1960－2010年广西红树林空间分布演变机制分析

Abstract

PDF HTML阅读 XML下载 导出引用 引用提醒 1960-2010年广西红树林空间分布演变机制 DOI: 10.5846/stxb201401160119 作者: 作者单位: 广西林业勘测设计院 南宁 530011,广西林业勘测设计院 南宁 530011 作者简介: 通讯作者: 中图分类号: 基金项目: 国家自然科学基金(41166001);中央财政林业科技推广示范资金(GXTG200904);UNEP-GEF-SCS-防城港红树林国际示范区 Mechanism analysis of temporal dynamics in mangrove spatial distribution in Guangxi, China: 1960-2010 Author: Affiliation: Guangxi Forest Inventory and Planning Institute Nanning 530011,China Fund Project: 摘要 | 图/表 | 访问统计 | 参考文献 | 相似文献 | 引证文献 | 资源附件 | 文章评论 摘要:为全面摸清1960-2010年广西红树林空间分布及其演变机制,采用多源遥感数据提取不同年度的红树林空间分布信息,分析了广西红树林空间分布动态特点,采用基于斑块的红树林空间演变机理分析方法,研究了1960/1976-2010年广西红树林空间演变机制。结果表明:1960/1976年、1990s年、2001年、2007年和2010年广西红树林斑块数量分别为1020、829、1094、1718个和1712个,面积分别为9062.5、7430.1、7015.4、6743.2、7054.3 hm2,近50年间红树林面积减少了22.16%,年均减少0.53%,斑块数量增加了67.8%;斑块平均面积由1960/1976年的8.9 hm2减小至2010年的4.1 hm2,大斑块数量显著减少,斑块破碎化严重;不同时期、不同区域和海湾,红树林面积和斑块数量的变化量、变化速率均不同;1960/1976年的斑块中,只有24个斑块至2010年时尚保持稳定,占2.4%,绝大部分斑块都发生了某种程度的变化。进一步分析结果表明:1960/1976-2010年,斑块消失(46.1%)、碎化(40.4%)、萎缩(13.5%)是面积减少的主要途径,新增(70.0%)和碎化(29.9%)是斑块数量增加的主要途径,但在不同时期,斑块数量和面积在各个途径上发生的变化量不尽相同;养殖塘和盐田建设(80.0%)、工程建设(10.9%)和围垦(9.1%)是面积净减少的驱动因子,自然过程(92.6%)和人工造林(7.4%)是斑块数量净增加的驱动因子,不同驱动因子在不同时期对斑块数量和面积变化的影响程度不同;斑块数量变化主要由自然过程作用下通过新增(39.6%)、消失(-9.1%)两个途径,以及养殖塘和盐田作用下通过消失(-15.3%)、碎化(14.5%)两个途径发生,斑块面积变化主要由自然过程影响下通过新增(17.5%)、扩张(12.6%)、消失(-6.1%),以及养殖塘和盐田建设驱动下通过斑块消失(-14.8%)、碎化(-13.9%)、萎缩(-6.6%)3个途径发生。 Abstract:Mangrove ecosystems are important for socioeconomic development and environmental protection but are experiencing sharp declines around the world. Asia has the most mangroves in area around the world but also has the largest human populations that threaten the ecosystem. Where mangrove is distributed and how its range changes are important topics for research throughout the world. Although many efforts have been made to study mangrove, more detailed information is still needed for better managing and protecting mangrove ecosystems. To analyze the mechanism of spatial dynamics of mangrove in Guangxi Beibu Gulf, China, from 1960 to 2010, multi-source remote sensing data were used to extract spatial information on mangroves in various years. The spatial distribution characteristics were analyzed and the spatial dynamic mechanisms of mangroves from 1960/1976 to 2010 were analyzed with a patch-based method. The results indicated that there were 1020, 829, 1094, 1718, and 1712 patches of mangrove in 1960/1976, 1990s, 2001, 2007, and 2010, respectively, and the areas were 9062.5, 7430.1, 7015.4, 6743.2, and 7054.3 hm2 in these 5 years, respectively. The region lost 22.16% of its mangrove area from 1960/1976 to 2010, with an annual loss rate of 0.53%. In the meantime, the patch-number increased 67.8%; the average patch-area decreased from 8.9 hm2 in 1960/1976 to 4.1 hm2 in 2010, and the number of big patches became smaller over time. Only 24 of 1020 patches (2.4%) in 1960/1976 remained unchanged till 2010, almost all the patches had changed to a certain degree. The results also indicated that lost (46.1%), fragmented (40.4%), and shrunken (13.5%) mangroves were the major components of the loss in mangrove area, whereas new (70.0%) and fragmented (29.9%) patches of mangrove were the main reasons for patch-number increases from 1960/1976 to 2010. The dynamics of patch-number and area changes varied both spatially and temporally. Shrimp and salt pond construction (80.0%), infrastructure construction (10.9%), and agriculture (9.1%) were the major causes of mangrove loss, and incensement of patch-number was due to natural processes (92.6%) such as extreme weather, flooding, sediment deposition, and growth/succession and plantations (7.4%) The causes of lost area varied both spatially and temporally. Changes in patch-number were mainly due to the natural processes and procedures of new patch (39.6%) and disappeared (-9.1%), and shrimp and salt pond construction and procedures of disappeared (-15.3%) and fragmented (14.5%); changes in mangrove areas were caused mainly by natural processes acted on the new (17.5%), expanded (12.6%), and disappeared (-6.1%) patches; shrimp and salt pond construction contributed to the disappeared (-14.8%), fragmented (-13.9%), and shrunken (-6.6%) mangrove patches. This study demonstrates the effectiveness of methodology that integrates natural processes and human activities into analysis of mangrove spatial distribution and its changes over time, and such a method can be used for in-depth mangrove research in other regions of the world. 参考文献 相似文献 引证文献