东太湖围网全面拆除前后水生植被及水质变化

doi:10.19741/j.issn.1673-4831.2020.0986

摘要/Abstract

摘要： 针对东太湖围网拆除后水生植被及水质的变化，选择30 m分辨率的Landsat-8(OLI)数据作为数据源，对区域内水生植被进行监督分类，以现场水生植物调查数据作为水生植被分类评价依据，解译了围网拆除前后东太湖典型水生植被的变化，分析了2018—2020年主要水质指标及藻类生物量变化。研究表明，2019年底东太湖围网全面拆除后，2020年浮叶植物分布面积较2018年增加25.9%，挺水植物和沉水植物分布面积则分别减少11.8%和17.0%；沉水植物优势种由直立型种类转为冠层型种类，浮叶植物菱群丛、冠层型沉水植物金鱼藻群丛呈爆发式增长，生物量分别达6.84和9.90 kg·m^-2。2020年7—11月原围网区水体透明度仅为25.9 cm，较2018年同期显著下降，透明度下降不利于沉水植物生长，不利于东太湖草型清水态的维护；湖水叶绿素a和氨氮浓度显著上升，东太湖存在向藻型浑浊态转变的风险，应予重视。东太湖围网拆除后，湖泊生态系统变化较大，应加强湖泊生态研究和管理，人工辅助湖泊生态系统向草型清水态良性状态演替。

关键词: 水生植被, 水质, 遥感, 围网拆除, 东太湖

Abstract: In order to study the changes of aquatic vegetation and water quality after removal of pen aquaculture in Lake East Taihu, the landsat-8 (OLI) data with 30 m resolution was selected as the data source to perform the supervised classification of aquatic vegetation. In addition, the field survey data of aquatic plants, as the basis for the classified evaluation of aquatic vegetation, was used to interprete the changes of typical aquatic vegetation in Lake East Taihu before and after the removal of net-pen aquaculture, and to analyze the changes of main water quality indexes and algal biomass from 2018 to 2020. Results show that, after the net-pen aquaculture of Lake East Taihu being completely removed in the end of 2019, the distribution area of floating-leaf plants in 2020 increased by 25.9% compared with that in 2018, and the distribution area of emerged plants and submerged plants reduced by 11.8% and 17.0%, respectively. The dominant species of submerged plants changed from erect species to canopy species. The biomass of floating-leaf plant, Trapha maximowiczii, and the canopy submerged plant, Ceratophyllum demersum, increased explosively to 6.84 and 9.90 kg·m^-2, respectively. From July to November 2020, the water transparency in the former net-pen aquaculture area was only 25.9 cm, which decreased significantly compared with the same period in 2018. The decline of transparency is not conducive to the growth of submerged plants and the maintenance of macrophyte-dominated clear state. The concentrations of chlorophyll-a and ammonia nitrogen increased significantly, implying that there is a risk of transformation to algae-dominated turbidity state in Lake East Taihu. After the removal of pen aquaculture in Lake East Taihu, the lake ecosystem has changed greatly. Therefore, it is necessary to strengthen the ecological research and management of the lake, and artificially assist the lake ecosystem to succeed to the macrophyte-dominated clear state.

Key words: aquatic vegetation, water quality, remote sensing, removal of pen aquaculture, Lake East Taihu

中图分类号:

王友文, 徐杰, 李继影, 刘金娥. 东太湖围网全面拆除前后水生植被及水质变化[J]. 生态与农村环境学报, 2022, 38(1): 104-111.

WANG You-wen, XU Jie, LI Ji-ying, LIU Jin-e. Changes of Aquatic Vegetation and Water Quality after Removal of Pen Aquaculture in Lake East Taihu[J]. Journal of Ecology and Rural Environment, 2022, 38(1): 104-111.

