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541.
C. Dustin?BeckerEmail author Ana?Agreda Evelyng?Astudillo Melina?Costantino Pascual?Torres 《Biodiversity and Conservation》2005,14(11):2695-2707
Monitoring of fog capture and bird communities helped to build social capital for conservation at Loma Alta, Ecuador and encouraged
the local community to protect 3000 hectares of tropical forest. Data collected during monitoring were used to facilitate
action and cooperation at local, regional, national, and international levels for conservation of biodiversity in western
Ecuador, including the designation of an Important Bird Area in the region. Through involvement with the monitoring efforts,
local people became more aware of the value of ecosystem services, learned about local birds and their conservation status,
became familiar with ecotourism, and began to include conservation of biodiversity with sustainable development planning in
their community. The context of monitoring, the objectives and participants, field methods, impacts in terms of conservation
action, and the costs and benefits of the two monitoring initiatives are described. 相似文献
542.
陕北黄土区狼牙刺水势研究 总被引:11,自引:3,他引:8
采用压力室水势仪,测定了陕北黄土区狼牙刺2~3年生小枝的水势。以柠条作对照,作了植物水势日变化、月变化动态研究。并分析了水势同光合有效辐射、大气温度、空气相对湿度(从CID-301PS光合测定仪获取)之间的相关关系。结果表明:狼牙刺水势日变化呈单峰曲线,最高值出现在12:00前后;一年中,从植物生长初期至盛期,水势绝对值表现出不断增加的趋势;狼牙刺水势同光照、气温有显著负相关性,与空气相对湿度有显著正相关性,而与植物年龄无密切关系。水势对比研究表明,狼牙刺较柠条耐旱。 相似文献
543.
Blooms of the nuisance alga Gonyostomum semen occurred in Lake 979 (Experimental Lakes Area), a small brown-water lake, that was subjected to several years of an experimental flooding regime. During periods of flooding, blooms of G. semen developed when light decreased below 100molm–2s–1 and total phosphorous concentrations increased to >30gl–1. Gonyostomum semen biomass was significantly correlated with total P and DOC concentrations. In addition, G. semen abundance increased at times when Daphnia rosea had rapidly declined to<10 animals l–1. Daphnia egg ratios suggest that declines in Daphnia abundance were the result of shifts in mortality and not causally linked to changes in G. semen densities. The results observed in Lake 979 were supported by a laboratory experiment where the appearance of G. semen from Lake 979 sediment was stimulated by altering chemical and biological variables. The stimulation of G. semen blooms appears to be dependant on multiple variables rather than a single variable. 相似文献
544.
Geographical diversity gradients, even among local communities, can ultimately arise from geographical differences in speciation and extinction rates. We evaluated three models—energy-speciation, energy-abundance, and area—that predict how geographic trends in net diversification rates generate trends in diversity. We sampled 96 litter ant communities from four provinces: Australia, Madagascar, North America, and South America. The energy-speciation hypothesis best predicted ant species richness by accurately predicting the slope of the temperature diversity curve, and accounting for most of the variation in diversity. The communities showed a strong latitudinal gradient in species richness as well as inter-province differences in diversity. The former vanished in the temperature-diversity residuals, suggesting that the latitudinal gradient arises primarily from higher diversification rates in the tropics. However, inter-province differences in diversity persisted in those residuals—South American communities remained more diverse than those in North America and Australia even after the effects of temperature were removed. 相似文献
545.
546.
