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51.
52.
Reclaiming Applied Anthropology: Its Past, Present, and Future 总被引:1,自引:0,他引:1
Growing concerns about anthropology's impact in both academia and the broader social arena have led to calls for more "public" and more relevant anthropology. In this article, we expand on these exhortations, by calling for systematic joining of critical social theory with application and pragmatic engagement with contemporary problems. We argue for the repositioning of applied anthropology as a vital component of the broader discipline and suggest that it should serve as a framework for constructing a more engaged anthropology. In revisiting disciplinary history and critiques of applied anthropology, we demonstrate the central role that application has played throughout anthropology's evolution, address common misconceptions that serve as barriers to disciplinary integration, examine the role of advocacy in relation to greater engagement as well as the relationship of theory to practice, and conclude with an assessment of the diverse work that is subsumed under the inclusive rubric of "anthropology in use." 相似文献
53.
54.
Choosing the right molecular genetic markers for studying biodiversity: from molecular evolution to practical aspects 总被引:3,自引:1,他引:2
The use of molecular genetic markers (MGMs) has become widespread among evolutionary biologists, and the methods of analysis
of genetic data improve rapidly, yet an organized framework in which scientists can work is lacking. Elements of molecular
evolution are summarized to explain the origin of variation at the DNA level, its measures, and the relationships linking
genetic variability to the biological parameters of the studied organisms. MGM are defined by two components: the DNA region(s)
screened, and the technique used to reveal its variation. Criteria of choice belong to three categories: (1) the level of
variability, (2) the nature of the information (e.g. dominance vs. codominance, ploidy, ... ) which must be determined according
to the biological question and (3) some practical criteria which mainly depend on the equipment of the laboratory and experience
of the scientist. A three-step procedure is proposed for drawing up MGMs suitable to answer given biological questions, and
compiled data are organized to guide the choice at each step: (1) choice, determined by the biological question, of the level
of variability and of the criteria of the nature of information, (2) choice of the DNA region and (3) choice of the technique. 相似文献
55.
起源于中国的栽培植物 总被引:2,自引:0,他引:2
中国是农业古国和大国,种植的作物约有840种,其中很多起源于本国。本文汇集起源于中国的作物为420种,涉及栽培物种553个。这些信息对中国作物种质资源研究和生物多样性保护有重要意义,并且可为国家制定生物多样性保护政策提供支撑。 相似文献
56.
利用DNA ISSR分子标记技术对芍药属植物栽培品种的分类鉴定方法 总被引:2,自引:1,他引:1
以利用DNA ISSR分子标记逐级区分品种为主要研究目标,通过ISSR引物的设计与实验筛选,取得了进展。该方法类似于经典的植物形态检索表式的分类策略,不同之处在于利用基因组DNA分子性状作为品种分类的依据,即"ISSR引物结合位点"与"DNA ISSR片段长度差异"的组合信息。该方法不仅可以有效鉴定品种,而且可以很容易地生成富含遗传变异信息的0、1矩阵,通过运算揭示品种间的遗传关系与演化规律。该方法成本低廉、操作便捷,对于建立客观、科学的牡丹及芍药品种分类体系,对于芍药属品种种质资源的保存、评价与合理利用具有重要价值。应该加大支持力度推进其实际应用。 相似文献
57.
不同土壤培肥措施对华北高产农田原生动物丰度的影响 总被引:5,自引:0,他引:5
为了解华北高产农田生态系统中秸秆还田、有机肥和化肥投入水平等土壤培肥措施对原生动物群落丰度的影响,1999年10月~2000年9月在山东桓台冬小麦套种夏玉米的田间试验中进行了取样分析。田间处理1~处理9,依序为:全还,麦还,全还 化肥1,麦还 化肥1,全还 化肥2,麦还 化肥2,全还 化肥3,麦还 化肥3和全还 化肥1 有机肥处理。应用3级10倍环式稀释培养法对土壤中鞭毛虫、纤毛虫、肉足虫3类群原生动物的丰度进行了测定。结果显示:该研究地块肥力状况良好;土壤鞭毛虫和肉足虫占有绝大比例,分别为总丰度的39.47%和59.22%,纤毛虫仅占1.31%;土壤原生动物丰度在不同培肥处理中表现出相似的季节性动态变化特征;比较不同土壤培肥措施条件下的原生动物丰度水平为:全还>麦还,全还 化肥1 有机肥>麦还 化肥1,麦还 化肥2,麦还 化肥3>全还 化肥1,全还 化肥2,全还 化肥3;化肥对原生动物丰度表现出明显的抑制作用,而有机肥对原生动力丰度表现出明显的促进作用。化肥的施用量水平对土壤原生动物丰度的影响无显著性差异,作物秸秆采取何种还田方式对土壤原生动物丰度的影响也是不显著的,如麦还 化肥培肥地块的原生动物丰度仅略高于全还 化肥。 相似文献
58.
