The effects of deforestation and land use/cover changes, i.e. Alnus subcordata and Cupressus sempervirens plantations, rice cultivation, and also deforested areas of Carpinus betulus-Parrotia persica on soil carbon (C) and nitrogen (N) fractions were evaluated in Hyrcanian region, northern Iran. Twelve samples per land use/cover were taken from the top 10 cm soil and characterized with respect to soil physico-chemical and biological properties. The fraction of C and N including microbial respiration (MR), microbial biomass C (MBC) and N (MBN), particulate organic matter C (POM-C) and N (POM-N), dissolved organic C (DOC) and N (DON), and N mineralization were measured. Land use/cover affected soil physico-chemical and biological properties. Higher values of MR were observed under Alnus (0.51 mg CO₂-C g soil⁻¹ day⁻¹) whereas the amount of MBC (711.73 mg kg⁻¹), POM-C (3.48 g kg⁻¹) and DOC (82.31 mg kg⁻¹) were significantly higher in Cupressus plantation. Soil N fractions (that is, mineralized N, MBN, POM-N, and DON) were significantly higher and lower under the Alnus and deforested areas (52.18–22.29 mg N kg soil⁻¹, 61.41–18.48 mg kg-¹, 0.49–0.22 g kg⁻¹, 33.23–13 mg kg⁻¹), respectively. In conclusion, plantations of A. subcordata and C. sempervirens increased the soil C and N fractions in deforested areas of northern Iran and are recommended for rehabilitation of degraded natural forests in the region.

毁林和土地利用/覆盖面积变化的影响，即Al木和Cu柏人工林，水稻种植以及甜菜Car（Carrotus betulus - Parrotia persica）的砍伐面积在伊朗北部Hyrcanian地区评估了土壤中碳（C）和氮（N）组分的含量。每个土地使用/覆盖范围的十二个样品是从最上层10 cm的土壤中采集的，并就土壤的理化和生物学特性进行了表征。C和N的比例包括微生物呼吸（MR），微生物生物量C（MBC）和N（MBN），颗粒有机物C（POM-C）和N（POM-N），溶解有机C（DOC）和N （DON）和N矿化被测量。土地利用/覆盖受影响的土壤的理化和生物学特性。在阿尔努斯（0.51 mg CO ₂ -C g土壤^-1天^-1）下观察到较高的MR值，而MBC（711.73 mg kg ^-1），POM-C（3.48 g kg ^-1））和DOC（82.31 mg kg ^-1）在柏树人工林中显着较高。土壤氮级分（即，矿化N，MBN，POM-N，和DON）为显著更高和下降低桤和砍伐区域（52.18-22.29毫克N-千克土壤^-1，61.41-18.48毫克公斤─ ¹，0.49mmol -0.22克千克^-1，33.23-13毫克千克^-1分别）。总之，种植园A. subcordata和C.杉在伊朗北部的毁林地区增加了土壤C和N分数，并建议在该地区退化天然林的恢复。