Soil moisture and soil-litter mixing effects on surface litter decomposition: A controlled environment assessment

Litter decomposition is a fundamental path for nutrient cycling in a natural ecosystem. However, it remains unclear how species diversity, including richness and evenness, affects the decomposition dynamics in the context of grassland degradation. Using a litter bag technique, we investigated the litter-mixing effects of two coexisting dominant species (Leymus chinensis Lc and Phragmites australis Pa), as monocultures and mixtures with evenness (Lc:Pa) from M1 (30:70%), M2 (50:50%), and M3 (70:30%), on decomposition processes over time (60 and 365 days). The litter bags were placed on the soil surface along a degradation gradient [near pristine (NP), lightly degraded (LD), and highly degraded (HD)]. We found that 1) mass loss in mixture compositions was significantly and positively correlated with initial nitrogen (N) and cellulose contents; 2) litter mixing (richness and evenness) influenced decomposition dynamics individually and in interaction with the incubation days and the degradation gradients; 3) in a general linear model (GLM), nonadditive antagonistic effects were more prominent than additive or neutral effects in final litter and nutrients except for carbon (C); and 4) in nutrients (C, N, lignin) and C/N ratio, additive effects shifted to nonadditive with incubation time. We speculated that the occurrence of nonadditive positive or negative effects varied with litter and nutrients mass remaining in each degraded gradient under the mechanism of initial litter quality of monoculture species, soil properties of experimental sites, and incubation time. Our study has important implications for grassland improvement and protection by considering species biodiversity richness, as well as species evenness.

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Modelling the effect of soil moisture and organic matter degradation on biogenic NO emissions from soils in Sahel rangeland (Mali)

Biogeosciences Discussions ◽

10.5194/bgd-12-1155-2015 ◽

2015 ◽

Vol 12 (2) ◽

pp. 1155-1203

Author(s):

C. Delon ◽

E. Mougin ◽

D. Serça ◽

M. Grippa ◽

P. Hiernaux ◽

...

Keyword(s):

Soil Moisture ◽

Litter Decomposition ◽

Litter Production ◽

No Production ◽

Emission Model ◽

No Emission ◽

Yearly Average ◽

No Release ◽

Emission Fluxes ◽

Sahel Region

Abstract. This work is an attempt to provide seasonal variation of biogenic NO emission fluxes in a sahelian rangeland in Mali (Agoufou, 15.34° N, 1.48° W) for years 2004–2008. Indeed, NO is one of the most important precursor for tropospheric ozone, and the contribution of the Sahel region in emitting NO is no more considered as negligible. The link between NO production in the soil and NO release to the atmosphere is investigated in this study, by taking into account vegetation litter production and degradation, microbial processes in the soil, emission fluxes, and environmental variables influencing these processes, using a coupled vegetation-litter decomposition-emission model. This model includes the Sahelian-Transpiration-Evaporation-Productivity (STEP) model for the simulation of herbaceous, tree leaf and fecal masses, the GENDEC model (GENeral DEComposition) for the simulation of the buried litter decomposition and microbial dynamics, and the NO emission model (NOFlux) for the simulation of the NO release to the atmosphere. Physical parameters (soil moisture and temperature, wind speed, sand percentage) which affect substrate diffusion and oxygen supply in the soil and influence the microbial activity, and biogeochemical parameters (pH and fertilization rate related to N content) are necessary to simulate the NO flux. The reliability of the simulated parameters is checked, in order to assess the robustness of the simulated NO flux. Simulated yearly average of NO flux ranges from 0.66 to 0.96 kg(N) ha-1 yr-1, and wet season average ranges from 1.06 to 1.73 kg(N) ha-1 yr-1. These results are in the same order as previous measurements made in several sites where the vegetation and the soil are comparable to the ones in Agoufou. This coupled vegetation-litter decomposition-emission model could be generalized at the scale of the Sahel region, and provide information where little data is available.

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Litter mixing effect on decomposition rate and nutrient release: low quality leaves of coastal species

10.22541/au.162626116.63018882/v2 ◽

2021 ◽

Author(s):

Lili Wei

Keyword(s):

