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61.
随着农作物种质资源数量的不断增加,种质资源交流的日益频繁以及种质资源利用的逐步深入,农作物种质资源数据库的建设对农作物的应用研究和基础性研究至关重要。上海市农业生物基因中心借助于本中心保存的近21万份种质资源的信息,开发了一套上海农作物种质资源数据库,本文主要阐述了该数据库设计和构建的目的、原则和数据库的架构、运行环境以及主要功能模块。上海农作物种质资源数据库采用了B/S结构,平台系统利用多层逻辑架构实现了对农作物种质资源数据信息的收集、存储、查询、统计分析等功能。外部用户通过浏览器即可访问平台系统,浏览查询种质资源信息。内部管理员可使用平台的受限功能,需要认证成功后才可使用后台管理功能,实现对整个平台数据的管理。注册用户还可通过基因资源数据库提交引种申请,管理员结合管理信息系统实现对外供种全流程的网络化,借此可提高工作效率,增加工作流程的透明度。  相似文献   
62.
烟梗是烟草工业的重要副产物,也是宝贵的自然资源。本研究首先利用白腐菌漆酶对烟梗丝进行预处理,提升了添加烟梗丝的卷烟品质;然后分别以木质素、纤维素、半纤维素和果胶的降解率为响应值,采用Box-Behnken设计建立方程模型,对漆酶、纤维素酶、半纤维素酶和果胶酶组成的复合酶预处理烟梗丝条件进行了优化。结果表明:每100g烟梗丝加入30U漆酶,在料液比为35%、温度为30℃、酶解pH为5处理48h的条件下预处理的烟梗丝对提升卷烟品吸效果最佳,烟梗丝中木质素、纤维素、半纤维素和果胶的降解率分别为20.16%、15.10%、7.20%和12.40%;为获得与之相同的各组分降解率,响应面法优化漆酶复合酶最佳处理条件为:每100g烟梗丝加入漆酶14.72U、纤维素酶1.00U、半纤维素酶1.00U、果胶酶8.45U。验证发现烟梗丝各组分降解率实测值与理论值无显著性差异,且显微结构观察显示复合酶处理后的烟梗丝表面致密结构被破坏,孔洞数量明显增加。本研究获得的白腐菌漆酶预处理后的烟梗丝在卷烟中的添加能有效改善卷烟品质,且漆酶复合酶的使用大幅减少了漆酶的用量,降低了漆酶预处理烟梗丝的成本,为废弃烟梗生物质的资源化利用提供了重要依据。  相似文献   
63.
黑水虻作为近年来广受关注的资源昆虫,其规模化应用的基础理论研究成为热点。本文对其胚胎发育过程进行研究,利用显微镜对资源昆虫黑水虻卵孵化发育过程进行观察并拍照,对胚胎各个时期的发育时间和形态进行记录。试验发现,在32℃下,黑水虻卵的发育历期为51 h。黑水虻的胚胎发育经过卵裂期、胚盘胚带形成期、原肠形成期、胚体分节期、体壁形成期、器官形成期6个典型时期。试验对孵化过程中的15个具体发育时期的特征和发育时间进行记录,形成了一套虫卵镜检技术应用于实际生产。在生产上,通过镜检技术对每一批次待孵化虫卵进行镜检观察,可初步判定该批次待孵化虫卵所处的发育阶段和死亡率,预估虫卵孵化时间和孵化率,为规模化稳定培育黑水虻苗种提供理论依据。  相似文献   
64.
