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1.
为了提高贵德梨果的栽培经济效益,本研究选取贵德名优农产品中取得地理标志的产品贵德软梨,开展了“气候好”农产品气候品质认定,确定了评价指标。采取综合认证方法,考虑影响农产品生长的生态适应性、当年的气候条件、管理水平和当年水果品质情况所占的比重,赋予不同的权重。并对各项分析打分,得到综合分数来确定。选取2020年贵德县园艺场的软梨进行了认定指标评价,结果表明2020年贵德县园艺场光热资源丰富、水分条件适宜、光热水匹配良好、气候优势明显,有利于优质软梨生产,2020年出产的贵德软梨气候品质等级为“特优”。  相似文献   

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The purpose of this paper is to construct monthly manufacturing output indexes for a metropolitan area, employing a method used by the Federal Reserve Banks to construct regional manufacturing indexes. The Tulsa metropolitan area is the region considered. The index of total manufacturing output is included in a vector autoregression model of the Tulsa economy. The results indicate that the linkages between manufacturing activity and non-manufacturing employment differ from the linkages between employment in those sectors, and that since the early 1980s both sectors have become less sensitive to changes in the price of oil.  相似文献   

4.
线性混合模型最佳线性无偏预测(BLUP)不仅适用于数据不平衡和误差方差异质试验的分析,而且对随机效应的排序会更准确。在实际试验分析中由于真实方差参数值未知而采用估计值时,BLUP转变为所谓经验性BLUP(eBLUP)。为了探讨eBLUP在作物区域试验品种评价的效果,本文以我国2012—2014年长江流域油菜区域试验12套产量资料为例,对eBLUP在品种主效应和特定环境中效应的估计、排序及差异比较t测验等方面与方差分析综合比较。结果表明,对品种主效应,eBLUP与方差分析算术平均值仅有较小差异,品种排序在eBLUP与算术平均值法相同;对特定环境中品种效应,eBLUP与算术平均值法有较大差异,品种排序在eBLUP较算术平均值法更准确;用Kenward-Roger法估算基于eBLUP的效应差异t测验的自由度,无论对品种主效应还是对特定环境中品种效应,eBLUP和方差分析有着相近的显著性(α=0.05)测验效果。  相似文献   

5.
Against the backdrop of aggravating resource and environment restriction,it is an inevitable choice to adopt the sustainable development pattern to maximize social well-being within the ecological threshold.From the perspective of ecological well-being performance,ecological footprint per capita and human development index were selected to construct the evaluation index system for sustainable urban development,and DEA applied to calculate the input-output efficiency,so as to analyze the sustainable development level of Shanghai from 1999 to 2012.The results showed that①human development index,ecological footprint per capita of Shanghai grew in step with economic development,but ecological footprint per capita level exceeded the ecological carrying capacity,thus the overall ecological conditions remained in the state of worsening deficit;②ecological well-being performance of Shanghai in most years remained in the DEA ineffective state,and the scale return had decreased gradually since 2005.In addition,the paper gave pertinent suggestions.  相似文献   

6.
To establish valid indexes for streetscape visual evaluation, this paper proposed 6 quantitative indexes to refl ect objective visual properties of streetscapes based on the image processing concept, and took real digital images of 10 pedestrian streets to verify the validity. Mathematical analysis of subjective and objective indexes showed that street width/height ratio, street width, sky openness index, visual entropy and color richness index could refl ect objective visual properties of streetscape(correlation coeffi cient r > 0.633, signifi cance P < 0.05); visual complexity accounted for the highest percentage in the evaluation conclusion(22.6%), so it was the most signifi cant infl uence factor.  相似文献   