参考文献

[1] YANG Qing-xin, LI Wen-chao, YU Lin, et al. Pen-fish-farming Development in East Taihu Lake and Its Effects on Lake Environment[J]. Journal of Lake Sciences, 1995, 7(3): 256-262. 杨清心, 李文朝, 俞林, 等. 东太湖围栏养殖及其环境效应[J]. 湖泊科学, 1995, 7(3): 256-262.
[2] BAN Xuan, YU Cheng, WEI Ke, et al. Analysis of Influence of Enclosure Aquaculture on Water Quality of Honghu Lake[J]. Environmental Science & Technology, 2010, 33(9): 125-129. 班璇, 余成, 魏珂, 等. 围网养殖对洪湖水质的影响分析[J]. 环境科学与技术, 2010, 33(9): 125-129.
[3] WU Qing-long, CHEN Kai-ning, HU Yao-hui, et al. Impacts of Pen Crab Farming on Evironment in East Taihu Lake[J]. Agro-environmental Protection, 2001, 20(6): 432-434, 442. 吴庆龙, 陈开宁, 胡耀辉, 等. 东太湖河蟹网围养殖的环境效应[J]. 农业环境保护, 2001, 20(6): 432-434, 442.
[4] HU Ting-ting, LIU Jin-song, DAI Xiao-lin, et al. Spatio-temporal Variation of Water Quality in Lake Luoma, Jiangsu Province, China[J]. Journal of Ecology and Rural Environment, 2016, 32(5): 794-801. 胡婷婷, 刘劲松, 戴小琳, 等. 骆马湖水质时空变化特征[J]. 生态与农村环境学报, 2016, 32(5): 794-801.
[5] WU Lin-kun, SUN Qiang, CAO Ping, et al. Effects of Floating Fence Ecological Grass Control Technology on Nitrogen and Phosphorus in East Taihu Lake[J]. Journal of Aquaculture, 2019, 40(10): 34-38. 吴林坤, 孙强, 曹萍, 等. 浮式围栏生态控草技术对东太湖水体中氮磷的影响[J]. 水产养殖, 2019, 40(10): 34-38.
[6] NASEEM S, BHAT S U, GANI A, et al. Perspectives on Utilization of Macrophytes as Feed Ingredient for Fish in Future Aquaculture[J]. Reviews in Aquaculture, 2021, 13(1): 282-300.
[7] ZHOU Lu-hong, GU Xiao-hong, ZENG Qing-fei, et al. Environmental Effects and Structural Optimization of Crab Culture in Ponds in Reclamation Zones of Gucheng Lake[J]. Journal of Ecology and Rural Environment, 2013, 29(1): 36-42. 周露洪, 谷孝鸿, 曾庆飞, 等. 固城湖围垦区池塘河蟹养殖环境影响及模式优化研究[J]. 生态与农村环境学报, 2013, 29(1): 36-42.
[8] LIU Bao-gui, TAN Guo-liang, XING Jiu-sheng, et al. Effect of Pen Culture on Community Structure of Planktonic Crustaceans in Lake Junshan[J]. Journal of Ecology and Rural Environment, 2015, 31(1): 82-87. 刘宝贵, 谭国良, 邢久生, 等. 围湖养殖对军山湖浮游甲壳动物群落结构的影响[J]. 生态与农村环境学报, 2015, 31(1): 82-87.
[9] CHEN He-sheng. Urgency for Protection of Water Environment in Eastern Taihu Lake[J]. Water Resources Protection, 2000, 16(3): 17-20, 45. 陈荷生. 东太湖水环境保护迫在眉睫[J]. 水资源保护, 2000, 16(3): 17-20, 45.
[10] ZHAO D, LV M, JIANG H, et al. Spatio-temporal Variability of Aquatic Vegetation in Taihu Lake over the Past 30 Years[J]. PLoS One, 2013, 8(6): e66365.
[11] LUO J H, LI X C, MA R H, et al. Applying Remote Sensing Techniques to Monitoring Seasonal and Interannual Changes of Aquatic Vegetation in Taihu Lake, China[J]. Ecological Indicators, 2016, 60: 503-513.
[12] LUO J H, DUAN H T, MA R H, et al. Mapping Species of Submerged Aquatic Vegetation with Multi-seasonal Satellite Images and Considering Life History Information[J]. International Journal of Applied Earth Observation and Geoinformation, 2017, 57: 154-165.
