基于树冠变色特征的越冬期雪岭云杉枝干小蠹分布规律及其防控

Crown-discoloration-driven distribution patterns and control of two overwintering bark beetles ( Ips hauseri and Pityogenes spessivtsevi) on Picea schrenkiana stems

摘要

【目的】天山东部雪岭云杉天然林因受天山重齿小蠹与天山星坑小蠹持续为害而日趋衰退。越冬期清理虫源木是重要防控措施，但冬季作业多局限于地上受害木。为精准清除虫源，本研究阐明越冬期两种小蠹在不同受害阶段雪岭云杉枝干中的分布规律，为制定科学、精准的越冬防控策略提供依据。【方法】于越冬初期，依据树冠针叶变色程度（从全绿至全灰）将雪岭云杉样木划分为 5 个受害阶段，共选取 15 株样木。伐倒后对主干分段解剖，并按树冠上、中、下层采集侧枝，系统调查并记录两种小蠹的虫口数量、虫态与分布位置。【结果】越冬初期，天山重齿小蠹与天山星坑小蠹活虫仅分布于早期、中期和晚期受害木中，健康木与枯立木无活虫分布，其中早期受害木为林内越冬虫源的主要载体。两种小蠹在受害木上表现出显著的生态位分化：天山重齿小蠹主要分布于主干中下段（4 ~ 5 m），且几乎全部为成虫；天山星坑小蠹则主要分布于寄主主干中上段及树冠侧枝，在主干垂直分布上则主要集中于 4 ~ 5 m 和 10 ~ 11 m 两个高度区间，在主干 4 ~ 5 m 处以幼虫为主，在主干 10 ~ 11 m 及侧枝中则以成虫为主。【结论】越冬初期，天山重齿小蠹与天山星坑小蠹集中分布于树冠明显失绿变色的受害木上，两种小蠹呈现出显著的生态位分化。在越冬期小蠹的灾害管控实践中，建议以树冠变色特征为指示，优先对早期至晚期受害木实施分级精准清理，并结合枝干部不同虫态的空间分布特征采取差异化处理，以期最大程度压低次年虫口发生基数。

Abstract

[Objective] In the eastern Tianshan Mountains, natural Picea schrenkiana forests are progressively declining as a result of persistent damage by Ips hauseri and Pityogenes spessivtsevi. Removing infested source trees during the overwintering period is an important control measure, but winter operations are largely confined to aboveground damaged trees. To enable the precise removal of these beetle sources, this study clarified the distribution patterns of the two bark beetle species in the trunks and branches of Picea schrenkiana at different damage stages during the overwintering period. The findings provide a basis for developing scientific and precise overwintering control strategies. [Method] In the early overwintering period, Picea schrenkiana trees were assigned to five damage stages according to the degree of crown needle discoloration (from fully green to fully gray), and 15 sample trees were selected in total. After felling, the trunk was divided into sections and dissected, and lateral branches were collected from the upper, middle, and lower crown layers. The abundance, developmental stage, and distribution of the two bark beetle species were then systematically surveyed and recorded. [Result] In the early overwintering period, live I. hauseri and Pityogenes spessivtsevi occurred only in early-, mid-, and late-stage damaged trees, whereas none were found in healthy or standing dead trees. Early-stage damaged trees were the principal reservoir of overwintering beetles within the forest. The two species showed marked niche differentiation on infested trees. I. hauseri was concentrated in the middle and lower trunk (4−5 m) and consisted almost entirely of adults. In contrast, Pityogenes spessivtsevi mainly occupied the middle and upper trunk and the lateral branches of the crown. On the trunk, it was concentrated at two height intervals, 4−5 m and 10−11 m. Larvae dominated at 4−5 m, whereas adults dominated at 10−11 m and in the lateral branches. [Conclusion] In the early overwintering period, I. hauseri and Pityogenes spessivtsevi were concentrated on damaged trees with pronounced crown discoloration, and the two species showed marked niche differentiation. For managing bark beetle damage during the overwintering period, we recommend using crown discoloration as an indicator and prioritizing the graded, precise removal of early- to late-stage damaged trees. Treatments should be differentiated according to the spatial distribution of the different developmental stages on the trunk and branches, so as to minimize the beetle population base in the following year.

关键词

雪岭云杉 / 天山重齿小蠹 / 天山星坑小蠹 / 树冠变色 / 生态位分化 / 越冬分布 / 森林害虫防控

Key words

Picea schrenkiana / Ips hauseri / Pityogenes spessivtsevi / crown discoloration / niche differentiation / overwintering distribution / forest pest control

参考文献

[1] Allen C D, Macalady A K, Chenchouni H, et al. A global overview of drought and heat—induced tree mortality reveals emerging climate change risks for forests [J].Forest Ecology and Management, 2010, 259(4):660-684.

[2] Bentz B J, Régnière J, Fettig C J, et al. Climate change and bark beetles of the Western United States and Canada: direct and indirect effects [J].BioScience, 2010, 60(8):602-613.

[3] Raffa K F, Aukema B H, Bentz B J, et al. Cross—scale drivers of natural disturbances prone to anthropogenic amplification: the dynamics of bark beetle eruptions [J].BioScience, 2008, 58(6):501-517.

