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Background: The changes in land use patterns may provide immediate economic advantages, but they also lead to significant disruptions in ecosystem services. These modifications have the potential to adversely impact water supply, air quality, disaster response, carbon storage, and biodiversity. Therefore, these modifications affect the provision of ecosystem services and have a negative effect on human well-being. Hence, it is crucial to investigate how land use changes affect carbon storage to enhance ecosystem services, lessen the consequences of climate change, advance human welfare, and direct effective land management practices. Methods: Min River Basin (MRB) is a significant water reservoir in China, providing valuable ecosystem services. Currently, the MRB is undergoing significant alterations in the land use due to country’s policy changes. Therefore, this study analyzed alterations in land use, dynamics of the alterations, and transfer matrix in MRB. The alterations in these indices were recorded for three time periods, i.e., 2000, 2010, and 2020. Furthermore, the influence of land use changes on carbon storage was investigated by InVEST (Integrated Valuation of Ecosystem Services and Tradeoffs) model. Results: The main land use classes in the MRB consisted of forest land, grassland, and arable land, and most of the alterations were recorded among these three classes. The arable land was declined by 163–333 km2, while grassland reduced by 23–233 km2 from 2000 to 2020. Likewise, forest land witnessed a decrease of 34–167 km2 from 2000 to 2020. The dominant land use dynamics consisted of construction land and water areas, whereas the entire land use dynamics exhibit a consistent increasing trend. Moreover, carbon storage witnessed a significant decrease during the study period due to the reduction in forest land, grassland, and arable land. Conclusion: The land use patterns in the MRB have witnessed substantial transformations because of recent policy implementations. Land use changes from forest land, arable land and grassland to other types exerted significant influence on carbon storage. Generally, carbon storage decreased from 2000 to 2020. The decline in carbon storage in the MRB is mostly attributed to urban growth, and construction activities. Therefore, these activities should be carefully monitored to improve carbon storage in the basin.

ABSTRACT: The purpose of this experiment was to determine the effectiveness of compound feed additive (CFA) to replace antibiotics for broiler production. A total of 350 one-day-old Arbor Acres broilers were randomly divided into 7 groups, 5 replications in each group and 10 broilers in each replication. Group A was the control; group B was supplemented with 75 mg/kg chlortetracycline; groups C, D, and E were supplemented with 0.03, 0.06, and 0.09% CFA including glucose oxidase, curcumin, and Lactobacillus acidophilus; group F was supplemented with 0.03% CFA plus 0.50% glucose; group G was supplemented with 0.50% glucose. The feeding period was divided into the early (1–21 d) and later stages (22–42 d). The results showed that average daily gain (ADG) and feed conversion rate (F/G) in group F in later stage were significantly better than those in the control and antibiotic groups; the diarrhea rates in the groups containing CFA in both stages was significantly lower than that in the control and antibiotic groups, indicating that CFA was better than antibiotics to improve growth and decrease diarrhea rate for broilers. Pathogenic E. coli challenge significantly increased diarrhea rates and decreased ADG for broilers; however, CFA addition could alleviate the above negative responses by increasing gut Lactobacillus abundance and decreasing Shigella abundance. It can be concluded that CFA can replace antibiotics to regulate intestinal microbiota, reduce diarrhea rate, and improve broiler growth.

Energy flux is a key component and driving factor in ecosystem processes and functions. Using 2015 datasets of eddy covariance, vegetation and meteorological measurements at four dominant ecosystems on the Mongolian Plateau, we analyzed the inter-site and seasonal variations and underlying biophysical controls on energy balance and partitioning in a meadow steppe (MDW), typical steppe (TPL), dry typical steppe (DRT) and shrubland (SHB). Vegetation dynamics dominated the energy partitioning. The growing season (May-Sept) net radiation (Rn) was 20% less at SHB due to higher bare soil coverage area than that at MDW. High vegetation cover and soil water content resulted in the highest latent heat (LE) at MDW, while sparse vegetation showed the highest sensible heat (H) at DRT among the four vegetation types. The Bowen ratios (β, H/LE) at TPL (1.68), DRT (1.44) and SHB (1.44) were an order of magnitude higher than that at MDW (0.14). At DRT and SHB, β had significantly negative feedback on canopy conductance (p

Land reclamation and grassland management are important land utilization pattern for effective use and restoration of alkali-saline land in agriculture-pasture transition regions. These large-scale land cover/land use changes (LCLUC) could impose profound and divergent impacts on terrestrial carbon (C) and H2O cycling, hence require precise assessment of ecosystem CO2 uptake and water use differences due to specific land use of the same climate/soil landscape. We initiated clustered eddy covariance flux-tower observations and C/H2O fluxes analysis of 4 adjacent representative land cover and grassland managements types on alkali-saline Songnen Plain, including fenced meadow (as reference land use), clipped meadow, degraded alkali-saline land and paddy field in 2018–2019. Results showed that differences in land use influenced the magnitude and temporal variation of net ecosystem productivity (NEP) and evapotranspiration (ET). Compared to fenced meadow, paddy field increased growing season C uptake by 63.3% and ET by 35.4%, while degraded alkali-saline land and clipped meadow decreased C uptake by 43.0% and 30.6%, and ET by 32.1% and 3.2%. Degraded alkali-saline land barely sequestrate C in dry year, whereas paddy field is least sensitive to inter-annual precipitation variation. Growing season C uptake was advanced in clipped meadow due to increased surface temperature, while monthly ET peaked early at May in paddy field. Agricultural use and specific grassland management also caused large differences in ET partitioning. Fenced meadow had greater ET partitioned into transpiration (69%) than clipped meadow (58%), degraded alkali-saline land and paddy field (41% and 34%, respectively). Water use efficiency appeared greater in clipped meadow and degraded alkali-saline land than in fenced meadow, and responded differently to abiotic factors. Overall, large-scale LCLUC has exerted significant influence on terrestrial C/H2O balances and physical responses in alkali-saline Songnen Plain.

Different sizes of precipitation are specifically essential in controlling plant physiological processes in ecosystems and extremely important for predicting the effects of precipitation on arid and semiarid region carbon cycle. However, the sizes of precipitation events and their role in carbon flux processes remain unclear. A consecutive three years (2014–2016) eddy covariance flux measurements were conducted to investigate the changes in carbon fluxes under different sizes of precipitation in Mongolia – typical steppe (TPL), meadow steppe (MDW) and shrubland (SHB). Most of the precipitation distributions were dominated by small size events over all sites of the study area. Gross primary productivity reached highest on days with 2 mm d−1 and 5 mm d−1 of precipitation in 2015 and 2014, respectively in TPL, whereas the highest gross primary productivity observed at 10–25 mm d−1 precipitation size in both MDW and SHB. The ecosystem respiration changed positively with different sizes of precipitation events, except for the 5 mm d−1 and 10 mm d−1 precipitation size in the study sites. There existed positive relationship between net ecosystem CO2 exchange (NEE) and small size precipitation event in both TPL and MDW. The slight association was detected between NEE and small size precipitation (