Xie Xuefeng, Pu Lijie, Zhu Ming, Meadows Michael, Sun Licai, Wu Tao, Bu Xinguo, Xu Yan
College of Geography and Environmental Sciences, Zhejiang Normal University, Jinhua 321004, China; Key Laboratory of the Coastal Zone Exploitation and Protection, Ministry of Natural Resources, Nanjing 210023, China.
Key Laboratory of the Coastal Zone Exploitation and Protection, Ministry of Natural Resources, Nanjing 210023, China; School of Geography and Ocean Science, Nanjing University, Nanjing 210023, China.
Sci Total Environ. 2021 May 10;768:144996. doi: 10.1016/j.scitotenv.2021.144996. Epub 2021 Jan 8.
Reclamation of coastal land is increasingly being used as a means of raising agricultural productivity and improving food security in China. Applications of organic and inorganic supplements on reclaimed soils can significantly adjust a range of soil properties, C, N, P content and stoichiometry, and extracellular enzyme activities. However, the linkages between soil C꞉N꞉P stoichiometry and extracellular enzyme activities following reclamation of coastal saline soil remain largely unclear. In this experimental study, treatments included control (CK), chicken manure (OM), polyacrylamide plus chicken manure (PAM+OM), straw mulching plus chicken manure (SM + OM), buried straw plus chicken manure (BS + OM), and bio-organic manure plus chicken manure (BM + OM) were conducted to explore the linkages between soil physicochemical characteristics in reclaimed soils under different treatments and to evaluate their impact on oat yield. Soils under all reclamation treatments exhibited higher moisture content and, with the exception of SM + OM, lower soil pH compared to the control. The reclamation treatments also significantly decreased soil bulk density (BD) and soil salt content (SSC), and increased soil organic carbon (SOC), total nitrogen (TN) and organic phosphorus (OP). Our study of soil C꞉N꞉P stoichiometry revealed that newly reclaimed soils in the study area are N limited. Additionally, soil invertase (INV), urease (URE) and alkaline phosphatase (ALP) activity under different reclamation treatments were significantly enhanced compared with CK in surface soil, while soil catalase (CAT) activity was observed to be much higher in BM + OM than in other treatments. Mean oat yields for each of the treatments were ranked as follows: BM + OM > SM + OM > PAM + OM > BS + OM > OM > CK treatment. Our results also indicate that TN (12.1% and 12.4%) was the main factor affecting URE and ALP, whereas BD (13.5%) and pH (8.5) were key factors affecting INV and CAT activity, respectively.
在中国，围垦沿海土地越来越多地被用作提高农业生产力和改善粮食安全的一种手段。在垦殖土壤上施用有机和无机补充剂可以显著调节一系列土壤性质、碳、氮、磷含量和化学计量比以及细胞外酶活性。然而，沿海盐渍土开垦后土壤碳氮磷化学计量比与细胞外酶活性之间的联系仍不清楚。在本实验研究中，设置了对照（CK）、鸡粪（OM）、聚丙烯酰胺加鸡粪（PAM+OM）、秸秆覆盖加鸡粪（SM+OM）、埋秸秆加鸡粪（BS+OM）和生物有机肥加鸡粪（BM+OM）等处理，以探讨不同处理下垦殖土壤的土壤理化特性之间的联系，并评估它们对燕麦产量的影响。与对照相比，所有垦殖处理的土壤含水量均较高，除SM+OM外，土壤pH值较低。垦殖处理还显著降低了土壤容重（BD）和土壤盐分含量（SSC），增加了土壤有机碳（SOC）、总氮（TN）和有机磷（OP）。我们对土壤碳氮磷化学计量比的研究表明，研究区域新垦殖的土壤受氮限制。此外，与对照相比，不同垦殖处理下表层土壤的土壤转化酶（INV）、脲酶（URE）和碱性磷酸酶（ALP）活性显著增强，而在BM+OM处理中观察到土壤过氧化氢酶（CAT）活性远高于其他处理。各处理的燕麦平均产量排序如下：BM+OM＞SM+OM＞PAM+OM＞BS+OM＞OM＞CK处理。我们的结果还表明，TN（分别为12.1%和12.4%）是影响URE和ALP的主要因素，而BD（13.5%）和pH（8.5）分别是影响INV和CAT活性的关键因素。
