Abstract In the United States, the average field size has roughly doubled from the 1980s to the mid-2000s, while average cropland has stayed the same. This will likely influence how semi-natural habitats and edges affect local patterns and processes such as natural pest control or pest densities.We hypothesized that densities of two cotton pests, cotton fleahopper (Pseudatomoscelis seriatus) and verde plant bug (Creontiades signatus) (Hemiptera: Miridae), and corresponding cotton injury in a cotton agroecosystem were affected by field edge, ecotone type (described by the neighboring habitat), and the influence of ecotone type on edge effects. Studies over 2 yr using transect and random point sampling indicated that densities of both insects declined significantly and in a linear fashion from the cotton field boundary (0 m) to field interior (200–300 m from field edge). The decline was influenced by ecotone type for cotton fleahopper. Pest densities in cotton at the interface with semi-natural habitat were higher but declined at a greater rate into the cotton field interior compared to densities seen at the interfaces with sorghum or another cotton field. These effects were also observed for verde plant bug and the cotton boll injury it causes. Regardless of the pest densities near the field edge and the rate of decline into the field interior, densities beyond 100 m into the field were up to 70% less than field edges for both insect species and for boll injury. Potential for land managers to improve sampling efficiency when scouting is apparent. For example, pest species may be at economic threshold in certain parts of the field but not others, leading to different management decisions in larger fields. Therefore, for cotton fleahopper and verde plant bug, edges should be the focus of initial pest detection and sampling, and interior field sampling may only be required when edges are above the economic threshold.

中文翻译：

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田间边缘和田间交错带类型对两种棉花食草动物的影响：棉花跳蚤、Pseudatomoscelis seriatus（半翅目： Miridae）和 Verde Plant Bug、Creontiades signatus

摘要 在美国，平均田地面积从 1980 年代到 2000 年代中期大约翻了一番，而平均耕地面积保持不变。这可能会影响半自然栖息地和边缘如何影响当地模式和过程，例如自然害虫控制或害虫密度。我们假设两种棉花害虫的密度，棉跳蚤 (Pseudatomoscelis seriatus) 和绿色植物虫 (Creontiades signatus) (Hemiptera) : Miridae) 和棉花农业生态系统中相应的棉花损伤受田间边缘、交错带类型（由邻近栖息地描述）以及交错带类型对边缘效应的影响。使用横断面和随机点采样进行的超过 2 年的研究表明，这两种昆虫的密度从棉田边界（0 米）到田地内部（距离田地边缘 200-300 米）均呈线性下降。下降受到棉跳蚤的生态系统类型的影响。与在高粱或其他棉田界面处看到的密度相比，与半自然栖息地界面处的棉花害虫密度较高，但进入棉田内部的病虫害密度下降速度更快。对于佛得角植物病虫害及其引起的棉铃损伤也观察到了这些影响。不考虑田边附近的害虫密度和田间内部的下降速度，田间 100 m 以上的密度比田边的昆虫物种和棉铃伤害低 70%。土地管理者在侦察明显时提高采样效率的潜力。例如，害虫物种可能在田地的某些部分处于经济阈值，而在其他部分则不然，导致在更大的田地中做出不同的管理决策。因此，对于棉花跳蚤和绿叶病虫，边缘应该是初始害虫检测和采样的重点，只有在边缘高于经济阈值时才需要进行内部田间采样。