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山东农业大学学报（自然科学版）

山东农业大学学报（自然科学版）

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Journal of Shandong Agricultural University(Natural Science Edition)
本学报为农业综合性学术刊物，国内外公开发行。主要登载农学、园艺、植保、动物科技、林学、资源与环境、食品科学、农业工程、农业经济、生命科学、生物技术、水利及土木工程等方面的最新研究成果。属首届全国优秀科技期刊，被国内外30多家文摘类期刊及数据库收录，并已加入《中国学术期刊（光盘版）》、“中国期刊网”及“万方数据资源系统（ChinaInfo）数字化期刊群”。
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  • 国内刊号/CN：37-1132/S
    国际刊号/ISSN：1000-2324
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  • 主管单位：山东省教育厅
    主办单位：山东农业大学
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  • 主编：张宪省
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  • 地址：山东省泰安市
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山东农业大学学报（自然科学版）-获奖情况
  • • 首届N/T类核心期刊
  • • 1992年，该刊被国家科委、中宣部、新闻出版署评为全国优秀科技期刊
  • • 1992、1995年两次获农业部全国高等农业院校优秀学报一等奖
  • • 1995年获全国高校自然科学学报二等奖
  • • 1996年被评为山东省优秀科技期刊
  • • 1997年被评为华东地区优秀期刊
  • • 1999年被评为泰安市十佳期刊
  • • 1996年起连续5年入选中文核心期刊，2014年获中国高校优秀科技期刊和编辑创新奖，2016年获科技论文在线二等奖。2018年获中国高校优秀科技期刊奖
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山东农业大学学报（自然科学版） >2021年第6期

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  • 摘要：本文通过文献法和层次分析AHP法对所调查古城植物景观状况作初步分析,对塑造古城植物景观特色的构成要素进行分解,并对这些构成要素进行重要性排列,以期为以后的古城植物景观特色营造提供参考依据.%This article the literature search procedure and the analytic hierarchy process to investigate the plant landscape condition of the ancient city to mak the preliminary analysis, to molds the plant landscape characteristic s elements of ancient city to carry on the decomposition, and carried on the important arrangement to these elements, so as to provide the reference of the later plant landscape characteristic design to ancient city.
  • 摘要：利用流体模拟软件FLUENT中的DPM模型对喷杆喷雾机喷头的外流场进行数值模拟,建立不同外界条件下喷雾模拟的模型,获得田间作业时的最佳压力与风速.在模拟基础上进行了样机试验,得出实际最佳作业参数与模拟结果相符.试验结果证明,使用仿真技术,效果理想,可以为揭示小型喷杆喷雾机喷头的喷雾性能、质量及其影响因素提供理论依据,提高试验效率,节约成本,克服了自然条件对试验的局限性.%In order to obtain the best pressures and wind velocity in the fieldwork, a lot of spray simulation models about different exterior conditions are constructed to numerically simulate the suspended - type boom spraying machine shower nozzles exterior field based on the DPM model in FLUENT. The experiments are completed on the foundation of the simulation, the practical result agrees with the simulated result. The experiment result shows, constructing the models with the simulation technology is reasonable and can be used to provide the basis for the after experiments. Besides, this technology can reveal stem spray performance, quality and its influence factors of small suspended - type boom spraying machine, enhance the experiment efficiency, save the costs, shorten the cycle time and overcome the experiment limitations in natural conditions.
  • 摘要：Whether square matrix can be digitalized is an important nature of matrix. The comprehension to the necessary and sufficient condition of square matrix has been a difficulty problem in linear algebra. In this paper, a nature of the diagonalizable matrix is given and proved by using relevant conclusions of the rank of matrix. In fact, itS also a sufficient condition of diagonalizable matrix.%方阵是否可以对角化,是矩阵的一条很重要的性质.对方阵可对角化的充要条件的理解,一直是线性代数学习中的一个困难问题.本文利用矩阵秩的相关结论,给出并证明了可对角化矩阵的一个性质.事实上,它也是可对角化矩阵的一个充分条件.
