七星瓢虫幼虫空间分布型及抽样技术研究

采用颍次分布X~2检验、Iwao平均拥挤度m~*=a+βx和Taylor幂法则S~2=am~b等8种方法,分析了七块麦田中七星瓢虫幼虫的空间分布型,认为其分布型为负二项分布,且聚集的原因是由于个体之间存在着相互吸引,并确定了代表性较强的棋盘式抽样技术,最佳抽样数量为:Q=28.7088/+0.7552。     

中国长白山区核桃楸种质资源的调查研究

本文概述了中国长白山区核桃楸生长的生态环境和天然的资源概况之后,又对其受各种生态因子以及自然杂交的影响,使得核果产生形状变异的十种类型,进行了较详细的描述,并且还以长白山蛟河地区核桃揪为原料,对其核仁进行了理化分析,结果表明:核桃楸仁油的亚油酸含量均较大豆油、菜籽油、芝麻油为高,作为高营养食用植物油源,综合开发长白山区核桃楸资源应引起重视。     

Imperfect Competition and Common Resource Exploitation—An Analysis of Renewable Resource Management with Non—use Values

This article analyzes the importance of non-use values in the management of natural resources with a model of imperfect competition.By constucting a framework of duopolistic exploiters.the incorporation of non-use values based on self-interest and altruistic motives appears to be significant for determining the degree of inefficiency caused by the problem of common property at the non-cooperative Nash equilibrium.It is found that when the non-use value placed by the altruist exploiter is bounded by that placed by the pure selfinterest exploiter,the effect of market power is dominated by the effect of common exploitation.In this case,the exploiters‘ harvesting strategy will response in the same direction to the change of each other‘s harvesting at the non-cooperative Nash equilibrium.In contrast,when the non-use value placed by the altruist is substantially larger or smaller than that placed by the self-interest exploiter,one exploiter‘s increase in harvesting will lead to a decrease in harvesting of the other exploiter at the non-cooperative Nash equilibrium.     

南昌养殖业资源开发和可持续发展研究—以南昌市为龙头把鄱阳湖区建成动物蛋白仓库

1 南昌地理位置和经济、社会环境南昌是京九线上唯一的省会城市，是一座古老而“年轻”，充满生机活力的文化名城。经过改革开放，南昌的经济、社会建设已发生了巨大变化，进入了全国综合实力50强的行列，目前正朝向开放型、多功能、高效益、强辐射的中心城市发展。南昌地处江西中部偏北，赣江、抚河下游，滨临我国第一大淡水湖泊鄱阳湖西南岸。全境总面积7402.32km2，直辖4县(南昌、新建、进贤、安义)，五区(东湖、西湖、青云谱、湾里、郊区)，有人口415.84万人，耕地22.45万hm2。地理位置优越，交通便利。东北与以上海为中心的长江三角洲…     

单细胞蛋白在饲料中的应用前景

单细胞蛋白含蛋白40％－80％，是饲料生产的上好蛋白原料，且生产资源丰富，开发生产和应用单细胞蛋白，可以缓解粮食不足问题，减少环境污染，促进畜牧业的发展，是人类摆脱大自然的束缚，实现农业工业化的一条新途径，具有广阔的发展前景。