The elevational patterns and key drivers of soil microbial communities strongly depend on soil layer and season

Knowledge about the elevational patterns of soil microbial biomass and communities can facilitate accurate prediction of the responses of soil biogeochemical processes to climate change. However, previous studies that have considered intra- and inter-annual variations have reported inconsistent results on the one hand, and they have paid little attention to the effect of soil layer on the other hand. We, therefore, conducted a 4-year in situ soil core incubation experiment along a 2431-m elevational gradient across the dry valley shrubland, valley-montane ecotone forest, subalpine coniferous forest, alpine coniferous forest, and alpine meadow in an ecologically fragile alpine-gorge region on the eastern edge of the Qinghai-Tibetan Plateau. Soil microbial biomass and community composition in the organic and mineral layers were measured using the phospholipid fatty acids (PLFA) method at five critical periods each year. Our results indicated that soil microbial biomass in the organic layer was the highest in the subalpine coniferous forest, followed by the alpine meadow, alpine coniferous forest, and valley-montane ecotone forest. In contrast, soil microbial biomass in the mineral layer was significantly higher in the alpine meadow than in the other sites. Soil microbial biomass exhibited differential seasonal fluctuations at different elevations, resulting in their elevational patterns being strongly intra-annual and inter-annual dependent. Our results revealed that elevation and seasonality significantly affected soil microbial communities. Seasonality had a more substantial effect than elevation on soil microbial communities during the first 3 years of incubation, whereas the relative importance of seasonal and elevational effects on microbial communities was reversed in the organic layer with incubation time. These results are mainly attributed to the magnitude and direction of effect of environmental variables on soil microbial biomass and communities vary with elevation, soil layer, and sampling time. Briefly, the elevational patterns and dominant factors of soil microbial biomass and communities have intense soil layer and temporal specificity, implying that differential responses of soil biochemical processes to climate change might be observed at different elevations.     

细鳞鱼的增殖实验研究

本文表明了野土种细鳞鱼能在低温性水库中生长,发育与自行繁殖后代。指出了这种典型的非洄游性鲑科鱼类内水面定居的可能性。并指出凡具备全年水温偏低、日平均水温不超过10℃、水质清澈、库区上游常年有大量新水注入、有细鳞鱼自然产卵环境、底栖生物量大、饵科丰富等条件的内水面,采用移殖鱼种的方法是达到保护及增殖细鳞鱼资源的有效途径。     

刺参(Apostichopus japonicus Selenka)南移增养殖若干问题探讨

本文分析了刺参南移浙江省南麂岛养殖、育苗及放流实践。肯定刺参在浙闽沿海养殖前景．提出了利用岛礁放流增殖，主攻池塘（虾塘）改造养参和加强遗传育种研究的建议。     

鲈生物学及池塘养殖技术

报道了鲈繁殖、食性、摄食、生长等习笥及鲈池塘养殖技术，在山东越冬的３种方式、鲈的主要病害及防治。     

黄渤海鲻生长的初步研究

对采自黄渤海沿岩的鲻样品进行了生物学测定，研究了鲻的两性生长，相对增长率，生长指标，生长参数，生长速度和加速度。     

促进水稻耐盐碱细菌S4菌株的筛选鉴定及其效果研究

自然界存在可显著提高植物耐盐碱能力的微生物,利用选择性培养基,在盐含量0.60%、pH 8.5条件下,将供试菌株与水稻幼苗共同培养于人工光照培养箱中,通过根长、株高等生长指标对最优菌株进行筛选,结果从450株分离物中筛选出对盐碱胁迫下水稻生长促进作用最佳的一株菌,S4菌株。经16S rRNA序列相似性比对,S4菌株鉴定为人参土微杆菌（Microbacterium ginsengiterrae）,其可在盐含量4.0%和pH 9.5的盐碱环境中良好生长。在水培试验中,与未接菌盐碱胁迫对照相比,接种S4菌株可提升水稻幼苗干质量4.7%;且在银川盐碱地试验中,接种S4菌株的水稻植株相对未接菌组亩产提升10.8%。     

杉木拟赤杨混交林林分结构和生产力

杉木拟赤杨混交林林分结构及其生产力的研究结果表明：杉木拟赤杨混交林是具有较高生产力，值得南方林区推广的一种针阔混交模式。林分蓄积量以３：１带状混交的最大，卿次为１：１行间混交，１：１株间混交最小；７年生３：１带状混交林林分蓄积量５９．８７ｍ３／ｈｍ２、叶面积指数７．０４、叶净同化率７．１３ｔ／ｈｍ２，分别比杉木纯林提高７．２４％、９．４９％和１６．３１％；混交林林分具有一定成层性，其林分结构比杉林纯林更有利于生物量的积累，提高出材率．     

自然孵化与换壳培养鸭胚胎碱性磷酸酶活性的研究

地黄花叶病毒(Rehmannia mosaic virus,ReMV)是地黄上发生的一种烟草花叶病毒属(Tobamovirus)可能的新病毒。笔者对ReMV的生物学特性进行了初步研究。结果表明,ReMV粒子形态为杆状,可以侵染茄科、番杏科、十字花科和藜科等4科10种植物,其中在茄科的心叶烟、黄花烟、蔓陀罗;番杏科的番杏;藜科的苋色藜和昆诺藜上表现为局部枯斑症状。在红花烟、普通烟、番茄和白菜等植物上表现为系统花叶症状。ReMV的钝化温度为90-95℃,稀释限点为10-5-10-6,20-22℃条件下的体外存活期在60d以上。     

小麦叶鞘枯萎病发生规律及防治技术研究

研究小麦叶鞘枯萎病的田间发生规律,探讨了发病程度和危害损失与环境因子的同时进行人工综合防治技术的研究。研究结果,该病在小麦拔节至孕穗期始发,抽穗期病期快速发展,扬花灌浆期达发病高峰,乳熟后病情基本稳定,该病改天吉温低温病害,其田间发病程度和危害同土壤类型、小麦拔节孕穗期的气温、雨日、雨量、以及施肥水平关系密切;综合防治中应坚持人工调控麦田生态环境为中心,开展健身栽培,在病害始发期和快速扩展期用化学