[4] Berryman A A. Resistance of conifers to invasion by bark beetle—fungus associations [J].BioScience, 1972, 22(10):598-602.

[5] Christiansen E, Waring R H, Berryman A A. Resistance of conifers to bark beetle attack: searching for general relationships [J].Forest Ecology and Management, 1987, 22(1−2):89-106.

[6] Erbilgin N, Zanganeh L, Klutsch J G, et al. Combined drought and bark beetle attacks deplete non—structural carbohydrates and promote death of mature pine trees [J].Plant, Cell & Environment, 2021, 44(12):3866-3881.

[7] Mitton J B, Ferrenberg S M. Mountain pine beetle develops an unprecedented summer generation in response to climate warming [J].The American Naturalist, 2012, 179(5):E163-E171.

[8] Faccoli M. Effect of weather on Ips typographus (Coleoptera Curculionidae) phenology, voltinism, and associated spruce mortality in the southeastern Alps [J].Environmental Entomology, 2009, 38(2):307-316.

[9] Rouault G, Candau J N, Lieutier F, et al. Effects of drought and heat on forest insect populations in relation to the 2003 drought in Western Europe [J].Annals of Forest Science, 2006, 63(6):613-624.

[10] Hlásny T, König L, Krokene P, et al. Bark beetle outbreaks in Europe: state of knowledge and ways forward for management [J].Current Forestry Reports, 2021, 7(3):138-165.

[11] Singh V V, Naseer A, Mogilicherla K, et al. Understanding bark beetle outbreaks: exploring the impact of changing temperature regimes, droughts, forest structure, and prospects for future forest pest management [J].Reviews in Environmental Science and Bio/Technology, 2024, 23(2):257-290.

[12] Karpov A, Pirtskhalava—Karpova N, Singh V V, et al. Response of mature Norway spruce to experimental thermal and drought stress in relation to Ips typographus attack: crown temperatures and sap flow [J].Forest Ecology and Management, 2026, 600:123290.

[13] Kašák J, Foit J, Holuša O, et al. Scolytus koenigi Schevyrew, 1890 (Coleoptera: Curculionidae): new bark beetle for the Czech Republic and notes on its biology [J].Journal of Forest Science, 2015, 61(9):377-381.

[14] Buhroo A A, Pandit R S, Zubair R M. Morpho—molecular identification of the bark beetle Hylesinus macmahoni (Stebbing, 1909) (Coleoptera: Curculionidae: Scolytinae) infesting Olea europaea subsp. cuspidata (Wall. & G. Don) Cif., along with a brief biological synopsis [J].Folia Forestalia Polonica, 2024, 66(1):1-7.

[15] Kautz M, Peter F J, Harms L, et al. Patterns, drivers and detectability of infestation symptoms following attacks by the European spruce bark beetle [J].Journal of Pest Science, 2023, 96(1):403-414.

[16] Celedon J M, Bohlmann J. Oleoresin defenses in conifers: chemical diversity, terpene synthases and limitations of oleoresin defense under climate change [J].New Phytologist, 2019, 224(4):1444-1463.

[17] Kolb T, Keefover—Ring K, Burr S J, et al. Drought—mediated changes in tree physiological processes weaken tree defenses to bark beetle attack [J].Journal of Chemical Ecology, 2019, 45(10):888-900.

[18] Ott D S, Davis T S, Mercado J E. Interspecific variation in spruce constitutive and induced defenses in response to a bark beetle—fungal symbiont provides insight into traits associated with resistance [J].Tree Physiology, 2021, 41(7):1109-1121.

[19] Aochi M, Takagi E. Host desiccation and interspecific competition limit reproductive performance of a bark beetle[J].Agricultural and Forest Entomology, 2026:afe. 70070.

[20] Safranyik L, Carroll A L. The biology and epidemiology of the mountain pine beetle in lodgepole pine forests[M]//Safranyik L, Wilson W R, eds. The mountain pine beetle: a synthesis of biology, management, and impacts on lodgepole pine. Victoria: Natural Resources Canada, Canadian Forest Service, Pacific Forestry Centre, 2006:3-66.

[21] Grunwald M. Ecological segregation of bark beetles (Coleoptera, Scolytidae) of spruce [J].Journal of Applied Entomology, 1986, 101(1−5):176-187.

[22] Göthlin E, Schroeder L M, Lindelöw A. Attacks by Ips typographus and Pityogenes chalcographus on windthrown spruces (Picea abies) during the two years following a storm felling [J].Scandinavian Journal of Forest Research, 2000, 15(5):542-549.

[23] Byers J A. Chemical ecology of bark beetles [J].Experientia, 1989, 45(3):271-283.

[24] Chansler J F. Cold hardiness of two species of Ips beetles [J].Journal of Forestry, 1966, 64(9):622-624.

[25] Hedgren P O. The bark beetle Pityogenes chalcographus (L.) (Scolytidae) in living trees: reproductive success, tree mortality and interaction with Ips typographus [J].Journal of Applied Entomology, 2004, 128(3):161-166.

[26] Schebeck M, Schopf A, Ragland G J, et al. Evolutionary ecology of the bark beetles Ips typographus and Pityogenes chalcographus [J].Bulletin of Entomological Research, 2023, 113(1):1-10.

基金资助

新疆维吾尔自治区重点研发计划(2026B02001)