Bacterial Communities and Enzymatic Activities in Sediments of Long-Term Fish and Crab Aquaculture Ponds

Abstract

Aquaculture is among the most important and fastest growing agriculture sectors worldwide; however, it generates environmental impacts by introducing nutrient accumulations in ponds, which are possibly different and further result in complex biological processes in the sediments based on diverse farming practices. In this study, we investigated the effects of long-term farming practices of representative aquatic animals dominated by grass carp (GC, Ctenopharyngodon idella) or Chinese mitten crab (CMC, Eriocheir sinensis) on the bacterial community and enzyme activity of sediments from more than 15 years of aquaculture ponds, and the differences associated with sediment properties were explored in the two farming practices. Compared to CMC ponds, GC ponds had lower contents of TC, TN, and TP in sediments, and similar trends for sediment pH and moisture content. Sediment bacterial communities were significantly different between GC and CMC ponds, with higher bacterial richness and diversity in GC ponds. The bacterial communities among the pond sediments were closely associated with sediment pH, TC, and TN. Additionally, the results showed profoundly lower activities of β-1,4-glucosidase, leucine aminopeptidase, and phosphatase in the sediments of GC ponds than CMC ponds. Pearson’s correlation analysis further revealed strong positive correlations between the hydrolytic enzyme activities and nutrient concentrations among the aquaculture ponds, indicating microbial enzyme regulation response to sediment nutrient dynamics. Our study herein reveals that farming practices of fish and crab differently affect bacterial communities and enzymatic activities in pond sediments, suggesting nutrient-driven sediment biological processes in aquaculture ponds for different farming practices.

Microbial Community Structure and Its Driving Environmental Factors in Black Carp (Mylopharyngodon piceus) Aquaculture Pond

“…In the studied black carp polyculture ponds, the Shannon and Simpson diversity indices for aquatic bacteria increased during the mid-culture period (June, July, and August) in BP (p < 0.05), indicating that the bacterial diversity was in a dynamic succession process; the diversity decreased during the late culture period. The results were in accordance with those of a previous study [21], and the decreased species diversity in pond water may be due to the lesser nutrient availability in the late culture period.…”

“…As the main production mode, the traditional pond polyculture system is a common practice in aquaculture [20]. It was reported that the high nutrient accumulation and low transfer ratio of nutrient output in ponds caused diverse biological activities in the water and sediments [20][21][22]. The present study demonstrated dynamic changes in water microbial composition and the driving environmental factors during a culture period in black carp polyculture ponds, a popular aquaculture mode in South China.…”

Comparative analysis of bacterial communities in the sediment and seawater environments from marine large yellow croaker cages (Zhejiang coast, China)

“…Microbial communities play a pivotal role in energy and matter cycles in the sea, and the stability of the micro-ecological environment is a prerequisite for the aquaculture fish health (Olafsen, 2001;Vadstein et al, 2018). Previous studies mainly focused on the bacterial community compositions of aquaculture environments in pond ecosystems (Zhao et al, 2020;Zhang et al, 2021;Zeng et al, 2021). However, microbial communities in the open-oceanic mariculture ecosystems are understudied compared to the pond environment microorganisms.…”

Stochastic factors drive dynamics of ammonia-oxidizing archaeal and bacterial communities in aquaculture pond sediment

“…Indeed, the sediment could become highly reduced during the culture periods with the decomposition of organic matter, and cause significant effects on the nitrification process ( Dai et al, 2018 ). Although effects of environmental characteristics on microbial community variation have been found during disturbance ( Guggenheim et al, 2020 ; Monteiro et al, 2020 ), different responses of microbial communities to environmental change due to adaption has also been detected ( Dai et al, 2018 ; Xia et al, 2020 ; Zhang et al, 2021 ). In addition, research on agricultural cropland has indicated a significant influence of stochastic processes besides deterministic processes on bacterial community assembly ( Barnett et al, 2020 ).…”