海拔和肥料互作对美引烤烟品种经济性状的影响

以美引品种NC196和NC471为材料,研究了不同海拔高度（1 489 m和1 883 m）和肥料水平对其主要经济性状的影响。结果表明：NC196对海拔高度较敏感,而NC471对肥料较敏感;2个美引品种在低海拔烟区种植的均价、上等烟比例均高于高海拔烟区;NC196在低海拔的中、高肥力水平条件下栽培,经济性状相对较好,NC471在高肥力水平条件下栽培,经济性状相对较好。     

Exploring the use of a dialogue process to tackle a complex and controversial issue in forest management

This article explores the use of a dialogue process to approach complex issues related to forest management. An interdisciplinary research team set up an experimental dialogue process concerning the use of introduced tree species in Southern Sweden for the purposes of climate change adaptation. The process involved stakeholders at a regional level, including those with divergent opinions regarding introduced tree species and their use in forestry. Through a process of repeated meetings and exchanges with researchers, the participant's knowledge was deepened and group relationships developed such that the group was able to jointly formulate a set of policy recommendations. The investigation revealed that dialogue processes may improve decision-making by identifying priorities for action or further research. However, when a collaborative process targets complex environmental issues on larger geographical and temporal scales, as matters about forests typically do, a collaborative process must be integrated with external actors and institutions in order to attain tangible outcomes. Consequently, to fully access the benefits of using collaborative processes to handle complex challenges in forest policy and management, the connections between political sphere, the private sector, authorities and research institutions must be concretely established.     

加快转变我国花卉产业增长方式的必要性及途径

加快花卉产业增长方式转变是进一步发展我国花卉产业的迫切任务,花卉产业要从单纯追求量的扩张转变,向质的提升。技术进步是花卉产业转变增长方式的关键,引进技术可以提高创新开发的起点,使一国在高水平上选择和利用国外最新科技成果,推进自主开发,缩短同发达国家的差距。     

闽南沿海沙地引种树种的评价

对闽南沿海沙地10种引种造林树种的速生性、丰产性和适应性进行了调查,并采用多目标决策方法进行了闽南沿海沙地引种树种评价研究.结果表明:在10种引种树种中,厚荚相思速生丰产性和适应性得分最高,综合评价值最大,纹荚相思综合评价值居第2,柠檬桉综合得分值最低;厚荚相思、纹荚相思和巨尾桉为闽南沿海沙地1级最适宜造林树种,刚果12号桉、大叶相思和马占相思为2级次适宜造林树种,毛娟相思、肯氏相思、卵果松和柠檬桉为第3级造林树种.     

亚蔬甜椒引进品种比较试验

5个从台湾亚洲蔬菜研究发展中心引进的常规甜椒品种在2009年秋进行了品种比较试验,结果表明:这5个引进品种的前期产量、总产量均未超过对照,说明这5个引进品种暂时不宜作为商品品种来利用;单从这5个引进品种来看,表现最好的是ISPN8-5,前期产量和总产量均最高,商品性状较好,果实绿色,灯笼形,且果实硬度很好,该品种作为甜椒的育种材料,有很好的利用价值;从甜椒育种材料来看,ISPN8-4果色淡黄,粗牛角形,前期产量和总产量也较高,这种甜椒材料在本地较少,可以作为甜椒的储备材料,待以后加以利用。     

Fate and legacy of an invasion: extinct and extant populations of the soft‐shell clam (Mya arenaria) in Grays Harbor (Washington)

1. The soft‐shell clam, Mya arenaria, was intentionally introduced to Washington State during the mid‐1870s. Presently, extensive shell deposits cover parts of the intertidal flats of Grays Harbor, an estuarine ecosystem that has received much attention because of its role as nursery ground for Dungeness crab (Cancer magister), a commercially significant species. 2. Preliminary observations revealed that shells in the deposits belonged to clams that were much larger than extant conspecifics. Shell deposits and extant populations have spatially disjoint distributions; few individuals are found living within the deposits. The purpose of our study was to determine the cause of the different size characteristics between extinct and extant clams, when and how the deposits originated, and why the extant population does not prosper in what appears to be prime habitat. 3. We (i) surveyed extant populations and shell deposits, (ii) followed the extant population through periodic sampling over a 3‐year period, (iii) investigated growth and survival in extant and extinct populations, (iv) experimentally manipulated growth conditions, and (v) searched archival sources for information about the origin of the deposits. 4. We conclude that extinct clams grew faster and lived longer, apparently because they occupied the best habitats available. Archival records suggest that the population expanded rapidly during the period around 20 years after its introduction, but was decimated between 1895 and 1897 by a mass‐mortality episode that resulted in the formation of the deposits. The population since then has never rebounded in its prime habitat, in spite of potential settlers being regularly available. 5. Dungeness crab larvae settle preferentially in the shell deposits, where the abundance of 0+ age juveniles is orders of magnitude higher than in the adjacent flats. We hypothesize that predation by juvenile crabs limits clam recruitment. 6. The introduction of Mya to Grays Harbor during the 1870s has had long‐lasting effects, which persist a century after their once large populations were decimated by a mass‐mortality event. Copyright © 2000 John Wiley & Sons, Ltd.     

伊犁州引进杨树品种聚类筛选

【目的】对新疆伊犁州引进的426个杨树品种（无性系）两年生林木生长特性进行调查,筛选出速生品种,为该地区杨树的良种选择和遗传育种提供理论依据。【方法】根据杨树品种两年生林木生长状况,采用K-means聚类方法对树高和胸径进行聚类分析。【结果】聚类结果可将426个杨树品种两年生林木分为三大类：第Ⅰ类为生长快类,树高年均生长量为4.21 m,胸径年均生长量为4.89 cm;第Ⅱ类为生长较快类,树高年均生长量为3.57 m,胸径年均生长量为3.84 cm;第Ⅲ类为生长慢类,树高年均生长量为2.81 m,胸径年均生长量为2.52 cm。筛选出杨树优良品种（无性系）220个,其中树高和胸径生长快型的95个,树高和胸径生长较快型125个,占总数的50%以上。【结论】初步筛选出220个杨树优良品种,这些杨树品种生长快,抗逆性强,适宜在伊犁河流域栽培种植。     

火炬松引种家系速生性和抗病性的综合选择

在全国火炬松种源试验的基础上，对福建省1996年引种的火炬松家系进行速生性和抗病性综合评价。由遗传增益可知，引种火炬松家系的平均生长表现优于早期引进树种湿地松和当地树种马尾松。方差及遗传参数分析表明，树高、胸径、冠幅、材积、松赤枯病和松落针病等性状在家系间均达显著水平，各生长性状的遗传力均在0．50以上，病害则受中度偏下的遗传力所控制。各生长因子及冠幅间呈极显著正相关，松赤枯病和松褐斑病处于发病初期，还没有对生长造成显著负影响，松落针病与各生长因子呈显著负相关。运用遗传距离分析的方法，根据主成分值综合选出了23、24、22、20、25号5个优良家系，其速生性极好，极抗松落针病，较抗松赤枯病和松褐斑病。     

Evaluating risks to seabirds on the urban–coastal interface: Modelling dog attacks on little penguin populations in Tasmania

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