内蒙古草原草场放牧退化模式研究及退化监测专家系统雏议

 本文将定位研究与路线考察相结合，将放牧影响下草原的动态演替及其在牧压梯度上的空间变化相对比，研究了内蒙古主要草原草场的放牧退化模式，并在此基础上初步探讨了判别草场退化的数量指标和退化监测专家系统。1)植物种与牧压关系的分析，区别出放牧的定性和定量指示植物及宜中牧植物，并划分植物为不同的放牧生态种组。2)退化草原恢复过程的研究表明，根茎禾草的恢复快于丛生禾草；群落恢复过程是单稳态的，且恢复演替动态与其牧压梯度上的空间变化相对应。3)内蒙古高原主要草原草场在持续放牧影响下均趋同于冷蒿(Artemisia frigida)草原。冷蒿是最可靠的正定量放牧指示植物，但同时又是优良牧草和草原退化的阻击者。4)讨论了草原草场退化的概念，论述了草原逆向演替与草场退化的区别和联系，提出了区分草原的逆向演替为草场熟化和退化两个过程，并依草场群落与牧压的关系建立了判定草场是否退化及退化程度的数量指标。5)初步设计了草原草场退化监测—决策专家系统，包括监测、判别和决策三个步骤。

RESEARCH ON THE GRAZING DEGRADATION MODEL OF THE MAIN STEPPE RANGELANDS IN INNER MONGOLIA AND SOME CONSIDERATIONS FOR THE ESTABLISHMENT OF A COMPUT-ERIZED RANGELAND MONITORING SYSTEM

Grazing degradation trajectories of the main steppe rangelands in Inner Mongolia were studied by combining the experiments in the typical steppe area and the investigation in a large region. 1. The positive and negative,qualitative and quantitative grazing indicator species were distinguished; Species with preference to moderate grazing pressure were also recognized.2. Restoration of the degraded steppe rangeland demonstrated that the rhizomatic grass rehabilitated more quickly than tossuck grass; the restoration process was of monostable state; and the restoration dynamics corresponded generally to its spatial changes along a grazing gradient.3. The main steppe rangeland communities dominated by Stipa gobica, S. breviflora, S. krylovii, S. grandis, S. baicalensis and Aneurolepidium chinense will converge into Artemisia frigida community under sustaining grazing influence. A. frigida is the most effective quantitative indicator species of grazing pressure. It is also a fine forage species and an important species for resisting steppe degradation.4. The concept of steppe degradation was discussed. The difference and relations between steppe retrogression and rangeland degradation were analyzed. The grazing retrogression of steppes was divided into two successive stages, that is, rangeland utilization (improvement) and degradation. The quantitative critaria of rangeland degradation were established.5. A computerized monitoring and decision-making system of steppe rangelands was preliminarily discussed, including the three steps of monitoring, assessment and decision-making.