干旱冲击下草地租赁对草场退化及牧户生计的影响

近年来草地租赁市场在牧区出现并逐渐发展。然而,作为调节牧户资源的市场制度,其对草原社会生态的影响莫衷一是。Agent-based model(ABM)是社会科学领域先进的定量分析模型,可用来模拟复杂环境中主体间的交互关系及作用结果。本文首先在理论上分析了内蒙古牧区“人-草-畜”关系,揭示了牧区社会生态的复杂性,之后在此基础上,运用ABM模拟草地租赁中“人-草-畜”关系,通过调节干旱发生概率及牧户草地出租意愿,分析干旱冲击下草地租赁对草场退化及牧户生计的影响。为了更合理地展示和模拟牧区实际,本文结合2015—2016年内蒙古锡林郭勒盟、呼伦贝尔市的调研数据和部分文献、年报数据,对ABM中相关的参数进行设定,构建了用于模拟干旱冲击下牧区草地租赁的模型:①控制干旱概率,调节出租意愿的模型结果表明,在一定的干旱冲击下,草地租赁是一个有效的制度安排,可以缓解干旱导致的草地退化,提高牧区草场的总体生产力,并提高参与租赁户的生计水平。②控制出租意愿,调节干旱发生概率的模型结果则表明,当干旱加剧时,仅有单一的草地租赁制度无法阻止草场退化和牧户收入下降,草地生态及牧户收入仍然会受到干旱冲击的较大影响。因此,完善草地租赁市场,可在一定程度上缓解干旱冲击对草地退化的影响,提高牧户收入。但为了保障牧区社会生态的可持续性,还需发展牧业合作社和草地合作小组等其他制度。ABM可以通过对现实变量的参数化来模拟现实状况,对指导类似草原牧区等存在多个主体交互关系的社区实践具有重要作用。

The impact of grassland rental market on pasture deterioration and herders’livelihood under drought

Agent-based model(ABM)is an advanced quantitative analysis model in the field of social science,which can be used to simulate the interaction between subjects and their effects in complex environments.Recently,grassland rental market appeared and developed gradually in pastoral areas.However,as a market system regulating pastoral resources,its impact on grassland productivity is controversial.This paper first theoretically analyzed the human-grass-animal relationship in pastoral areas of Inner Mongolia and revealed the complexity of social ecology in pastoral areas.Then,on this basis,an ABM was used to simulate the human-grass-animal relationship in grassland rental market.In order to simulate the actual situation of pastoral areas,based on the investigation data of Xilin Gol League and Hulun Buir in Inner Mongolia from 2015 to 2016,as well as part of the literature and annual report data,we set the parameters involved in the ABM model,and built a model for simulating grassland rental market under the impact of drought.The results of the model controlling the probability of drought and adjusting the willingness to rent showed that under certain drought impact,grassland rental was an effective institutional arrangement,which could alleviate the grassland degradation caused by drought and improve the income of herders.The results of the model controlling the willingness to rent and adjusting the probability of occurrence of drought showed that when the drought intensified,grassland rental market could not prevent the degradation of grassland and the decline of herding income.Improving the grassland rental market can alleviate the impact of drought on grassland degradation and increase the income of herders.However,in order to ensure the sustainability of pasture areas,other systems such as animal husbandry cooperatives and grassland cooperation groups should be developed.ABM could simulate the real situation by parameterizing variables and could be adopted to guide the community practice with multiple subjects interacting with each other,such as grassland grazing areas.