Horizontal and vertical distributions of estuarine soil total organic carbon and total nitrogen under complex land surface characteristics

Abstract. Arctic field studies have indicated that the air temperature, soil moisture and vegetation at a site influence the quantity of snow accumulated, and that snow accumulation can alter growing-season soil moisture and vegetation. Climate change is predicted to bring about warmer air temperatures, greater snow accumulation and northward movements of the shrub and tree lines. Understanding the responses of northern environments to changes in snow and growing-season land surface characteristics requires: (1) insights into the present-day linkages between snow and growing-season land surface characteristics; and (2) the ability to continue to monitor these associations over time across the vast pan-Arctic. The objective of this study was therefore to examine the pan-Arctic (north of 60° N) linkages between two temporally distinct data products created from AMSR-E satellite passive microwave observations: GlobSnow snow water equivalent (SWE), and NTSG growing-season AMSR-E Land Parameters (air temperature, soil moisture and vegetation transmissivity). Due to the complex and interconnected nature of processes determining snow and growing-season land surface characteristics, these associations were analyzed using the modern nonparametric technique of alternating conditional expectations (ACE), as this approach does not impose a predefined analytic form. Findings indicate that regions with lower vegetation transmissivity (more biomass) at the start and end of the growing season tend to accumulate less snow at the start and end of the snow season, possibly due to interception and sublimation. Warmer air temperatures at the start and end of the growing season were associated with diminished snow accumulation at the start and end of the snow season. High latitude sites with warmer mean annual growing-season temperatures tended to accumulate more snow, probably due to the greater availability of water vapor for snow season precipitation at warmer locations. Regions with drier soils preceding snow onset tended to accumulate greater quantities of snow, likely because drier soils freeze faster and more thoroughly than wetter soils. Understanding and continuing to monitor these linkages at the regional scale using the ACE approach can allow insights to be gained into the complex response of Arctic ecosystems to climate-driven shifts in air temperature, vegetation, soil moisture and snow accumulation.

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Simulating the Effects of Land Surface Characteristics on Planetary Boundary Layer Parameters for a Modeled Landfalling Tropical Cyclone

Atmosphere ◽

10.3390/atmos13010138 ◽

2022 ◽

Vol 13 (1) ◽

pp. 138

Author(s):

Yu Wang ◽

Corene J. Matyas

Keyword(s):

Tropical Cyclone ◽

Land Surface ◽

Friction Velocity ◽

Inner Core ◽

Sensible Heat Flux ◽

Surface Characteristics ◽

Near Surface ◽

Land Surfaces ◽

Rain Rates ◽

Land Surface Characteristics

This study examined whether varying moisture availability and roughness length for the land surface under a simulated Tropical Cyclone (TC) could affect its production of precipitation. The TC moved over the heterogeneous land surface of the southeastern U.S. in the control simulation, while the other simulations featured homogeneous land surfaces that were wet rough, wet smooth, dry rough, and dry smooth. Results suggest that the near-surface atmosphere was modified by the changes to the land surface, where the wet cases have higher latent and lower sensible heat flux values, and rough cases exhibit higher values of friction velocity. The analysis of areal-averaged rain rates and the area receiving low and high rain rates shows that simulations having a moist land surface produce higher rain rates and larger areas of low rain rates in the TC’s inner core. The dry and rough land surfaces produced a higher coverage of high rain rates in the outer regions. Key differences among the simulations happened as the TC core moved over land, while the outer rainbands produced more rain when moving over the coastline. These findings support the assertion that the modifications of the land surface can influence precipitation production within a landfalling TC.

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INVESTIGATION OF INLAND POLLUTION USING TOTAL CARBON (TC), TOTAL ORGANIC CARBON (TOC), INORGANIC CARBON (IC), TOTAL NITROGEN (TN) AND TOC/TN RATIOS

Applied Ecology and Environmental Research ◽

10.15666/aeer/1706_1475114765 ◽

2019 ◽

Vol 17 (6) ◽

Author(s):

A R DINÇER

Keyword(s):

Organic Carbon ◽

Total Organic Carbon ◽

Total Nitrogen ◽

Inorganic Carbon ◽

Total Carbon

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One-step Oxidation of Total Organic Carbon, Total Nitrogen, and Total Phosphorous using Wet Chemical Oxidation

Journal of Korean Society of Environmental Engineers ◽

10.4491/ksee.2020.42.12.603 ◽

2020 ◽

Vol 42 (12) ◽

pp. 603-609

Author(s):

Jeong-Hwan Choi ◽

Dong-Hun Shin ◽

Hye-Bin Kim ◽

Jong-Gook Kim ◽

Kitae Baek

Keyword(s):

Organic Carbon ◽

Total Organic Carbon ◽

Total Nitrogen ◽

Uv Irradiation ◽

Oxidation Process ◽

Irradiation Time ◽

Suitable Condition ◽

Chemical Oxidation ◽

Total Phosphorous ◽

Wet Chemical

Objective:This study proposed the simultaneous multi-oxidation of total organic carbon, total nitrogen, and total phosphorous using modified wet chemical oxidation method.Methods:The multi oxidation process was based on the dual radical system with sulfate and hydroxyl radicals. The sodium persulfate (Na2S2O8) and sodium hydroxide (NaOH) were activated at 40℃ and UV irradiation with 254 nm to generate the sulfate radical and hydroxyl radical. The organic matters were oxidized by the dual radicals, and TOC, TN, and TP values were compared with the control group.Results and Discussion:The dual radical system oxidized organic carbon to carbon dioxide effectively, and the TOC values were similar to the value obtained from the high-temperature combustion technique. However, the residual persulfate after oxidation process interfered the absorbance for TN and inhibit the complexation in TP measurement. The residual persulfate was effectively converted to sulfate by longer heating and UV irradiation, and the interferences were more sensitive to reaction temperature than UV irradiation time. As a result, a higher temperature condition was more effective and enhanced the applicability of multi-oxidation.Conclusions:The multi oxidation of TOC, TN, and TP was demonstrated by wet chemical oxidation, and the proposed method is expected to secure the sample and reduce the analytic time. However, the more suitable condition to enhance the accuracy of TOC, TN, and TP in the multi-oxidation system should be studied further.

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