《发酵工程与设备》课程设计是重要的实践教学环节, 在实践教学中起到承上启下的作用, 可为学生毕业后到工厂工作打下良好的工作基础。对课程设计所处地位以及教学观念、内容、方法等教学各环节进行交流探讨。 相似文献
59.
经营措施对青檀人工林生物量及檀皮产量的影响 总被引:10,自引:1,他引:9
调查了青檀人工林不同经营措施对林分地上部分生物生产力及檀皮产量的影响.结果表明(1)在密度及墩龄相同条件下,单位面积檀皮产量与年龄成正比,出皮率与年龄成反比;(2)单位面积檀皮产量年增长以第3年为最高,分别是第2年和第4年年增长量的1.58倍和4.12倍;(3)在密度、留萌数及萌发年龄相同条件下,单位面积檀皮产量以条墩年龄12年为最高,分别是6年生和9年生的3.32倍和1.11倍;(4)四种造林密度类型(2500、3333、4200和5350墩/hm2)中,檀皮产量大小顺序为4200>3333>5350>2500.4200墩/hm2(株行距1.4m×1.7m)的林分檀皮产量是2500墩/hm2(株行距2m×2m)林分植皮产量的1.68倍;(5)在密度、墩龄相同条件下,每墩留萌数为10时,单位面积植皮产量最高.从收获经济生物量(檀皮)的角度考虑,青檀人工林密度应在3333~4200墩/hm2之间,轮伐期为3年;在条墩年龄为9年以上的人工林中,留萌数以10条为好. 相似文献
60.
CH4 emissions from rice paddies managed according to farmer's practice in Hunan, China 总被引:2,自引:0,他引:2
We measured CH4 emissions from ricepaddies managed by farmer's practices inChangsha, Hunan Province, China, from 1995 to1997. During the winter season, rice fieldswere left fallow under either drained(C-Fallow) or flooded conditions (C-Flood), andplanted with either Chinese milk vetch (C-GM)or oil-seed rape (C-Rape). The organic manureproduced in the winter (weeds, Chinese milkvetch, or oil-seed rape straw) was incorporatedin situ before the early-ricetransplanting. Both early-rice and late-ricestraws were removed and the soil was notamended with any exogenous organic manure. For1996 to 1997, the average seasonal CH4emission for the double rice cropping periodwas the highest from the plot that was floodedin the winter (103.5 g CH4 m–2) andlowest from the plot planted and incorporatedwith Chinese milk vetch (32.6 gCH4 m–2). Precipitation in the winternot only affected growth of green manure, whichwas incorporated in situ, but might alsoaffect CH4 emissions during the subsequentrice growing period. Therefore, a simplerelationship could not be found between theincorporated amount of green manure andCH4 emission. In the plots incorporatedwith vetch and oil-seed rape straw CH4emissions were significantly less during thesubsequent late-rice period than during theearly-rice period. This phenomenon might beattributed to a ``priming effect' of greenmanure, which exhausted soil labile organicmatter. Based on the CH4 fluxmeasurements, the total CH4 emissions fromrice fields in Hunan Province during the ricegrowing season were estimated as 1.56 TgCH4 in 1996 and 1.06 Tg CH4 in 1997.Large variation of precipitation in the winterwould be an important factor controlling theannual variation of CH4 emissions from thetreatments. 相似文献