Drivers for Carbon Variation of River in Three Gorges Reservoir Area

doi:10.11988/ckyyb.20230911

Abstract

Abstract:

Understanding the impact of land use and landscape patterns on river carbon cycling is crucial for improving the watershed environment. This study utilized the landscape index method, redundancy analysis (RDA), and Pearson correlation analysis to analyze the effects of landscape factors on river carbon cycling in the Three Gorges Reservoir area. The findings reveal that: 1) Within a buffer zone scale of 1 500 m, the land use and landscape patterns have a substantial impact on the concentration of dissolved carbon in water and the fluxes of CO₂ and CH₄ at the water-air interface. 2) The dissolved carbon within the 1 500 m buffer zone is influenced by several key variables, including built-up land, and forest land. For CO₂ and CH₄ fluxes at the water-air interface, influential variables include built-up land, forest land, grassland, arable land, bare land, Shannon’s diversity index (SHDI), and patch richness density (PRD).

Key words: land use, landscape index, greenhouse gases, dissolved inorganic carbon(DIC), dissolved organic carbon(DOC), buffer zones

CLC Number:

X522河流

CHENG Xue-jun, FU Chong-qing, XIAO Xiao, ZHANG Shuang-yin, XU Jian, ZHENG Hang, LIAO Mao-xin. Drivers for Carbon Variation of River in Three Gorges Reservoir Area[J]. Journal of Changjiang River Scientific Research Institute, 2024, 41(12): 66-72.

Figures/Tables 8

Fig.1 Distribution of monitoring points and layout of buffer zones

Table 1 Statistics of river carbon emissions and dissolvedcarbon concentrations

指标	CO₂/ (mmol·(m²·h)^-1)	CH₄/ (μmol·(m²·h)^-1)	DIC/ (mg·L^-1)	DOC/ (mg·L^-1)
最大值	4.179	33.550	46.024	29.941
最小值	-0.630	-36.287	25.988	3.847
均值	0.751	1.697	32.628	9.583
方差	1.752	148.904	17.469	31.301

Fig.2 Distribution of land use types in the study area

Fig.3 Proportions of land use types in buffer zones of different spatial scales

Fig.4 Distribution characteristics of landscape indices in buffer zones of different spatial scales

Table 2 Canonical axes eigenvalues and total explanatory variations of RDA for landscape features and carbon indicators

缓冲区半径/m	解释变量(景观特征)类型	排序轴	特征值	总解释变异/%	相关性
500	景观指数	1	0.321 7	62.02	0.859 7
500	景观指数	2	0.158 2		0.797 5
1 500	景观指数和土地利用	1	0.420 5	86.74	0.971 7
1 500	景观指数和土地利用	2	0.223 8		0.960 6
3 000	土地利用	1	0.249 3	44.55	0.779 5
3 000	土地利用	2	0.136 2		0.731 6

Fig.5 Sorting analysis of landscape features and carbon indicators within the 1 500 m buffer zone

Fig.6 Correlation between landscape features and carbon indicators within the 1 500 m buffer zone

