Seasonal fluctuations of the nematode communities in a hop garden soil

AbstractA study on the seasonal fluctuation of nematode population was conducted during three vegetation periods (2005 – 2007), at 20 and 40 cm soil depth, from May to October, in a hop garden at Nemšová (Slovak Republic). The seasonal fluctuation of the nematode population was related to temperature and rainfall. At 20 cm soil depth of each year, the largest nematode population was recorded in July, and the smallest from July to October. At 40 cm soil depth, nematode abundance was not significantly different between the years 2006 and 2007. In general, at the same depth, a decrease of nematode abundance was observed from May to October. The soil nematode community was rich in bacteriovorous nematodes, especially in the top 20 cm soil. The genus Rhabditis was the eudominant taxon at both soil depths. This genus with the genera Cephalobus, Heterodera, Merlinius and Aglenchus represented the 50 % of the total nematode population at 20 cm soil depth and with the genera Cephalobus, Helicotylenchus, Heterodera and Merlinius represented the 52 % of total nematodes abundance at 40 cm depth.

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Soil nematode community changes associated with windfall and wildfire in forest soil at the High Tatras National Park, Slovak Republic

Helminthologia ◽

10.2478/s11687-009-0024-9 ◽

2009 ◽

Vol 46 (2) ◽

pp. 123-130 ◽

Cited By ~ 18

Author(s):

A. Čerevková ◽

M. Renčo

Keyword(s):

National Park ◽

Slovak Republic ◽

Trophic Group ◽

Forest Stand ◽

Soil Nematode ◽

Nematode Communities ◽

Soil Nematode Community ◽

Research Findings ◽

Community Changes ◽

The High Tatras

AbstractThe paper presents research findings on the influence of windfall and wildfire on nematode communities in Lariceto-Piceetum forest in the High Tatras in Slovakia. Comparison was made of an intact (REF), affected and extracted (EXT), non-extracted (NEX) and burnt (FIR) forest stand. A total of 55 species belonging to 36 genera were found. The EXT locality harboured the majority of the identified species, but the highest abundance of nematodes was observed in the FIR locality. Bacterial feeders were the dominant trophic group in all investigated plots. In the REF bacterial feeders were followed by root-fungal feeders, fungal feeders and omnivores, in the EXT by omnivores and plant parasites, in the FIR by omnivores and root-fungal feeders and in the NEX by fungal feeders and omnivores. The MI and SI were higher in the REF and the EXT compared to those in the FIR and the NEX, the highest B/F ratio was observed in the FIR and the highest EI was found in the REF. We can conclude that disturbance of forest vegetation and soil has had a clear and demonstrable impact on nematode communities.

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Seasonal Stabilities of Soil Nematode Communities and Their Relationships with Environmental Factors in Different Temperate Forest Types on the Chinese Loess Plateau

Forests ◽

10.3390/f12020246 ◽

2021 ◽

Vol 12 (2) ◽

pp. 246

Author(s):

Na Huo ◽

Shiwei Zhao ◽

Jinghua Huang ◽

Dezhou Geng ◽

Nan Wang ◽

...

Keyword(s):

