家庭牧场模型模拟研究进展

Review of household ranch models

家庭牧场是草地资源利用的基本单元,其在生态恢复、多样性保护、农牧民经济收入提高等方面具有重要意义。家庭牧场中包含着环境、资源、经济、社会、管理等多层面的内容,是一个复杂系统,其研究正在朝着定量化、精细化、模式化、市场化的方向发展。模拟模型对于家庭牧场尺度上的复杂系统进行生产、经营、管理和研究是一个重要工具,其目的在于将限制牧场经营和发展的因素最小化,实现牧场效益的最优化。近年来,国内外出现了大量与家庭牧场相关的模型、软件,不仅用于模拟牧草生长、动物生长、温室气体排放等内容,同时还用于模拟相应的管理措施,其模拟结果用来研究家庭牧场复杂生态经济系统运行,指导该尺度上的生产经营决策。本文通过对国内外24个相关模拟模型的整理总结,从家庭牧场管理、牧草生长和温室气体排放等方面进行比较分析,提出了家庭牧场模拟模型发展的主要特点为:1)模拟模型在畜牧业发达国家发展迅速;2)农场模型的发展更为全面,尤其是奶牛和肉牛饲养农场模型更为系统;3)饲草平衡、能量平衡、效益最大化是模拟的主要目标;4)模型参数数量大且部分数据的获取较难;5)普适性和广域性模型缺乏。结合我国家庭牧场生产方式状况的区别,提出了ACIAR、Grass Gro和SEPATOU适用于以天然放牧为主的家庭牧场,而IFSM等模型较适合于集约化管理的牧场。综合考虑我国草地和家畜利用方式的现状,提出了我国家庭牧场模拟模型的建立和应用需着眼于已有研究和实践成果,跨学科、跨地域协作,最终实现我国家庭牧场模拟模型的快速发展。

Household ranch is a basic management unit and complicated production system critical for restoration of grassland ecosystem, conservation of biodiversity and improvement in incomes of farmers and herdsmen. While environment, natural resources,economy, society and management have been included in household ranch, the direction of future studies now includes the quantification, precision, stereotype and marketization of household ranch. Modeling has been important in the production,management and research in household ranch and in minimizing the factors restricting the management and development of household ranch and optimizing ranch benefits. Several various models and softwares have been developed in the past 20 years in relation to household ranch developement, and used in the simulation of grass growth, animal production, greenhouse gas emission and system management as well as in operating household ranch system and making management and policy decisions. The main characteristics of household ranch were summarized in this paper based on review of 24 models and comparison of four factors —household ranch production, management, herb growth and greenhouse gas emission. 1） There was a rapid development of models in the area of animal husbandry. 2） Farm models were more comprehensive than household ranch models, especially for dairy and beef farms. 3） The balances in forage, energy and benefit maximization were the basis of the simulations. 4） The model required a rangeof parameters, most of which were difficult to obtain. 5） There was lack of universal model with a wide scope of application. Based on production condition of household ranches in China, ACIAR, Grass Gro and SEPATOU models were fit for household ranches in natural grassland areas and IFSM model was good for intensive farm or enterprise systems. Depending on the current state of grassland and livestock production systems in China, it was necessary to base proven results of research and practice, and interdisciplinary and trans-regional co-operations for household ranch model building and application in China.