7.
不同基因型萝卜品质指标的评价分析   总被引:2,自引:0,他引:2  
以11个不同基因型的萝卜为试材,在分析表观形态指标的基础上,研究肉质根水分含量、蛋白质含量、维生素C含量、色素在表皮的含量、木质素含量、氨基酸成分及含量等品质指标。最后用模糊数学隶属函数法,依公式X(u)=(X-Xmin)/(Xmax-Xmin)计算不同基因型的萝卜每个品质指标的隶属函数值,对其肉质根的营养品质进行综合评价,结果表明,板叶卫青和翠绿水果萝卜综合营养品质突出,德高青萝卜、潍县青萝卜和胶蔬大青萝卜的综合营养品质居上。  相似文献   

8.
旨在研究不同处理方式对青贮稻秸秆发酵的影响和青贮稻秸秆对山羊生长性能和血液生化指标的影响。在稻秸中加入乳酸菌、纤维素酶和糖蜜进行混合青贮,结果发现:在稻秸秆中添加2.5 g/t 乳酸菌、600 g/t 纤维素酶、4%糖蜜和加水200 kg/t 进行混合青贮能够降低pH(P<0.01)、丁酸和丙酸浓度(P<0.05);显著提高干物质(P<0.01)、粗蛋白(P<0.05)和可溶性碳水化合物(P<0.01)含量,而粗脂肪、中性洗涤纤维和酸性洗涤纤维则相反。将青贮稻秸替代30%、60%和100%粗饲料进行饲喂山羊。结果显示:替代100%组羊的末重和平均日增重显著高于其他各组(P<0.01),料重比最低;各组的平均日采食量无显著差异。替代60%组山羊的血清碱性磷酸酶浓度(P<0.01)和总胆固醇含量(P<0.05)均显著降低。综上所述,稻秸秆中添加2.5 g/t 乳酸菌、600 g/t 纤维素酶、4%糖蜜和加水200 kg/t 进行混合青贮的效果较好,且青贮稻秸代替100%粗饲料能够提高山羊的生长性能,降低成本  相似文献   

9.
应用高稳系数法综合评价甜玉米区试品种的高产稳产性   总被引:1,自引:0,他引:1  
以12个甜玉米品种区域试验产量数据为材料,采用常规的产量稳定性分析方法和高稳系数法对各甜玉米品种的高产稳产性进行了统计分析.结果表明:各参试品种的产量高稳系数与产量呈极显著的正相关,与产量变异系数呈极显著负相关;常规产量稳定性分析中的回归系数与产量相关性不明显,但与产量标准差和变异系数呈极显著负相关.研究表明,高稳系数可以作为甜玉米品种区域试验中高产稳产性的评价的指标.  相似文献   

10.
为获得合理的夏玉米灌溉控制指标,基于2 年控制试验结果,借助加权灰色关联综合评价法对夏玉米的耗水量、产量和水分利用效率(WUE)进行综合性评价。结果表明,与各处理的实测产量、耗水量、WUE 从高到低排序相比,产量、耗水量、WUE 的单层次评价值位次基本相同,对于优选夏玉米的干旱胁迫控制指标具有可行性。随干旱胁迫程度的增加,产量、耗水量评价值呈减小趋势;WUE 评价值呈先增加后减小趋势。多层次综合评价结果显示,WUE 的权重最大。随干旱胁迫程度的增加,综合评价值呈减小趋势,相同生育期内轻旱胁迫处理表现最优。2 年控制试验中,对照适宜水分处理最优,灌浆期轻旱处理次之,再次为苗期轻旱处理。考虑河南地区夏玉米生产实际,建议苗期、拔节期、抽雄期与灌浆期分别控制土壤水分下限保持在田间持水率的60%、70%、75%、60%以上时,可保证夏玉米节水稳产。该结论为河南省水资源高效利用提供理论参考。  相似文献   

