良好的丰产性,可作为附子栽培的重点推广品种。这些形态学指标可直接用于3种乌头资源的早期鉴定,对附子种质资源评价和良种选育具有重要意义。 相似文献
9.
10.
1993~1994年我们考察并初步鉴定了川西南的盐边,金阳等13个县大蒜种质资源,共收集38份资源样本,表示蒜头大,品质优,但当地利用差,与我国大蒜生产区之一的成都平原上的主要栽品种相比,选出了5个优异大种质资源,建议作主国商品大蒜头和早蒜苔生产的优异品种进行开发利用。 相似文献
11.
12.
To examine whether tree rings can be used to detect or assess local historical 90Sr or 137Cs fallout, such as that resulting from the Hiroshima atomic bomb, radial distribution of 90Sr and 137Cs in trees was examined. We studied a gymnosperm [Japanese cedar, Cryptomeria japonica (L. f.) D. Don] and an angiosperm (Japanese persimmon, Diospyros kaki Thunb.) tree species from the vicinity of the atomic bomb hypocenter, and from other locations in Japan. A significant amount of 137Cs was detected in tree rings formed before 1945, indicating lateral migration of Cs. In contrast, the specific activity of 90Sr in the Hiroshima Japanese cedar showed the highest level in 1945, due to relatively immobile characteristics of Sr compared with Cs. Strontium-90 and Sr analyses in tree rings helped identify and distinguish between residual 90Sr activity from the Hiroshima atomic bomb and the atmospheric nuclear testing. This indicates the possibility of detecting or assessing previous local 90Sr pollution through with treering analysis. 相似文献
13.
A soil-active herbicide (hexazinone) was applied (0, 2, and 4 kg/ha of active ingredient) in a 3-year-old regenerating boreal Populus tremuloides Michx. (aspen) clearcut to determine its effect on the compositional and structural development of the vegetation. Woody stem densities and plant foliar cover were evaluated prior to and 2, 6, and 17 years after treatment. Herbicide treatment at the 2 and 4 kg/ha rates reduced tree and total woody stem densities relative to the 0 kg/ha level. The 4 kg/ha level reduced stem densities by 27% 17 years after treatment. The primary reductions occurred in Amelanchier alnifolia (Nutt.) Nutt. ex M. Roemer (saskatoon) and Rosa acicularis Lindl. (wild rose); whereas Corylus cornuta Marsh. (beaked hazelnut) and Viburnum edule (Michx.) Raf. (low-bush cranberry) stem densities increased. Notable herbicide-caused foliar cover reductions at the 4 kg/ha level occurred in Eurybia conspicua (Lindl.) Nesom. (showy aster), Mertensia paniculata (Ait.) G. Don. (tall mertensia), Rubus pubescens Raf. (dewberry), and Spiraea betulifolia Pallas (spiraea), but Aralia nudicaulis L. (sarsaparilla), Cornus canadensis L. (bunchberry), and Symphyotrichum ciliolatum (Lindl.) A.&D. Lve (Lindley's aster) increased. Less distinctive but similar changes occurred in the 2 kg/ha treatment. Total plant cover, species richness, and species dominance concentration were similar among treatments. Eight distinctive forest understory-types were recognized among treatments in Year 17. Between the 0 and 4 kg/ha treatments, five understory-types differed in their frequency of occurrence. Hexazinone did not improve the survival of silviculturally planted Picea glauca (Moench) Voss (white spruce) seedlings relative to untreated sites, but the 4 kg/ha treatment level did increase Pinus contorta Dougl. ex Loud. (lodgepole pine) survival from 12 to 34%. Surviving seedlings had significantly greater height and basal diameter growth than those at the 0 kg/ha sites, particularly the 4 kg/ha treatment. 相似文献
14.
The Right Tree for the Job? Perceptions of Species Suitability for the Provision of Ecosystem Services 总被引:1,自引:0,他引:1
Simeon J. Smaill Karen M. Bayne Graham W. R. Coker Thomas S. H. Paul Peter W. Clinton 《Environmental management》2014,53(4):783-799
Stakeholders in plantation forestry are increasingly aware of the importance of the ecosystem services and non-market values associated with forests. In New Zealand, there is significant interest in establishing species other than Pinus radiata D. Don (the dominant plantation species) in the belief that alternative species are better suited to deliver these services. Significant risk is associated with this position as there is little objective data to support these views. To identify which species were likely to be planted to deliver ecosystem services, a survey was distributed to examine stakeholder perceptions. Stakeholders were asked which of 15 tree attributes contributed to the provision of five ecosystem services (amenity value, bioenergy production, carbon capture, the diversity of native habitat, and erosion control/water quality) and to identify which of 22 candidate tree species possessed those attributes. These data were combined to identify the species perceived most suitable for the delivery of each ecosystem service. Sequoia sempervirens (D.Don) Endl. closely matched the stakeholder derived ideotypes associated with all five ecosystem services. Comparisons to data from growth, physiological and ecological studies demonstrated that many of the opinions held by stakeholders were inaccurate, leading to erroneous assumptions regarding the suitability of most candidate species. Stakeholder perceptions substantially influence tree species selection, and plantations established on the basis of inaccurate opinions are unlikely to deliver the desired outcomes. Attitudinal surveys associated with engagement campaigns are essential to improve stakeholder knowledge, advancing the development of fit-for-purpose forest management that provides the required ecosystem services. 相似文献
15.