Where data and information are lacking, structured expert risk assessments can provide a powerful tool to progress natural resource planning. In many situations, practitioners make informal assessments of risk within small groups that typically constitute employees. In this study, we report on three small (in terms of experts) structured expert‐based risk assessment case studies conducted by expert employees of a not‐for‐profit organisation (Australian Wildlife Conservancy) to demonstrate the utility of the approach. The case studies were carried out for three wildlife sanctuaries managed by AWC: Faure Island, Karakamia and Paruna. The likelihood that a set of direct risk factors would cause management failure for sets of important wildlife elements in the three sanctuaries was elicited from the small group of ecological experts. The analysis was couched in terms of a management aim to not lose species from each wildlife element over the management period of 25 years with current management. The experts believed, in particular, that increasing temperature and decreasing water availability associated with climate change were likely to impact significantly upon the vegetation elements and water‐reliant fauna associated with the sanctuaries. Some vegetation elements were also thought likely to be at risk of over‐grazing, unsuitable fire regimes and, in some cases, disease. In addition to predation by exotic predators at one sanctuary, the experts identified additional direct risk factors for various fauna elements associated with expected changes to the vegetation elements, including reduction in food availability, nesting habitat, and generally important life media. From the risk analyses, a preliminary conceptual model was developed to underpin monitoring and to indicate areas for possible management intervention and research. The case studies demonstrate that even in a small workplace team, structured risk assessments can be efficiently accomplished and can provide expedient and transparent information that effectively captures and aggregates the views of the experts.  相似文献   
65.
66.
Land‐use changes and the expansion of protected areas (PAs) have amplified the interaction between protected and unprotected areas worldwide. In this context, ‘interface processes' (human–nature and cross‐boundary interactions inside and around PAs) have become central to issues around the conservation of biodiversity and ecosystem services. This scientific literature review aimed to explore current knowledge and research gaps on interface processes regarding terrestrial PAs. At first, 3,515 references related to the topic were extracted through a standardized search on the Web of Science and analyzed with scientometric techniques. Next, a full‐text analysis was conducted on a sample of 240 research papers. A keyword analysis revealed a wide diversity of research topics, from ‘pure' ecology to sociopolitical research. We found a bias in the geographical distribution of research, with half the papers focusing on eight countries. Additionally, we found that the spatial extent of cross‐boundary interactions was rarely assessed, preventing any clear delimitation of PA interactive zones. In the 240 research papers we scanned, we identified 403 processes that were studied. The ecological effects of PAs were well documented and appeared to be positive overall. In contrast, the effects of PAs on local communities were understudied and, according to the literature focusing on these, were very variable according to local contexts. Our findings highlight key research advances on interface processes, especially regarding the ecological outcomes of PAs, the influence of human activities on biodiversity, and PA governance issues. In contrast, main knowledge gaps concern the spatial extent of interactive zones, as well as the interactions between local people and conservation actions and how to promote synergies between them. While the review was limited to terrestrial PAs, its findings allow us to propose research priorities for tackling environmental and socioeconomic challenges in the face of a rapidly changing world.  相似文献   
67.
姜孟楠  魏强 《生物资源》2020,42(3):322-326
本文从微生物物种的多样性保护以及病原微生物资源的保藏等方面详细阐述了微生物资源保护与保藏的相互关系与重要性,介绍了微生物多样性保护及其研究进展和意义,病原微生物保藏的概述、资源的收集与共享,以及保藏机构相关信息。  相似文献   
68.
The availability of sufficient and diverse resources across time is important for maintenance of biodiversity and ecosystem functioning. In this study, we examine the potential for variation in environmental conditions across topographic gradients to extend floral resource timing. Flowering time on a landscape may vary across topography due to differences in abiotic factors, species turnover, or genotypic differences. However, the extent to which this variation in phenology affects overall flowering duration on a landscape, and the components of diversity that influence flowering duration, are unexplored. We investigate whether differences in flowering time due to topography yield an overall extension in duration of flowering resources in a northern California grassland. We recorded flowering time of pollinator resource species across four successive spring growing seasons (2015–2018) on paired north and south aspects. Flowering time differences were evaluated both at the community level and within species present on both paired aspects. The role of plasticity was examined in an experimental case study using genotypes of Lasthenia gracilis. We found that aspect is a strong determinant of phenology, with earlier flowering on warmer south‐facing slopes. Aspect differences resulted in complementarity in timing of flowering resources across sites, as aspects that started flowering earlier also ended earlier. Complementarity between north and south aspects served to extend the flowering time of pollinator resources by an average of 4–8 days (8%–15%), depending on the year. This extension can be attributed to both within‐species responses to aspect differences and species turnover. Flowering of L. gracilis genotypes was distinct across aspects, demonstrating that plasticity can drive the extension of flowering duration. Our findings indicate that heterogeneous topography can extend overall flowering time of pollinator resources, which may support pollinator biodiversity. Extension was most pronounced at the community level, which incorporates species turnover as well as plastic and genotypic differences within species.  相似文献   
69.
