the Collaborative Innovation for Juncao Ecology Industry（No. K80ND8002），the National Science Foundation of Fujian Province, China(No.2015J01154), and the Distinguished Young Scholars Foundation of the Higher Education Institutions of Fujian Province, China (No.JA13093)
土壤有机碳储量的准确估算对于研究全球碳“源/汇”动态变化至关重要，但目前使用大、中、小系列比例尺土壤数据库对我国亚热带土壤有机碳储量估算的影响并不清楚。基于此，选择位于亚热带地区的福建省作为研究区，系统分析1:5万、1:20万、1:50万、1:100万、1:400万、1:1 000万6种目前我国常用制图尺度土壤数据库对有机碳储量估算的影响。结果表明：6个制图尺度下表层土壤（0~20 cm）的有机碳储量为：552、637、573、573、614和549 Tg C；剖面土壤（0~100 cm）的有机碳储量为1 396、1 502、1 321、1 395、1 508和1 532 Tg C。不同土壤类型下受制图尺度影响最大的是粗骨土，表层和剖面的有机碳储量相对偏差分别达到88.75×104%和81.96×104%。不同行政区下表层和剖面受制图尺度影响最大的分别是厦门市和福州市，表层和剖面的有机碳储量相对偏差分别为26.44%和27.97%。 总体而言，制图尺度的不同将会对福建省土壤有机碳储量估算造成很大影响，这也进一步说明了亚热带地区选择适宜的制图尺度是十分必要的。
【Objective】Soil organic carbon (SOC) is an important part of the terrestrial carbon pool. Owing to its critical role in the global carbon cycle and its heavy storage in the terrestrial ecosystem, any slight change in the SOC pool would sure create certain influence on global climate. So, in order to simulate the global carbon cycle and design agricultural management measures, it is essential to estimate soil organic carbon storage (SOCS) accurately. Because of the spatial heterogeneity of soil properties, the study on SOC estimation on a regional scale may help improve accuracy of the estimation of SOC on the global scale, and moreover provide eco-environmental protection, regional decision-making and agricultural sustainable development with data support.【Method】In this study, based on the soil database of Fujian Province, and soil maps of the province, different in scale (1:50 000, 1:200 000, 1:500 000, 1:1 000 000, 1:4 000 000 and 1:10 000 000), SOCS were estimated for analysis of spatial distribution of SOC in the surface soil layer (0～20 cm) and soil profile (0～100 cm). The PKB method, i.e, pedological knowledge based method, was used to relate soil spatial data to soil attributes. As affected by the scale of a soil map, the number of soil patches decreased from 247 969 to 46 408, 15 282, 6 343, 440 and 345, with declining mapping scale and 3 082, 3 082, 2 718, 2 547, 1 000 and 890 soil profiles were made available for collection of soil physico-chemical properties, respectively. No doubt, the change in scale of soil mapping would sure bring about uncertainties in estimation of SOCS.【Result】Results show that based on the six soil maps different in mapping scale SOC in the surface soil layer (0~20cm) was estimated at 552, 637, 573, 573, 614 and 549 Tg C and in the soil profile (0~100 cm) at 1 396, 1 502, 1 321, 1 395, 1 508 and 1 532 Tg, respectively.. Estimation of SOC in skeleton soil, among all the types of soils, was most affected by mapping scale, with relative deviation in the surface soil layer and soil profile being 88.75×104% and 81.96 ×104%, respectively. However, the estimation of SOC density in the surface soil layer of red soil, the largest in land area, was, the lowest in relative deviation, being 4.28%, based on the soil map 1:1 000 000 in scale, while the estimation of SOC density in the soil profile was the lowest in relative deviation, being only 1.53%, based on the soil map, 1:500 000 in scale. The estimation of SOCS in Xiamen and Fuzhou, in terms of administrative region, were both affected by mapping scale, with relative deviation being 26.44% for topsoils and 27.97% for soil profiles, respectively. Relative deviations of the estimations of SOC density in the surface soil layer and profile in all the cities, except Xiamen, based on the soil map 1:500 000 in scale, were the lowest.【Conclusion】In general, regarding Fujian Province as a whole, the estimation of SOC density and storage in the surface soil layer and profile based on the soil map 1:1 000 000 in scale deviated the least from the currently available most detailed large-region data, 1:50 000 in scale, being 0.67% and 0.82% respectively, while that based on the soil map 1: 200 000 in scale did more, reaching 15.57% and 15.34% respectively. Estimation of SOCS in the surface soil layer and profile of Skeleton soil, among all the types of soils, was the most affected with relative deviation, reaching up to 88.75×104 % and 81.96 ×104%, respectively. The estimation of SOC density in the surface soil layer of red soil was the lowest in relative deviation, reaching 4.28% based on the soil map 1:1 000 000 scale and that in the soil profile of the red soil was, reaching 1.53% based on the soil map 1:500 000 in scale. The influence of mapping scale is also significant for Xiamen and Fuzhou. The relative deviation of the estimation of SOCS in the surface soil layer of Xiamen was 26.44%, and in the soil profile of Fuzhou was 27.97%. The relative deviations of the estimations of SOC density in both the surface soil layer and profile in all the cities, except Xiamen based on the soil map 1:500 000 in scale, were the lowest. All the findings in the study demonstrate that mapping scales does have certain influences on estimation of SOCS in the soils of the same area. In the case that administrators of an area do not have any accurate soil databases, it is advisable for them to estimate SOCS in their region and design agricultural management measures based on the soil map 1:500 000 in mapping scale.
陈中星,张 楠,张黎明,袁 平,姚彩燕,邢世和,邱龙霞,陈翰阅,范协裕.福建省土壤有机碳储量估算的尺度效应研究[J].土壤学报,2018,55(3):606-619. DOI:10.11766/trxb201708150359 CHEN Zhongxing, ZHANG Nan, ZHANG Liming, YUAN Ping, YAO Caiyan, XING Shihe, QIU Longxia, CHEN Hanyue, FAN Xieyu. Scale Effects of Estimation of Soil Organic Carbon Storage in Fujian Province, China[J]. Acta Pedologica Sinica,2018,55(3):606-619.复制