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WANG Meiyu ZHAO Tianhong ZHANG Weiwei GUO Dan HE Xingyuan FU Shilei . College of agronomy Shenyang Agricultural University Shenyang China 《生态环境》2007,(1)
近年来大气CO2体积分数不断升高,虽然CO2体积分数升高对植物影响的研究已取得一定进展,但目前针对城市森林树种的相关研究甚少。利用开顶式气室研究了大气CO2体积分数升高对沈阳市城市森林主要树种油松(PinustabulaefomisCarr.)光合生理特性的影响。结果表明,整个生长季内,与对照相比,在大气CO2体积分数为700×10-6条件下,油松叶片的Chla、Chlb及Chl(a b)质量分数提高,Chla/Chlb值降低,而类胡萝卜素质量分数则呈现出降低—升高—降低的趋势;整个处理期间,净光合速率显著提高,提高幅度为23.68%~133.18%(P<0.05或P<0.01);可溶性蛋白质量分数增加,并随着处理时间延长增加幅度增大,在通气40d时就达到差异极显著水平(P<0.01);大气CO2体积分数升高促进了油松叶片中可溶性糖、淀粉的积累;实验中并未观察到光合下调现象。 相似文献
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Summary. Polyphagous caterpillars of the giant geometer
Biston robustum resemble the twigs of their respective food
sources in color and shape. Common predatory ants, including
Lasius and
Formica, were often observed to freely prowl directly on caterpillars bodies, even after antennal contact.
This suggests that the cuticular chemicals of the caterpillars
resemble those of the twigs of the foodplants, so we analyzed
both by GC and GC-MS. The chemical compositions
differed among caterpillars fed on a cherry, Prunus yedoensis,
a chinquapin Castanopsis cuspidata, and a camellia Camellia japonica. The cuticular chemicals of the caterpillars
resembled those of their corresponding food sources.
When the caterpillar diets were switched from the cherry to
camellia or chinquapin at the 4th instars, the caterpillars
cuticular chemicals changed after molting to resemble those
of their respective foods. Caterpillars also changed their
cuticular chemicals when they perched on cherry twigs and
fed on camellia or chinquapin leaves, but not when they
perched on camellia or chinquapin twigs and fed on cherry
leaves. The chemical similarities between the caterpillars
and the twigs were due to the digestion of host leaves, which
indicates that this is a diet-induced adaptation. 相似文献
3.
用单个特异引物扩增桃ACC氧化酶cDNA及其在大肠杆菌中的表达 总被引:1,自引:0,他引:1
用单个特异引物和通用引物oligo(dT)15从桃受伤叶片cDNA中扩增出1.3kb左右大小的片段.将该扩增产物克隆并对重组克隆作酶切分析发现至少可分为3类.用桃ACC氧化酶基因组DNA为探针进行点杂交表明,4,7,9,10,11,12重组质粒能与之杂交,其中7,9,10,11,12号重组质粒酶切图谱与已报导的桃果实成熟相关的ACC氧化酶cDNA基因基本一致,而4号克隆则不同.DNA序列分析和PCR鉴定表明,插入片段均由5′端特异引物单个引物扩增出来,对7号重组克隆插入片段DNA全序列分析表明,7号重组克隆插入片段全长1146bp,包含了除启始密码子外的全部编码区和192bp的3′端非编码区.通过补上起始密码子ATG构建重组表达载体,在大肠杆菌中表达出35×103的非融合蛋白 相似文献
4.
