Design and Implementation of Individual Tree Growth Visualization System of Cunninghamia lanceolata

Nonlinear mixed effects model(NLMEM) is built on the relationship of the fixed and random effects in the regression function.The NLMEM has an obvious comparative advantage in analyzing the longitudinal data,repeated measures data and multilevel data.Two-level NLMEM is used to analyze the dominant height for Chinese fir (Cunninghamia lanceolata).The authors outline the two-level NLMEM and introduce the parameters estimation method of the model.Based on five common Richard and Logistic models,the mixed model is built.The modeling data are used to calculate and compare with 19 models derived from each based model,and 5 optimal mixed models are built.Compared the 5 optimal mixed models with traditional regression models,it is showed that the two-level NLMEM has a better fitting effect than the regression model.     

极早熟辣椒新品种湘椒64号的选育

湘椒64号是由伏地尖辣椒经多年提纯复壮和定向选择而成的衡阳地方特色优良品种.该品种熟性极早,始花节位7～8节,果实羊角形,商品成熟果绿色,生理成熟果颜色鲜红,果长13～15 cm,果宽约2.2cm,平均单果质量15.5 g,果表光滑,辣味中等,风味好;前期产量为930 kg/667 m2左右,总产量1780 kg/66...     

BIOLOG在土壤微生物群落功能多样性研究中的应用

微生物功能多样性信息对于明确不同环境中微生物群落的作用具有重要意义 ,而微生物群落的定量描述一直是微生物学家面临的最艰巨的任务之一。目前 ,以群落水平碳源利用类型为基础的BIOLOG氧化还原技术为研究土壤微生物群落功能多样性提供了一种简单、快速的方法 ,并得以广泛应用。但它仍然是一种以培养为基础的方法 ,显示的代谢多样性类型也不一定反映整个土壤微生物群落的功能多样性。因此 ,这种方法优点明显 ,缺陷也存在 ,并且在应用过程中还有很多关键的操作要点与技巧。本文综述了BIOLOG研究土壤微生物群落功能多样性的原理、BIOLOG研究土壤微生物群落功能多样性的方法与技巧、应用过程中容易产生的问题及可能克服的办法 ,同时还提出了值得进一步研究的问题。旨在促进对BIOLOG测定土壤微生物群落功能多样性的了解 ,为正确运用这种方法开展土壤微生物群落功能多样性研究提供科学依据和理论指导。     

PAC与PAM复合絮凝剂处理泡菜废水

采用絮凝法对泡菜废水进行了试验,分别考察了絮凝剂的种类、助凝剂的种类、PAM分子量、投加方式、pH值、温度、搅拌转速等条件对泡菜废水絮凝处理效果的影响,为泡菜废水的后期生化处理提供了帮助的同时也可为泡菜厂实际絮凝处理提供一定的参考。在含大量NaCl的泡菜废水中,利用PAM网捕、架桥功能完善了PAC单独作用下絮体细小松散的缺陷,改善了絮凝和沉降性能。研究结果表明：PAC用量150 mg/L,PAM用量25 mg/L,pH6,温度30 ℃,250 r/min快搅2 min,90 r/min慢搅2 min,静置30 min后泡菜废水COD、浊度去除率分别达到了37.7%、96.7%。     

Soil enzyme activities and abundance of microbial functional genes involved in nitrogen transformations in an organic farming system

Organic farming systems receive organic amendments to maintain soil fertility and supply nutrients for plant growth. This study investigated the effect of organic fertilizers (no amendment as control, compost, and manure), and their interaction with cover crops (millet, buckwheat, and black turtle bean) on soil enzyme activities, N transformation rates, and functional gene abundances under an organic production system. Organic N fertilizers had a stronger effect than cover crop type on soil function and functional gene abundances. Soil enzyme activities were increased by both compost and manure, but there were few differences between these treatments. Nitrification potential, nitrite oxidation potential, and denitrification potential were significantly higher in manure-treated than in control and compost-treated soils, indicating application of manure had a higher N loss potential than compost application in this organic farming system. Organic N fertilizers significantly increased the abundance of some genes involved in N mineralization, ammonification, and nitrification (sub, ureC, bacterial amoA and nxrB). The activity of ammonia-oxidizing bacteria and archaea were both increased by organic N fertilizers, and their activities were higher in manure-treated than in compost-treated soils. Overall, the abundance of functional genes was significantly correlated with their corresponding enzyme activity. However, functional gene abundance was less important than soil chemical and microbiological properties in explaining the variation in the corresponding enzyme activity.     

