桑盾蚧雌介壳在桃园中的空间分布特征研究

１９９２～１９９３年对桑盾蚧（Ｐｓｅｕｄａｕｌａｃａｓｐｉｓｐｅｎｔａｇｏｎａ）雌介壳在５ａ～８ａ生桃树上的分布进行了研究。结果表明：桑盾蚧雌介壳在桃树不同方位枝条上所占树表皮面积和枝条受害程度均表现为南边＞东边＞西边＞北边，且雌介壳多集中于主枝上；主枝上空介壳多于小枝；在桃园中雌介壳呈聚集分布。     

欧洲水仙鳞片组织培养与快速繁殖

以欧洲水仙‘Dutch Master’为研究材料,通过对鳞片取材部位、培养光照、激素配比以及组培苗移栽基质的研究发现,欧洲水仙初代培养的较适外植体为内层鳞片下部,合适光照度为1 000 lx。愈伤组织诱导培养基为MS+6-BA 2.0 mg/L+2,4-D 0.3 mg/L+蔗糖30 g/L,小鳞茎的诱导分化培养基为MS+6-BA 2.0 mg/L+NAA 0.2mg/L+蔗糖30 g/L,小鳞茎继代增殖培养基为MS+6-BA 1.5 mg/L+NAA 0.3 mg/L+蔗糖30 g/L,生根培养基为1/2MS+6-BA 0.3 mg/L+NAA 0.5 mg/L+蔗糖20 g/L。炼苗移栽基质配比为V(蛭石)∶V(泥炭土)∶V(园土)=1∶1∶2。     

重新构建乡村林场产权制度的研究

浙江省乡村林场近几年有了迅速发展，但同时其产权制度建设是严重滞后和欠缺的。文章认为重新构建乡村场产权制度是适应社会主义市场经济发展，建立现代林业企业制度的客观要求的。是深化南方集体林区林业改革，推行林业股份合作制的前提条件，是发展规模经济的需要。根据不同类型乡村林场产权制度建设的调查研究。文章提出理顺产权关系，明晰产权主体，改革现行产权结构和切实保护产权主体利益等具体措施，以促进乡村林场的健康发展     

普通高校女大学生初学健美操应注意问题的分析与探讨

当今,我国高校体育教学不断深入改革与创新,大学体育课不断的完善,健美操已成为当今女大学生的一种时尚运动,在校园内很受欢迎。对普通高校女大学生在初学健美操阶段应注意的问题进行了分析探讨,并提出了相应的建议。     

黑背唇瓢虫雌雄成虫的活体无损伤鉴别方法

为了对黑背唇瓢虫Chilocorus melas Weise成虫进行活体无损伤鉴别,通过在解剖镜下反复对比,发现雌雄黑背唇瓢虫成虫存在3处可在放大镜下观察到的不同特征,通过这3处不同特征,几乎不伤害虫体就能迅速、准确地鉴定该瓢虫的雌雄性别,为下一步研究其室内饲养技术研究提供参考。     

拖拉机动量飞轮主动防侧翻控制与模型试验研究

针对拖拉机侧翻致死致伤事故仍时有发生的问题,基于旋转刚体加速时的反向施矩原理,以反作用动量飞轮为执行元件,提出了从主动安全角度解决拖拉机侧翻问题的研究方法。通过构建拖拉机动力学系统数学模型,解析了整机侧翻行为的动态演变机理。为保证拖拉机主体结构的完整性,将动量飞轮置于拖拉机前部,取代传统静态配重的同时可主动提供防侧翻力矩。应用Matlab/Simulink软件,对反作用飞轮的回稳过程进行了基于PID控制的有效性仿真分析,同时设计并搭建了比例模型试验平台,对主动施矩飞轮的回稳控制效果进行了试验验证。结果表明,装备飞轮的拖拉机与无控制组对比,在一次试验中可多次实现整机的防侧翻控制,使整机防侧翻性能得到明显改善,且不同行驶工况下的试验数据与仿真结果的相关性较强,充分验证了本文拖拉机侧翻动力学模型的有效性。     

Index-based assessment of agricultural drought in a semi-arid region of Inner Mongolia, China