  • 摘要：利用热扩散茎流测定系统(TDP)连续监测苹果树在生长季的茎流速率,同步观测太阳辐射、空气温度、空气相对湿度和风速等气象因子,选择晴天、阴天两种典型天气分析鲁西南地区苹果树干茎流速率的日变化及其与气象因子的关系.结果表明:苹果树干茎流速率在晴天条件下呈现单峰曲线,阴天条件下呈现多峰曲线.不同天气条件下,苹果树干茎流速率日变化波动曲线及其主要影响因子各异,但太阳辐射始终是茎流速率变化的主导因子.晴天茎流速率的主要影响因子依次为太阳辐射、空气相对湿度和空气温度；阴天依次为太阳辐射和空气温度.蒸腾量日际变化或季节变化特征为4月份逐渐升高、5～6月份达到高峰值、7月份后逐渐降低、10月份达到第二次高峰、11月初迅速降低.主要生长期蒸腾量为708.93 mm,其中,主要需水期(5～7月份、10月份)的蒸腾量为423.41mm,占主要生长季的59.72％.%Stem sap flow dynamics of Fuji'apple trees during the growing season with a year in the southwestern of Shandong province were studied by thermal diffusion probe (TDP) , and total solar radiation, air temperature, air relative humidity and wind speed were measured by automatic weather recording system synchronously. According to the manual records of weather conditions, two most representative weather conditions (sunny and cloudy days) were gathered up to analyze the relationships of sap flow rate with meteorological factors. The results showed that the change of sap flow rate in sunny days was in a form of single - peak curve and in cloudy days was in multi - peak curve. The diurnal variations of sap flow rate and its dominant affecting factors differed with weather conditions, and solar radiation was always the dominant factor affecting stem sap flow rate. The main factors of stem sap flow rate in sunny days were solar radiation, air relative humidity and air temperature, and in cloudy days they were solar radiation and air temperature. The daily variations of transpiration is characterized with that transpiration rose gradually in April, and reach a peak during May and June, fall down readily in July, reach a second peak in October and descend rapidly in November. The transpiration was 708.93mm in the main growing season and the main water requirement period (May, June, July and October) was 423.41 mm among them, accounting for 59.72%.
  • 摘要：Individuals of arthropods in Mixed forest of aspin and birch and Scotch pine forest were significant higher than that in North china larch forest; both common groups and special groups were found in arthropod of 3 forest types by the study of arthropod structure; the arthropod community was shown a situation of vertical layered and significant surface accumulation, the arthropods were decreased as the deep of soil layer in 3 forest types and such a trend was gentler in Scotch pine forest than that in other 2 forest types; temperature and humidity were the most important factors in the soil 0 ~ 10cm underground, both temperature and humidity were shown significant relations to soil arthropod in North china larch forest while the humidity shown a more important im-paction, and the impact factor was very different in the soil 10 ~ 15cm underground of different forest stands.%通过研究发现不同林分类型中,节肢动物在个体数量上,山杨桦木混交林和樟子松林明显高于华北落叶松林；在组成结构上,三种林分类型中不仅具有共有类群,还分别具有特有类群；发现节肢动物具有垂直分层现象,并具明显的表聚性,三种林分类型在不同土壤层次之间均表现出递减的变化,但樟子松林中的变化明显小于其他两种林分；在0～10cm的土壤中,温度和湿度是影响土壤节肢动物的主要因素,其中华北落叶松林中土壤节肢动物的变化与温度和湿度均呈现极显著的正相关关系,其它两种林分中湿度的影响较大,在10～ 15 cm的土壤中,各林分的影响因素差异较大.
  • 摘要：为统一本刊载文格式，参照有关国际和国家标准，特制定本须知，请作者参照撰稿。对不符合以下规定的稿件一律作退稿处理。
  • 摘要：Indoor air pollution will cause a series of adverse effects on human health. Indoor air quality in laboratories will also affect the staffs physical health. This test was up to Determine SO2, NO2, ammonia, formaldehyde, PM10 and the anet then to radon for each environmental lab of Resources and Environment Institute of Shandong Agricultural University, analyse the results and get evaluation. The test results show that all indicators reached the standard except ammonia ; all indicators'concentration difference of each laboratory was non - significant ( P < 0.05 ) , except HCHO; the indoor air quality of every laboratory belongs to slight pollution. The indoor air quality of laboratories is mainly related to the experimental activities and drug - volatile.%室内空气污染会对人类的身体健康造成一系列的不良影响.实验室内空气质量的好坏同样会影响实验人员的身体健康.对山东农业大学实验中心环境实验室进行二氧化硫、二氧化氮、氨、甲醛、可吸入颗粒物及氡的测定,并对测定结果进行统计分析与评价.测定结果显示,各实验室除了氨的含量超标以外,其他各项指标均达标；除了甲醛外,其他各项指标的各实验室浓度差异均未达到显著性水平(P＜0.05)；各实验室室内空气质量均属于轻度污染水平；室内空气质量主要与实验活动及药品、试剂的挥发有关.