陕北苹果产业集群的问题及对策

基于“钻石理论”,对陕北果业集群进行深入分析和重新定位,从而找出应对金融危机之策。通过产业集群的创新活动,促使产业集群竞争优势中淡化、衰退的因素逐步被新的优势竞争因素取代是产业持续发展的动力。通过陕北果业集群的创新,协调集群内部各环节的发展,保持持续的竞争优势是陕北果业集群健康发展的关键。     

刚性衬砌渠道受冻胀时衬砌层受力的试验研究

为了研究刚性衬砌道受冻胀时衬砌层的受力状况，通过模型模拟试验研究，找出了刚性砌渠道受冻胀时边坡衬砌层（板）的受力情况与其下渠床上含水量渠道横断面高度分布之间的内在规律，为寒区刚性衬砌渠道如何采取防洪胀措施提供了科学依据。     

模拟酸雨对砖红壤盐基离子迁移和释放的影响

对发育于玄武岩的砖红壤进行了室内模拟酸雨淋溶试验,结果表明：（1）酸雨淋溶土壤会引起土壤盐基离子的大量淋失。以土壤中的K＋最易于淋失,Ca^2＋、Mg^2＋的淋失量最大。酸雨pH愈低,Ca^2＋、Mg^2＋、K^＋的迁移量愈大。酸雨淋溶土壤的时间越长,盐基离子的迁移量越大。（2）土壤经≥5d的酸雨淋溶后,土壤交换性盐基离子的含量均随淋溶时间的增加而减少。酸雨的pH不同,则土壤交换性盐基离子所受的影响不同。（3）与原土壤相比较,短期（≤5d）的酸雨淋溶,可使土壤交换性Ca^2＋、K^＋以及强酸性（pH≤3.0）酸雨淋溶的交换性Mg^2＋增加;土壤被酸雨较长时间（≥10d）淋溶后,则会降低土壤交换性Ca^2＋、Mg^2＋、K^＋的含量;不同时间的酸雨淋溶,均会降低土壤交换性Na^＋的含量。（4）土壤经酸雨淋溶后,某些矿物会发生风化,释放出盐基离子,也会使部分交换性盐基离子转成非交换态。     

中国乳业行业及区域增长实征分析

我国乳品加工业发展十分迅速,也取得了显著效益,但其仍存在许多问题,因此对我国乳品加工业及其区域发展特征进行分析研究很有必要。该文基于全国乳品工业1998～2005年年度统计数据以及各省市的综列数据,通过对生产函数的估计以及对影响行业绩效的相关因素的分析,考察了我国乳品行业发展的特点及其区域特征。分析结果显示,我国乳品工业具有明显的规模报酬递增的特点,行业集中和产业结构优化对提高行业绩效具有显著的推动作用。在行业增长的影响因素中,知识进步的贡献率起着举足轻重的作用。     

南水北调工程植被建设的基本理念

 为解决南水北调工程植被建设的基本理念问题,以“人与自然和谐共处”“建设与保护并重”理论为指导,在分析“三纵四横”的南水北调工程具有跨越不同气候带、区域广袤、地域多变的特殊性,并总结前人类似区域研究的基础上,通过分析工程各线路的自然条件和社会经济条件,提出工程植被建设既要有总体的指导思想,又要体现分区的地域特点的理念,从而实现应有的生态效益、经济效益和社会效益,确保长期发挥效能。