Abstract
Anthropogenic nitrogen (N) addition has increased soil nutrient availability, thereby affecting ecosystem processes and functions in N-limited ecosystems. Long-term N addition decreases plant biodiversity, but the effects of short-term N addition on soil microbial community is poorly understood. The present study examined the impacts of short-term N addition (NH4NO3) on these factors in a sandy grassland and semi-fixed sandy land in the Horqin Sandy Land. We measured the responses of soil microbial biomass C and N; on soil β-1,4-glucosidase (BG) and β-1,4-N-acetylglucosaminidase (NAG) activity; and soil microflora characteristics to N additions gradient with 0 (control), 5 (N5), 10 (N10), and 15 (N15) g N m-2 yr-1. The soil microbial biomass indices, NAG activity, and soil microflora characteristics did not differ significantly among the N levels, and there was no difference at the two sites. The competition for N between plants and soil microbes was not eliminated by short-term N addition due to the low soil nutrient and moisture contents, and the relationships among the original soil microbes did not change. However, N addition increased BG activity in the N5 and N10 additions in the sandy grassland, and in the N5, N10, and N15 additions in the semi-fixed sandy land. This may be due to increased accumulation and fixation of plant litter into soils in response to N addition, leading to increased microbial demand for a C source and increased soil BG activity. Future research should explore the relationships between soil microbial community and N addition at the two sites.
Highlights
Nitrogen (N) is the major growth-limiting elements for plant growth in most terrestrial ecosystems, especially in arid and semi-arid ecosystems [1,2]
In the semi-fixed sandy land, N addition significantly decreased soil microbial biomass carbon (SMBC) and SMBN compared with the control (P < 0.05, Table 2), but with no significant differences among N addition levels (P > 0.05)
This study analyzed the responses of soil microbial characteristics to short-term N addition in the sandy grassland and semi-fixed sandy land of the Horqin sandy land
Summary
Nitrogen (N) is the major growth-limiting elements for plant growth in most terrestrial ecosystems, especially in arid and semi-arid ecosystems [1,2]. Changing N availability is an important component of the functions of terrestrial ecosystems, under global climate change scenarios [3,4]. During the 20th century, humans have more than doubled the amount of N added to the biosphere [5]. Soil microbial community responses to short-term nitrogen addition in China’s Horqin Sandy Land number PRJNA615072. Other relevant data are within the paper and its Supporting Information files. Control N5 N10 N15 SMBC (mg kg-1) 32.24 ±2.60Ab 17.16 ±2.59Aa 16.32 ±4.37Aa 16.81 ±4.45Aa 13.48 ±1.97Aa SMBN
Sign-in/Register to view highlights & summary Sign-in/Register to access full text options 
Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have
Schedule a callDisclaimer: All third-party content on this website/platform is and will remain the property of their respective owners and is provided on "as is" basis without any warranties, express or implied. Use of third-party content does not indicate any affiliation, sponsorship with or endorsement by them. Any references to third-party content is to identify the corresponding services and shall be considered fair use under The CopyrightLaw.
