基于CART的重庆烟区生态因子对烤烟经济性状的影响

发布时间：2018-05-27 11:19

本文选题：烤烟 + 生态因子　；参考：《西南大学》2017年硕士论文

【摘要】：烤烟是一种对生长环境十分敏感的经济作物,生态条件是烤烟生长发育及风味、品质形成的基本。重庆烟区是我国最适宜生产优质烟叶的产区之一,但重庆地理环境复杂,各生态因子均存在较大差异,烤烟经济性状水平参差不齐,使得明确各生态因子对烤烟经济性状的影响显得尤为重要。然而由于植烟村及可植烟旱地空间分布缺失,使其生态数据与植烟点位置难以对应,增加研究难度;相关系统性研究中缺乏按照烤烟在不同生育期对光照、气温和降水需求的不同,将气候因子分类的工作;且现代烟草农业建设对信息化技术和区域化管理需求也日益迫切。针对上述问题,本文通过调查研究、地统计学、相关分析、模糊c-均值聚类、单因素ANOVA检验和CART决策树等研究方法,系统分析了重庆烟区生态环境特征,将气候因子按烤烟生育期进行分类,进一步明确各生态因子与烤烟经济性状的关系。通过CART计算结果,将重庆烟区各生态因子对烤烟经济性状影响的相对重要性进行排序,进而筛选出烤烟生长的限制因子,为制定与当地生态条件配套的栽培管理及生产技术提供参考,有利于提高重庆烤烟资源的合理配置。主要结果如下:1.构建了重庆烟区气候因子、地质背景、地形地貌和土壤养分及烤烟经济性状的空间数据库并分析其特征,进而筛选出与烤烟经济性状显著相关的生态因子。重庆植烟村大田期的平均月日照时数为122.5 h,平均月均温为19.0℃,月均降水量为150.2 mm。各时期日照时数均表现为渝东北高于渝东南;均温以渝东南和少数渝东北地区较高,渝中相对偏低;降水量表现为南川、武隆和彭水较低,黔江和酉阳较高,巫溪的还苗伸根期降水量较低而成熟期降水量偏高。在海拔区间为600-1400 m的重庆植烟村旱地中,共包含30种地质岩层类型,三叠系大冶组灰岩白云岩面积最大,占总植烟面积的45.22%,其次为二叠系梁山组-吴家坪组灰岩白云岩;平均海拔为1010 m,平均坡度为17°,平均剖面曲率为5.21°,渝东南地区半阴坡和半阴坡所占比例较大,渝东北地区阴坡、阳坡大面积集中分布较多。土壤养分变异系数分析表明各养分空间差异较大。各时期日照和均温,成熟期和大田期降水,海拔,土壤pH值、总磷、有效S、有效Fe、有效Cu和有效Mn含量与烤烟产量呈极显著或显著相关;各时期日照,成熟期均温,成熟期和大田期降水,海拔、坡向、土壤pH值、交换性Mg、有效S、Cl、有效Zn和有效Mn含量与烤烟上中等烟比例呈极显著或显著相关。2.分别对烤烟产量、上中等烟比例进行分类,探讨了各生态因子对分类结果影响的相对重要性,从而明确了烤烟经济性状提高的限制因子。采用模糊c-均值聚类法,分别将烤烟产量、上中等烟比例分为3类。高产组具有日照时数和大田期降水较多、成熟期均温较低,海拔高,土壤pH、总磷和有效S含量较高且Mn含量较低的特征。优质组具有旺长期日照时数、成熟期降水较高,成熟期均温较低,海拔较高、阳坡半阳坡较多,土壤pH、交换性Mg含量较高且有效Mn含量较低的特征。高产或优质烤烟的地质岩层中灰岩白云岩所占比例均在70%以上。CART计算结果表明,各因子对烤烟产量影响的相对重要性排序为旺长期日照成熟期均温有效MnpH海拔大田期降水有效S总磷地质背景有效Zn有效Cu有效Fe,各因子对烤烟上中等烟比例影响的相对重要性排序为旺长期日照成熟期降水地质背景有效Mn成熟期均温海拔pH坡向交换性Mg还苗伸根期降水Cl有效S有效Zn。3.与烤烟经济性状呈极显著或显著相关的各生态因子在9类烤烟经济性状组合间均存在不同程度的显著差异,明确了其在具有不同产量(或上中等烟比例)特征的烟区中,对烤烟上中等烟比例(或产量)影响的生态因子相对重要性。高产优质、中产优质和中产中质样本比例较高,低产低质样本仅占总样本的1.64%。空间上,巫山高产优质烤烟样本比例最高(96.83%)。各植烟区县包含的烤烟类别越少,表明区域烤烟经济性状水平越集中、稳定,相反则表明该区域烤烟经济性状水平差异较大,应分别采取不同措施对烟田种植进行管理。在具有高产特征的经济性状组合中,气候条件和土壤养分对烤烟上中等烟比例的影响大于地形地貌和地质背景。在具有中产特征的经济性状组合中,气候条件对烤烟上中等烟比例的影响仍最大,但地形地貌因子和地质背景的影响要高于土壤养分。在具有低产特征的经济性状组合中,气候因子、土壤养分和地形地貌因子对烤烟上中等烟比例的影响相当。在具有优质和中质特征的经济性状组合中,地形地貌和气候因子是产量分类的主要原因。在具有低质特征的经济性状组合中,土壤养分成为影响烤烟产量分类的主要因素,地质背景对烤烟产量分类贡献最小。综上所述,本文通过分析重庆烟区生态因子与烤烟经济性状之间的关系,表明烤烟生长期的日照时数、降水量、海拔和土壤有效Mn含量对烤烟生长的影响较大。分析了各生态因子在不同产量、上中等烟比例分类及两者组合中的特征,明确了气候因子、地质背景、地形地貌和土壤养分对烤烟经济性状的影响,进一步筛选了导致烤烟经济性状差异的限制因素并对其贡献率排序,为重庆烟区优质特色烟叶的生产布局优化提供了重要参考。
[Abstract]:Flue-cured tobacco is a kind of economic crop which is very sensitive to the growth environment. The ecological condition is the basic of the growth and flavor of flue-cured tobacco and the formation of quality. The Chongqing tobacco area is one of the most suitable producing areas in China, but the geographical environment of Chongqing is complex, the ecological factors are different, the level of the economic characters of the flue-cured tobacco is uneven, making Ming dynasty clear It is very important that the ecological factors affect the economic characters of flue-cured tobacco. However, because of the lack of spatial distribution of the tobacco planting village and the dryland, the ecological data and the location of the tobacco planting point are difficult to correspond to, and the difficulty of the study is increased. The work of classification of climate factors; and the demand of modern tobacco agriculture construction on information technology and regional management is becoming increasingly urgent. Aiming at the above problems, this paper systematically analyses the ecological environment of Chongqing tobacco area through investigation, geostatistics, correlation analysis, fuzzy c- mean clustering, single factor ANOVA test and CART decision tree. The relationship between the ecological factors and the economic