  • 摘要：通过一维固结试验分析了各级压力下非饱和重塑土在加水饱和过程中的变形特征,结果显示不同压力下试件饱和过程的变形呈现出不同特征.试验结果如下:50 kPa压力下呈现出膨胀特征；100 kPa、150 kPa和200kPa压力下,呈现出先膨胀后压缩的特征,而且最终变形与加水前相比也各有不同；300kPa和400kPa压力下,试件压缩变形量明显增大.此种变形特征可能会导致土石坝心墙在蓄水过程中形成裂缝,从而为土石坝心墙发生水力劈裂破坏提供条件.%By using the conventional oedometer consolidation test, the deformation characteristics of unsaturated remolded soil under constant compression stresses subjected to wetting process were analyzed. The test result indicates that the deformation characteristics were different under different constant compression stresses. The test result is as follows; under the pressure of 50kPa the specimen was expansive; under the pressure of lOOkPa, 150kPa and 200kPa, the deformations had a transition from expansion to compression, and the final total deformations were respectively different from the deformations compared with prior to the saturation process; and under the pressure of 300kPa and 400kPa, the collapse was observed. The deformation characteristics may lead to cracks in the core of earth - rock fill dam which cause the hydraulic fracture.
  • 摘要：For now, the energy of rural residential districts mainly is non - renewable fossil fuels, but the renewable energy reserves of rural residential districts are very rich, considering the utilization of renewable energy especially biomass energy and replacing non - renewable energy resources to the maximum is very important to a-chieving the twelve - five energy strategy goals of our country. This paper aimed at the existing problems in energy planning and utilization for rural residential districts, discussed the methodologies of energy planning and design based on the ecological cycle theory, and took Ma Jialin village of Shandong for example to explain the specific applications of this method, which aimed at demonstrating the energy planning utilization in rapidly urbanizing regions.%目前村镇住区采用的能源基本上是不可再生的化石能源,而我国村镇地区的可再生能源储备非常丰富,在村镇住区规划中考虑可再生能源尤其是生物质能源的利用,最大限度地替代不可再生能源,对实现我国十二五能源战略目标非常重要.本文针对村镇住区能源规划利用中存在的问题,探讨了基于生态循环理论的村镇住区能源规划设计方法,并以山东省沂水县马家林村为例,说明了该方法的具体应用,以期对快速城市化地区村镇能源的利用起到示范作用.
  • 摘要：本文对DEG/ENaC基因家族的结构特征、功能与成员组成进行了介绍,分别阐述了各亚家族的特点,并列举了PPK基因的国内外最新研究发现.
