吉林省西部生态环境脆弱区农业发展模式探讨

研究分析了吉林省西部地区生态环境脆弱特征及其对农业发展的影响,并提出该区生态环保型效益农业发展模式以及农业地域结构规划。     

Spatial structure of multispecies distributions in southern California, USA

Analysis of the spatial distribution of all species of conservation importance within a region is necessary to augment reserve selection strategies and habitat management in biodiversity conservation. In this study, we analyzed the spatial aggregation, spatial association, and vegetation types of point occurrence data collected from museum and herbaria records for rare, special concern, threatened, and endangered species of plants, reptiles, mammals, and birds in western Riverside County in southern California, USA. All taxa showed clumped distributions, with aggregation evident below 14 km for plants, 12 km for reptiles, 2 km for mammals, and 10 km for birds. In addition, all combinations of the different species groups showed high positive spatial association. The Santa Rosa Plateau exhibited the highest number of rare, special concern, threatened, and endangered species, and shrubland (coastal sage and chaparral) was the vegetation type inhabited by the most species. Local land use planning, zoning and reserve design should consider the spatial aggregation within and between species to determine the appropriate scale for conservation planning. The higher spatial association between species groups in this study may indicate interdependence between different species groups or shared habitat requirements. It is important to maintain diverse communities due to potential interdependence. The results of the study indicate that concentrating preservation efforts on areas with the highest number of species of concern and the restoration of native shrublands are the most appropriate actions for multiple species habitat conservation in this area.     

Green manure production of Azolla microphylla and Sesbania rostrata and their long-term effects on rice yields and soil fertility

Summary Azolla spp. and Sesbania spp. can be used as green manure crops for wetland rice. A long-term experiment was started in 1985 to determine the effects of organic and urea fertilizers on wetland rice yields and soil fertility. Results of 10 rice croppings are reported. Azolla sp. was grown for 1 month and then incorporated before transplanting the rice and 3–4 weeks after transplanting the rice. Sesbania rostrata was grown for 7–9 weeks and incorporated only before transplanting the rice. Sesbania sp. grew more poorly before dry season rice than before wet season rice. Aeschynomene afraspera, which was used in one dry season rice trial, produced a larger biomass than the Sesbania sp. The quantity of N produced by the Azolla sp. ranged from 70 to 110 kg N ha^-1. The Sesbania sp. produced 55–90 kg N ha^-1 in 46–62 days. Rice grain yield increases in response to the green manure were 1.8–3.9 t ha^-1, similar to or higher than that obtained in response to the application of 60 kg N ha^-1 as urea. Grain production per unit weight of absorbed N was lower in the green manure treatments than in the urea treatment. Without N fertilizer, N uptake by rice decreased as the number of rice crops increased. For similar N recoveries, Sesbania sp. required a lower N concentration than the Azolla sp. did. Continuous application of the green manure increased the organic N content in soil on a dry weight basis, but not on a area basis, because the application of green manure decreased soil bulk density. Residual effects in the grain yield and N uptake of rice after nine rice crops were found with a continuous application of green manure but not urea.     

西藏南迦巴瓦峰地区土壤地理分布规律的研究

西藏东南部的南迦巴瓦峰地区，面积约６．４３×１０＾４ｋｍ＾２。章探讨了土壤垂直带谱的性质和结构特点，土壤水平地带与垂直带的关系，土壤垂直带的结果类型；论述了湿润程度，逆温、人类活动对土壤垂直带影响，以及山体高度和大小与山地土壤分布的关系。     

杀球灵抗鸡球虫的药效研究

采有笼饲试验和围栏试验,研究了一种新的抗球虫药——杀球灵抗鸡球虫的药效。笼饲试验表明:杀球灵抗柔嫩艾美耳球虫的指数为195.6,属于高效抗球虫药.围栏试验表明:杀球灵以1ppm剂量添加于饲料,可有效地控制鸡的3种主要球虫——柔嫩、堆型和巨型艾美耳球虫的混合感染,可阻止死亡、抑制盲肠病变产生和卵囊形成,并能维持正常的增重和饲料转化率。     

江汉平原土地利用变化分析

以江汉平原20世纪809、0年代和2000年3个时期内的土地利用类型动态监测结果为基础,对其进行了利用状况分析、土地利用程度分析、利用程度变化分析和土地利用变化的区域差异分析。结果表明:该区域耕地面积在不断减少,围湖造田的现象依然存在;土地利用程度相对较稳定,属于农业用地类型;土地利用格局尚未完全定型,处于调整期;土地利用变化的区域性差异不明显。     

高校在区域创新系统中的角色定位

高校是区域科技创新体系的重要组成部分。在介绍区域创新系统理论的基础上,对高校在区域创新系统中的角色进行了定位分析。     

棉花杂交种冀H239主要性状特征及栽培技术

笔者以2003～2004年河北省棉花品种区域试验结果为依据,分析了棉花新杂交种冀H239主要性状特征,结果表明,冀H239产量突出,抗病性强,纤维长度、纤维比强度优于对照,马克隆值偏高;苗期、蕾期、花期和铃期棉叶中Bt杀虫蛋白表达量、苗期抗性纯合度均高于抗虫对照品种中棉所41;蕾期和花铃期抗性纯合度与中棉所41差异不显著。提出了与该杂交种配套的栽培技术,以便更好地应用于生产。     

2006年叶菜型甘薯新品种国家区试广西试点的分析

[目的]为了筛选高产优质、抗逆性强的叶菜型甘薯,为其在生产上的推广和应用奠定基础。[方法]通过2006年的国家叶菜型甘薯品种区试,测定福薯10号、福薯11号、广薯菜1号、广薯菜2号、阜菜薯1号、莆薯53和福薯7-6(CK)7个甘薯品种的茎叶产量,并进行品质鉴定。[结果]各参试品种茎叶产量均比对照增加,福薯10号产量最高,单产为29599.5 kg/hm2,比对照增产41.3%。其次是莆薯53和广薯菜2号,单产分别为26899.5和26850 kg/hm2,比对照增加28.4%和28.2%。品质鉴定除阜菜薯1号和广薯菜1号稍差外,其余品种都较优,适于在广西种植。综合排名前3名的是福薯10号、莆薯53和广薯菜2号。[结论]该研究为调整广西甘薯生产的品种结构提供了参考。     

土地生态环境评价指标体系研究及区划应用

以江苏生态省建设和土地利用规划修编为契机,笔者着重研究了土地利用过程中土地生态环境评价的原则、依据及评价指标体系,主要选取土地生态环境物质输入等4个约束层指标和单位土地面积能耗等17个指标层指标,并依据江苏生态省建设目标对各个指标值在2004年现状基础上做了测算和评价。并依据指标体系,对江苏省进行了土地生态环境区划分,主要分为三级,分别为土地生态区、土地生态亚区和土地生态环境区。