Litter Decomposition ◽

Decomposition Rate ◽

Nutrient Release ◽

Additive Effect ◽

Nutrient Concentrations ◽

Mangrove Species ◽

Litter Bag ◽

Litter Mixtures ◽

Coastal Species ◽

Litter Mixing

Coastal wetlands are among the most carbon-rich ecosystems in the world. Litter decomposition is a major process controlling soil carbon input. Litter mixing has shown a non-additive effect on the litter decomposition of terrestrial plants particularly of those species having contrasting litter quality. But the non-additive effect has been rarely tested in coastal plants which generally having low-quality litters. We selected three common mangrove species and one saltmarsh species, co-occurring in subtropical coasts, to test whether the non-additive effect occurs when the litters of these coastal species mixing together. We are also concerned whether the changes in the decomposition rate of litter will affect the nutrient contents in waters. A litter-bag experiment was carried out in a glasshouse with single and mixed leaf litters. A non-additive effect was observed in the litter mixtures of mangrove species Aegiceras corniculatum vs. Kandelia obovata (antagonistic) and A. corniculatum vs. Avicennia marina (synergistic). Whereas, the mixture of A. corniculatum (mangrove species) and Spartina alterniflora (saltmarsh species) showed an additive effect. The strength of the non-additive effect was unrelated to the initial trait dissimilarity of litters. Instead, the decomposition rate and mass remaining of litter mixtures were strongly related to the carbon concentrations in litters. Nutrient content in waters was dependent on the decomposition rate of litter mixtures but not on the initial nutrient concentrations in litters. Despite the behind mechanisms were not yet revealed by the current study, these findings have improved our understanding of the litter decomposition of coastal species and the consequent nutrient release.

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Sunlight and Soil–Litter Mixing: Drivers of Litter Decomposition in Drylands

Progress in Botany ◽

10.1007/978-3-319-08807-5_11 ◽

2014 ◽

pp. 273-302 ◽

Cited By ~ 23

Author(s):

Paul W. Barnes ◽

Heather L. Throop ◽

Steven R. Archer ◽

David D. Breshears ◽

Rebecca L. McCulley ◽

...

Keyword(s):

Litter Decomposition ◽

Litter Mixing

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Long-term responses of leaf litter decomposition to temperature, litter quality and litter mixing in plateau wetlands

Freshwater Biology ◽

10.1111/fwb.12860 ◽

2016 ◽

Vol 62 (1) ◽

pp. 178-190 ◽

Cited By ~ 17

Author(s):

Guodong Liu ◽

Jinfang Sun ◽

Kun Tian ◽

Derong Xiao ◽

Xingzhong Yuan

Keyword(s):

Leaf Litter ◽

Litter Decomposition ◽

Litter Quality ◽

Leaf Litter Decomposition ◽

Litter Mixing ◽

Plateau Wetlands

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Effects of litter mixing on litter decomposition and soil properties along simulated invasion gradients of non-native trees

Plant and Soil ◽

10.1007/s11104-019-04160-4 ◽

2019 ◽

Vol 442 (1-2) ◽

pp. 79-96 ◽

Cited By ~ 1

Author(s):

Pilar Castro-Díez ◽

Álvaro Alonso ◽

Alberto Romero-Blanco

Keyword(s):

Soil Properties ◽

Litter Decomposition ◽

Native Trees ◽

Litter Mixing

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Propanil Plus Methyl Parathion on Rice (Oryza sativa)

Weed Science ◽

10.1017/s004317450007497x ◽

1988 ◽

Vol 36 (3) ◽

pp. 335-339 ◽

Cited By ~ 3

Author(s):

Gene D. Wills ◽

Joe E. Street

Keyword(s):

Oryza Sativa ◽

Soil Moisture ◽

Environmental Conditions ◽

Methyl Parathion ◽

Field Experiments ◽

Controlled Environment ◽

Planting Dates ◽

Effects Of Temperature ◽

Effect On Yield ◽

Wilting Point

Effects of propanil [N-(3,4-dichlorophenyl)propanamide] applied to three- to four-leaf rice (Oryza sativaL.) 1 or 7 days before, after, or tank mixed with methyl parathion (O,O-dimethyl-O-4-nitrophenyl phosphorothioate) were determined under different environmental conditions. Field experiments determined the effect on yield of drill-seeded rice, ‘Labelle’ for two planting dates in 1982 and ‘Lemont’ for one planting date in 1986. Treatments were applied at sunrise and at noon. Growth chamber and greenhouse experiments determined the effects of temperature, relative humidity (RH), and soil moisture on response of Labelle rice. In all experiments, propanil, both alone and with methyl parathion, resulted in 20 to 30% leaf burn during the first week after treatment with rapid recovery to less than 10% injury after 3 to 4 weeks. In field experiments, yields were not reduced in the treated rice below that in the untreated controls. In controlled-environment experiments, rice was not injured by propanil plus methyl parathion more than by propanil alone after 2 to 4 weeks. Both treated and untreated rice were injured more by the environmental conditions of high (40 C) temperature, low (40%) RH, and low (near the wilting point) soil moisture than by low (30 C) temperature, high (100%) RH, and flooded soil.

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