论文部分内容阅读
根据１９８３年至今１２年定位监测的结果，提出了一个描述典型草原在过大的牧压下退化和封育恢复演替的数学模型。建模的生态学公设是：１．植物群落占据的空间范围内环境因素视为均匀一致；２．退化和恢复演替进程中尚未发生植物种的消失和侵入；３．牲畜采食将增大牧草死亡率；４．草原群落内植物种群的竞争存在一个优胜顺序；５．植物种群增长遵循逻辑斯蒂克规律。对这一模型的稳定性分析说明：１．退化草原长期围封后可恢复到顶极状态；２．随着牧压的增强，草原群落将达到一个新的退化状态；３．退化过程和恢复过程的轨迹是不同的；４．草场改良措施改变了草原群落的演替轨迹和速率，使优质牧草在较大的种群尺度下向顶极状态演替。
Based on the results of 12 years of location monitoring from 1983 till now, a mathematical model describing the degradation of typical grasslands and the succession of enclosure and restoration under over-grazing pressure was proposed. Modeling the ecological public is: 1. The environmental factors within the space occupied by the plant community are considered as uniform; 2. The disappearance and invasion of plant species have not occurred in the process of degeneration and restoration succession; 3. Livestock feed will increase the mortality rate of forage grass; 4. There is a winning order in the competition of plant species in grassland communities. Plant population growth follows the logic of Logic. The stability analysis of this model shows: 1. Degraded grasslands can be restored to the climax after long-term enclosure; 2. As the pastoral pressure increases, the grassland community will reach a new state of degradation; 3. Degenerative and recovery trajectories are different; 4. Pasture improvement measures changed the succession trajectory and the rate of grassland community, so that the quality forage grass climax succession at the larger population scale.