摘要
三江源生态保护和建设工程的实施对生态环境产生了积极的影响,草地是该地区最主要的生态系统类型,准确的草情诊断对该地区的生态稳定和畜牧业发展具重要意义,可更好的指导三江源区生态环境的保护和发展。基于长时间序列的遥感观测资料和野外采样数据,通过构建草情诊断基准值,结合草地覆盖度和产草量的变化率,根据加权求和计算出草情指数,诊断分析三江源生态工程实施后草地植被生长变化状况。结果表明:自2005年工程实施后,三江源自然保护区多年平均草情指数是3.47,草情状况较好,空间上呈现西南向东北方向变好的格局。草情状况极好、较好和中等的草地面积占比均显著高于草情极差和较差的草地面积占比。12年间草情指数变异系数为12.47%,草情年间变化呈现轻微波动。其中80.32%的草地草情状况无显著变化(P>0.05),14.61%的草情状况下降趋势显著,5.07%的草地草情状况上升趋势显著(P<0.05)。三江源国家公园的各园区的年均草情指数为黄河源园区(3.78)>长江源园区(3.61)>澜沧江源园区(3.15),草情状况较好。三个园区2/3以上的草地的草情无显著变化趋势;黄河源园区变化趋势显著变差的面积占比最高(17.74%),澜沧江源园区最低(13.49%);变化趋势显著变好的面积占比最高的为长江源园区(6.46%),最低的为澜沧江源园区(3.46%)。自生态保护工程实施后,草情呈现较好状况,但部分区域呈现下降的趋势,应继续加强三江源自然保护区草情状况的长期监测,进行合理的草情诊断,加大草情状况较差区域的生态保护。
The implementation of ecological protection and construction project has a positive impact on the ecological environment.Alpine grasslands are the main ecosystem type in the Three-River Headwaters Region,China.Accurately monitoring of the condition of grassland is important in guiding the ecological engineering construction and maintaining the balance of grassland ecosystem.Therefore,it is necessary to scientific evaluate the grassland condition.Based on the remote sensing and field sampling data,this paper firstly calculated the average grassland coverage and yield of 5 years before the implementation of the Eco-Project as the reference value of grassland condition,and then based on the weighted sum of grassland coverage and yield changes, the grassland condition index (GCI) was calculated to diagnose the growth status of grassland vegetation after the implementation of the Eco-Project. The results showed that the annual average GCI was 3.47 in the Three-River Headwater Region since the implementation of the Eco-Project. It had a good grassland condition, showing a pattern of getting better from southwest to northeast. The proportion of area with excellent, better and medium grass conditions was significantly higher than that with worse grass condition (P<0.05). The fluctuation of the GCI during 2005-2016 was relatively small, with a variation coefficient of 12.47%. 80.32% of the grassland showed no significant change (P>0.05), 14.61% showed a significant decline trend, and 5.07% showed a significant increase trend (P<0.05). The grassland in the Sanjiangyuan National Park was in good condition. The annual average GCI from high to low was the Yellow River Source Park (3.78), Yangtze River Source Park (3.61), and Lancang River Source Park (3.15). There was no significant change in the GCI of the grasslands above 2/3 in the three parks. The area with significant change in the GCI of the Yellow River Source Park had the highest proportion (17.74%), and the Lancang River Source Park had the lowest (13.49%). The highest percentage of GCI significantly improved area was the Yangtze River Source Park (6.46%), and the lowest was the Lancang River Source Park (3.46%). Since the implementation of the Eco-Protection, grassland has shown good conditions, but some areas have shown a downward trend. We should continue to strengthen the long-term monitoring of grassland condition in Sanjiangyuan Nature Reserve, conduct reasonable grassland condition diagnosis, and increase the ecological protection of areas with poor grass conditions.
作者
王穗子
张雅娴
樊江文
张海燕
WANG Suizi;ZHANG Yaxian;FAN Jiangwen;ZHANG Haiyan(Key Laboratory of Land Surface Pattern and Simulation,Institute of Geographical Sciences and Natural Resources Research,CAS,Beijing 100101,China;Institute of Qinghai-Tibetan Plateau,Southwest Minzu University,Chengdu 610041,China)
出处
《生态科学》
CSCD
2022年第1期100-109,共10页
Ecological Science
基金
第二次青藏高原综合科学考察研究项目(2019QZKK0608)
中国博士后科学基金资助项目(2020M670427)
国家重点研发计划项目(2017YFC0506505)。
关键词
草情指数
基准值
遥感
高寒草地
三江源
grassland condition index
reference value
remote sensing
alpine grassland
Three-River Headwaters Region