Food Web ◽

Loess Plateau ◽

Soil Nematode ◽

Soil Food Web ◽

Food Web Structure ◽

Nematode Communities ◽

Web Structure ◽

Soil Nematode Community ◽

Nematode Abundance ◽

Soil Nematode Communities

The bottom-up effects of vegetation have been documented to be strong drivers of the soil food web structure and functioning in temperate forests. However, how the forest type affects the stability of the soil food web is not well known. In the Ziwuling forest region of the Loess Plateau, we selected three typical forests, Pinus tabuliformis Carrière (PT), Betula platyphylla Sukaczev (BP), and Quercus liaotungensis Koidz. (QL), to investigate the soil nematode community characteristics in the dry (April) and rainy (August) season, and analyzed their relationships with the soil properties. The results showed that the characteristics of the soil nematode communities and their seasonal variations differed markedly among the forest types. Compared to P. tabuliformis (PT), the B. platyphylla (BP) and Q. liaotungensis (QL) forests had higher plant diversity and more easily decomposed litters, which were more effective for improving the soil resource availability, thus, leading to more beneficial effects on the soil nematode community. In both the dry and rainy season, the soil nematode abundance was the highest in the BP forest. The Shannon–Wiener diversity index (H’), Pielou’s evenness index (J’), and nematode channel ratio index (NCR) were higher, while the Simpson dominance index (λ) and plant parasite index (PPI) were lower, in the BP and QL forests compared with in the PT forest. From the dry to rainy season, the total nematode abundance and the abundance of fungivores, bacterivores, and omnivore-predators, significantly increased in the QL and PT forests, and the values of the Wasilewska index (WI), maturity index (MI), H’, J’, λ, and NCR showed the most significant seasonal variability in the PT forest, which were mainly driven by changes in the soil labile C and N and the moisture content between the two seasons. Generally, the seasonal stability of the soil nematode communities was the highest in the BP forest and the poorest in the PT forest, probably due to variations in the plant diversity. Our results suggest the importance of tree species and diversity as bottom-up regulating factors of the soil food web structure, function, and seasonal stability, which has important implications for sustainable forest management in the Loess Plateau and other temperate regions.

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Nematode diversity, abundance and community structure 50 years after the formation of the volcanic island of Surtsey

Biogeosciences Discussions ◽

10.5194/bgd-11-14239-2014 ◽

2014 ◽

Vol 11 (10) ◽

pp. 14239-14267

Author(s):

K. Ilieva-Makulec ◽

B. Bjarnadottir ◽

B. D. Sigurdsson

Keyword(s):

Community Structure ◽

Soil Depth ◽

Plant Cover ◽

Soil Nematode ◽

Volcanic Island ◽

Nutrient Inputs ◽

Soil C ◽

Nematode Communities ◽

Nematode Diversity ◽

Nematode Abundance

Abstract. The soil nematode fauna can give important insights into soil development and other habitat changes that occur during primary succession. We investigated the generic composition, density, distribution and community structure of nematodes 50 years after the formation of a pristine volcanic island, Surtsey, Iceland. Part of the island has received additional nutrient inputs from seagulls breeding there since 1985, while the reminder has been much less affected and is at present found at a different successional sere. In total, 25 genera of nematodes were identified, of which 14 were reported on Surtsey for the first time. Nematode communities were more diverse in the more infertile area outside the gull colony, where 24 genera were found, compared to 18 inside. The trophic structure of the nematode communities showed relatively higher abundance of fungal feeders in the infertile areas, but relatively more bacterial- and plant-feeders inside the colony. Nematode abundance in surface soil was, however, significantly higher within the gull colony, with 16.7 ind. cm−2 compared to 3.6 ind. cm−2 outside. A multivariate analysis indicated that the nematode abundance and distribution on Surtsey were most strongly related to the soil C : N ratio, soil acidity, plant cover and biomass, soil temperature and soil depth.

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Altitudinal gradient affect abundance, diversity and metabolic footprint of soil nematodes in Banihal-Pass of Pir-Panjal mountain range

Scientific Reports ◽

10.1038/s41598-021-95651-x ◽

2021 ◽

Vol 11 (1) ◽

Author(s):

Shahid Afzal ◽

Humira Nesar ◽

Zarrin Imran ◽

Wasim Ahmad

Keyword(s):

