Population growth and growing demand for livestock products produce large amounts of manure,which can be harnessed to maintain soil sustainability and crop productivity.However,the impacts of excessive manure applicat...Population growth and growing demand for livestock products produce large amounts of manure,which can be harnessed to maintain soil sustainability and crop productivity.However,the impacts of excessive manure application on crop yields,nitrogen(N)-cycling processes and microorganisms remain unknown.Here,we explored the effects of 20-year of excessive rates(18 and 27 Mg ha^(–1)yr^(–1))of pig manure application on peanut crop yields,soil nutrient contents,N-cycling processes and the abundance of N-cycling microorganisms in an acidic Ultisol in summer and winter,compared with none and a regular rate(9 Mg ha^(–1)yr^(–1))of pig manure application.Long-term excessive pig manure application,especially at the high-rate,significantly increased soil nutrient contents,the abundance of N-cycling functional genes,potential nitrification and denitrification activity,while it had a weaker effect on peanut yield and plant biomass.Compared with manure application,seasonality had a much weaker effect on N-cycling gene abundance.Random forest analysis showed that available phosphorus(AP)content was the primary predictor for N-cycling gene abundance,with significant and positive associations with all tested N-cycling genes.Our study clearly illustrated that excessive manure application would increase N-cycling gene abundance and potential N loss with relatively weak promotion of crop yields,providing significant implications for sustainable agriculture in the acidic Ultisols.展开更多
The conversion of natural forests in subtropical regions to plantations or secondary forests has resulted in alterations in soil variables,microbial communities,and microbially mediated processes,including nitrous oxi...The conversion of natural forests in subtropical regions to plantations or secondary forests has resulted in alterations in soil variables,microbial communities,and microbially mediated processes,including nitrous oxide(N_(2)O)emissions.However,how forest conversion influences soil N_(2)O reduction and the abundance and community structure of N_(2)O-reducing microorganisms remains unclear.Here,we investigated the impact of converting natural forests to a secondary forest and Cunninghamia lanceolata and Pinus massoniana plantations on the abundance and community structure of N_(2)O-reducing microorganisms in both bulk soils and soil aggregates.Compared with the secondary forest,plantations had higher soil pH and available phosphorus and moisture contents,lower soil NH_(4)^(+)content,but similar aggregate sizes.Compared with the secondary forest,the conversion of natural forest to plantations resulted in significantly higher soil N_(2)O reduction rate and increased abundances of nosZⅠand nosZⅡgenes in bulk soils and soil aggregates.The abundance of nosZⅠwas higher than that of nosZⅡin all tested soils and had a stronger association with N_(2)O reduction rate,suggesting the greater role of nosZⅠ-carrying microorganisms in N_(2)O consumption.Forest conversion had a greater impact on the community composition of nosZ I than nosZⅡ,mainly by increasing the relative abundances of alpha-and beta-Proteobacteria,while decreasing gamma-Proteobacteria.However,nosZⅡ-carrying microorganisms were exclusively dominated by Gemmatimonadetes and less affected by forest conversion.Taken together,our findings significantly contribute to our understanding of the eco-physiological characteristics of N_(2)O-reducing microorganisms and highlight the importance of nosZⅠ-carrying microorganisms in N_(2)O consumption in subtropical forest soils.展开更多
基金supported by the National Natural Science Foundation of China(41930756 and 42077041)。
文摘Population growth and growing demand for livestock products produce large amounts of manure,which can be harnessed to maintain soil sustainability and crop productivity.However,the impacts of excessive manure application on crop yields,nitrogen(N)-cycling processes and microorganisms remain unknown.Here,we explored the effects of 20-year of excessive rates(18 and 27 Mg ha^(–1)yr^(–1))of pig manure application on peanut crop yields,soil nutrient contents,N-cycling processes and the abundance of N-cycling microorganisms in an acidic Ultisol in summer and winter,compared with none and a regular rate(9 Mg ha^(–1)yr^(–1))of pig manure application.Long-term excessive pig manure application,especially at the high-rate,significantly increased soil nutrient contents,the abundance of N-cycling functional genes,potential nitrification and denitrification activity,while it had a weaker effect on peanut yield and plant biomass.Compared with manure application,seasonality had a much weaker effect on N-cycling gene abundance.Random forest analysis showed that available phosphorus(AP)content was the primary predictor for N-cycling gene abundance,with significant and positive associations with all tested N-cycling genes.Our study clearly illustrated that excessive manure application would increase N-cycling gene abundance and potential N loss with relatively weak promotion of crop yields,providing significant implications for sustainable agriculture in the acidic Ultisols.
基金supported by the National Natural Science Foundation of China(Nos.41930756 and 42077041)Fujian Provincial Natural Science Foundation of China(No.2020J01187)。
文摘The conversion of natural forests in subtropical regions to plantations or secondary forests has resulted in alterations in soil variables,microbial communities,and microbially mediated processes,including nitrous oxide(N_(2)O)emissions.However,how forest conversion influences soil N_(2)O reduction and the abundance and community structure of N_(2)O-reducing microorganisms remains unclear.Here,we investigated the impact of converting natural forests to a secondary forest and Cunninghamia lanceolata and Pinus massoniana plantations on the abundance and community structure of N_(2)O-reducing microorganisms in both bulk soils and soil aggregates.Compared with the secondary forest,plantations had higher soil pH and available phosphorus and moisture contents,lower soil NH_(4)^(+)content,but similar aggregate sizes.Compared with the secondary forest,the conversion of natural forest to plantations resulted in significantly higher soil N_(2)O reduction rate and increased abundances of nosZⅠand nosZⅡgenes in bulk soils and soil aggregates.The abundance of nosZⅠwas higher than that of nosZⅡin all tested soils and had a stronger association with N_(2)O reduction rate,suggesting the greater role of nosZⅠ-carrying microorganisms in N_(2)O consumption.Forest conversion had a greater impact on the community composition of nosZ I than nosZⅡ,mainly by increasing the relative abundances of alpha-and beta-Proteobacteria,while decreasing gamma-Proteobacteria.However,nosZⅡ-carrying microorganisms were exclusively dominated by Gemmatimonadetes and less affected by forest conversion.Taken together,our findings significantly contribute to our understanding of the eco-physiological characteristics of N_(2)O-reducing microorganisms and highlight the importance of nosZⅠ-carrying microorganisms in N_(2)O consumption in subtropical forest soils.
