Comparative study on intensive use of rural residential land based on principal component analysis and entropy method

The choice of evaluation method of intensive land use determines the accuracy of evaluation results directly. Taking Shijiazhuang city as a case, this paper established the evaluation index system from four aspects—land use degree, land input intensity, output effect and sustainability, and then used principal component analysis (PCA) and entropy method to evaluate the use intensity of rural residential land in the year of 1999, 2005 and 2008. Finally, based on the above analysis, the two evaluation methods were compared. The results showed that: 1) The difference of intensity level of rural residential land derived from the two methods was almost within ±1, only the level difference of individual counties (cities) was within ±2. 2) The change rate of intensity, from 1999 to 2005, from 2005 to 2008 and from 1999 to 2008, showed the same trend by the two methods. The change rate of intensity calculated by entropy method was significantly higher than that calculated by PCA. 3) The spatial distributions of the intensity divided from the two methods presented a certain consistency, but also showed some differences simultaneously. The difference of evaluation results between the two methods were due to the difference of weight, the treatment difference of the results, the differences of the methods, theories and data standardization. Suggestions were proposed that if one or more time periods are involved in the intensity evaluation of rural residential land use, entropy method is more suitable, if it needs to evaluate the intensity of a given year, PCA method may be the better one.