  • 摘要：为探讨容器大小及不同大小容器间转换对平邑甜茶实生苗木的影响,试验设置了相同土壤质地的不同容积的育苗容器处理.结果显示,不同容积容器对平邑甜茶苗木地上部生长量、根型参数、土壤微生物数量和土壤酶活力产生显著影响.生长前期,T2(中号容器)处理的平邑甜茶苗木地上部生长量、根型参数指标、细菌数量和硝酸还原酶活性均明显高于T1(大号容器)处理和T3(小号容器)处理,真菌数量相反.生长中后期T1处理的苗木地上部生长量、根型各项参数指标和细菌数量均最大,而真菌数量和硝酸还原酶活性呈降低趋势.容器转换结果表明,移栽后栽培基质中细菌数量显著增多,而真菌数量明显减少.T4处理(中号容器中生长的幼苗移栽到大号容器)中期苗木和根系生长量高于T2处理,低于T1处理；生长后期,T4各项参数达到最大.T5处理(小号容器中生长幼苗移栽到中号容器)中期苗木加粗较多,后期加高生长较快.本试验表明,中号容器适合苗木前期生长,移栽至大号容器后苗木生长加快.%To study effects of the different containers sizes and its transition on growth of Malus hupehensis Rend seedlings, containers with different capacity and the same soil medium were used in the experiment.. Results suggested that: different containers had significant effects on growth indexes for seedling, morphological parameters of root, quantity of microorganism and activity of nitrate reductase in soil. At early stage of growing seedlings, Seedings in T2 ( moderate container) treatment possessed the highest amount of growth, morphological parameters of root, quantity of bacteria and activity of nitrate reductase, the quantity of fungus had the opposite trend; at the middle and later stage of growing seedlings, while seedlings in Tl (large container) treatment shown the highest amount of growth of aboveground part and morphological parameters of root of seedlings, quantity of bacteria in soil, both quantity of fungi and activity of nitrate reductase were apparently decreased. The transitional experiment concluded that; the quantity of bacteria apparently increased while the fungus decreased in the soil medium after transition. At the middle stage, the amount of growth of indexes for seeding and morphological parameters of root in T4( seedings transported from the moderate container to the larger container ) treatment is larger than T2 treatment while smaller than Tl treatment. At the later stage, T4 treatment possessed thernhighest amount of growth. Seedings of T5 (seedings transported from the small container to the moderate container) treatment had apparently faste stem diameter growth at the middle stage and stem height growth at the later stage. Hence, growing seedling with moderate container at early stage and then transferring them to larger ones can improve quality of seedlings of Malus hupehensis Rehd.
  • 摘要：In this study, the separation effect of macroporous resin for the purification of ginkgo flavonol aglycone prepared by the enzymatic hydrolysis of the Immobilized B - glucosidase was developed. Based on the results of static adsorption and desorption, adsorption dynamic, YWD07a resin was the best one for the separation and enrichment of flavonol aglycone. The optimal separation conditions were as follow: on adsorption, flavone aglycone concentration of sample solution, pH, flow rate was 3.3 mg/mL, 5.0, 2 bed volume (BV) per hour, respectively. ; on desorption, volume of elution solvent, flow rate, enthaol concentration was 6 BV, 3 BV/h, 70 % (v/v), respectively. Under these conditions, the content of flavone aglycone increased from 18.5% to 80.5% in the crude product, and the recovery of flavone aglycone reached 73.6 %.%以银杏提取物的酶水解液为实验材料,研究大孔吸附树脂分离纯化其中的银杏黄酮苷元的工艺.通过静态吸附-解吸和吸附动力学实验,从3种大孔吸附树脂中筛选出非极性YWD07a为最适合分离纯化银杏黄酮苷元的树脂.YWD07a树脂吸附分离银杏黄酮苷元的最佳工艺条件为:吸附:银杏黄酮苷元的浓度3.26 mg/mL,pH 5.0,流速2 BV/h；解吸:洗脱体积6BV,流速3.0BV/h,乙醇浓度70％.在最优条件下得到的银杏黄酮苷元产品中银杏黄酮苷元含量由18.5％提高到80.5％,回收率为73.6％.
  • 摘要：一串红以其生长快、株型饱满、适应性强、花期长、花色艳丽等特点,成为园林中最为普遍栽培的草本花卉.近年来无土轻质栽培基质的使用越来越受到重视.本文以一串红品种‘展望深紫’和‘一串白粉’为试材,研究了不同氮素施用量对温室珍珠岩栽培的一串红营养生长的影响.结果表明:当供氮浓度低于25 mg·L-1时,两个品种表现出典型的缺氮症状:植株叶片发黄且停止生长；当供氮浓度在200 mg·L-1时,一串红株高、冠幅、叶绿素含量及干物质重各项指标均达到最大值.而高品质的一串红要求株型饱满,因此当供氮浓度在150 mg·L-1时,一串红观赏价值最高.当供氮浓度大于200 mg·L-1时,两个品种植株的地上部和地下部生长均受到不同程度的抑制,表现出氮过量症状.%Because of its fast -growing, plump plant -type, strong adaptability, long flowering period, brightly colored, Salvia splendeas become the most widely cultivated herbaceous flowers in the garden. In recent years, soilless culture substrates has been generally accepted. Different nitrogen fertilizer affect the vegetative growth of soilless culture of Salvia splendens. Vista Shenzi'and Salvia splendens. Yichuan Baifen' in the greenhouse. Results show that: For nitrogen concentrations of less than 25 mg L-1, the two species showed the typical symptoms of nitrogen deficiency: leaves become yellow and plant stop growing, for the nitrogen concentration of 200 mg L-1, the plant height, crown width, chlorophyll content and dry matter weight of Salvia splendens have reached the maximum. The requirements of high - quality Salvia splendens is plump plant - type, so when the nitrogen concentration of 150 mg L-1 was applied, itproduces the highest ornamental value. For nitrogen concentration greater than 200 mg L-1, the above - ground part and the under -ground part of two species were inhibited , and show Symptoms of nitrogen excess.
