Fan Fan, Liang Cunzhu, Tang Yongkang, Harker-Schuch Inez, Porter John R
College of Resource & Environmental Sciences; National Academy of Agriculture Green Development, China Agricultural University, Beijing 100193, China; Ministry of Education Key Laboratory of Ecology and Resource Use of the Mongolia Plateau & Inner Mongolia Key Laboratory of Grassland Ecology, School of Ecology and Environment, Inner Mongolia University, Hohhot 010021, China.
Ministry of Education Key Laboratory of Ecology and Resource Use of the Mongolia Plateau & Inner Mongolia Key Laboratory of Grassland Ecology, School of Ecology and Environment, Inner Mongolia University, Hohhot 010021, China.
Sci Total Environ. 2019 Jul 20;675:642-650. doi: 10.1016/j.scitotenv.2019.04.279. Epub 2019 Apr 19.
Grassland ecosystems are one of the most important terrestrial ecosystems in the world, producing essential both goods and ecosystem services (ES) for human beings. The Inner Mongolian steppe is a major grassland ecosystem in Northern China, covering 13.5% of the northern Chinese grassland area, and playing important ecological roles for the adjacent region of the capital Beijing-Tianjin-Hebei. Quantification of grassland ES under the different utilization patterns is vital for the maintenance of multiple ES and mitigation against ES loss in this region. We made a manipulative experiment with four grazing intensities (grazing exclusion, GE; light grazing intensity, LG; medium grazing intensity, MG; heavy grazing intensity, HG). We then quantified the intensities of eight different grassland ES (1. herbage intake, HT; 2. biodiversity conservation, BI; 3. soil nutrient retention, SN; 4 soil carbon stocks SC; 5. soil erosion prevention, SEP; 6. soil water storage, SWC; 7. potential nutrient recycling, PNC; 8. carbon sequestration from atmosphere. CS) and total ES via a series of field measurements. Pearson coefficients and trade-offs index were used to access the above ES relationships and degree of trade-offs between ES. Grazing intensities significantly (p < 0.05) affected the grassland intensities of 'regulating', 'culture' and 'provisioning' services, but the 'supporting' services. We found three types of relationships (trade-offs, synergy or neutral) have been found in this study. Trade-offs occurred between 'provisioning' and 'regulating' services. Although GE management presented significantly higher intensity of total ES (0.64) than LG (0.52), LG management significantly weakened the trade-offs between 'provisioning' and 'regulating' services (Trade-offs index 0.22) in comparison with GE (Trade-offs index 11.02). Our study suggests, therefore, that LG is the most suitable grassland utilization practice in the Inner Mongolian steppe.
草原生态系统是世界上最重要的陆地生态系统之一，为人类提供重要的产品和生态系统服务（ES）。内蒙古草原是中国北方的主要草原生态系统，占中国北方草原面积的13.5%，对京津冀相邻地区发挥着重要的生态作用。量化不同利用模式下的草原生态系统服务对于维持该地区的多种生态系统服务和减轻生态系统服务损失至关重要。我们进行了一项控制实验，设置了四种放牧强度（禁牧，GE；轻度放牧强度，LG；中度放牧强度，MG；重度放牧强度，HG）。然后，我们通过一系列实地测量，量化了八种不同草原生态系统服务的强度（1. 牧草摄入量，HT；2. 生物多样性保护，BI；3. 土壤养分保持，SN；4. 土壤碳储量，SC；5. 土壤侵蚀防治，SEP；6. 土壤储水，SWC；7. 潜在养分循环，PNC；8. 大气碳固存，CS）以及总生态系统服务。使用皮尔逊系数和权衡指数来评估上述生态系统服务之间的关系以及生态系统服务之间的权衡程度。放牧强度对“调节”、“文化”和“供给”服务的草原强度有显著影响（p<0.05），但对“支持”服务没有影响。我们在本研究中发现了三种类型的关系（权衡、协同或中性）。“供给”和“调节”服务之间存在权衡。尽管禁牧管理的总生态系统服务强度（0.64）显著高于轻度放牧（0.52），但与禁牧（权衡指数11.02）相比，轻度放牧管理显著削弱了“供给”和“调节”服务之间的权衡（权衡指数0.22）。因此，我们的研究表明，轻度放牧是内蒙古草原最合适的草原利用方式。