[1]	YIN Ke, LIAO Si-yu. Spatio-temporal Variation and Prediction of Carbon Stocks in Chongqing Section of Three Gorges Reservoir Area Based on InVEST-PLUS Model [J]. Journal of Changjiang River Scientific Research Institute, 2024, 41(9): 60-69.
[2]	MENG Xin, LIU Jun, ZHANG Ju-mei, SU Yu-fan, YANG Jun-liang. Quantitative Evaluation of the Impact of Human Activities on Net Primary Productivity of Vegetation in Lüliang Mountains [J]. Journal of Changjiang River Scientific Research Institute, 2024, 41(11): 65-74.
[3]	WANG Yu, YE Chang-qing, ZHU Li-rong, LI Ang, LIANG Xu, ZOU Yi. Impact of Land Use Change on Ecosystem Service Function in Dongzhai Bay Area [J]. Journal of Changjiang River Scientific Research Institute, 2023, 40(8): 70-76.
[4]	XIE Xiang-dong, LIN Xiao-song, WANG Ying, TU Rong-yu, ZHANG Ji-xiang. Multi-scenario Simulation of Land Use in Nanchuan District of Chongqing Based on PLUS Model [J]. Journal of Changjiang River Scientific Research Institute, 2023, 40(6): 86-92.
[5]	ZHENG Ting-ting, CAI Hong, LIU Jia-wei. Effects of Land Use and Climate Change on Spatial Distribution of Hydrological Factors in Tongzi River Basin [J]. Journal of Changjiang River Scientific Research Institute, 2023, 40(5): 44-50.
[6]	SONG Hui-ling, CHEN Shu, AO Yuan-hong. Changing Characteristics of Blue and Green Water Resources in Hanjiang River Basin and Their Main Influencing Factors [J]. Journal of Changjiang River Scientific Research Institute, 2023, 40(4): 24-30.
[7]	PENG Hai-yue, REN yan, LI Qiong, WEI Jia-hua. Spatial and Temporal Land Use/Cover Change Characteristics of Qinghai-Tibet Plateau [J]. Journal of Changjiang River Scientific Research Institute, 2022, 39(8): 41-49.
[8]	TANG Jia, HU Xi-jun, WEI Bao-jing, LUO Zi-wei, ZHAO Si-wen, WANG Ye-zi. Land Use Change Prediction and Hydrological Response Assessment of Watershed Based on FLUS Model [J]. Journal of Changjiang River Scientific Research Institute, 2022, 39(4): 63-69.
[9]	ZHANG Gao-ling, XIE Hong-xia, SHENG Hao, ZHOU Qing, DUAN Liang-xia, WU Yan-yu. Erodibility of Red Soil in Subtropical Hilly Region in Response to Land Use Change [J]. Journal of Changjiang River Scientific Research Institute, 2022, 39(2): 63-69.
[10]	TONG Xiao-xia, WANG Jia-le, PU Jian, ZHANG Wen-jie, HUANG Jin-quan, XU Wen-sheng, WANG Zhi-gang. Response of Surface Water Quality to Vegetation Cover in Shenzhen City [J]. Journal of Changjiang River Scientific Research Institute, 2022, 39(11): 55-60.
[11]	BAI Shao-yun, MA Chen-yan, LIU Bin, LIU Yu-qing, ZHU Xiao-ning, YU Pei-heng. Land Use Cover Change in Qilu Lake Watershed Based on RS and GIS [J]. Journal of Changjiang River Scientific Research Institute, 2021, 38(4): 36-42.
[12]	BAI Shao-yun, LIU Bin, PAN Jia-wei, LIU Jia-min, CHEN Min, YU Pei-heng, CHEN Yi-yun. Analysing Ecological Land Use in Qilu Lake Basin Using Combined G1 Method and Variable Weight Theory [J]. Journal of Changjiang River Scientific Research Institute, 2021, 38(3): 45-50.
[13]	HUO Jun-jun, YI Ming-qi, WANG Jing, JIANG Yu-ji. Response of Runoff in Lhasa River Basin to Land Use and Climate Change [J]. Journal of Changjiang River Scientific Research Institute, 2021, 38(10): 33-39.
[14]	ZHANG Tao, LIU Yu-ting, YANG Xin-yue. Detectability of Hydrological Response to Land Use Change [J]. Journal of Changjiang River Scientific Research Institute, 2018, 35(8): 27-33.
[15]	GAO Yu-qin, WANG Huai-zhi, LU Xiao-hua, WANG Dong-dong, YUAN Yu. Simulation of Rainstorm Flood Response in Qinhuai River Drainage Basin under Land Use Cover Changes [J]. Journal of Changjiang River Scientific Research Institute, 2018, 35(6): 47-52,66.