Quantifying the vertical distribution pattern of land-use conversion in the loess hilly region of northern Shaanxi Province 1995–2015

Abstract Aquatic worms propagated in granular activated carbon (GAC) filter has become a troublesome problem for drinking water supply. This study investigated the vertical distribution patterns of naidids in GAC filter beds and assessed the effect of an additional sand bed, located below the GAC bed, in preventing naidids from being present in effluent. The results indicated that the vertical distribution data of naidids in the GAC filter bed were well fitted by a Gaussian distribution, and the location of peak population density was mainly affected by downward flow. Backwashing experiments revealed that additional pressure air scouring shifted the distribution pattern of naidids in the GAC filter bed, resulting in a significant enhancement in naidid removal efficiency. Additionally, the addition of a sand bed exhibited pronounced interception and inactivation effects on naidids, suggesting that it may be a very promising technology for preventing naidids propagated in GAC filters from being present in the effluent.

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The vertical distribution pattern of microbial- and plant-derived carbon in the rhizosphere in alpine coniferous forests

Rhizosphere ◽

10.1016/j.rhisph.2021.100436 ◽

2021 ◽

pp. 100436

Author(s):

Wentong Gao ◽

Qitong Wang ◽

Xiaomin Zhu ◽

Zhanfeng Liu ◽

Na Li ◽

...

Keyword(s):

Vertical Distribution ◽

Distribution Pattern ◽

Coniferous Forests ◽

Vertical Distribution Pattern ◽

The Vertical Distribution

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The Vertical Distribution Pattern of Microbial- and Plant-Derived Carbon in the Rhizosphere in Alpine Coniferous Forests

10.21203/rs.3.rs-525547/v1 ◽

2021 ◽

Author(s):

Wentong Gao ◽

Qitong Wang ◽

Xiaoming Zhu ◽

Zhanfeng Liu ◽

Na Li ◽

...

Keyword(s):

Vertical Distribution ◽

Distribution Pattern ◽

Soil Depth ◽

Dominant Role ◽

Mineral Soil ◽

Coniferous Forest ◽

Organic C ◽

Vertical Distribution Pattern ◽

Picea Asperata ◽

The Vertical Distribution

Abstract Background and aimsWhile the quantitative assessment of plant- and microbial-derived carbon (C) in the soil organic C (SOC) chemical composition in soil profiles has been initially explored, the vertical distribution pattern of these two C sources and their dominant role in SOC formation based on the insights related to the rhizosphere are still lacking.MethodsWe quantified the divergent accumulation of microbial-derived C (i.e., microbial residues), plant-derived C (i.e., lipids and lignin phenols) and SOC in the rhizosphere at various depths (0-10 cm, 10-20 cm and 20-30 cm) in the upper mineral soil and analyzed its control factors in an alpine coniferous forest (Picea asperata. Mast). We further revealed the relative contribution of plant- or microbial-derived C to rhizosphere SOC in the soil profile.ResultsThe contents of microbial- and plant-derived C and SOC in the rhizosphere decreased with soil depth and were mainly regulated by root and microbial biomass. Moreover, the contribution of microbial-derived C dominated by fungal residues to rhizosphere SOC at each soil depth (more than 62%) was much higher than that of plant-derived C (less than 6%), implying that the soil microbial C pump was intensely stimulated in the rhizosphere.ConclusionsThese results indicated that microbial-derived C was the main contributor of rhizosphere SOC at various depths in the upper mineral soil. Our findings provide direct experimental evidence for assessing the dominant contribution of microbial- or plant-derived C to SOC in the soil profile from the perspective of the rhizosphere.

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Seasonal differences in the vertical distribution pattern of Japanese jack mackerel, Trachurus japonicus: changes according to age?

ICES Journal of Marine Science ◽

10.1093/icesjms/fsp114 ◽

2009 ◽

Vol 66 (6) ◽

pp. 1289-1295 ◽

Cited By ~ 11

Author(s):

Takeshi Nakamura ◽

Akira Hamano

Keyword(s):

Vertical Distribution ◽

Distribution Pattern ◽

Artificial Reefs ◽

Clear Understanding ◽

Jack Mackerel ◽

Seasonal Differences ◽

Vertical Distribution Pattern ◽

Trachurus Japonicus ◽

Japanese Jack Mackerel ◽

The Vertical Distribution

Abstract Nakamura, T., and Hamano, A. 2009. Seasonal differences in the vertical distribution pattern of Japanese jack mackerel, Trachurus japonicus: changes according to age? – ICES Journal of Marine Science, 66: 1289–1295. The Japanese jack mackerel, Trachurus japonicus, is commercially and ecologically one of the most important fishery resources in Japanese waters. A clear understanding of the age-dependent, vertical distribution pattern is important for the effective and sustainable management of this resource. In this study, acoustic surveys were conducted from June to November 2001 in the western Sea of Japan to clarify seasonal differences. The survey area included a number of artificial reefs at depths >100 m. To identify fish species and determine the characteristics of the water column, simultaneous biological sampling and oceanographic surveys were carried out. The vertical distribution of Japanese jack mackerel varied with their age and size and between seasons. In June and July, aggregations of juvenile (age 0; <10 cm in length) Japanese jack mackerel were found in a layer between 20 and 50 m deep associated with a temperature range of 19–21°C. However, the age-0 aggregations were not observed from August to November. Conversely, the age-1+ schools aggregated around the artificial reefs when the temperature was <19°C. It is suggested that there are seasonal differences in the vertical distribution pattern between the early life and adult stages of Japanese jack mackerel. Because of the different vertical distributions of these life stages, acoustic backscatter information is useful for determining the age of the observed fish.

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