禁牧对伊犁绢蒿种群数量特征及其构件生物量分配的影响

该研究于2020年5月、7月和9月在天山北坡中段试验区的禁牧区(5a)和放牧区分别进行调查采样，测定分析不同月份禁牧区和放牧区伊犁绢蒿种群数量特征(高度、盖度、密度和生物量)及构件(茎、叶、根)生物量，以揭示植物种群特征和构件生物量对禁牧的响应规律，为退化草地的修复治理以及合理利用提供依据。结果表明：(1)与放牧区相比，5月、7月、9月禁牧区的伊犁绢蒿种群的高度、盖度和生物量均显著增加(P<0.05),其中高度增幅为69.90%～95.53%,盖度增幅为186.53%～297.82%,生物量增幅为86.24%～631.83%。(2)随着月份的推移，禁牧区与放牧区伊犁绢蒿单株生物量、茎生物量和叶生物量均呈先降后增的变化趋势，而根生物量呈增加的趋势；禁牧改变了植株构件比例，与放牧区相比，禁牧区茎、叶的生物量所占单株生物量的比例在7月、9月均显著增加，而根生物量所占比例显著降低。研究认为，禁牧有利于地上植被的恢复，使其构件结构改变，是恢复退化荒漠草地植物的有效措施。

Effects of Grazing Exclusion on the Population Characteristics of Seriphidium transiliense and Its Component Biomass Allocation

The study was conducted in May, July and September 2020 in the grazing exclusion plots (5 a) and grazing plots of the experimental area in the middle part of the northern slope of Tianshan Mountains. The quantitative characteristics (height, cover, density and biomass) and component (stem, leaf and root) biomass of Seriphidium transiliense in the grazing exclusion plots and grazing plots in different months were measured and analyzed to reveal the characteristics of plant populations and component biomass in response to the grazing exclusion, and to provide a basis for the restoration and rational use of degraded grassland. The results showed that: (1) compared with the grazing plots, the height, coverage and biomass of S. transiliense in the grazing exclusion plots increased significantly (P<0.05) in May, July and September, with the increase in height ranging from 69.90% to 95.53%, the coverage ranging from 186.53% to 297.82% and biomass ranging from 86.24% to 631.83%, respectively. (2) As the months progressed, the single plant biomass, stem biomass and leaf biomass of S. transiliense showed decreasing and then increasing trend in both the grazing exclusion plots and grazing plots, while root biomass showed an increasing trend. The grazing exclusion changed the proportion of plant components, with the proportion of stem and leaf biomass to plant biomass increasing significantly in July and September, while the proportion of root biomass decreased significantly in the grazing exclusion plots compared to the grazing plots. The study concluded that grazing exclusion facilitates the recovery of above-ground vegetation, which changes its building block structure, and is an effective measure to restore vegetation in degraded desert grasslands.