灰色GM(1,1)模型和Verhulst模型在喀斯特地区耕地预测中的应用——以毕节生态试验区为例

The application of Gray GM(1,1) model and Verhulst model in the forecast of farmland in the karst area——A case in Bijie ecological experimental area

毕节生态试验区是典型的喀斯特地区,人口密度大,生态环境脆弱,水土流失严重,耕地保护尤为重要。本文以毕节地区1998-2006年常用耕地面积统计数据为基础,分别利用灰色GM(1,1)模型和Verhulst模型对该喀斯特地区常用耕地面积变化作预测。预测结果表明,GM(1,1)模型和Verhulst模型都揭示了毕节地区常用耕地面积在未来几年呈逐年递减的趋势。但是通过模拟精度验证,研究区耕地面积原始数据变化曲线呈S型,就灰色GM(1,1)模型与Verhulst模型模拟预测结果相比较,对于原始数据的模拟,GM(1,1)模型预测精度较高,而Verhulst模型更适合研究区未来几年耕地面积变化的预测。该研究结果可为区域合理利用土地资源、编制土地利用规划和耕地保护提供依据。

As a typical karst area with a dense population and fragile ecological environment as well as serious soil erosion in Bijie ecological experimental area,the farmland protection is particularly important.Based on the statistic data of farmland from 1998 to 2006 in Bijie Region,this paper forecasts the changes of farmland in karst region with GM（1,1） model and the Verhulst model respectively.The forecast results show that both GM（1,1） model and the Verhulst model reveal the cultivated land in Bijie Region decreases gradually in the next years.However,by the NC verification of the model,the change of the original data of the cultivated land in the study area shows an S curve.To the imitation of the original data,the prediction results of the grey GM（1,1） are more accuracy than the Verhulst model,while the Verhulst is more suitable for the forecast of the changes in the coming years of the cultivated land in the study area.It can provide the basis for the rational use of land resources,the preparation of land-use planning and the protection of farmland.