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1.
We applied six measures of effectiveness to recent decisions about additional conservation areas in north-eastern New South Wales. Three have been widely used previously: (1) number of conservation areas; (2) total extent of conservation areas; and (3) representativeness (the proportion of natural features such as forest types or animal species represented in conservation areas to some targeted level). The other measures were: (4) efficiency or representation bias (the extent to which some features are protected above target levels at the expense of others that remain poorly protected); (5) relative protection of vulnerable areas within public land (percentage protection of flat, fertile areas relative to that of steep and/or infertile areas); and (6) relative protection of vulnerable areas across all tenures (the correlation between the amount of protection given to features and their vulnerabilities to clearing). We applied the measures in two chronological comparisons: the reserve system in 1994, 1996 and 1997; and before and after the Interim Assessment Process of 1996 which involved negotiations over new reserves and extensive unreserved areas that were temporarily deferred from logging. Over the study period, despite expansion of formal conservation and progress towards quantitative conservation targets, gazetted reserves remained strongly biased to the steep and/or infertile parts of public lands. Both gazetted reserves and areas deferred from logging increased the bias in protection away from forest types most vulnerable to clearing and for which regional conservation targets had already been most compromised. Two major challenges for future conservation decisions in the region are common to conservation planning generally: (1) to focus protection within public tenure on habitats and species most vulnerable to threatening processes such as logging; and (2) to provide more effective conservation management on private lands where loss of native vegetation continues.  相似文献   
2.
对甘蔗区域试验数据进行基因型与环境互作分析,有利于全面了解参试品种的丰产性和各试点的代表性,对优良新品种的推广和品种的区域分布也有着重要意义。本文综合利用AMMI模型和HA-GGE双标图对2014年国家甘蔗第10轮区域试验11个品种和13个试点的蔗茎产量和蔗糖产量数据进行产量稳定性和丰产性分析,评价试点的代表性和分辨力。结果表明:蔗茎产量和蔗糖产量在不同品种和试点间存在极显著差异,品种和试点存在极显著互作效应。‘福农40号’综合表现最佳,是产量高、丰产性好且蔗茎产量和蔗糖产量的稳定性均较强的品种;‘云蔗08-2060’的产量略低于‘福农40号’,但蔗茎产量和蔗糖产量的稳定性强于‘福农40号’;与对照品种‘ROC22’相比,‘粤甘43号’、‘粤甘46号’和‘闽糖02-205’的蔗茎产量和蔗糖产量较高,稳定性中等,‘福农40号’、‘粤甘43号’、‘粤甘46号’和‘云蔗08-2060’均具有较强的适应性,可在适宜蔗区推广应用。综合AMMI和HA-GGE双标图分析结果表明,广东遂溪、云南开远和福建福州具有较高的地点分辨力和试点代表性。因此,AMMI和HA-GGE双标图的综合运用,可更准确直观地评价出各品种的丰产性、稳定性和适应性以及各试点的分辨力和代表性。本研究可为甘蔗新品种的鉴定与推广提供有价值的理论参考。  相似文献   
3.
Rapeseed variety needs to be tested by regional trial in multiple sites for many years before being applied in market in China. Performants of rapeseed were affected by the interaction of sites and varieties. Evaluation of regional trials is very important for guiding rapeseed breeding. GGE (genotype main effects and genotype ​× ​environment interaction) biplot was used to evaluate yield, stability, adaptability, representativeness and discrimination of national winter rapeseed trials in the upper reaches of Yangtze River in 2017-2018. Results showed that the main effects of genotype (G), environment (E) and genotype ​× ​environment interaction (G × E) were significant (P ​< ​0.01) for yield. Among them, E accounted for 46.95% total variation on average, G and G × E accounted for 19.34% and 33.71% respectively. Eight varieties were found with high-yield, excellent stability and adaptability, including ‘Yiyou 29’, ‘Xiwang 920’, ‘Liyouza 108’, ‘Nanyou 546’, ‘Dadi 195’, ‘Jiayou 1’, ‘Huayouza 28’ and ‘Yuhua 2’. Test sites included Nanchong, Mianyang, Wanzhou, Shuangliu and Chengdu in Sichuan Province and Zunyi together with Guiyang in Guizhou Province were selected for their excellent representativeness and discrimination. These results would provide theoretical basis for rapeseed breeding.  相似文献   
4.
