农业产业—资源系统耦合过程模型的构建与应用

发布时间：2018-04-10 00:29

  本文选题：农业产业-资源系统　切入点：链网结构　出处：《中国科学院大学(中国科学院教育部水土保持与生态环境研究中心)》2017年硕士论文

【摘要】：黄土丘陵区实施退耕还林还草工程以来成效显著,有效改善了生态环境,然而农业产业与资源的一致性较弱,林草资源量过剩,农业产业发展未建立在对农业资源有效利用的基础上,农业产业-资源系统发展处于相悖态势。为解决系统发展的相悖态势,协调农业产业系统和农业资源系统的关系,就要对农业产业-资源系统进行优化耦合,其关键在于弄清农业产业-资源系统的耦合过程和演变规律。基于农业产业与资源系统发展相悖的现实,对系统链网结构进行分析,明确系统链网循环路径演变规律,对系统链网结构进行表征,利用耦合过程模型从定量的角度阐明农业产业系统与农业资源系统的相互作用关系,判定农业产业-资源系统各阶段的耦合态势,并选取黄土高原丘陵区典型代表流域——县南沟流域进行实证分析,通过对不同优化情境下系统发展态势的分析,为系统结构优化提供依据,使得资源得到合理、高效利用,加速产业结构优化升级。主要结论有:1、黄土丘陵区农业产业-资源系统链网结构变化过程可以划分为四个阶段:Ⅰ.农业资源系统修复与结构调整阶段→Ⅱ.农业产业系统(结构)适应阶段→Ⅲ.农业产业-资源系统局部相悖阶段→Ⅳ.农业产业-资源系统优化耦合阶段。县南沟流域退耕工程实施以来,系统已经经历了第Ⅰ阶段(1999-2003年)、第Ⅱ阶段(2004-2010年)、第Ⅲ阶段(2011-),现处于第Ⅲ阶段。在这个过程中农业资源系统得以恢复重建,农业产业系统结构逐渐调整,经济效益逐年上升,然而农业产业系统与农业资源系统并未达到协调发展状态,目前林草资源丰富且未得到合理、有效利用,因此需要进一步优化农业产业-资源耦合系统结构,以促进区域可持续发展。同时,还可以得出:农业产业-资源系统链网结构可通过资源环境、农业资源、农业产业、经济效益予以表征。2、构建了县南沟流域农业产业-资源系统耦合过程模型。针对黄土丘陵区农业产业-资源系统演变轨迹发生变化的现实,参照农业生态经济系统耦合过程模型,建立农业产业-资源系统耦合过程模型:基础模型为dar(t)/dt=k1×ar(t)+k2×ai(t 和dai(t/dt=k_3 × ar(t)+ k_4 × ai(t);扩展模型为dar(t)/dt=k_1 ×(1 + e1)× ar(t)+ k_2 × ai(t)、dai(t)/dt = k_3×ar(t)+k4 ×(1 + e2)×ai(t)、(?)和(?)(?)(其中ar(t)、以ai(t)分别表示时间t时农业资源系统与农业产业系统总量,dar(t)/dt/dait、dai(t)/dt分别表示t时农业资源系统与农业产业系统的演化速度,k1、k2、k3、k4为影响系数,e1、e2分别为外力对农业资源系统与农业产业系统影响后导致其演变轨迹发生变化后的调整系数,xi(i=1,2,,,m)表示农业资源系统表征量,yj(j=1,2,,,n)表示农业产业系统表征量,pi、qj分别为对应的权重,△(pixi)、△(qiyi)分别为外力引起资源系统与产业系统偏离后的增量)。3、明确了耦合过程模型中参数k1、k2、k4的变化过程及其代表的生态经济意义。k值为正时,农业产业-资源系统状态对系统演化速度起促进作用,k值为负时,农业产业-资源系统状态对系统演化速度起抑制作用。基于农业资源系统发展角度而言,在k1、k2都为正的情境下,无论是农业产业的发展还是农业资源的建设,对农业资源系统的演化速度都起促进作用;在k_10、k_20的情境下,农业资源的开发利用对农业资源所依赖的环境以及农业资源的演变起促进作用,农业资源还有进一步增长的空间;在k10的情境下,农业资源发展的空间已经达到了极值,农业资源量趋于稳定。基于农业产业系统发展角度而言,在k40的情境下,农业产业的发展对农业产业系统的演化速度起促进作用,其中k30时农业产业发展建立在对农业资源的开发利用上,k30时农业资源支撑农业产业的发展较弱,农业产业系统的发展方向和规模需要进一步调整;在k40的情境下,农业产业的发展对农业产业系统演化速度起抑制作用。4、依据农业产业-资源系统耦合过程模型,对县南沟流域两种可能发展路径下的农业产业-资源系统耦合关系进行了预测。(1)融入碳汇产业情景:碳汇产业融入系统后,系数e2变化为正,增大了农业产业发展对农业产业系统演化速度的影响,可使资源系统演化速度提升2.56倍,(2)融入碳汇+ "轮牧+舍饲"养殖制度情境:系数e2变化为正且变化值更大,进一步增大了农业产业发展对农业产业系统演化速度的影响,可使资源系统演化速度提升4.66倍。5、以县南沟流域为案例的实证结果表明:退耕还林还草工程实施过程及方案有待于根据黄土丘陵区实际发展状况进行优化,促进碳汇产业的发展,使农业资源得到合理、高效利用,加速产业优化升级,实现农业产业-资源系统的良性耦合。
[Abstract]:In loess hilly area of returning farmland to forest and grassland has achieved remarkable results, effectively improve the ecological environment, but the weak consistency of agricultural industry and resources, forest resources surplus, agricultural industry development is not based on the effective utilization of agricultural resources, agricultural industry resources system development is contrary to solve the system development trend. The opposite situation, coordinate the relationship between the system of agricultural industrialization and agricultural resources system, to optimize the coupling of the agricultural industry resources system, the key is to clarify the coupling process of the agricultural industry resources system and the evolution