吕晓艳  刘霞  张媛 《昆虫学报》2021,64(10):1196-1204
【目的】入侵物种能够通过竞争影响本地物种的种群,从而影响入侵地的生物多样性。长足光捷蚁Anoplolepis gracilipes是全球最具破坏力的入侵蚂蚁之一。本研究旨在明确西双版纳地区入侵长足捷蚁与土著优势种蚂蚁黄猄蚁Oecophylla smaragdina之间的竞争关系。【方法】通过野外调查和室内控制试验相结合的方法,观察和对比分析长足捷蚁和黄猄蚁的体型大小,雾凉季和雨季的巢穴外觅食活动规律,觅食能力(搜寻食物的时间、在觅食时间内召集的最大工蚁数),打斗行为(不同打斗组合的攻击强度和死亡率)以及对饥渴的耐受性(无食物和水分供应时平均存活时间和存活率随时间的变化)。【结果】长足捷蚁工蚁体长(3.66±0.06 mm)显著小于黄猄蚁工蚁(8.27±0.16 mm)。在雾凉季时,长足捷蚁具有比黄猄蚁更长的觅食活动时间;而在雨季时,两种蚂蚁均在下午温度较高时段觅食活动的个体数量减少。苹果、蜂蜜和火腿肠3种食物作为诱饵时,长足捷蚁具有更快搜寻食物的能力,4~8 min便能找寻到食物,而黄猄蚁需要8~21 min才能找寻到食物,此外在寻找到食物后,长足捷蚁也有更快召集同伴的能力。在人工控制试验中,1头长足捷蚁和1头黄猄蚁同时存在时主要以不攻击和低强度攻击为主,而当两种蚂蚁中的任意其中一种的个体数量增加到5头时,攻击强度会显著增加,两种蚂蚁均存在种间协作行为。在饥渴状态下,两种蚂蚁工蚁的平均存活时间差异不显著,但长足捷蚁最长存活120 h,黄猄蚁最长存活96 h。【结论】在西双版纳地区,长足捷蚁相较于土著黄猄蚁具有更强的觅食的能力,雾凉季觅食活动时间更长,暗示长足捷蚁可能具有较强的温度适应能力。有必要加强对这一入侵蚂蚁的研究,并密切关注其种群在该地区的发展。  相似文献   
70.
采用样方法对不同资源位群落进行调查,通过冗余分析(RDA)结合Monte Carlo随机置换检验筛选出对桂林岩溶石山常绿落叶阔叶混交林乔木层优势物种分布影响显著的土壤资源轴(土壤有机质、土壤水溶钙、土壤速效氮、土壤全氮、土壤pH值和土壤厚度)。利用Levins生态位宽度指数和Pianka生态位重叠指数对桂林岩溶石山常绿落叶阔叶混交林乔木层14个优势物种在土壤有机质、土壤水溶钙、土壤速效氮、土壤全氮、土壤pH值和土壤厚度6个土壤资源轴上的生态位特征进行研究。结果表明:(1)在土壤有机质和土壤水溶钙资源轴上,生态位宽度最大值为常绿物种檵木(0.89、0.94);在土壤pH值资源轴上,生态位宽度最大值为常绿物种粗糠柴(0.96);在土壤速效氮、土壤全氮和土壤厚度资源轴上,生态位宽度最大值为落叶物种南酸枣(0.87、0.99、0.97)。(2)14个优势物种在6个土壤资源轴上,生态位重叠均值由大到小依次为土壤厚度 > 土壤全氮 > 土壤水溶钙 > 土壤速效氮 > 土壤pH值 > 土壤有机质,且均表现为常绿物种与常绿物种形成的种对生态位重叠均值(0.84) > 常绿物种与落叶物种(0.74) > 落叶物种与落叶物种(0.66)。(3)综合6个土壤资源轴,生态位重叠值≥0.5的种对高达480对,占总种对数的87.91%,暗示桂林岩溶石山常绿落叶阔叶混交林乔木层优势物种在资源匮乏且资源异质性高的特殊生境中存在激烈竞争,且乔木层种间关系相对不稳定。  相似文献   
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