Elevation Gradient ◽

Carbon Assimilation ◽

Shannon Index ◽

Nematode Community ◽

Mountain Range ◽

Soil Nematode ◽

Nematode Communities ◽

Nematode Abundance ◽

Belowground Carbon ◽

Abundance And Diversity

AbstractDespite enormous diversity, abundance and their role in ecosystem processes, little is known about how community structures of soil-inhabiting nematodes differ across elevation gradient. For this, soil nematode communities were investigated along an elevation gradient of 1000–2500 masl across a temperate vegetation in Banihal-Pass of Pir-Panjal mountain range. We aimed to determine how the elevation gradient affect the nematode community structure, diversity and contribution to belowground carbon assimilation in the form of metabolic footprint. Our results showed that total nematode abundance and the abundance of different trophic groups (fungivores, herbivores and omnivores) declined with the increase of elevation. Shannon index, generic richness and evenness index indicated that nematode communities were more diverse at lower elevations and declined significantly with increase in elevation. Nematode community showed a pattern of decline in overall metabolic footprint with the increase of elevation. Nematode abundance and diversity proved to be more sensitive to elevation induced changes as more abundant and diverse nematode assemblage are supported at lower elevations. Overall it appears nematode abundance, diversity and contribution to belowground carbon cycling is stronger at lower elevations and gradually keep declining towards higher elevations under temperate vegetation cover in Banihal-pass of Pir-Panjal mountain range.

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Soil nematode community characteristics around the Gangue hill of Fushun West Open-pit mine

Helminthologia ◽

10.2478/s11687-011-0018-2 ◽

2011 ◽

Vol 48 (2) ◽

pp. 116-123 ◽

Cited By ~ 3

Author(s):

W. Zhang ◽

Y. Xiao ◽

X. Wang ◽

Y. Lv

Keyword(s):

Trophic Group ◽

Scientific Basis ◽

Open Pit Mine ◽

Open Pit ◽

Soil Nematode ◽

Healthy Development ◽

Soil Nematode Community ◽

Single Factor Analysis ◽

Nematode Abundance ◽

Almost All

AbstractDiversity and nematode abundance were investigated in soils collected around the Gangue hill of Fushun West open-pit mine to evaluate soil pollution, due to heavy metals contents, using nematodes as bioindicators. Nematodes were collected from soil samples using elutriate-sievingflotation and centrifugation methods. The species richness and ecological indices were analyzed. On the base of chemical and nematological analysis, the results indicated that the area around the Gangue hill of Fushun West Openpit mine was polluted by heavy metal, but the degree of pollution was not very serious. According to the results obtained from single-factor analysis, cadmium soil content was ten times higher than the background; 29 genera of nematodes were identified and Acrobeloides, Cervidellus and Mesorhabtidis were the dominant genera in almost all sampling sites. The dominant genera were different as the distances to the Gangue hill changed. In particular, in the investigated areas bacterivores and plant-parasites nematodes were more diffuse than fungivores and omnivorepredators. Copper soil content was significantly correlated with plant parasitic trophic group and with total number of nematodes, thus suggesting that nematode communities studies are important scientific basis for understanding the healthy development of soil ecosystem.

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Impact of biochar amendment on soil nematode communities in a West African rain-fed rice cropland

Nematology ◽

10.1163/15685411-bja10121 ◽

2021 ◽

pp. 1-12

Author(s):

Segun O. Oladele ◽

Adebayo Adeyemo ◽

Moses Awodun ◽

Ajoke Adegaye ◽

Mariko Ingold

Keyword(s):