characters of flue-cured tobacco was further clarified. The relative importance of the ecological factors on the economic characters of the flue-cured tobacco in Chongqing tobacco area was sorted by the results of CART, and the limiting factors of the growth of the flue-cured tobacco were screened out to match the local ecological conditions. The cultivation management and production technology provide reference to improve the rational allocation of Chongqing flue-cured tobacco resources. The main results are as follows: 1. the spatial database of climate factors, geological background, topography and geomorphology and soil nutrients and the economic characters of flue-cured tobacco in Chongqing tobacco area were constructed, and the characteristics were analyzed, and the significant correlation with the economic characters of flue-cured tobacco was screened. Ecological factors. The average monthly sunshine time of Chongqing planting tobacco village was 122.5 h, the average monthly average temperature was 19 C, and the average monthly rainfall of 150.2 mm. was higher than that in the southeast of Chongqing; the average temperature was higher in Southeast Chongqing and in the northeast of Chongqing, and in Yuzhong was relatively low; the precipitation was South Sichuan, Wulong and Pengshui were lower. Qianjiang and Youyang are higher, the precipitation in Wuxi is low and the precipitation in mature period is high in Wuxi. In the dry land of 600-1400 m in Chongqing planting village, 30 types of geological strata are included. The area of the Triassic Daye group limestone dolomite is the largest, accounting for 45.22% of the total tobacco planting area, followed by the Permian Liangshan formation and Wu Jia Ping group limestone. The average altitude of the dolomite is 1010 m, the average slope is 17 degrees, the average section curvature is 5.21 degrees, the proportion of the semi shady slope and the half shady slope in the southeast of Chongqing is large. The large area of the sunny slope in the northeast of Chongqing is more concentrated. The analysis of the variation coefficient of soil nutrients shows that the spatial differences of the nutrients are large. Precipitation, elevation, soil pH, total phosphorus, total phosphorus, effective S, effective Fe, effective Cu and effective Mn content were significantly related to the yield of flue-cured tobacco, and all periods of sunshine, mature period, maturity and field precipitation, elevation, slope direction, pH value of soil, exchangeable Mg, effective S, Cl, effective Zn and effective Mn content were very significant with the proportion of medium smoke on flue-cured tobacco. The significant correlation.2. classifies the yield of flue-cured tobacco and the proportion of upper medium smoke respectively. The relative importance of the ecological factors to the classification results is discussed, and the limiting factors for improving the economic characters of the flue-cured tobacco are clarified. The fuzzy c- mean clustering method is used to divide the yield of Flue-cured Tobacco and the proportion of the upper middle and middle tobacco into 3 categories. There are more precipitation in Datian period, high altitude, high altitude, high altitude, high soil pH, high total phosphorus and effective S content and low Mn content. The high quality group has high sunshine duration, high precipitation at mature stage, lower average temperature in mature period, high altitude, high half Yang slope, soil pH, high exchangeable