Nishimura S Maie N Baba M Sudo T Sugiura T Shima E 《Journal of environmental quality》2012,41(3):823-833
Chromophoric dissolved organic matter (CDOM) leached from leaf litter is a major source of humus in mineral soil of forest ecosystems. While their functions and refractoriness depend on the physicochemical structure, there is little information on the quality of CDOM, especially for that leached in the very early stages of litter decomposition when a large amount of dissolved organic matter (DOM) is leached. This study aimed to better understand the variations/changes in the composition of CDOM leached from senescent leaf litter from two tree species during the early stage of decomposition. Leaf litter from a conifer tree (Japanese cedar, D. Don) and a deciduous broad-leaved tree (Konara oak, Thunb.) were incubated in columns using simulated rainfall events periodically for a total of 300 d at 20°C. The quality of CDOM was investigated based on the fluorescence properties by using a combination of excitation-emission matrix fluorescence (EEM) and parallel factor analysis (PARAFAC). In addition, the phenolic composition of DOM was investigated at a molecular level by thermally assisted hydrolysis and methylation-gas chromatography-mass spectrometry (THM-GC-MS) in the presence of tetramethylammonium hydroxide (TMAH). The EEM was statistically decomposed into eight fluorescence components (two tannin/peptide-like peaks, one protein-like peak, and five humic-like peaks). A significant contribution of tannin/peptide-like peaks was observed at the beginning of incubation, but these peaks decreased quickly and humic-like peaks increased within 1 mo of incubation. The composition of humic-like peaks was different between tree species and changed over the incubation period. Since tannin-derived phenolic compounds were detected in the DOM collected after 254 d of incubation on THM-GC-MS, it was suggested that tannins partially changed its structure, forming various humic-like peaks during the early decomposition. 相似文献
16.
17.
18.
19.
María L. Pignata Martha S. Cañas Hebe A. Carreras Liliana Orellana 《Environmental management》1997,21(5):793-801
Ligustrum lucidum Ait. f. tricolor (Rehd.) Rehd. in relation to atmospheric pollutants in Córdoba city, Argentina. The study area receives
regional pollutants and was categorized taking into account traffic level, industrial density, type of industry, location
of the sample point in relation to the street corner, treeless condition, and topographic level. Dried weight/fresh weight
ratio (DW/FW) and specific leaf area (SLA) were calculated, and concentrations of chlorophylls, carotenoids, total sulfur,
soluble proteins, malondialdehyde (MDA), and hydroperoxy conjugated dienes (HPCD) were determined in leaf samples. Sulfur
content correlates positively with traffic density and SLA correlates negatively with some combinations of the categorical
variables; MDA correlates positively with topographic level and total protein concentration correlates negatively with treeless
condition. On the basis of our results, traffic, location of trees, type of industry, situation of a tree with respect to
others, and topographic level are the environmental variables to bear in mind when selecting analogous sampling points in
a passive monitoring program. An approximation to predict tree injury may be obtained by measuring DW/FW ratio, proteins,
pigments, HPCD, and MDA as they are responsible for the major variability of data. 相似文献
20.
/ Investigation of a delta marsh restoration project proposed forthe Don River in Toronto, Ontario, underlines several concerns aboutconstructed wetland projects designed for water quality improvement andaquatic habitat enhancement. The Don is a highly urbanized river that hasundergone significant physiographic modifications and continually receives acomplex mixture of conventional, metallic, and organic contaminants frommultiple point and nonpoint sources. Rather than providing permanent removalof urban contaminants, wetland processes offer a limited capacity fortemporary storage of contaminant inputs, and potential reactions may actuallyproduce more toxic and/or bioavailable forms of some chemicals. Theseprocesses tend to result in the concentration of watershed contaminants inwetland vegetation and sediments. As the restored marsh would be availablefor spawning and feeding by aquatic fauna, the potential exists for chemicalbioconcentration and biomagnification through the aquatic community.Accordingly, wetland systems are not suited to the dual purposes of waterquality improvement and aquatic habitat enhancement. Upstream controls,including source reduction of contaminant inputs, are recommended asessential components of all constructed wetland projects.KEY WORDS: Constructed wetlands; Water quality; Ecological restoration;Don River 相似文献