基于能值理论的艾比湖地区生态足迹分析

在传统生态足迹模型的基础之上,采用基于能值理论的生态足迹方法计算了博州的生态足迹和生态承载力,并衡量了研究区的可持续发展状况。能值生态足迹方法采用了能值转换率、能值密度等较为稳定的参数,将人类对各种资源的利用转换为太阳能值进行比较,更能真实的反映研究区域的特征。使用能值生态足迹方法计算得到,研究区2007年的人均生态足迹为6.948hm2,人均生态承载力为0.837hm2,人均生态赤字为6.111hm2。与传统生态足迹方法计算结果一致,研究区处于不可持续状态。     

石河子绿洲农业生态经济系统结构与功能分析

从石河子绿洲农业生态经济系统的水土资源、农业种群、产业结构方面以及物质流、能量流、价值流功能进行综合分析,对于建立良好的生态结构及充分发挥农业生态系统功能提出对策.     

应用草坪生态系统于城市生态建设的思考

通过对作为生态城市的重要子系统--草坪生态系统的含义及其生态效益的认识,提出一些有利城市生态建设的种草新模式,并对应用草坪生态系统于城市生态建设过程中存在的一些问题进行探讨.     

畜牧领域专业学位研究生“双导师三段制”培养模式探索与思考:以兰州大学为例

畜牧领域专业学位研究生是为畜牧业输送人才的重要途径,进一步完善该领域研究生的培养模式对满足产业人才需求和研究生的职业选择具有重要意义。现行的畜牧领域专业研究生培养过程存在培养方式和产业需求不太匹配、导师队伍实践能力弱和“双导师三段制”培养模式缺少标准等问题。本文从提升导师专业实践能力、系统设计“双导师三段制”培养模式和培养研究生创新创业能力等角度探索和尝试,为提升畜牧领域专业学位研究生理论、实践和创新创业能力提供参考。     

苹果根系构型及其调控研究进展

 根系是果树栽培管理的基础和中心。重点介绍了苹果根系研究试材的选择、苹果根系构型的类型以及环境营养、土壤条件、栽培容器和生长调节剂等对苹果根系形态构型的影响和调控等方面的研究进展,并提出了进一步研究的内容。     

早熟、优质、抗病甜椒三系杂交种沈研15号的选育

沈研15号是以细胞质雄性不育系A02-7为母本,以恢复系0840-7做父本配制而成的三系甜椒杂交种。该品种早熟,果实方灯笼形,果面光滑,味甜。辽宁省辣椒区域试验平均总产量3710.4kg,平均增产11.0%;国家辣椒区域试验2a平均总产量2753.5kg/667m~2,比对照冀研6号平均增产2.8%。沈研15号适应早春大棚、秋延迟、越冬温室等多种栽培方式。     

文冠果体细胞胚胎发生体系建立

以文冠果果实的幼果期、中期和成熟期种胚为外植体,利用组织培养技术,对影响文冠果体细胞胚胎发生多种培养因子进行筛选,建立稳定的文冠果体细胞胚胎发生的培养体系。结果表明:文冠果果实发育中期的种胚诱导体细胞胚效果较好,种胚在MS+BA 1.0 mg/L+2,4-D 1.0 mg/L+2%蔗糖的固体培养基上暗培养形成愈伤组织,在MS+BA 2.0 mg/L+NAA0.05 mg/L+2%蔗糖的固体培养基上暗培养产生体细胞胚。     

Plasma renin activity and plasma concentrations of aldosterone, cortisol, adrenocorticotropic hormone, and alpha-melanocyte-stimulating hormone in healthy cats

A pathogenetic role of the renin-angiotensin-aldosterone system has been implicated in cats in both systemic arterial hypertension and hypokalemic myopathy. Yet, measurement of plasma aldosterone concentrations (PACs) and plasma renin activity (PRA) has not unequivocally pointed to hyperaldosteronism as a cause of these conditions. To obtain appropriate reference ranges, this study included a large number (130) of healthy house cats of different breeds without a history of recent illness and plasma concentrations of urea and creatinine below the upper limit of the respective reference ranges. In addition, the pituitary-adrenocortical axis was studied by measuring plasma concentrations of adrenocorticotropic hormone (ACTH), alpha-melanocyte-stimulating hormone (alpha-MSH), and cortisol. Reference ranges for PACs (110-540 pmol/L; 40-195 pg/mL), PRA (60-630 fmol/L/s; 0.3-3 ng/mL/h), and the aldosterone to renin ratio (ARR) (0.3-3.8) were very similar to those established in the same laboratory for humans in a supine position. No breed differences were found. The ARRs in neutered cats were significantly higher than in intact cats, primarily because of low PRA in neutered cats. The ARRs of cats > or = 5 years of age were significantly higher than those of cats < 5 years of age. The plasma concentrations of ACTH, alpha-MSH, and cortisol did not correlate significantly with PAC. Thus, although blood sampling was performed in cats in nonstandardized positions and was associated with a wide variation of stress responses, the references ranges of PAC, PRA, and ARR were similar to the relatively narrow limits established for humans under standardized conditions. The effects of neutering and aging on PRA and ARR warrant further investigation.     

Evaluation of the Cranial Cruciate Ligament Repair System? in Surgery for Laryngeal Hemiplegia in Heavy Draft Horses

The purpose of this study was to evaluate the effect of the canine cranial cruciate ligament repair system on laryngeal hemiplegia in heavy draft horses. Twenty-four heavy draft horses diagnosed with grade 4 laryngeal hemiplegia were allocated to either the prosthetic laryngoplasty (PL) group (n=14) or a canine cranial cruciate ligament repair system (CCCLRS) group (n=10). Right to left angle quotients (RLQs) of abductions of the arytenoid cartilages were endoscopically evaluated before and after surgery. Post-operative RLQs in the CCCLRS group were significantly lower than those of the PL group (P<0.01). The canine cranial cruciate ligament repair system was revealed to be a good surgical procedure for laryngeal hemiplegia in heavy draft horses.     

哈萨克族的草原游牧文化(Ⅱ)——哈萨克族的游牧生产

哈萨克族是世界上最喜欢牲畜和善于饲养牲畜的民族之一。创造了一整套与自然环境相适应的生存技能,使得自然环境始终保持一种良好的存在状态。哈萨克族游牧文化的生产、生活方式及技能是以自然的适应作为前提条件。其实质造就了游牧文化中的物质生产的特征,进而决定了整个生产、生活方式的某些基本特征。如游牧生产具有游移性、实用性、简约性、稳定性;有适应游牧的家畜;有与环境相适应的生活用品,如适应游牧的衣物、食品、毡房等;在畜牧生产中有四季草地的利用标准;畜群结构的控制;转场中的环保习俗;狩猎中的习俗等。哈萨克族有适应游牧生活的独特的民族手工艺产业。