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141.
Simulating the reciprocal interaction of forest landscape structure and southern pine beetle herbivory using LANDIS 总被引:2,自引:0,他引:2
David M. Cairns Charles W. Lafon John D. Waldron Maria Tchakerian Robert N. Coulson Kier D. Klepzig Andrew G. Birt Weimin Xi 《Landscape Ecology》2008,23(4):403-415
The reciprocal interaction of landscape structure and ecological processes is a cornerstone of modern landscape ecology. We
use a simulation model to show how landscape structure and herbivory interact to influence outbreaks of southern pine beetle
(Dendroctonus frontalis Zimmermann) in a landscape representative of the southern Appalachian Mountains, USA. We use LANDIS and its biological disturbance
agent module to simulate the effects of landscape composition (proportion of landscape in host area) and host aggregation
on the size and severity of insect outbreaks and the persistence of the host species, Table Mountain Pine (Pinus pungens Lamb.). We find that landscape composition is less important in the modeled landscapes than host aggregation in structuring
the severity of insect outbreaks. Also, simulated southern pine beetle outbreaks over time tend to decrease the aggregation
of host species on the landscape by fragmenting large patches into smaller ones, thereby reducing the severity of future outbreaks.
Persistence of Table Mountain pine decreases throughout all simulations regardless of landscape structure. The results of
this study indicate that when considering alternative restoration strategies for insect-affected landscapes, it is necessary
to consider the patterns of hosts on the landscape as well as the landscape composition. 相似文献
142.
143.
Zhenchang Liang Chunxiang Yang Jun Yang Benhong Wu Lijun Wang Jieshan Cheng Shaohua Li 《Euphytica》2009,167(1):113-125
Inheritance patterns for table grape anthocyanins were investigated on three cross offspring populations during two successive
years. Sixteen anthocyanins were detected, and all were monoglucoside derivatives. The proportion of anthocyanins in the maternal
parent determined the proportion of anthocyanins in the offspring. But the absolute content of the maternal parent had no
significant effect on progenies. Peonidin 3-O-glucoside and malvidin 3-O-glucoside were the most abundant anthocyanins, not only in the maternal parent but also in the progenies. The presence or
absence of anthocyanins in grape skin was inheritance of a quality character controlled by oligogenes, and anthocyanins content
was a quantitative character controlled by polygenes. Via principal component (PC) analysis, factors that affected the total
content of cross progeny populations were peonidin 3-O-glucoside, malvidin 3-O-glucoside, delphinidin 3-O-glucoside, cyanidin 3-O-glucoside, petunidin 3-O-glucoside, peonidin 3-O-(6-O-coumaryl)-glucoside, and malvidin 3-O-(6-O-coumaryl)-glucoside. Anthocyanins content was a high broad sense heritability character (H2), and H2 was stable in different cross combinations (ranging from 0.65 to 0.98). 相似文献
144.
《愤怒的葡萄》是诺贝尔文学奖得主,美国著名作家约翰·斯坦贝克的代表作品。在这部作品中,作者使用了大量的象征手法来表达作者内心强烈的现实主义人文情怀。本文从作品的叙事脉络出发,探讨文中出现的“陆龟”所富含的象征意义。 相似文献
145.
为探究不同覆盖措施对滴灌条件下酿酒葡萄产量和品质的影响,以7 a生酿酒葡萄“赤霞珠”为供试材料,在宁夏红寺堡区开展田间试验.试验设置3个覆盖措施:秸秆覆盖、地膜覆盖和不覆盖(CK),研究不同覆盖措施对葡萄园区土壤含水率、酿酒葡萄生长发育、产量和品质的影响.结果表明,秸秆覆盖处理表现出最佳的保水效果,其土壤含水率较CK提高12.97%(P<0.05).秸秆覆盖处理株高和新梢生长最高,分别达到175.45 cm和89.64 cm,显著高于地膜覆盖和CK(P<0.05),秸秆覆盖处理较地膜覆盖和CK分别提高26.28%(P<0.05)和19.72%(P<0.05).秸秆覆盖处理单粒质量和产量均为最高,分别达到5.59 g和5.32 t/hm2,分别较地膜覆盖和CK增加7.29%(P<0.05)和12.70%(P<0.05),5.35%(P<0.05)和26.07%(P<0.05).秸秆覆盖处理可溶性固形物、可滴定酸、可溶性糖含量,以及花色苷、总酚和VC质量比分别较CK提高20.06%,5.79%,16.39%,6.98%,... 相似文献
146.
147.
为明确‘赤霞珠’葡萄在河西走廊不同地区的品质差异,连续3 a在武威、张掖和嘉峪关果园采集成熟期葡萄果实进行品质测定和分析。结果表明:不同产地果实中可溶性固形物、还原糖及有机酸含量存在显著差异。张掖地区果实可溶性固形物含量最高(24.81%),武威地区果实可滴定酸含量和葡萄果实总酚含量最高(分别为1.34%和24.06 mg·g-1),张掖地区单宁含量最低(5.57 mg·g-1)。张掖地区果实中葡萄糖、果糖、蔗糖的总含量分别达到71.99、70.51、5.61 mg·g-1,显著高于嘉峪关和武威地区;武威地区葡萄果实酒石酸和草酸的含量较高,分别为8.66 mg·g-1和0.32 mg·g-1,显著高于嘉峪关和张掖。‘赤霞珠’葡萄共检测出36种香气物质,其中包括9种醛、9种醇、4种酯、3种酮、2种酚和9种其他类化合物,各地区香气物质的类型及总量均表现为嘉峪关>张掖>武威。整体而言,张掖地区‘赤霞珠’果实品质较好,而嘉峪关地区‘赤霞珠’芳香物质积累较多。 相似文献
148.
149.
研究叶幕整形方式对厂形树形红色酿酒葡萄叶幕和果域微环境、光合特性、果实品质的影响,为提高新疆酿酒葡萄品质提供有效方法。设置篱壁形和V形2个叶幕整形方式,于果实膨大期、转色期、成熟期对叶幕下果域温度、湿度以及2种叶幕形不同位置叶片光合有效辐射强度与光合生理指标进行测定;于果实成熟期对果实外观品质及可溶性固形物与可滴定酸,果皮和种子中的黄酮、多酚、原花青素、单宁等含量进行测定。试验结果表明,与篱壁形叶幕相比,V形叶幕改善叶幕整体光照情况较好,可提高日差值、果域湿度、叶幕内部叶片的光合能力、果穗松散度、可溶性固形物、可滴定酸和酚类物质含量。因此在新疆天山北麓生态条件下,采用V形叶幕整形方式更有助于提高果实品质。 相似文献
150.
Randomly amplified polymorphic DNA (RAPD) was employed to detect molecular markers linked to anthracnose ( Spheceloma ampelinum de Bary) resistant gene in the native wild grapes ( Vitis L. ) of China. RAPD marker OPJ13-300 was linked to anthracnose resistant gene using 90-3 cross F1 V. quinquangularis Rehd (shang-24) × V. vinifera (Longyan). The marker was verified in 90-3 cross F1, Chinese wild grapes and V. riparia and European grape cuitivars. This work has provided a solid basis for molecular marker-assisted selection (MAS) to disease resistance and cloning of disease resistant genes. 相似文献