  • 摘要：针叶小爪螨是我国南方用材树种杉木和北方经济林树种板栗上的重要害螨,为了解该螨不同种群间的遗传分化情况,采用垂直板型聚丙烯酰胺凝胶电泳技术对其雌成螨的醑酶同工酶进行了比较研究.结果表明:所有阔叶树种群的酶谱特征完全一致,未产生分化；2个针叶树种群(浙江杉木种群、吉林云杉种群)间以及针叶树种群与阔叶树间产生了明显的分化.%The spruce spider mite, Oligonychus ununguis (Jacobi) (Acari; Tetranychidae), is the main pest mite of Chinese fir, Cunninghamia lanceolata, and chestnut, Castanea mollissima. Chinese fir is the timber tree species in southern China and chestnut is the economic tree species in northern China. Esterase isozymes in a-dult females from different populations of Oligonychus ununguis were studied by means of non - denaturing poly-acrylamide vertical slab gel electrophoresis for the purpose of understanding the genetic differentiations between different populations. Results showed that the electrophoretogram of esterase isozymes of all the deciduous populations was same and no differentiation existed between different deciduous populations. There were significant differentiations between coniferous populations and deciduous populations. Significant differentiations were also found between two coniferous populations, fir population from Zhejiang Province and spruce population from Jilin Province.
  • 摘要：The study on the in vitro antioxidant activity of garlic green pigments was conducted with four different in vitro antioxidant models, they were hydroxyl radical system, superoxide anion system, DPPH system and ABTS system. The results showed that the pigments presented antioxidant activity on all of the four radicals. As the concentration of garlic green pigments raised, the rate of radical scavenging increased significantly. The ability of garlic green pigments on scavenging free radical were ranked as follows: hydroxyl radicals > superoxide anion radicals > ABTS radicals > DPPH radicals.%本试验采用了羟自由基体系、超氧阴离子体系、ABTS体系和DPPH体系4种不同的体外抗氧化模型进行大蒜绿色素体外抗氧化活性研究,结果表明,大蒜绿色素对羟自由基(·OH)、超氧阴离子(O2-·)、ABTS自由基、DPPH自由基均表现出抗氧化活性,且随着大蒜绿色素浓度增加,自由基清除率显著增加.大蒜绿色素清除自由基的能力顺序为:羟自由基＞超氧阴离子＞ ABTS自由基＞DPPH自由基.
  • 摘要：无喉道量水槽以其测量准确、结构简单易于建造、造价低等特点,在灌区测水量水中得到广泛应用.本文对无喉道量水槽结构形式、量水水力学原理、流量计算方法以及实时遥测所需要的水位传感器、通信设备、工控机和组态软件等进行了阐述,并结合工程实际对量水精度和系统稳定性进行了研究.%A cutthroat flume is commonly used as flow measuring device in irrigation district due to its accurate measurement,simple structure and low cost. In this paper, the structure, hydraulic principle, discharge calculation method of cutthroat flume and water level sensor, communication equipment, industrial computer and configuration software in real - time discharge telemetry system are described. Also, a study was performed to examine the accuracy of discharge measurements and the stability of the system in the practical application.
  • 摘要：After the transformation of the Nansi lake of two - dam water conservancy hub, the weir gate discharge conditions changed. According to hydrological specification, the use of acoustic doppler flow meter (of ADCP) to collect information on existing vent flow. Deriving curve analysis verification. Measured data show that the discharge curve is no longer applicable after the transformation of engineering flow conditions. Preliminary analysis of the part of the flow pattern coefficient curve in line with the conditions of weir gate law and the two - dam. It is recommended according to the status of conditions in the governance of the engineered to carry out a two - dam discharge curve and lakes flood research to provide accurate and reliable technical basis for flood control and South flood resource use planning.%南四湖二级坝水利枢纽改造后,堰闸泄流条件发生变化,根据水文规范,利用声学多普勒流量仪(ADCP)收集资料,对现有泄流量推求曲线进行了分析验证.通过实测资料分析表明,泄流曲线已不适用改造后的工程出流条件,初步分析的部分流态系数曲线符合堰闸规律和二级坝工况实际.提出根据工程改造治理后的现状条件,开展二级坝泄流曲线以及湖区行洪研究的建议,为防汛调度、南水北调洪水资源利用提供准确可靠的技术支撑.