Nitrogen fertilization and winter pruning are commonly used to control crop production in peach [Prunus persica (L.) Batsch] orchards. They are also known to affect the dynamics of Myzus persicae (Sulzer) (Homoptera: Aphididae) aphid populations via bottom-up regulation processes. Interactions between crops and pests can cause complex system behaviour in response to management practices. An integrated approach will therefore improve the understanding of the effects of these two cultural practices on aphid and peach performances.We developed a simulation model that describes the cultural control of interacting peach tree and aphid population dynamics. It uses the principles of common trophic models while gathering available knowledge and explicit assumptions on peach and aphid functioning and the effects of cultural practices.The model was able to qualitatively reproduce the system behaviour observed in the field. It accounted for actions and feedback such as stimulation of foliar growth by winter pruning, consecutive aphid population increase, subsequent damage to foliage, and partial compensatory growth of foliage. The model also reproduced low losses in fruit production due to aphid infestations. However, it called for further integration of ‘long-term’ effects. Analysis of the model showed the complexity of peach tree and aphid responses to leaf N × winter pruning interactions. Simulations indicated that fruit production losses remained low within a range of realistic values of leaf N and pruning intensity, whereas manipulating peach and aphid dynamics, their interactions and their relationships to practices could result in higher losses.The model is useful to evaluate the relevance of cultural practices for a bottom-up regulation of aphid dynamics in crop-pest management. After considering other control methods and fruit quality, it can be used to find a combination of practices that optimises trade-offs between fruit production and environmental conservation goals. A modelling approach that links crop growth and pest population dynamics and integrates management practice effects has strong potential for improving crop-pest management in an integrated crop production context. 相似文献
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理解树木生长对气候变化和人类活动干扰的响应有助于未来森林管理和双碳政策的落实。本文基于采自吕梁山南端的油松(Pinus tabuliformis Carr.)树轮样本建立了标准树轮宽度年表。通过Pearson相关分析发现树轮年表对研究区3—7月土壤湿度(r=0.60,P<0.01,n=37)、5—6月平均最低温度(r=-0.37,P<0.01,n=63)和5月降水量(r=0.31,P<0.05,n=64)响应敏感,说明水分条件(降水和土壤湿度)是影响研究区油松径向生长的主要限制因子,温度则是通过调控土壤湿度进而影响树木径向生长过程。近百年来(1926—2011年),研究区油松发生了三次生长释放事件(1932年,1977—1980年,2001—2011年)和一次生长抑制事件(1991—1994年)。生长释放事件在次数、持续时间和发生强度上都高于生长抑制事件。适宜(不适宜)的水热组合能够促进生长释放(抑制),人类活动干扰也能够诱发生长事件。空间相关分析揭示树轮年表与研究区及周边较大范围的气候环境变化密切相关。本研究对深入了解该地区油松树种生长特征及其对气候与人类活动干扰的... 相似文献
6.
应用油松针叶监测大气二氧化硫污染 总被引:2,自引:0,他引:2
蒋高明 《城市环境与城市生态》1995,8(1):19-22
承德市油松针叶中硫与大气SO2浓度之间存在着很显著的相关性(r=0.7841,P<0.01),利用这一相关性对承德市区42个采样点大气SO2污染状况进行了生物监测,并绘制了城市大气SO2污染分布图,基本符合承德市大气SO2分布规律。 相似文献
7.
相对湿度的研究对理解古气候变化有着重要的科学意义,但是目前国内利用树轮资料重建的历史时期相对湿度变化十分有限。本文利用油松树轮宽度重建了河北青龙地区1890—2012年5—7月的平均相对湿度变化,重建序列的方差解释量为39.1%(减少自由度后为38.0%)。重建序列显示出5个湿润期(1895—1899年,1906—1914年,1924—1926年,1950—1955年,1984—2000年)和5个干旱期(1900—1905年,1917—1921年,1927—1949年,1956—1973年,1975—1981年)。重建序列和观测数据均与邻近研究区的PDSI对应良好,表明该序列具有较强的空间代表性,可以反映河北北部地区的平均相对湿度变化情况。本研究表明研究区相对湿度变化不仅受局地气候控制,还可能受到ENSO影响。 相似文献
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土壤含水量对三种阔叶树苗气体交换及生物量分配的影响 总被引:8,自引:0,他引:8
在温室内用盆栽法研究了土壤含水量对茶条槭、山梨和山桃的气体交换及生物量分配的影响,设置4种土壤水分处理(土壤相对含水量75.0%、61.1%、46.4%和35.4%).结果表明:随土壤含水量降低,3树种苗木净光合速率、蒸腾速率和气孔导度均下降,土壤含水量最低时,茶条槭苗木各生理指标降低幅度最大,山梨和山桃次之.茶条槭和山梨水分利用效率(WUE)随土壤含水量的减少呈降低趋势,山桃WUE呈升高趋势.水分胁迫下,3树种苗木根分配生物量显著增加.茶条槭在水分胁迫下,根冠比增加幅度最大,山梨次之,山桃最小.此外,茶条槭叶形态可塑性强,随土壤含水量降低,茶条槭单叶叶面积和总叶面积显著减小,叶厚度增加.山梨和山桃在水分胁迫下单叶叶面积及总叶面积无显著变化.综合3树种苗木在水分胁迫下的生理和形态指标及生物量分配的变化,茶条槭和山桃对水分胁迫的适应能力强于山梨.表4参31 相似文献