洞庭湖区东方田鼠对敌鼠钠盐的敏感性分析

为了有效使用抗凝血灭鼠剂防治鼠害,采用强制喂食法将0.025％敌鼠钠盐毒饵分别连续喂食不同性别的成年东方田鼠1、2、4、6和8d,记录东方田鼠取食和死亡情况,并分析洞庭湖区东方田鼠对敌鼠钠盐的敏感性.结果显示:东方田鼠的毒饵取食量有下降的趋势,但不显著;不同性别东方田鼠对敌鼠钠盐的敏感性无显著差异,合并雌、雄东方田鼠数据,其LFP50和LFP99的估计值分别为0.60 d和5.70 d;东方田鼠取食毒饵后,死亡高峰期出现在第4～7天.研究表明洞庭湖区东方田鼠对敌鼠钠盐无抗性,0.025％敌鼠钠盐能够有效防治该地区东方田鼠.     

水土保持植物──刺梨的早实丰产研究

该根据定位观测和实地调查资料，分析了刺梨的生长状况与生态条件的关系，在汉中地区连续进行的刺梨栽培技术研究表明：刺梨生长与土壤含水量，气温，施肥，良种，栽培技术有密切关系。为了达到早实丰产，特提出相应的刺梨栽培措施。     

Tillage – impact on infiltration of the Loess Plateau of China

In arid and semiarid regions, water infiltration is often affected by the soil surface conditions, such as the soil crusts and soil roughness. The objective of this laboratory study was to assess the effects of soil crusts and tillage treatments on soil infiltration in the Loess Plateau of China. A simulated rainfall storm at 80 mm h^?1 rate was applied to soil boxes set to slopes of 5°, 10°, 15° and 20° with two soil surface conditions (crusted and uncrusted) and three tillage treatments (contour tillage [CT], artificial digging [AD] and straight slope [SS]) to investigate the infiltration rates. The results show that the infiltration rate was always lower under the SS treatment than under the CT and AD treatments. The time interval to the steady state was shorter under the SS (10 min) than under the CT and AD treatments (15–20 min). The final infiltration rate was nearly the same under the CT treatment and AD treatment; whereas, the SS treatment resulted in the lowest final infiltration rate. The infiltration rates were always greater in soils without crusts than in soils with crusts. The slopes, soil crusts and tillage treatments had significant (p < 0.001) effects on the cumulative infiltration rates. The combined effects of the slopes and tillage treatments on the cumulative infiltration rates were much more significant (p < 0.01) than the other combined effects (p < 0.05).     

Spatial α-diversity patterns of diverse insect taxa in Northern China: Lessons for biodiversity conservation

Current approaches in terrestrial biodiversity conservation focus predominantly on plants and vertebrates. While these groups account for less than 4% of the estimated global species richness, it is commonly argued that especially the species richness in higher plants is a suitable indicator of overall biodiversity. We tested this assumption, investigating species richness and equitability patterns in three highly species-rich insect families and their links with the vegetation and other environmental factors. Vegetation surveys were combined with pitfall and light trapping to establish the α-diversity of ground beetles, geometrid moths and arctiid moths on 48 plots at varying altitudes between Beijing and the Inner Mongolian Plateau. Soil pH and nutrient status were also recorded. The α-diversity patterns in the three insect families were non-congruent, and links with phytodiversity were weak. The spatial α-diversity patterns in each of the three insect families were significantly correlated with the species density of individual plant families. These links varied between the three insect taxa and were mostly negative in moths. Furthermore, geometrid moth diversity decreased with increasing elevation and decreasing soil pH. Strongly diverging α-diversity patterns across different insect taxa illustrate that it is impossible to find a simple surrogate representing cross-taxon diversity for these highly diverse groups. Furthermore, phytodiversity and vegetation composition appear to play a limited role in governing insect diversity patterns. These results underline the significant risk that current plant-focused approaches in terrestrial biodiversity conservation are inadequate in addressing the conservation needs of the vast majority of species on earth.     

弧型齿残膜捡拾滚筒捡膜的机理

对弧型齿残膜清理滚筒捡膜齿的轴向排列、滚筒转速、捡膜齿运动轨迹和各相关参数进行分析研究,初步找出弧型捡膜齿满足要求的排列布置、滚筒转速和合理的入土深度,确定了残膜回收机具的运动参数λ范围,为残膜清理滚筒的设计提供了理论依据。试验表明,所设计的残膜回收机具运动参数是合理的,在保证膜土分离效果好和较高残膜捡拾率的前提下可显著提高工作效率。     

彩纸对茶尺蠖幼虫诱集效率的研究

本文研究了不同颜色彩纸在室内、野外对茶尺蠖幼虫的诱集以及彩纸与茶树共存时对茶尺蠖的竞争诱集。结果表明,不同颜色纸对茶尺蠖一龄幼虫有不同的诱集率,柠檬黄色纸诱引力最大,土黄、黄绿色纸次之。柠檬黄、土黄、黄绿色纸与茶树竞争诱集时,彩纸比寄主植物诱引力大。     

桃潜叶蛾发生及防治技术研究

桃潜叶蛾在平谷县以成虫越冬,１ａ发生６代。成虫有多次交尾习性,趋光性强,迁移能力较强。幼虫可为害桃、杏、李及榆叶梅等叶片,幼虫天敌优势种为姬小蜂,寄生率可达３６．６％。叶片受害后,光合强度降低２０．８％,产量降低１８．３％。生产上,５月下旬桃潜叶蛾性诱剂诱蛾高峰日,用２５％灭幼脲Ⅲ号悬浮剂１５００～２０００倍液防治;８月中下旬,性诱剂诱蛾激增日开始调查虫（卵）叶率,超过５％时,用２５％灭幼脲Ⅲ号悬浮剂１５００～２０００倍液,加８０％敌敌畏乳油１０００倍液或５％高效氯氰菊酯乳油１５００倍液防治,好叶率可达９５％以上。     

孜然套种糯玉米间毛豆高效栽培技术

孜然芹．糯玉米．毛豆三种作物在一个生产年度内在同一田块上种植,能显著提高光合产量,土地利用率和经济效益。本文主要对孜然套糯玉米再间作毛豆的栽培技术和生产环节进行了详细阐述,并提出了一些高效的耕作和管理思想,以期为生产户服务。     

一种利用流式细胞术鉴定梨倍性的方法

流式细胞术鉴定植物染色体倍性的方法广泛应用于果树多倍体育种中,然而相关流式细胞术鉴定梨染色体倍性的方法还没有系统的研究。以梨树叶片为试材系统优化了各个流式细胞术关键实验节点,结果表明：实验材料选取当年春季新梢第3~5 片梨树嫩叶,尤其是大棚新梢嫩叶最好;叶片前处理时用蒸馏水、去离子水依次洗净叶片表面后,再用去离子水浸泡10 min;使用WPB解离液对梨叶片细胞核进行提取后,用500 目滤膜过滤2 次,离心1 次后用流式细胞仪进行检测可得到理想的实验结果。该方法步骤简单、结果可靠,是一种快速、高效的梨染色体倍性鉴定的方法,可广泛用于梨树多倍体鉴定。     

营林技术决策系统的研究与开发

A set of forestation decision-making system which covers 140 tree species growing extensively in Zhejiang Province including coniferous forest, broad-leaf forest, production forest, and bamboo forest, was developed by cooperation of silvicultural techniques and computer programming based on the experience of forestry management and mathematical models. It can be easily operated to help user selecting tree species in given site types and optimize their benefits, which advances the efficiency of forestation and improves the rationality of decision-making.