基于GGE双标图和马克隆值选择的棉花区域试验环境评价   总被引:1,自引:0,他引:1  
棉纤维马克隆值是与纤维成纱品质密切相关的重要品质指标,也是长江流域棉花品质改良的主要制约因子。选择利用对目标环境代表性强的试验点进行区域试验布局有助于提高马克隆值育种效率和节省试验成本。GGE双标图是进行试验点代表性评价和选择最有效的统计和图形展示工具,已经在多种作物区域试验中用于品种稳定性和试验环境相似性分析,但在基于马克隆值选择的棉花区域试验环境评价中应用报道较少。本文采用GGE双标图方法对2000—2010年期间27组长江流域国家棉花区域试验中的15个试验环境基于马克隆值选择的鉴别力、代表性和理想指数进行综合评价与分析。结果表明:各试验环境依理想度指数优劣排序为荆州市>黄冈市>南通市>九江市>岳阳市>射洪县>常德市>安庆市>武汉市>南阳市>南京市>慈溪市>襄阳市>简阳市>盐城市;从中筛选出最理想试验环境为湖北省荆州市,较理想试验环境为湖北省黄冈市、江苏省南通市和江西省九江市,这些试验环境对以长江流域为目标环境的广适性新品种选育和作为区域试验点鉴别理想品种的效率最高;而位于江浙沿海棉区的江苏省盐城市和浙江省慈溪市不适宜作为针对长江流域的马克隆值选择与推荐环境。本研究充分展示了GGE双标图在区域试验环境评价方面的应用效果,也为以长江流域棉区为目标环境的广泛适应性和特殊适应性品种的马克隆值选择和应用提供理论依据。  相似文献   
5.
重组自交系群体的检测调整方法及其在大豆NJRIKY群体的应用   总被引:23,自引:2,他引:21  
重组自交系(RIL)群体是遗传作图和QTL定位研究中常用的群体,构建过程中可能出现的异常偏分离会影响群体的使用。根据理论群体的分析,提出了用均等性、对称性和代表性3类χ2检验评价试验群体;利用代表性测验的家系最大χ2值和家系异常偏分离率调整异常偏分离的群体;并且应用计算机模拟方法编制了确定群体代表性测验参数  相似文献   
6.
基于地类分层的土壤有机质光谱反演校正样本集的构建   总被引:3,自引:0,他引:3  
以江汉平原滨湖地区不同土地利用类型的土壤样本为例,比较了基于目标土壤理化性质的浓度梯度法、扩展的基于多种理化性质的综合法(P-KS)、基于光谱信息的KS法、最邻近样本去除法(reduce nearest neighbor samples,RNNS)法和基于浓度分层并结合光谱信息的C-KS、C-RNNS法,基于地类分层再结合上述方法,构建具有不同层次土壤信息代表性的校正集,采用偏最小二乘回归法,建立土壤有机质可见光/近红外光谱反演模型。结果表明,具有单一代表性的浓度梯度法、KS法、RNNS法难以建立适用模型;具有光谱与理化性质二元代表性的C-KS方法模型预测精度得到了明显的提升,相对分析误差(ratio of performance to standard deviation,RPD)为1.66;考虑土地利用类型后,浓度梯度法、RNNS法与C-KS法模型预测精度有明显的提升,RPD分别达到了1.84、1.51、1.75,模型具有良好的适用性。说明具有多层次土壤信息代表性的校正集构建方法对提高土壤有机质可见光/近红外光谱反演模型的适用性具有较好作用。  相似文献   
7.
