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

意外的必然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定律或原则之上的，这样一种特定的投入就会产生可预测和一致的产出，但生态系统的一个关键思想是，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在极大的（如宇宙）和极小的（如原子）水平，生态系统以其固有的不可预测性，其中一个方面是突然的，剧烈的，有时是意想不到的变化。这样的事件通常被称为“关键转变”。一个明显的例子是农业系统中害虫的突然爆发。该项目旨在了解害虫系统中这些意想不到的变化的结构，这些变化自古以来就一直困扰着食品生产，目前正威胁着社会上最受欢迎的饮料之一。这个项目使用咖啡农业生态系统作为一个生态系统模型，来询问关键转变（在这种情况下，虫害突然爆发）的经典思想如何反映从基本生态理论中产生的理论结构。在管理系统中，有害生物暴发可能是由临界过渡现象驱动的；虫害问题不是为了响应管理决策而缓慢累积增加，它们似乎经常突然从一个相对稳定的系统（低虫害种群）跳到另一个系统（高虫害种群）。此外，试图扭转这一进程的管理人员可能面临滞后的相关问题：当达到一个管理阈值时，虫害突然爆发，而当该阈值恢复到以前的水平时，虫害却不会以同样的方式自行逆转。墨西哥南部咖啡农场的三种主要害虫都在子系统中联系在一起，这些子系统具有理论结构（模块），每个模块都表明了发生关键转变的条件。该研究试图确定这三个定义良好的模块（子系统）是否表现出关键的转换行为。此外，这项工作的目的是理解当这三个子组件（每个子组件都可以单独显示关键的转变行为）像它们在现实中那样明显耦合时，在更大范围内的含义。该奖项反映了美国国家科学基金会的法定使命，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.