11.
本文旨在研究丙氨酰谷氨酰胺(Ala-Gln)对断奶仔猪生长性能和血清生化指标的影响。试验选择大长白二元杂交仔猪48头,21 d断奶,随机分成4组,每组6个重复,每重复2头(公母各1头)。A组为对照组,饲喂基础日粮;B、C和D组为试验组,分别饲喂在基础日粮添加0.1%、0.3%和0.5% Ala-Gln的日粮,试验期20 d。结果表明,在21 d断奶仔猪日粮中添加0.1% Ala-Gln可显著提高21~31 d仔猪的平均日增重和饲料转化率(P<0.05),添加0.1%、0.3%和0.5% Ala-Gln可在正常生理范围内降低仔猪血清葡萄糖、甘油三酯、总胆固醇和尿素氮含量,提高仔猪血清总蛋白含量,随着日粮中Ala-Gln添加水平提高,21~31 d仔猪的平均日增重和饲料转化率均以二次曲线方式升高(二次,P=0.042和0.043),31和41 d血清葡萄糖含量、31 d血清甘油三酯、总胆固醇和尿素氮含量以线性方式下降(线性,P=0.034,0.001,0.008和0.001)。添加0.3%Ala-Gln就可达到理想的促生长效果。提示Ala-Gln可提高断奶仔猪生长性能。  相似文献   

12.
华莱士瓜含糖率农业气象指标体系,是定量评价其品质优劣的基础,更是华莱士瓜农业气象业务服务的基础。在解释华莱士瓜农业气象指标内涵的基础上,参照华莱士瓜农业气象指标体系构建的通则,综合农业气象指标研究方法的优缺点,确定关键生育期温度、水分、湿度、蒸发等农业气象指标。20个通过0.01显著水平检验的因子,6个通过0.05显著水平检验的因子。所选因子生物学意义与农业气象学意义明显,符合生产实际。将所有指标划分为最适宜、次适宜、不适宜。便于农业气象服务工作开展。评估模型通过0.01的显著性检验,拟合率达94.4%,拟合效果较好,可用于华莱士瓜品质评估。  相似文献   

13.
ABSTRACT Existing studies of convergence across jurisdictions of a nation have focused on developed economies. A key assumption underlying regional convergence is geographical factor mobility, and in a developed economy, mobility is facilitated by low transportation costs. By the same token, convergence in a less-developed economy may be impeded by the absence of a well-developed transportation infrastructure. We examine the rate and industrial composition of economic convergence in a neighboring less-developed country (LDC), Mexico, to examine how it might have differed from the U.S. experience. We find evidence of stronger convergence in Gross State Product per capita in Mexico relative to existing estimates of U.S. convergence. Further, while manufacturing activity has been found to be a primary source of convergence in the U.S., we find weaker evidence of convergence of manufacturing activity in Mexico. On the other hand, industries such as hotels and transportation were found to be significantly influential in regional convergence in the Mexican economy.  相似文献   

14.
食物安全的内涵、指标与评价方法综述   总被引:1,自引:0,他引:1  
食物安全问题一直是国内外研究的热点。目前,全球食物安全面临严重挑战,前景并不乐观。作为世界上人口和食物消费最大的国家,中国的食物安全面临更大挑战,但对其认识学术界还存在争论。为了准确把握食物安全的内涵,科学评价中国食物安全的状况,首先分析了食物安全概念的演变,然后总结了评价食物安全状况的供需平衡指标、消费指标、营养指标、综合指标,以及评价粮食安全状况的常用指标。随着人民生活水平的提高,中国的食物结构发生了根本的改变,因此,今后食物安全的研究应由单纯的粮食安全转向包括所有食物种类的食物安全,内容应更注重食物综合保障能力及营养安全。  相似文献   