[Objective] This study was to evaluate the high yielding and stability of candidate cultivars, depict the adaptive planting region, analyze trial location discrimination ability and representativeness, as well as identify the ideal cultivar and trial location, with the aim to provide theory background for cultivar selection and reasonable scheme of test location in Jiangsu Province. [Method] The GGE biplot method was used to analyze the lint cotton yield of 12 experimental genotypes in the 6 test locations(three replicates in each) of the cotton regional trial in Jiangsu Province in 2013. [Result] The effects of genotype(G), environment(E), and genotype by environment interaction(G×E) on lint cotton yield were all highly significant(P0.01), which made it necessary to further explore the specific pattern of genotype by environment interaction. Jinmian118(G4) and SF3303(G5) were the best ideal genotypes screened by the "ideal cultivar" and "ideal location" view of GGE biplot, and the ordination of test sites based on the ideal index were in the order of Dafeng(DF), Yanliang(YL), Liuhe(LH), Dongtai(DT), Yancheng(YC), and Nantong(NT), among which NT was relatively weak in representing of the whole target cotton planting region in Jiangsu Province. The "similarity among locations" view of GGE biplot clustered all trial locations into one group, showing that the test sites in the cotton planting region in Jiangsu Province were in the same mega-environment.The "which-won-where" view of GGE biplot indicated that cotton cultivar Jinmian118(G4) was the most appropriate cultivar in the homogeneous cotton planting region in Jiangsu Province. [Conclusion] Among the candidate cultivars, Jinmian118 and SF3303 were identified as the most ideal cultivars in this set of conventional cotton regional trial in Jiangsu Province; the test site of Dafeng ranked the first out of all locations in terms of discrimination and representativeness, and all test locations were clustered into the same mega-environmet, which indicated the high efficiency of cultivar selection in the cotton regional trial in Jiangsu Province.  相似文献   
8.
We attempted to clarify the importance of obtaining representative soil samples for microbiological purposes by comparing results from composite samples and individual cores taken at a depth of 30 cm from four different treatments at the Static Fertilisation Experiment in Bad Lauchstädt, Germany. As enzyme activities can be related to microbiological activities, we analysed alkaline phosphatase, -glucosidase and protease activities from the composite and individual samples. When comparing both kinds of samples, protease activity was found to be the most and -glucosidase activity the least variable parameter. Comparing just the individual cores, the greatest variation was found for alkaline phosphatase and the lowest variation for -glucosidase activity; however, the latter enzyme activity also showed significantly different values. Thus, care should be taken when sampling in the field for microbial purposes.
Frank BöhmeEmail: Phone: +49-345-5585420Fax: +49-345-5585449
  相似文献   
9.
Aroma composition of blood orange juices obtained from Moro and Sanguinello (Citrus sinensis L. Osbeck) was analyzed by sensory and instrumental analyses. Liquid-liquid extraction with dichloromethane was used for extraction of volatile components. According to sensory analysis, the aromatic extract obtained by liquid-liquid extraction was representative of blood orange juice odour. A total of 83 and 78 aroma compounds, including alcohols, esters, terpenes, terpenols, aldehydes, acids, ketones, volatile phenols, and lactones were identified in the Moro and Sanguinello juices, respectively. Of these, 15 volatile components presented odour activity values (OAVs) greater than 1, with dl-limonene, nootkatone and linalool being those with the highest OAVs in both cultivars.  相似文献   
10.
孙孝林  王会利  宁源 《土壤》2014,46(3):439-445
基于样点代表性等级的土壤采样方法在成本、应用性、制图准确度上具有明显的优势,但在其他方面(如敏感性)上仍需要大量研究。为了进一步研究这种方法的可用性,本文以安徽宣城境内的丘陵山区为研究区,应用该方法分析以往土壤采样点的代表性等级,进而研究样点代表性等级对土壤制图准确度的影响。研究结果表明:①高等级代表性链广泛存在,而低等级代表性链则较少;②代表性链的等级有效地从不同程度反映出土壤形成环境的变异;③样点代表性采样设计的采样点与规则化网格采样、目的性采样有很大不同;④一般地,随着低等级样点的逐渐加入,制图准确度增加,但增幅随着样点等级的降低而降低。这些结果说明,样点代表性等级采样法在应用、成本、准确度几个方面都有明显的优点,因而具有较好的应用前景。需要注意的是,在应用该方法选择样点时,样点的代表性应达到一定级别,以避免制图准确度不会因为样点的加入而降低。此外,由于其他地形地貌类型(如平原区)还缺乏较好的土壤协同环境因子,该方法的应用受到了一定程度的限制。  相似文献   
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