● Bridge constructions decreased soil bacterial alpha and beta diversity.
● Bridge constructions reduced soil microbial biomass carbon and nitrogen.
● Stochastic process dominates soil bacterial community assembly.
● Bridge constructions increased the relative importance of stochasticity.
Soils in mangrove ecosystems are home to diverse and unique microbes, which support many crucial ecosystem services. Despite their vulnerability, the impact of bridge construction on the soil microbiome in mangroves is poorly understood. This study assessed the bacterial community profiles and microbial biomass in mangrove soils under different bridge construction techniques: Sheet Pile Cofferdam (SP) and Steel Casing Pipe (SC), compared to the non-disturbed (ND) counterpart. Bridge construction significantly decreased the alpha diversity and caused biotic homogenization of soil bacterial communities, indicating a loss of microbial biodiversity due to human disturbance. Bridge construction also reduced the microbial biomass carbon and nitrogen. The assembly of soil bacterial communities was dominated by stochastic processes, and bridge construction increased the relative importance of stochasticity. However, the impacts on ecological networks varied with the construction technique, with SC soils showing higher network complexity and stability compared to the ND habitats. Changes in soil bacterial communities were primarily attributed to the shifts in soil pH and nutrient levels. This study identified the effects of sea-crossing bridge construction on the soil microbiome in mangrove ecosystems, aiding in careful planning and environmental impact assessments to minimize the negative effects of urbanization on mangrove ecosystems.
● In low-salinity soil, straw-returning did not change necromass contribution to SOC.
● In medium-salinity soil, straw-returning reduced necromass contribution to SOC.
● Straw-returning reduced POC contribution to SOC in low-salinity soil.
● Straw-returning increased POC contribution to SOC in medium-salinity soil.
● Salinity affects the contribution of microbial-derived and plant-derived C to SOC.
Salinization affects microbial-mediated soil organic carbon (SOC) dynamics. However, the mechanisms of SOC accumulation under agricultural management practices in salt-affected soils remain unclear. We investigated the relative contribution of microbial-derived and plant-derived C to SOC accumulation in coastal salt-affected soils under straw-returning, by determining microbial necromass biomarkers (amino sugars) and particulate organic C (POC). Results showed that, straw-returning increased necromass accumulation in low-salinity soil but did not change its contribution to SOC. In medium-salinity soil, straw-returning did not increase necromass accumulation but decreased its contribution to SOC. In low- and medium-salinity soils, the contribution of POC to SOC showed the opposite direction to that of the necromass. These results suggest that under straw-returning, the relative contribution of microbial-derived C to SOC decreased with increasing salinity, whereas the reverse was true for plant-derived C. Our results highlighted that straw-returning reduces the contribution of microbial anabolism to SOC accumulation in salt-affected soils with increasing salinity.
● Land use type affects the physicochemical properties of soil.
● The value of OM and TN is high in acacia soils.
● Strong acidity of soil is considered a serious constraint for agriculture.
● Suitable cash crops are acacia, cassava, banana, rice and maize.
Soil fertility is affected by land-use types and land management, which exacerbates soil erosion and various other forms of soil degradation in the mountainous regions of Vietnam. This study was conducted in A Luoi District, Thua Thien Hue, Vietnam to identify the effects of land-use types on specific soil physicochemical characteristics related to soil fertility. Soil physicochemical properties, such as organic matter (OM), total nitrogen (TN), total phosphorous (TP), and K+ were significantly affected by land-use type. The results showed that the soils were sandy in rice but clay loam for acacia and cassava. The mean bulk density value of acacia soil was significantly greater than that of other soils. TN were higher in the acacia soils than those in the rice, maize, and banana soils. The OM content was significantly higher in the acacia, cassava, and banana soils than those in the rice and maize soils. The mean of exchangeable K+ in the rice soil was higher compared to those in other soils and was affected by land-use type. The high exchangeable acidity content in the soils was probably due to intensive precipitation. However, both land use type and management did not affect the CEC value. Overall, the inappropriate land use caused the disturbance of soil physicochemical properties, indicating that the conditions of rice and maize soils are becoming worse than acacia soils. Therefore, lowering the intensity of cultivation, adopting incorporated soil fertility management, and applying organic fertilizer should preserve the existing conditions and enhance soil properties.
• Resource-conservation practices are emerging for attaining sustainability in agriculture.
• The research is now progressing towards combined application of emergent agronomic practices.
• Role of agro-climatic zones is imperative in developing compatible agronomic packages.
• Compatible agriculture packages may help in buffering the yield penalty occurred one system.
• Compatible agriculture packages would be the need for attaining true sustainability in agriculture.
Besides contributing majorly in the growth of a country, agriculture is one of the severely affected sectors at present. Several modifications and adaptations are being made in agricultural practices to cope-up with the declining soil fertility and changing climate scenarios across the world. However, the development and adoption of a single agricultural practice may not help in the holistic mitigation of the impacts of climate change and may result in economic vulnerability to farmers. Therefore, it is high time to develop and recommend a group of agricultural practices i.e. package-based agriculture system having some compatibility for one another in the long term. In this article, a viewpoint has been given on some emergent agronomic practices adopted in the tropical agro-ecosystems which have potential to be developed as compatible agricultural package in combination. Moreover, we also emphasized on exploring some key indicators/environmental factors to assess the compatibility of different agronomic practices. For identifying the research transition from single to combined agricultural practices, a bibliometric analysis was performed by using conservation agriculture (CA), the system of rice intensification (SRI), organic agriculture and soil (biochar) amendment as the major agronomic practices being used for improving agro-ecological services such as improving nutrient cycling, soil fertility and crop productivity as well as climate change mitigation. The results revealed that scientific communities are now paying attention to exploring the role of combined agricultural practices for agro-ecological balance and climate change adaptation. Moreover, the limitations of the adoption of agronomic packages under different agro-climatic zones have also been highlighted. The recommendations of the study would further help the environmental decision-makers to develop potential measures for climate change mitigation without compromising the agro-ecological balance.