Trade and transport of goods is widely accepted as a primary pathway for the introduction and dispersal of invasive species. However, understanding commodity flows remains a challenge owing to its complex nature, unavailability of quality data, and lack of systematic modeling methods. A robust network-based approach is proposed to model seasonal flow of agricultural produce and examine its role in pest spread. It is applied to study the spread of Tuta absoluta, a devastating pest of tomato in Nepal. Further, the long-term establishment potential of the pest and its economic impact on the country are assessed. Our analysis indicates that regional trade plays an important role in the spread of T. absoluta. The economic impact of this invasion could range from USD 17-25 million. The proposed approach is generic and particularly suited for data-poor scenarios.

中文翻译：

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入侵物种传播背景下的商品流动建模：尼泊尔 Tuta absoluta 研究

货物贸易和运输被广泛认为是入侵物种引入和扩散的主要途径。然而，由于其性质复杂、质量数据不可用以及缺乏系统的建模方法，理解商品流动仍然是一个挑战。提出了一种基于网络的强大方法来模拟农产品的季节性流动并检查其在害虫传播中的作用。它用于研究 Tuta absoluta 的传播，这是一种在尼泊尔的毁灭性番茄害虫。此外，还评估了有害生物的长期定殖潜力及其对国家的经济影响。我们的分析表明，区域贸易在 T. absoluta 的传播中起着重要作用。这次入侵的经济影响可能在 17-2500 万美元之间。