[13] SUN Tian-lin, ZHAO Yun-sheng, LIANG Ren-feng, et al. Study on the Reflected and Hyperspectral Mixed-pixel Character of Aquatic Plants and Water[J]. Spectroscopy and Spectral Analysis, 2012, 32(2): 449-452. 孙天琳, 赵云升, 梁壬凤, 等. 水生植物与水体混合像元的反射高光谱特征分析[J]. 光谱学与光谱分析, 2012, 32(2): 449-452.
[14] PU R L, BELL S, MEYER C, et al. Mapping and Assessing Seagrass along the Western Coast of Florida Using Landsat TM and EO-1 ALI/Hyperion Imagery[J]. Estuarine, Coastal and Shelf Science, 2012, 115: 234-245.
[15] XUE J R, SU B F. Significant Remote Sensing Vegetation Indices: A Review of Developments and Applications[J]. Journal of Sensors, 2017: 1-17. DOI: 10.1155/2017/1353691.
[16] ZHAO Kai. Pattern of Distribution and Change of Aquatic Plant in Taihu Lake[D]. Nanjing: Nanjing Normal University, 2017. 赵凯. 太湖水生植被分布格局及演变过程[D]. 南京: 南京师范大学, 2017.
[17] YU Cen-cen. Characteristics and Influencing Factors of Typical Odor Compounds Released by Macrophytes During Decomposition[D]. Nanjing: Nanjing Normal University, 2019. 余岑涔. 水生植物腐解释放嗅味物质的特征研究[D]. 南京: 南京师范大学, 2019.
[18] GU Xiao-hong, ZHANG Sheng-zhao, BAI Xiu-ling, et al. Evolution of Community Structure of Aquatic Macrophytes in East Taihu Lake and Its Wetlands[J]. Acta Ecologica Sinica, 2005, 25(7): 1541-1548. 谷孝鸿, 张圣照, 白秀玲, 等. 东太湖水生植物群落结构的演变及其沼泽化[J]. 生态学报, 2005, 25(7): 1541-1548.
[19] WU Qing-long, HU Yao-hui, LI Wen-chao, et al. Tendency of Swampiness of East Taihu Lake and Its Causes[J]. Acta Scientiae Circumstantiae, 2000, 20(3): 275-279. 吴庆龙, 胡耀辉, 李文朝, 等. 东太湖沼泽化发展趋势及驱动因素分析[J]. 环境科学学报, 2000, 20(3): 275-279.
[20] ZHANG Sheng-zhao, WANG Guo-xiang, PU Pei-min, et al. Succession of Hydrophytic Vegetation and Swampy Tendency in the East Taihu Lake[J]. Journal of Plant Resources and Environment, 1999, 8(2): 1-6. 张圣照, 王国祥, 濮培民, 等. 东太湖水生植被及其沼泽化趋势[J]. 植物资源与环境, 1999, 8(2): 1-6.
[21] XU De-rui, ZHOU Jie, ZHANG Jian-hua, et al. Status of Submerged Plants and Its Influencing Factors in East Lake Taihu[J]. Water Resources and Power, 2020, 38(4): 64-67, 94. 徐德瑞, 周杰, 张建华, 等. 东太湖沉水植物现状及影响因子分析[J]. 水电能源科学, 2020, 38(4): 64-67, 94.
[22] LIN Chuan, GONG Zhao-ning, ZHAO Wen-ji. The Extraction of Wetland Hydrophytes Types Based on Medium Resolution TM Data[J]. Acta Ecologica Sinica, 2010, 30(23): 6460-6469. 林川, 宫兆宁, 赵文吉. 基于中分辨率TM数据的湿地水生植被提取[J]. 生态学报, 2010, 30(23): 6460-6469.
[23] SONG B, PARK K. Detection of Aquatic Plants Using Multispectral UAV Imagery and Vegetation Index[J]. Remote Sensing, 2020, 12(3): 387. DOI: 10.3390/rs12030387.
[24] MOI D A, ALVES D C, ANTIQUEIRA P A P, et al. Ecosystem Shift from Submerged to Floating Plants Simplifying the Food Web in a Tropical Shallow Lake[J]. Ecosystems, 2021, 24(3): 628-639.