  • 摘要：人工蜂群算法是一种模拟蜜蜂觅食行为的人工智能优化算法.作业调度问题是指在一个系统内通过某种方式分配工作以达到工作效率或资源分配最优.在本文中,将遗传算法的变异和杂交操作插到传统的人工蜂群算法中,从而提出一种改进的人工蜂群算法.变异操作在雇用蜂阶段后插入,杂交操作在跟随蜂阶段之后插入.实验表明,本文的改进人工蜂群算法在作业调度中的作用是有效的、显著的.%Artificial Bee Colony Algorithm (ABC) is an optimization algorithm based on the ntelligent foraging behavior of honey bee swarm. The job scheduling wovk is the problem of assigning the jobs in the system in a manner that will optimize the overall performance of the application. In this paper, An Efficient artificial bee colony ( ABC) algorithm, where the additional mutation and crossover operator of Genetic algorithm ( CA) weve used in the classical ABC algorithm. The crossover operator after the employed bee phase and mutation operator after onlooker bee phase of ABC algorithm hawe been used. The simulated results show that ABC proves to be a better algorithm when applied to job scheduling problem.
  • 摘要：多环芳烃(PAHs)是农业土壤中较常见的一类重要有机污染物,其污染具有持久的致癌、致畸、致突变效应.本文着重介绍了农业土壤中PAHs的分析方法和降解方法,并对土壤中PAHs的污染现状、来源及其对农作物的影响等进行了回顾和综述.目前研究表明:我国农业土壤已普遍受PAHs污染,并且部分地区已经处于中等甚至严重污染水平,生态风险极高；污染来源复杂,但人为源,如煤、石油等有机物的不完全燃烧是环境中PAHs的主要来源；高浓度的PAHs会影响作物的生长,甚至直接导致植物死亡.
  • 摘要：本论文对生防枯草芽孢杆菌B579补料分批发酵工艺进行了优化,提高了菌体浓度和最终芽孢浓度,为生防菌剂的大规模生产奠定了基础.为获得较高的最终芽孢浓度,分别优化了葡萄糖补加时机、浓度控制范围以及发酵过程pH.利用7L发酵罐,当葡萄糖浓度降至3.0g/L时开始连续补加葡萄糖至3.0-6.0 g/L,发酵过程控制pH为7.0,培养24h菌体浓度达到3.9×1010CFU/mL,继续培养至40h芽孢浓度达到2.8×1010 CFU/mL,分别是分批发酵的7.5倍和7倍.发酵过程葡萄糖浓度对菌体生长和芽孢形成有较大影响,过高的葡萄糖浓度会抑制芽孢的生成,发酵过程控制合适的葡萄糖浓度有利于菌体浓度和芽孢浓度的提高.%In this research, the cell concentration and the final spore concentration were improved by optimizing the fed - batch fermentation process of biocontrol Bacillus subtilis B579, and this study provide the basis for biopesticide production in large scale. For obtaining a higher concentration of spores, the glucose - feed time, controlled glucose concentration and pH of medium was optimized, respectively. In a 7 L fermenter, the glucose was supplemented when its concentration was below 3. 0 g/L and was controlled between 3.0 - 6.0 g/L. The fermentation pH was controlled as 7.0. In this condition, the cell concentration was 3.9 1010CFU/mL after 24 h cultivation and the spore concentration of 2. 8 1010CFU/mL was achieved after 40 h cultivation, respectively, which represent a 7.5 -fold and 7 —fold increasement compared with those of batch fermentation. Glucose concentration showed a significant effect on cell growth and sporulation. It is important to control glucose -concentration for improving cell growth and the final spore concentration, because high concentration of glucose will inhibit the sporulation B. subtilis.
