The Ecology of Critical Transitions in Pest Control in The Coffee Agroecosystem

意外的不可避免性是生态系统的一个特征。虽然大多数科学都是建立在一套规则的法律或原则，使一个特定的输入结果在一个可预测的和一致的输出，生态系统的关键思想之一是，这种固有的可预测性经常被违反，主要是因为它们包含复杂的相互联系。因此，虽然物理学和天文学，例如，正确地庆祝他们的能力，作出精确的预测发生了什么事在非常大的（例如，宇宙）和极小（例如，在原子水平上，生态系统以其固有的不可预测性而闻名，其中一个方面是突然的，剧烈的，有时是意想不到的变化。这类事件通常被称为“关键转变”。“一个明显的例子是农业系统中突然爆发的害虫。这个项目试图了解这些意想不到的变化在害虫系统中的结构，这些害虫系统从远古时代就一直困扰着粮食生产，目前威胁着社会最喜爱的饮料之一。这个项目使用咖啡农业生态系统作为模型生态系统，询问关键转变的经典思想（在这种情况下，突然的害虫爆发）如何反映从基本生态理论中出现的理论结构。害虫在管理系统中的爆发可能是由关键的过渡现象驱动的，而不是在管理决策中缓慢积累的害虫问题的增加，往往他们似乎突然从一个相对稳定的系统（低害虫种群）跳到另一个（高害虫种群）。此外，设法扭转这一进程的管理人员可能面临滞后的相关问题：当达到管理阈值时突然爆发的虫害不会以与阈值恢复到先前水平相同的方式逆转。墨西哥南部咖啡农场的三种主要害虫都连接在具有理论结构（模块）的子系统中，每个子系统都表明了发生关键转变的条件。研究旨在确定这三个定义良好的模块（子系统）是否表现出关键的过渡行为。此外，当这三个子组件中的每一个都可以单独地显示出关键的转变行为时，这项工作的目的是在更大的范围内理解其影响，因为它们显然是在现实中耦合。该奖项反映了NSF的法定使命，并通过使用基金会的知识价值和更广泛的影响审查标准进行评估，被认为值得支持。

The inevitability of surprise is a characteristic of ecological systems. While most sciences are founded on a regular set of laws or principles such that a particular input results in a predictable and consistent output, one of the key ideas of ecological systems is that this inherent predictability is frequently violated, mainly because of the complex interconnections they contain. Thus, while physics and astronomy, for example, rightly celebrate their ability to make precise predictions about what happens at extremely large (e.g., the universe) and extremely small (e.g., atoms) levels, ecological systems are known for their inherent unpredictability, one aspect of which is sudden, drastic, and at times unexpected change. Such events are frequently referred to as a "critical transition." An evident example is the sudden outbreak of pests in agricultural systems. This project seeks to understand the structure of these unexpected changes in the pest systems that have generally plagued food production since times immemorial and that currently threaten one of society's favorite beverages.This project uses the coffee agroecosystem as a model ecosystem, to ask how classical ideas of critical transitions (in this case, sudden pest outbreaks) reflect theoretical constructs that emerge from basic ecological theory. Pest outbreaks in managed systems are potentially driven by critical transition phenomena; rather than a slowly accumulating increase in pest problems in response to management decisions, frequently they seem to suddenly jump from one relatively stable system (low pest population) to another one (high pest population). In addition, managers seeking to reverse this process, may face the related problem of hysteresis: the sudden pest outbreak when a management threshold is reached does not reverse itself in the same way when that threshold reverts to its previous level. The three major pests on the coffee farms of southern Mexico are all connected in subsystems that have theoretical structures (modules), each of which suggests conditions under which critical transitions will occur. The research seeks to determine whether these three well-defined modules (subsystems) demonstrate critical transition behavior. Furthermore, the work aims to understand implications at a larger scale when these three subcomponents, each of which separately can be expected to show critical transition behavior, are coupled as they obviously are in reality.This award reflects NSF's statutory mission and has been deemed worthy of support through evaluation using the Foundation's intellectual merit and broader impacts review criteria.