摘要
基于样点代表性等级的土壤采样方法在成本、应用性、制图准确度上具有明显的优势,但在其他方面(如敏感性)上仍需要大量研究。为了进一步研究这种方法的可用性,本文以安徽宣城境内的丘陵山区为研究区,应用该方法分析以往土壤采样点的代表性等级,进而研究样点代表性等级对土壤制图准确度的影响。研究结果表明:①高等级代表性链广泛存在,而低等级代表性链则较少;②代表性链的等级有效地从不同程度反映出土壤形成环境的变异;③样点代表性采样设计的采样点与规则化网格采样、目的性采样有很大不同;④一般地,随着低等级样点的逐渐加入,制图准确度增加,但增幅随着样点等级的降低而降低。这些结果说明,样点代表性等级采样法在应用、成本、准确度几个方面都有明显的优点,因而具有较好的应用前景。需要注意的是,在应用该方法选择样点时,样点的代表性应达到一定级别,以避免制图准确度不会因为样点的加入而降低。此外,由于其他地形地貌类型(如平原区)还缺乏较好的土壤协同环境因子,该方法的应用受到了一定程度的限制。
The soil sampling method based on representativeness grades of sampling points has advantages at cost, applicability and mapping accuracy. However, it also needs to be researched, for example, sensitivity. In order to explore this method deeply, this study first used it to analyze representativeness grades of existing samples in a hilly area, and then studied relationships between representativeness grades of the samples and mapping accuracy. Results showed that： 1） representative environment chains with high representativeness grades existed widely, while chains with low grades were fewer, 2） representativeness grades of environment chains indicated variations of soil-forming environments in different degrees, 3） sampling results selected using this sampling method were much different from those using regular griding and purposive sampling methods, 4） mapping accuracy generally increased as more and more samples of lower representativeness grades were used for mapping, although the increases decreased during this process. These results illustrated that this sampling method is advantageous at application, cost and accuracy, and could be widely used. It is worth mentioning that taking samples of certain representativeness grade levels is necessary to avoid the decrease of mapping accuracy with more samples added for mapping. Besides, due to few good soil covariates in other topographic and geomorphological types, application of this method into such areas is limited to some extent.
出处
《土壤》
CAS
CSCD
北大核心
2014年第3期439-445,共7页
Soils
基金
广西大学科研基金项目(XBZ111320)资助
关键词
土壤制图
土壤采样
样点代表性
Soil mapping, Soil sampling, Representativeness grade
