Effect Of Mineral Fertilizers On Pinus Massoniana Leaf Litter Decomposition In Taizi Mountains

In Masson pine?Pinus massoniana?forest ecosystem at Taizishan forest national park,litterfall is the major source of organic carbon?OC?that will form humus elements and organic cover.Masson's pine forest plays an important role in forestry production and forest ecosystem in China.The response of Masson's pine leaf litter decomposition to mineral fertilizers were investigated in Taizishan forest national park,in Hubei province to test the following hypotheses:?1?nutrients addition would accelerate litter decomposition process at Masson's pine forest,?2?nutrients addition would increase amino acids concentration,?3?nutrients addition would change microbial biomass,and microbial community,?4?nutrients addition would effect on soil enzyme activity and soil nutrients.In this study,Masson's pine leaf litter was studied using the litterbag technique.Four treatment was conducted at the following levels:control no addition mineral fertilizers,N?CO?NH₂?₂?46.4%,?,NP?CO?NH₂?₂?46.4%plus P₂O?12%,?,and NPK?CO?NH₂?₂?46.4%plus P₂O?12 plus K₂O?51%?.The main results are:1. Masson's pine leaf litter decomposition significantly affected by mineral fertilizer,in which the decomposition rate was orderly NPK>NP>N>CK.2. Amino acid concentration significantly affected by the type of mineral fertilizers and all sampling stages,but only released at 180 days and 270days.3. Microbial biomass?MBC,MBP,and MBN?has increased at all sampling times and NPK>NP>N>CK.The relative abundance of fungal was over the year decreased,and the at 180 days orderly NPK>NP>N>CK.4. The change of soil enzyme activity varied on different treatments and different sampling orderly NPK>NP>N>CK,while total potassium,total phosphorus,and organic matter decreased which ordered NPK>NP>N>CK.In addition,the ratio of C/P,and N/P has increased over the year,which the content of C/P,and N/P were respectively CK>N>NP>NPK,only C/N has decreased,and the decreased content of C/N were orderly CK>N>NP>NPK.