The evolution of group cooperation is still an evolutionary puzzle and has been studied from the perspective of not only evolutionary ecology but also social sciences. Some socio-ecological problems are caused by collapse of group cooperation. By applying theoretical studies about the evolution of cooperation, we can elucidate what causes the problems and find solutions. One of the appropriate examples is maintaining rice paddy field landscapes, which are a grand spectacle in Asia, and some are UNESCO world heritage sites. These magnificent landscapes and the associated biodiversity are at risk of abandonment for social and financial reasons. Rice paddy fields can be preserved not only by regular cultivation, which requires farmers to invest effort in cultivation, but also by the maintenance of common facilities such as irrigation canals. To investigate how this landscape might be preserved, we developed an agent-based model in which each farmer makes two types of efforts: an effort for land cultivation and an effort for collective action such as common facility maintenance. Additionally, we consider the side effects of rice production such as field deterioration from abandonment and water use competition. These factors determine the utility of each player who imitates the level of efforts necessary to invest in land cultivation and common facility maintenance of one with higher utility. This decision-making of each player can be described by the evolutionary game theory. We find that maintenance effort promotes cultivation effort, but not vice versa, even though we usually consider that each farmer's cultivation effort makes rice field landscape sustainable. We also find that if players and their near neighbors are responsible for maintaining their common facilities together, they continue to maintain them and cultivate, but if all players are responsible for maintaining all facilities in the whole farmland, players are likely to quit facility maintenance and stop cultivation. Competition for water use among all players, however, promotes cultivation more than competition among neighbors only. Therefore, rice paddy field landscapes can be sustainable if neighbors, but not the whole players, are responsible for maintaining their common facilities and cooperate together, and if the water usage of all players, but not neighbors, influences the productivity of each rice field.

中文翻译：

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稻田保值保值：运用进化博弈论研究如何防止农民弃田。

群体合作的进化仍然是一个进化难题，不仅从进化生态学的角度，而且从社会科学的角度进行了研究。一些社会生态问题是由群体合作的崩溃引起的。通过应用关于合作演变的理论研究，我们可以阐明导致问题的原因并找到解决方案。一个适当的例子是维护稻田景观，这是亚洲的一大奇观，其中一些是联合国教科文组织世界遗产。由于社会和经济原因，这些壮丽的景观和相关的生物多样性面临被遗弃的风险。保留稻田不仅可以通过定期耕作，需要农民投入精力耕种，还可以通过维护灌溉渠等公共设施。为了研究如何保护这一景观，我们开发了一个基于代理的模型，在该模型中，每个农民都做出两种类型的努力：一种是土地耕种的努力，另一种是集体行动的努力，例如共同设施维护。此外，我们还考虑了水稻生产的副作用，例如弃耕和用水竞争造成的田地退化。这些因素决定了每个参与者的效用，他们模仿投资于具有更高效用的土地耕种和公共设施维护所需的努力水平。每个参与者的这种决策可以用进化博弈论来描述。我们发现维护努力促进了耕作努力，但反之则不然，尽管我们通常认为每个农民的耕作努力使稻田景观可持续。我们还发现，如果玩家和他们的近邻共同负责维护他们共同的设施，他们会继续维护和种植，但如果所有玩家都负责维护整个农田的所有设施，玩家很可能会退出设施维护并停止栽培。然而，所有参与者之间的用水竞争比仅邻国之间的竞争更能促进耕作。因此，如果邻居而不是整个参与者负责维护他们的公共设施并共同合作，并且如果所有参与者而不是邻居的用水影响每个稻田的生产力，那么稻田景观是可持续的。他们继续维护和修炼，但如果所有玩家都负责维护整个农田的所有设施，玩家很可能会退出设施维护并停止修炼。然而，所有参与者之间的用水竞争比仅邻国之间的竞争更能促进耕作。因此，如果邻居而不是整个参与者负责维护他们的公共设施并共同合作，并且如果所有参与者而不是邻居的用水影响每个稻田的生产力，那么稻田景观是可持续的。他们继续维护和修炼，但如果所有玩家都负责维护整个农田的所有设施，玩家很可能会退出设施维护并停止修炼。然而，所有参与者之间的用水竞争比仅邻国之间的竞争更能促进耕作。因此，如果邻居而不是整个参与者负责维护他们的公共设施并共同合作，并且如果所有参与者而不是邻居的用水影响每个稻田的生产力，那么稻田景观是可持续的。促进种植多于邻居之间的竞争。因此，如果邻居而不是整个参与者负责维护他们的公共设施并共同合作，并且如果所有参与者而不是邻居的用水影响每个稻田的生产力，那么稻田景观是可持续的。促进种植多于邻居之间的竞争。因此，如果邻居而不是整个参与者负责维护他们的公共设施并共同合作，并且如果所有参与者而不是邻居的用水影响每个稻田的生产力，那么稻田景观是可持续的。