Data from: Differential responses of herbivores and herbivory to management in temperate European beech

Forest management not only affects biodiversity but also might alter ecosystem processes mediated by the organisms, i.e. herbivory the removal of plant biomass by plant-eating insects and other arthropod groups. Aiming at revealing general relationships between forest management and herbivory we investigated aboveground arthropod herbivory in 105 plots dominated by European beech in three different regions in Germany in the sun-exposed canopy of mature beech trees and on beech saplings in the understorey. We separately assessed damage by different guilds of herbivores, i.e. chewing, sucking and scraping herbivores, gall-forming insects and mites, and leaf-mining insects. We asked whether herbivory differs among different forest management regimes (unmanaged, uneven-aged managed, even-aged managed) and among age-classes within even-aged forests. We further tested for consistency of relationships between regions, strata and herbivore guilds. On average, almost 80% of beech leaves showed herbivory damage, and about 6% of leaf area was consumed. Chewing damage was most common, whereas leaf sucking and scraping damage were very rare. Damage was generally greater in the canopy than in the understorey, in particular for chewing and scraping damage, and the occurrence of mines. There was little difference in herbivory among differently managed forests and the effects of management on damage differed among regions, strata and damage types. Covariates such as wood volume, tree density and plant diversity weakly influenced herbivory, and effects differed between herbivory types. We conclude that despite of the relatively low number of species attacking beech; arthropod herbivory on beech is generally high. We further conclude that responses of herbivory to forest management are multifaceted and environmental factors such as forest structure variables affecting in particular microclimatic conditions are more likely to explain the variability in herbivory among beech forest plots.

森林经营不仅会影响生物多样性，还可能改变由生物介导的生态系统过程——即植食作用（herbivory）：由植食性昆虫及其他节肢动物（arthropod）类群移除植物生物量的过程。为揭示森林经营与植食作用之间的普遍关联，本研究在德国3个不同区域的105个欧洲山毛榉（European beech）主导样地中，针对成熟山毛榉的向阳冠层（canopy）以及林下的山毛榉幼树，开展了地上节肢动物植食作用调查。我们分别评估了不同植食者功能群（guild）造成的危害，包括咀嚼式、刺吸式、刮食式植食者，造瘿昆虫与螨类，以及潜叶昆虫。我们探究了不同森林经营模式（未经营林、异龄经营林、同龄经营林）间以及同龄林内不同龄级间的植食作用差异。此外，我们还检验了区域、层位与植食者功能群之间关联的一致性。平均而言，近80%的山毛榉叶片出现植食危害，约6%的叶面积被取食。其中咀嚼危害最为常见，而刺吸与刮食危害则极为少见。总体而言，冠层的危害程度高于林下，尤其体现在咀嚼、刮食危害以及潜叶痕迹的发生情况上。不同经营模式林分的植食作用差异较小，且经营对危害的影响在区域、层位与危害类型间存在差异。协变量（covariates）如林木蓄积量、林木密度、植物多样性等对植食作用的影响较弱，且其效应因植食危害类型而异。本研究得出结论：尽管危害山毛榉的节肢动物物种数量相对较少，但山毛榉上的节肢动物植食作用整体水平较高。我们进一步认为，植食作用对森林经营的响应具有多面性，而影响微气候条件等森林结构变量的环境因素，更能解释山毛榉林样地间植食作用的差异。