  • 摘要：By using method method of modified whole root research, the study was conducted to discuss the spatial distribution of root system of 3a,6a,9a the three stand age of P. deltoites cv. Zhonghe - lin the Yellow River alluvial plain, and analyze root biomass, root length, length density, surface area and volume of fine root ≤2 mm in diameter. Results showed that, in vertical direction, the root biomass, root length, length density, surface area and volume of roots ≤ 2 mm in diameter in every stand age of poplar plantation in general is gradually increased with soil depth decreases, and there are a significant differences between different stand age and different soil layer. Fine roots are distributed evenly in the horizontal, but between stand age and between different distances from the trunk still showed obvious difference. The space distribution of fine roots in Poplar plantation provides the basis for woodland soil improvement and fertilizer.%采用改良全根调查方法,于生长季节末期对黄河冲积平原3a、6a、9a三个林龄的中菏1号杨树(Populus deltoites cv.‘Zhonghe-1’)人工林根系空间分布特征进行了调查,并对直径小于2 mm的细根生物量、比根长、根长密度、表面积、体积进行测定分析.结果表明:在垂直方向上,各林龄杨树人工林细根生物量、根长密度、根尖数、细根表面积、细根体积总体上随土壤深度增加而逐渐减小,林龄之间、土层之间差异明显.细根在水平方向上的分布较为均匀,但林龄之间、以及距树干不同距离仍表现出明显差异.杨树人工林细根空间分布规律为林地土壤改良和培肥提供了依据.
  • 摘要：2009-2011年连续3年,对不同玉米播期的灰飞虱发生情况、玉米粗缩病发病情况及玉米产量进行了系统调查.结果表明:从4月25日至6月19日每隔5d,连续12次播期的试验区,3年灰飞虱成虫种群的消长动态基本相同,在6月14日达到高峰；4月30日之前和6月19日以后播种,粗缩病发病率明显降低,灰飞虱发生高峰期前播种发病率最高,不适于播种,且在5月20日至5月30日播种玉米产量损失最大.因此,播期是影响玉米粗缩病发生的重要影响因素,适当早播和晚播,避免玉米苗期与一代灰飞虱成虫发生高峰期相遇,可预防玉米粗缩病的爆发.%From 2009 to 2011, the occurrence of L. striatellus and maize rough dwarf disease incidence and corn production of different corn sowing period was systematic investigation. The results showed that during 3 years the population dynamics of Laodelphgax striatellus adult was essentially the same from April 25 th to June 19 , reaching a peach at June 14th. Before April 30th and after June 19th, the incidence of the maize rough dwarf disease was significantly reduced. The morbidity of maize rough dwarf disease sowing during incident peak of small brown planthopper was the highest, and the losses of com yield seeding from May 20th to May 30th was the greatest. Therefore, the important factors affecting the occurrence of maize rough dwarf disease is sowing date. It is effective to avoid the peak of mass poisoning meet planthopper by appropriate early sowing or late sowing which can prevent the outbreak of maize rough dwarf disease.
  • 摘要：Traction performance is the main index of tractor. This paper takes a four - wheel - drive tractor as object, after theoretical calculation using MATLAB, the function and usage of the simulation software - CRUISE is analyzed, then the simulation model is built and studied. The accuracy of the models can be got from the exactly similar results. Building a vehicle system model using this software is not only convenient and simple but also direct - viewing and easy to debugging. With this software, much time is saved and it is easy for users to analyze and study the parameters' influence to vehicle performance so that system design and optimization can be achieved fleetly.%牵引性能是拖拉机的一项重要性能指标.文章以某四轮驱动拖拉机为研究对象,在MATLAB理论计算基础上,分析CRUISE仿真软件功能与使用方法并进行了建模仿真分析.两种软件仿真的结果基本一致,可在一定程度上说明模型的正确性.应用CRUISE软件建立车辆系统模型具有方便、简单、容易调试、直观性强等特点,不仅可以节省大量时间,而且便于用户分析和研究各参数对车辆性能的影响,快速完成系统的设计与优化.
