Effects of litter on soil organic carbon and microbial functional diversity

Chinese hickory (Carya cathayensis Sarg.) is a woody nut and oil tree from China. Intensive management including heavy application of chemical fertiliser and long-term application of herbicides has resulted in serious soil loss and degradation. This study aimed to test the hypothesis that intercropping in the soil under Chinese hickory stands may improve soil fertility and microbial community functional diversity. A field experiment consisting of four treatments (clean tillage; intercropping rape (Brassica rapa L.), ryegrass (Lolium perenne L.) or Chinese milk vetch (Astragalus sinicus L.) was conducted to study the effects of intercropping on soil organic carbon (SOC) structure and microbial community functional diversity under C. cathayensis stand, by means of 13C-nuclear magnetic resonance (NMR), and EcoPlates incubated at 25°C. After 4 years of treatment, intercropping increased available nitrogen (N), phosphorus and potassium in the soil by 25.1–54.2, 4.2–6.0 and 0–22.5 mg kg–1, respectively, relative to the clean tillage treatment; intercropping rape, ryegrass and Chinese milk vetch increased SOC, microbial biomass C (MBC), and water-soluble organic C (WOC) by 23.1–24.7, 138.6–159.7 and 56.2–69.5% (P < 0.05), respectively. The structure of SOC was also greatly changed by intercropping treatments. Intercropping increased carbonyl C by 29.9–36.9% (P < 0.05) and decreased alkyl C, O-alkyl C and aromatic C by 10.0–16.4, 18.9–20.9 and 10.5–16.6% (P < 0.05), respectively. Intercropping markedly improved microbial community functional diversity, which is characterised by increases in average well-colour development (AWCD), Shannon index and evenness index. Correlation analysis showed significant positive correlations among microbial biomass N, water-soluble organic N, SOC, WOC, MBC and AWCD (P < 0.05 or P < 0.01). The results demonstrate that sod cultivation is an effective soil management practice that improves soil quality and eliminates detrimental effects of clean tillage in Chinese hickory production.

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Environmental plantings’ influence on microbial attributes and soil properties in Australia.

10.5194/egusphere-egu21-1014 ◽

2021 ◽

Author(s):

Apsara Amarasinghe ◽

Oliver G G Knox ◽

Christine Fyfe ◽

Lisa A Lobry de Bruyn ◽

Brian R Wilson

Keyword(s):

Organic Carbon ◽

Microbial Activity ◽

Functional Diversity ◽

Nutrient Status ◽

Tree Age ◽

Ecosystem Functions ◽

Ecosystem Recovery ◽

Microbial Functional Diversity ◽

Soil P ◽

Remnant Vegetation

<p>Native trees and shrubs planted in large contiguous blocks (environmental plantings) have been established on agricultural lands in Australia to reinstate ecosystem functions and protect the biodiversity that has been degraded by agricultural activities. Limited work exists on the extent of the ecosystem recovery, but the assessment of microbial attributes (i.e. microbial activity and functional diversity) in these plantings may provide an indication of status. This study investigated how environmental plantings, and time since their establishment, affects aforementioned soil microbial attributes, &#160;to determine if the recovery to conditions found under extant remnant woodland were achievable. We compared changes in microbial functional diversity and activity along with total organic carbon (TOC), total nitrogen (TN), extractable phosphorous (P), soil pH, and electrical conductivity (EC) between environmental plantings established for 17 and 27 years, a paired adjacent pasture, and nearby remnant native woodland at Gunnedah, New South Wales. The results indicated that microbial activity under the trees, compared to that of pasture, increased by 20%&#8211;93% with increasing tree age. The ordination distance of microbial functional diversity declined between environmental plantings and remnant woodland as the age of the environmental planting increased, which was indicative of microbial functions becoming similar to that in the remnant vegetation with time. Soil P levels under trees were significantly higher compared to pasture and also increased with increasing planting age. However, TOC and TN levels under environmental plantings remained similar to pasture. These results suggest that microbial attributes and soil nutrient status of the investigated environmental plantings were on a trajectory of change from that of the pasture systems toward that of the remnant vegetation, but that full ecosystem recovery had not yet been achieved, even after 27 years.</p><p>Keywords: Environmental plantings, Microbial activity, Microbial functional diversity, Soil organic carbon, Soil nutrients</p>

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Soil organic carbon distribution drives microbial activity and functional diversity in particle and aggregate-size fractions

Pedobiologia ◽

10.1016/j.pedobi.2011.12.002 ◽

2012 ◽

Vol 55 (2) ◽

pp. 101-110 ◽

Cited By ~ 56

Author(s):

A. Lagomarsino ◽

S. Grego ◽

E. Kandeler

Keyword(s):

Organic Carbon ◽

Soil Organic Carbon ◽

Microbial Activity ◽

Functional Diversity ◽

Aggregate Size ◽

Carbon Distribution ◽

Size Fractions

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Soil Organic Carbon Content and Microbial Functional Diversity Were Lower in Monospecific Chinese Hickory Stands than in Natural Chinese Hickory–Broad-Leaved Mixed Forests

Forests ◽

10.3390/f10040357 ◽

2019 ◽

Vol 10 (4) ◽

pp. 357 ◽

Cited By ~ 9

Author(s):

Weifeng Wu ◽

Haiping Lin ◽

Weijun Fu ◽

Petri Penttinen ◽

Yongfu Li ◽

...

Keyword(s):

Carbon Source ◽

Organic Carbon ◽

Carbon Content ◽

Soil Carbon ◽

Functional Diversity ◽

Water Soluble ◽

Nuclear Magnetic Resonance Analysis ◽

Organic Carbon Content ◽

Microbial Functional Diversity ◽

13C Nuclear Magnetic Resonance

To assess the effects of long-term intensive management on soil carbon cycle and microbial functional diversity, we sampled soil in Chinese hickory (Carya cathayensis Sarg.) stands managed intensively for 5, 10, 15, and 20 years, and in reference Chinese hickory–broad-leaved mixed forest (NMF) stands. We analyzed soil total organic carbon (TOC), microbial biomass carbon (MBC), and water-soluble organic carbon (WSOC) contents, applied 13C-nuclear magnetic resonance analysis for structural analysis, and determined microbial carbon source usage. TOC, MBC, and WSOC contents and the MBC to TOC ratios were lower in the intensively managed stands than in the NMF stands. The organic carbon pool in the stands managed intensively for twenty years was more stable, indicating that the easily degraded compounds had been decomposed. Diversity and evenness in carbon source usage by the microbial communities were lower in the stands managed intensively for 15 and 20 years. Based on carbon source usage, the longer the management time, the less similar the samples from the monospecific Chinese hickory stands were with the NMF samples, indicating that the microbial community compositions became more different with increased management time. The results call for changes in the management of the hickory stands to increase the soil carbon content and restore microbial diversity.

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