15.
Salinity is a widespread soil problem limiting productivity of oilseed crops worldwide. Reduction in growth generally associated with decline in photosynthesis. Accumulation of osmo‐protectants such as glycinebetaine (GB) permits the plant to cope with salt stress. This study was aimed to understand the mechanism by which exogenous GB application improves photosynthetic capacity and salt tolerance in two diverse lines of canola differing in salt tolerance using chlorophyll fluorescence technique. Glycinebetaine was applied as foliarly or through rooting medium to two canola lines Dunkeld and Cyclone that were grown under non‐saline or saline conditions. Root‐applied GB caused adverse effects whereas foliar application of GB was effective in improving growth of canola cultivars. However, the response of salt‐tolerant cultivar Dunkeld was stronger than that of salt sensitive Cyclone. Foliar application of GB improved accumulation of proline and plant water status. Application of GB enhanced the photosynthetic CO2 fixation, stomatal conductance (gs) and water‐use efficiency. The tolerant lines Dunkeld had more responsive to GB application. Chlorophyll fluorescence measurements (Fo, Fm, Fv, Fo/Fm, Fv/Fo and Fv/Fm ratios) revealed that salt stress reduced energy trapping efficiency by damaging oxygen evolving complex, over reduction of QA resulting in occurrence of chronic photoinhibition. However, exogenous GB protected the oxygen evolving centre of PSII and maintains activity of PSII. Although root‐applied GB adversely affected the growth of canola plants, it did not have any adverse effect on PSII photochemistry. Moreover, fluorescence parameters could provide a rapid means for determining salt tolerance in canola and could be a rapid and sensitive test to identify genotypes highly tolerant to salt stress.  相似文献   

16.
区域土壤环境质量的可拓物元评价   总被引:2,自引:1,他引:1  
为了更加客观评价区域土壤环境质量,使土地资源得到合理规划和利用,将物元法引入土壤环境质量评价体系中,构建土壤环境质量评价的物元模型。通过实地土壤取样、测量,用物元分析法得出土壤中各种影响因子对一定区域内土壤环境质量的影响程度。实验结果表明:评价区内土壤中Cu含量为II级,其他重金属含量均符合I级标准,综合土壤环境质量评级结果为I级,具体等级值为1.342,即精确的等级是介于I级和II级之间,更偏重于I级。该评价方法可以科学、有效地应用监测数据,评价结果较为可信,能较科学地判定土壤环境质量级别,同时也可反映各污染因子对土壤环境质量的影响程度,并对污染程度加以区分和量化。  相似文献   

17.
There are a lot of evaluation approach on Regional Tourism Competition,such as Analytic Hierarchy Process(AHP),Data Envelopment Analysis(DEA),Principal Component Analysis(PCA),Fuzzy Cluster Analysis(FCA) and so on,but so far there is less research on valuation approach on Regional Tourism Competition via SEM.This paper has constructed an evaluation model about Regional Tourism Competition via the result of 5 Factors model on Regional Tourism Competition via SEM.  相似文献   

18.
甘蔗品种抗旱性光合生理指标及其综合评价   总被引:26,自引:0,他引:26  
利用相关、主成分、聚类和判别分析, 研究有关生理生化指标与甘蔗抗旱性关系. 结果表明: (1)中度水分胁迫下, MDA含量和PMP有不同程度地提高, 而Fv/Fm、 Fv/Fo、ΔFv/Fo、ΔFv/Ft和T1/2 有不同程度地降低, 变化的幅度因供试品种基因型而异. (2)PMP与MDA含量呈极显著正相关, 而与Fv/Fm、 Fv/Fo及ΔFv/Fo呈显著负相关; Fv/Fm与F  相似文献   

19.
为了能在双模态超燃冲压发动机流道方案初步论证中提供一种较快速的发动机性能计算方法,在二维N-S方程基础上,引入一维完全燃烧计算方法,提出了预估超燃冲压发动机性能的准二维计算方法。该方法能够计入激波、边界层分离等对发动机性能的影响,可在较短时间计算出整机推力、比冲性能和沿程热力学参数。通过对自由射流发动机计算,验证了此方法。并在此基础上,初步分析了燃料喷注位置和流道构型对发动机性能的影响。   相似文献   

20.
In-situ experiments and investigation of evaluation indexes were performed to study the subway-induced ground-borne noise in buildings along the subway lines. The characteristics of ground-borne noise in buildings were summarized from various aspects by analyzing the experimental data. The factors such as the spectrum width, the analyzing time and background noise effect on the results of evaluation indexes, were further investigated. The correlation between different evalution indexes was analyzed, and the deficiencies of the indexes of noise evaluation in the environmental noise control codes of China were discussed.  相似文献   

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