Adrian Velazquez-Campoy Sonia Vega Oscar Sanchez-Gracia Angel Lanas Alberto Rodrigo Alagammai Kaliappan Melissa Barousse Hall Taylor Q. Nguyen Guy N. Brock Jason A. Chesney Nichola C. Garbett Olga Abian 《Biochimica et Biophysica Acta (BBA)/General Subjects》2018,1862(8):1701-1710
Background
Differential Scanning Calorimetry (DSC) is a technique traditionally used to study thermally induced macromolecular transitions, and it has recently been proposed as a novel approach for diagnosis and monitoring of several diseases. We report a pilot study applying Thermal Liquid Biopsy (TLB, DSC thermograms of plasma samples) as a new clinical approach for diagnostic assessment of melanoma patients.Methods
Multiparametric analysis of DSC thermograms of patient plasma samples collected during treatment and surveillance (63 samples from 10 patients) were compared with clinical and diagnostic imaging assessment to determine the utility of thermograms for diagnostic assessment in melanoma. Nine of the ten patients were stage 2 or 3 melanoma subjects receiving adjuvant therapy after surgical resection of their melanomas. The other patient had unresectable stage 4 melanoma and was treated with immunotherapy. Two reference groups were used: (A) 36 healthy subjects and (B) 13 samples from 8 melanoma patients who had completed successful surgical management of their disease and were determined by continued clinical assessment to have no evidence of disease.Results
Plasma thermogram analysis applied to melanoma patients generally agrees with clinical evaluation determined by physical assessment or diagnostic imaging (~80% agreement). No false negatives were obtained from DSC thermograms. Importantly, this methodology was able to detect changes in disease status before it was identified clinically.Conclusions
Thermal Liquid Biopsy could be used in combination with current clinical assessment for the earlier detection of melanoma recurrence and metastasis.General significance
TLB offers advantages over current diagnostic techniques (PET/CT imaging), limited in frequency by radiation burden and expense, in providing a minimally-invasive, low-risk, low-cost clinical test for more frequent personalized patient monitoring to assess recurrence and facilitate clinical decision-making. 相似文献547.
在上海迪士尼乐园项目中,风景园林师所供职的专业被称作场地开发(Area Development)。作为承担迪士尼乐园景观设计任务的重要专业,理解其内涵及运作方式对了解迪士尼乐园的景观营造有着十分重要的意义。本文着重通过比较分析场地开发专业与风景园林专业之间的异同来明确其概念范畴与核心诉求,从而总结出该专业在营造迪士尼乐园景观方面的特色之处,以期对中国主题公园乃至其他类型的公园绿地建设提供借鉴。 相似文献
548.
Fabio Spadi 《Ocean Development & International Law》2013,44(3):285-302
Abstract World fish resources, fishing methods, and processing operations in the seafood industry are described. The fishery situation in developing countries (LDCs) is discussed, with particular reference to artisanal and other local fisheries, and examples are cited to illustrate the structure of the industry. Technology transfer from developed countries to LDCs is discussed and recommendations are presented for future technology transfer programs. It is concluded that an integrated complex of small projects with defined, attainable objectives and immediate impact on income and food supply of the LDC populations is likely to be more successful than large‐scale programs with little immediate payoff. A case study of fisheries in two developing countries, Thailand and Peru, and extensive tabulation of statistical data on catches, value of catch, and unit value of fish species groups for selected countries, with a discussion of the significance of the data, are presented in an appendix. 相似文献
549.
550.
尾矿废弃地是一种极端的生态系统,其植被恢复的研究将丰富传统的生态学理论。该研究通过野外植被调查与室内萌发实验相结合的方法,探讨了兰坪铅锌矿区植被恢复初期不同群落类型地上植被、土壤种子库及其相互关系。结果显示:(1)与对照群落(云南松林、高山栎灌丛)相比,尾矿区恢复期各群落(早熟禾人工草地、魁蒿群落、马桑灌丛)地上植被及土壤种子库的物种数、物种多样性均较低。(2)植被恢复时间较短的2个群落(魁蒿群落、人工草地)土壤种子库较地上植被物种多样性高。(3)尾矿区恢复期各群落地上植被及土壤种子库的优势种均主要由风播、种子繁殖的植物组成,菊科、禾本科占较大比例,这些植物在尾矿区植被恢复初期起重要作用。(4)尾矿区恢复期各群落土壤种子库与地上植被的物种相似性较高,各群落之间地上植被及土壤种子库的相似性则较低。研究表明,尾矿区恢复初期土壤种子库与地上植被紧密联系,群落改造方式、恢复时间对土壤种子库具有重要影响。 相似文献