Conservation value of low-productive forests measured as the amount and diversity of dead wood and saproxylic beetles

In many managed landscapes, low-productive land comprises most of the remaining relatively untouched areas, and is often over-represented within protected areas. The relationship between the productivity and conservational value of a site is poorly known; however, it has been hypothesized that biodiversity increases with productivity due to higher resource abundance or heterogeneity, and that the species communities of low-productive land are a nested sub-set of communities from more productive land. We tested these hypotheses for dead wood-dependent beetles by comparing their species richness and composition, as well as the amount and diversity of dead wood, between low-productive (potential forest growth &lt; 1 m3 ha-1 year-1) and productive Scots pine-dominated stands in Sweden. We included four stand types: stands situated on (i) thin soils and (ii) mires (both low-productive), (iii) managed stands, and (iv) unmanaged stands set aside for conservation purposes (both productive). Bee...在诸多人工管理的景观中，低生产力土地占据了剩余未受干扰区域的绝大多数，且在保护区内的占比往往偏高。目前学界对某一区域的生产力与其保护价值之间的关联尚不清楚；不过已有假说提出，生物多样性会随生产力提升而增加，这源于资源丰度更高或异质性更强，且低生产力生境的物种群落是高生产力生境物种群落的嵌套亚群落。本研究以瑞典境内的欧洲赤松（Scots pine）优势林分为研究对象，对比低生产力（森林潜在生长量<1立方米·公顷⁻¹·年⁻¹）与高生产力林分中依赖枯木的甲虫的物种丰富度、群落组成，以及枯木的数量与多样性，以此检验上述两项假说。本研究纳入四类林分：（i）生长于薄土层的林分与（ii）泥炭地林分（二者均为低生产力林分），（iii）人工经营林分，以及（iv）为保护目的预留的天然林分（二者均为高生产力林分）。Bee...