Mg content and low effective Mn content. The proportion of limestone and dolomite in the geological rock of high yield or high quality flue-cured tobacco is above 70%.CART calculation results show that the relative importance of the factors affecting the yield of flue-cured tobacco is the effective MnpH altitudinal precipitation effective S total phosphorus geological background with effective Zn effective Cu effective Fe, each factor on the flue-cured tobacco in the upper part of the flue-cured tobacco. The relative importance of the influence of the proportion of the equal smoke is in the period of the mature period of the sunshine maturity, the effective Mn mature period of the precipitation geological background, the pH slope, the exchange Mg, the precipitation Cl, the effective S, the effective Zn.3. and the economic characters of the flue-cured tobacco, which are significantly or significantly related to the economic characters of the 9 kinds of flue-cured tobacco. The relative importance of the ecological factors on the medium smoke ratio (or yield) on flue-cured tobacco, high yield and quality, high quality of middle middle and middle middle quality samples, and low quality and low quality samples in the 1.64%. space of the total sample, Wushan high yield and quality roasting. The proportion of tobacco samples was the highest (96.83%). The less the types of flue-cured tobacco contained in each tobacco planting area, the more concentrated and stable economic characters of the regional flue-cured tobacco, on the contrary, it showed that there was a great difference in the level of economic traits in the area. Different measures should be taken to manage the planting of tobacco fields. The effects of parts and soil nutrients on the proportion of medium smoke on flue-cured tobacco are greater than topography and geological background. In the economic character combination with middle middle characteristics, the influence of climate conditions on the proportion of medium tobacco on flue-cured tobacco is still the greatest, but the effects of topographic geomorphic factors and geological background are higher than soil soil nutrients. Climate factors, soil nutrients and topographic and geomorphic factors have the equivalent effect on the proportion of medium tobacco on flue-cured tobacco. In the combination of quality and medium characteristics of economic traits, topographic landforms and climatic factors are the main reasons for the classification of yield. In the combination of low quality characteristics of economic traits, soil nutrients will affect the yield classification of flue-cured tobacco. In this paper, the relationship between the ecological factors of Chongqing tobacco area and the economic characters of flue-cured tobacco was analyzed, and the effects of sunshine hours, precipitation, altitude and effective Mn content on the growth of flue-cured tobacco in the growth period of flue-cured tobacco were analyzed. The effects of climate factors, geological background, topography and soil nutrients on the economic characters of flue-cured tobacco were clarified, and the limiting factors leading to the difference of the economic characters of flue-cured tobacco were further screened and the contribution rate was sorted, which provided the optimization of the production layout of high quality tobacco in Chongqing tobacco area. An important reference.
【学位授予单位】：西南大学
【学位级别】：硕士
【学位授予年份】：2017
【分类号】：S572

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