Agricultural drought is a type of natural disaster that seriously impacts food security.Because the relationships among short-term rainfall,soil moisture,and crop growth are complex,accurate identification of a drought situation is difficult.In this study,using a conceptual model based on the relationship between water deficit and crop yield reduction,we evaluated the drought process in a typical rainfed agricultural region,Hailar county in Inner Mongolia autonomous region,China.To quantify drought,we used the precipitation-based Standardized Precipitation Index(SPI),the soil moisture-based Crop Moisture Index(CMI),as well as the Normalized Difference Vegetation Index(NDVI).Correlation analysis was conducted to examine the relationships between dekad-scale drought indices during the growing season(May–September)and final yield,according to data collection from 2000 to 2010.The results show that crop yield has positive relationships with CMI from mid-June to mid-July and with the NDVI anomaly throughout July,but no correlation with SPI.Further analysis of the relationship between the two drought indices shows that the NDVI anomaly responds to CMI with a lag of 1 dekad,particularly in July.To examine the feasibility of employing these indices for monitoring the drought process at a dekad time scale,a detailed drought assessment was carried out for selected drought years.The results confirm that the soil moisture-based vegetation indices in the late vegetative to early reproductive growth stages can be used to detect agricultural drought in the study area.Therefore,the framework of the conceptual model developed for drought monitoring can be employed to support drought mitigation in the rainfed agricultural region of Northern China.     

剩余活性污泥生物吸附重金属的动态试验

用模拟污水在自制的活性污泥系统装置中进行不同投配比的回流剩余活性污泥（WAS）至初沉池的动态小试，当污泥的投配比为0.030g/L时，污水中Cu,Zn,Ni3种金属离子在初沉池分别可获得59%，39%和20%的去除率，总系统对污水中Cu,Zn,Ni的去除率比没有WAS回流时分别提高了23%。17%和11%，另外，回流WAS系统也改善了系统对污水中CODcr的去除率，试验结果表明将部分WAS回流至初沉池吸附去除重金属是可行和有效的。     

烤烟种植规模与经济性状的关系分析——以江西崇仁为例

为给崇仁县烟农适度种植规模提供理论参考,对崇仁县2013年烟农的种植规模和烤后烟叶经济性状进行描述统计、相关分析和聚类分析。结果表明:种植规模和经济性状在烟农之间存在着广泛的变异。单户烟农种植规模与上等烟比例呈显著正相关,与中等烟比例之间呈显著负相关,与单位面积产值、单位面积产量之间存在显著正相关,和均价呈正相关。在崇仁县现阶段的生产水平下,烟农种植规模集中在2.334~2.413 hm 2范围内,烟农的种烟综合经济效益较高。     

Genetic structuring and diversity patterns along rivers – local invasion history of Ambrosia artemisiifolia (Asteraceae) along the Danube River in Vienna (Austria) shows non‐linear pattern

Ambrosia artemisiifolia is an annual weed from North America that nowadays is invasive in many countries worldwide. In Austria, numerous populations of A. artemisiifolia are located along the Danube River, especially along the ‘New Danube’ (Vienna). This area is characterised by ruderal and riparian sites, which are regularly flooded. To better understand the spread of A. artemisiifolia and its colonising behaviour along the Danube River, we analysed genetic structure and diversity based on 23 populations linearly arranged along the Viennese Danube riverbed and upstream, utilising the Amplified Fragment Length Polymorphism (AFLP) fingerprint method. We generated 284 polymorphic AFLP markers across 446 A. artemisiifolia plants. The genetic diversity within populations was higher (HW = 0.091) than among populations (HB = 0.007). This result indicates A. artemisiifolia introductions from similar mixtures of sources or spread from a single already mixed introduction. Within our local setting, we were unable to identify neither source or sink populations nor an obvious linear genetic structuring. Genetic among‐population differentiation was low to moderate (amova ‐derived F_ST = 0.124). Lack of geographical structuring is indicative of highly dynamic gene flow, which is further supported by the absence of an isolation‐by‐distance pattern. Multiple introductions and non‐directional gene flow are most likely promoted by anthropogenic disturbance and human‐mediated dispersal. Our results demonstrate the ability and speed of A. artemisiifolia to settle in newly disturbed areas and the difficulties to predict invasion directions, as downstream river dispersal was negligible.