特优175高产结构分析和配套栽培技术探讨

特优175分蘖力中强、穗大粒重、株型理想、高产稳产.经调查分析,其高产结构中,以每穗结实粒数的变异(cv=17.20%)最大,与产量相关最密切(r=0.591 1**,对产量的通径(p=1.035 6)和净贡献率(pr=0.612 1)最大;其次为有效穗(cv=10.40%,p=0.709 5,r=0.184 4,pr=0.130 8);千粒重是品种的稳定性状,对产量的贡献有限.每公顷产量7 500 kg左右的适宜产量结构为:每公顷250万穗,每穗结实120粒、千粒重28 g左右.在保持一定的穗数下,较高的每穗结实粒数是高产栽培的主攻重点.配套栽培技术是:(1)适时播种,培育壮秧;(2)适时移栽,合理密植(每公顷基本苗150～180万);(3)合理调控水肥,每公顷施纯氮150～180 kg,氧化钾120～160 kg,五氧化二磷60～80 kg;(4)综合防治病虫害.     

振动深松鼠道犁的试验分析

石河子及周围垦区的土壤粘重且呈盐碱性,由于犁底层的存在,土质很难得到改善。而深松作业则是打破犁底层的主要农业技术措施之一。为此,论述了IZSS-600-3型振动深松鼠道犁的构造和工作原理,分析了试验因素对试验指标的影响,为机具今后在农业生产中的应用和推广提供了依据和参考。     

A novel approach to studying the effects of temperature on soil biogeochemistry using a thermal gradient bar

The temperature dependence of chemical reaction rates and microbial metabolism mean that temperature is a key factor regulating soil trace gas emissions and hydrochemistry. Here we evaluated a novel approach for studying the thermal response of soils, by examining the effects of temperature on gas emissions and hydrochemistry in (a) peat and (b) soil from a Sitka spruce plantation. A thermal gradient was applied along an aluminium bar, allowing soil to be incubated contemporaneously from 2 to 18 °C. The approach demonstrated clear differences in the biogeochemical responses of the two soil types to warming. The peat showed no significant emission of CH₄ at temperatures below 6 °C, while above 6 °C, a marked increase in the rate of release was apparent up to 15 °C (Q₁₀ = 2.5) with emissions being similar between 15 and 18 °C. Conversely, CH₄ emissions from the forest soil did not respond to warming. Nitrate availability in the peat decreased by 90% between 2 and 18 °C (P < 0.01), whereas concentrations in the forest soil did not respond. Sulphate availability in the peat decreased significantly with warming (60%, P < 0.01), while the forest soil showed the opposite response (a 30% increase, P < 0.01). Conventionally, thermal responses are studied by incubating individual soil samples at different temperatures, involving lengthy preparation and facilities to incubate samples at different temperatures simultaneously. Data collected on a given thermal response is usually limited and thus interpolated or extrapolated. The thermal gradient method overcomes these problems, is simple and flexible, and can be adapted for a wide range of sample types (not confined to soil). Such apparatus may prove useful in the optimization of management practices to mitigate the effects of climate change, as thermal responses will differ depending on land use and soil type.     

管道对接环焊缝裂纹的防治措施

针对甬沪宁进口原油管道工程开工初期对接环焊缝常出现裂纹的现象,结合射线检测和解剖结果,对裂纹产生的位置和断口特征进行了具体分析.通过对下向焊焊接工艺和焊口的受力分析,解析出其产生裂纹的原因,提出了相应的防止对策.     

推求合理畦宽的方法及应用

为了寻求合理的节水省时畦宽,以更好地利用现有水源,在1990、1991年试验和实践的基础上,用统计回归分析方法对大城县农田畦田规格进行了分析,求出了合理畦宽,并从灌水持续时间、用电量、提水量等方面对合理畦宽的节水、节能效果进行了分析。     

利用通径分析研究土壤不同形态硫对有机质的影响

用通径分析的方法分析了不同形态硫对土壤有机质的作用。结果表明 :在影响土壤有机质的诸多硫组分中 ,以全硫为主 ,其次是未知态硫和全硫的共同作用 ,再次是碳键硫和全硫的共同作用 ,脂键硫排在第九位。有机硫起主要作用     

甘薯新品种综合评价初探

对福建省新育成甘薯品种应用灰色加权关联度分析法进行综合评估，旨在鉴定新品种在丘陵旱地的适应性以及探讨出一种比较适宜的品种评估方法。结果表明，龙薯1号、莆薯41和泉薯647比较适应东南沿海丘陵旱地生产条件，评估结果与品种的实际表现比较一致。     

甜菜种质资源数量性状遗传距离差异及其应用的研究

对60份参试材料的5个性状主成分分析结果表明,确定甜菜主成分因子有根产量、含糖量和抗褐斑病性;聚类分析结果,按类群间遗传距离大于类群内遗传距离的原则分为6类.类群间的平均遗传距离(?)~2=16.781,大于该平均遗传距离的类群组合有Ⅰ和Ⅳ,Ⅰ和Ⅴ,Ⅰ和Ⅵ,Ⅱ和Ⅵ,Ⅲ和Ⅴ,Ⅲ和Ⅵ,在上述类群间选择亲本有效.     

亚麻工艺长相关性状的通径分析

本试验以6个普通亚麻品种为材料,进行工艺长相关性状的通径分析。结果表明,5个相关性状对工艺长度影响大小顺序为:单株粒重>单株粒数>千粒重>株高>主茎分枝数。降低单株粒重是提高工艺长度的主要途径。在千粒重、单株粒重相对稳定的类型中,选择植株较高、单株粒数较多者,或在株高、单株粒数相对稳定的类型中,选择千粒重较高者是提高工艺长度的重要途径。减少主茎分枝数亦可有效提高工艺长度,但作用较小。