  • 摘要：Financial appraisal on limited company is an important part of financial management. This paper compared the characteristics among Du Pont analysis, Balance score card, Economic value added and Factor analysis, and screened out Factor analysis and used it to analyze on the financial performance in Haier Co. Ltd with SPSS16.0 software and calculated its dynamic change from 2001 to 2010 years. It will be important sense for summing the company financial progress status, guiding the consumer investment and predicting the development trend of limited company in the future.%财务绩效评价是上市公司财务管理的重要内容之一.本文通过比较杜邦分析法、平衡计分卡法、EVA经济增加值法和因子分析法的特点,筛选出因子分析法并利用SPSS16.0软件,对其青岛海尔集团公司2001～2010年的财务绩效指标进行实证分析,计算出该公司十年来财务绩效的动态变化,对于总结公司的财务发展状况,引导消费者投资和预测企业未来发展趋势具有重要的指导意义.
  • 摘要：随着经济的迅猛发展和人们对电动车的需求,铅蓄电池生产企业越来越多.铅蓄电池的生产可能造成周围土壤的重金属污染.土壤受重金属污染后,不仅会退化土壤肥力,使农作物产量下降,而且可能通过食物链的传递危害人类健康.因此,土壤重金属污染问题受到越来越多的重视.泰安市世华电缆电池有限公司以生产铅酸蓄电池及零部件为主,为了解世华电缆电池有限公司周围土壤重金属污染情况,以该公司周围一定距离土壤样品为研究对象[1],在野外采样和实验室分析的基础上,评价企业周围土壤受Cu、Zn、Pb三种重金属的污染程度.结果表明,该公司周围环境中部分土壤样品中Cu、Zn、Pb含量与土壤环境背景值相比有显著提高(p＜0.05),但周边土壤中三种主要重金属的污染均未超过国家土壤环境质量二级标准,污染等级为清洁,公司对周围土壤重金属污染影响较小.
  • 摘要：中国有着丰富的湿地资源,如何以保护为前提,对湿地资源进行科学的开发利用,是维护湿地生态系统正常运转的关键性问题.本文着重研究镇江焦北滩东大堤以东的618hm2土地.通过进行实地考察,在当地政府部门的协助下,搜集了植被、水资源、湿地退化情况等相关资料,运用因子加权评分法对其进行生态适宜性分析,并绘制了生态适宜性分区图.在理论分析的基础上,文章指出用生态规划方法指导湿地公园建设,可以很好的协调生态效益和经济效益.最后,文章分别通过保护性规划和利用性规划为湿地公园建设提出指导性建议.
  • 摘要：多层复合地基沉降量计算,对复合地基压缩模量的处理是关键问题.分析了先水平后垂直、先垂直后水平、《建筑地基处理设计规范》等方法的计算原理、计算方法的优缺点.理论和算例分析表明,先水平后垂直、先垂直后水平两种方法计算地基沉降量是等效的.先垂直后水平将地基简化为单一均质体,计算简单方便,建议采用第二种方法计算地基沉降量.
  • 摘要：本文提出了一种基于信息增益改进的信息增益特征选择选择方法.首先对数据集按类进行特征选择,减少数据集不平衡性对特征选取的影响.其次运用特征出现概率计算信息增益权值,降低低频词对特征选择的干扰.最后使用离散度分析特征在每类中的信息增益值,过滤掉高频词中的相对冗余特征,并对选取的特征应用信息增益差值做进一步细化,获取均匀精确的特征子集.通过对照不同算法的测评函数值,表明本文选取的特征子集具有更好的分类能力.
  • 摘要：介绍“新中式”建筑风格的形成及演变发展过程,剖析其风格特征,阐明了“新中式”建筑风格是引导我们去追寻传统文化,去创新具有中国特色的建筑风格,走具有中国特色的城市建筑发展之路.
  • 摘要：本文提出了一种利用三维激光扫描系统测量立木材积并建立材积回归模型的方法.该方法是在北京鹫峰森林公园林场,利用三维扫描系统在样地内对油松、龙爪槐、银杏三种树种,共180株标准木进行立木三维扫描,可以获取精确的立木的胸径、树高、冠幅等基本测树因子,并根据点云数据构建树木模型,实现树干的三维表面重建,得到精确单木材积.然后由这些精确的单木材积数据回归建立一元立木材积模型、二元立木材积模型.通过内、外符合精度检验之后,最终所得模型所描绘的曲线与三维激光扫描所得构建的材积曲线基本上是一致,说明这种方法能够用于回归建立立木材积模型及材积表.这种方法工作效率高、不破坏树木,能够用于推广回归建立立木材积模型及材积表,对于建立新型材积模型有普遍意义.

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