law. Agricultural industry and resources development system based on the reality of conflict, the system chain network structure analysis, clear the system chain cycle path evolution, to characterize the system chain network structure, using the coupled model to elucidate the process system of agricultural industrialization and agricultural resources from the quantitative point of view The interaction between the system, determine the coupling situation of each stage of the agricultural industry resources system, and select the typical hilly area of the Loess Plateau Watershed -- Empirical Analysis of Xiannangou watershed, analyzes the development situation of different optimization context system, provide the basis for system optimization, making efficient use of the resources reasonably, accelerate. The optimization and upgrading of industrial structure. The main conclusions are: 1, changes in resource system chain network structure of agricultural industry in loess hilly region can be divided into four stages: 1. Agricultural resources system repair and adjustment of the structure, phase II. The agricultural industry system (structure) to adapt to phase III. The agricultural industry resources system and the local counter IV. Optimize the coupling stage of agricultural industry resources system. Since the Xiannangou watershed restoration project implementation, the system has experienced the first stage (1999-2003 years), the second stage (2004-2010 Year), stage III (2011-), is now in the stage. In the process of agricultural resources system reconstruction, agricultural industry structure adjustment system gradually, the economic benefit increased year by year, but the system of agricultural industrialization and agricultural resources system did not reach the state of coordinated development, the grass is rich in resources and did not get a reasonable, effective use therefore, we need to further optimize the agricultural industry resources system coupling structure, in order to promote the sustainable development of the region. At the same time, also can be drawn: the network structure of agricultural industry resources system through the chain of resources and environment, agricultural resources, agricultural industry, economic benefits to the characterization of.2, constructed the coupling process of Xiannangou watershed agricultural industry resources system model for agricultural resources industry in loess hilly region system evolution to change reality, according to the coupling process of agricultural eco economic system model, the establishment of agricultural industry resources 绯荤粺鑰﹀悎杩囩▼妯″瀷:鍩虹��妯″瀷涓篸ar(t)/dt=k1脳ar(t)+k2脳ai(t 鍜宒ai(t/dt=k_3 脳 ar(t)+ k_4 脳 ai(t);鎵╁睍妯″瀷涓篸ar(t)/dt=k_1 脳(1 + e1)脳 ar(t)+ k_2 脳 ai(t),dai(t)/dt = k_3脳ar(t)+k4 脳(1 + e2)脳ai(t),(?)鍜，

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