湖北利川耕地土壤交换性钙镁含量及空间分布

Soil Exchangeable Calcium and Magnesium Content and Spatial Distribution of Cultivated Land in Lichuan, Hubei Province

摘要: 采集、检测、统计并分析了湖北省利川市338个耕地土样的交换性钙镁含量。结果表明，交换性钙点位均值2151 ± 1646 mg/kg，整体潜在缺乏，变幅96~9523 mg/kg，含量丰富以上超过1/4，潜在缺乏占近1/3，缺乏以下超过40%；交换性镁均值134 ± 75 mg/kg，极缺水平，变幅11~454 mg/kg，丰富水平不足1%，潜在缺乏近7%，缺乏以下超过92%。行政区域分布特征明显，交换性钙呈西北向东南逐渐降低的趋势；交换性镁东南角的毛坝镇最低，其它乡镇相当。水旱不同利用类型和海拔垂直分布差异较小，水田高于旱地，交换性钙镁水田均值分别为2351 mg/kg、154 mg/kg，旱地均值分别为2073 mg/kg、127 mg/kg；交换性钙低山 > 高山 > 二高山，都在2150 mg/kg上下；交换性镁二高山 > 低山 > 高山，在130 mg/kg左右。不同土类和母质发育的耕地交换性钙差异较大、交换性镁则较小，交换性钙棕壤 > 石灰土 > 水稻土 > 黄棕壤 > 潮土 > 紫色土 > 黄壤，交换性镁紫色土 > 石灰土 > 水稻土 > 黄棕壤 > 潮土 > 棕壤 > 黄壤；交换性钙河流冲积物 > 碳酸盐岩 > 第四纪黏土 > 紫色页岩 > 石英砂岩 > 泥质砂页岩，交换性镁紫色页岩 > 第四纪黏土 > 碳酸盐岩 > 河流冲积物 > 泥质砂页岩 > 石英砂岩。从统计学意义上看，交换性钙与交换性镁、pH、全氮、速效钾、有机质、有效铜、镉、砷呈极显著正相关，与有效硼呈显著正相关，与有效磷、有效铁呈极显著负相关；交换性镁与pH、有效硼、有效铜呈极显著正相关，与有效磷、有效铁、硒、汞呈极显著负相关，与铬呈显著负相关。

Abstract: The exchangeable calcium and magnesium content of 338 arable land samples in Lichuan City, Hubei Province was collected, tested, statistically and analyzed. The results show that the average point of exchangeable calcium is 2151 ± 1646 mg/kg, with an overall potential deficiency, with a variation of 96~9523 mg/kg, with rich content above 1/4, potential deficiency accounting for nearly 1/3, and lacking below 40%; the mean value of exchangeable magnesium is 134 ± 75 mg/kg. Extremely deficient level, variable range 11~454 mg/kg, rich level less than 1%, potential lack of nearly 7%, lack of more than 92%. The distribution characteristics of administrative areas are obvious, and the trend of exchange calcium is gradually decreasing from northwest to southeast; Maoba Town in the southeast corner of exchange magnesium is the lowest, and other townships are the same. Different utilization types and vertical distribution of water and drought are small. The paddy field is higher than the dryland. The average value of exchange calcium and magnesium paddy field is 2351 mg/kg and 154 mg/kg respectively, and the mean value of dryland is 2073 mg/kg and 127 mg/kg respectively. Exchangeable calcium low mountains > high mountains > two high mountains are all 2150 mg/kg up and down; exchangeable magnesium two high mountains > low mountains > high mountains, about 130 mg/kg. The exchange calcium of arable land developed by different soils and mothers is quite different, and the exchangeable magnesium is small. Exchangeable calcium brown soil > lime soil > rice soil > yellow brown soil > tide soil > purple soil > yellow soil, exchange magnesium purple soil > lime soil > rice soil > yellow brown soil > tidal soil > brown soil > yellow soil; exchange calcium river alluvial > carbonate Rock > Quaternary clay > purple shale > quartz sandstone > mud sand shale, exchangeable magnesium purple shale > Quaternary clay > carbonate > river alluvial > mud sand shale > quartz sandstone. In a statistical sense, exchangeable calcium is significantly positively correlated with exchangeable magnesium, pH, total nitrogen, quick-acting potassium, organic matter, effective copper, cadmium and arsenic, and significantly positively correlated with effective boron, and significantly negatively correlated with effective phosphorus and effective iron; exchangeable magnesium is significantly positively correlated with pH, effective boron and effective copper, and Phosphorus, effective iron, selenium and mercury are significantly negatively correlated, and significantly negatively correlated with chromium.