Trophic Group ◽

West African ◽

Nematode Population ◽

Available Phosphorus ◽

Soil Nematode ◽

Trophic Groups ◽

Nematode Communities ◽

Study Results ◽

Inorganic Fertiliser ◽

Plant Parasitic

Summary Nematode population and diversity in a West African rain-fed rice cropland amended with biochar (B), biochar plus inorganic fertiliser (B + NPK), inorganic fertiliser (NPK) and control (CK) without amendments were investigated in a 3-year field study. Results demonstrated that significant differences exist between treatments and years of study for total nematode population and nematode trophic groups. Total nematode density, nematode trophic group (bacterivore and plant-parasitic) density were increased and dominant in B + NPK compared with CK after 3 years. Relative abundance of nematode genera according to trophic group across treatments showed Hirschmanniella (23%) as the dominant plant parasites in NPK, and Heterocephalobus (27%), Aphelenchoides (22%) and Eudorylaimus (9%) as dominant bacterivores, fungivores and omnivores-predators, respectively, in B + NPK. Trophic group indicators showed that the fungivore plus bacterivore to plant-parasitic ratio (73%) was significantly increased by B + NPK treatment in comparison to CK. Conversely, treatments exerted no significant effect on the fungivore to bacterivore ratio (F/B) throughout the period of study, which implies less disturbance and adverse impact of biochar on nematode communities. Apart from treatments and environmental factors, changes in nematode trophic groups were strongly related to soil chemical properties, such as soil pH, total nitrogen and available phosphorus, which shows their influence on soil nematode community. Our result shows the positive effect of integrated addition of biochar and inorganic fertiliser in balancing nematode diversity and building a resilient soil ecosystem in a low input rain-fed rice cropping system.

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Soil Nematode Fauna and Microbial Characteristics in an Early-Successional Forest Ecosystem

Forests ◽

10.3390/f10100888 ◽

2019 ◽

Vol 10 (10) ◽

pp. 888 ◽

Cited By ~ 1

Author(s):

Renčo ◽

Čerevková ◽

Gömöryová

Keyword(s):

Soil Moisture ◽

Moisture Content ◽

Microbial Activity ◽

Soil Moisture Content ◽

Soil Nematode ◽

Nematode Communities ◽

Functional Guilds ◽

Ecosystem Disturbance ◽

Plant Parasites ◽

Nematode Abundance

Windstorms can often decrease the diversity of native local biota in European forests. The effects of windstorms on the species richness of flora and fauna in coniferous forests of natural reserves are well established, but the effects on biotas in productive deciduous forests have been less well studied. We analyzed the impact of windstorms on the diversity and abundance of soil nematode communities and microbial activity and their relationships with the succession of plant species and basic soil physicochemical properties 12 and 36 months after a windstorm in Fagus sylvatica forests. The relationships were investigated in cleared early-successional forest ecosystems and at undamaged forest sites as a control. The windstorm significantly affected total nematode abundance, number of nematode species, and the diversity and abundance of all nematode functional guilds, but no functional guilds disappeared after the disturbance. The abundance of several nematode taxa but not total nematode abundance was positively correlated with soil-moisture content. Indices of the nematode communities were inconsistent between sites due to their variable ability to identify ecosystem disturbance 12 months after the storm. In contrast, the metabolic activity of various functional groups identified ecosystem disturbance well throughout the study. Positive correlations were identified between the number of plant parasites and soil-moisture content and between carnivore abundance and soil pH. Positive mutual links of some nematode genera (mainly plant parasites) with the distribution of dominant grasses and herbs depended on the habitat. In contrast, microbial activity differed significantly between disturbed and undisturbed sites up to 36 months after the storm, especially soil basal respiration, N mineralization, and microbial biomass. Our results indicated different temporal responses for two groups of soil organisms to the destruction of the tree canopy. Soil nematodes reacted immediately, but changes in the microbial communities were visible much later after the disturbance.

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Distinct community structures of soil nematodes from three ecologically different sites revealed by high-throughput amplicon sequencing of four 18S ribosomal RNA gene regions

PLoS ONE ◽

10.1371/journal.pone.0249571 ◽

2021 ◽

Vol 16 (4) ◽

pp. e0249571

Author(s):

Harutaro Kenmotsu ◽

Masahiro Ishikawa ◽

Tomokazu Nitta ◽

Yuu Hirose ◽

Toshihiko Eki

Keyword(s):

High Throughput ◽

Ribosomal Rna ◽

Amplicon Sequencing ◽

Garden Soil ◽

Soil Nematode ◽

Field Soil ◽

Ribosomal Rna Gene ◽

Nematode Communities ◽

18S Ribosomal Rna Gene ◽

Dna Metabarcoding

Quantitative taxonomic compositions of nematode communities help to assess soil environments due to their rich abundance and various feeding habitats. DNA metabarcoding by the 18S ribosomal RNA gene (SSU) regions were preferentially used for analyses of soil nematode communities, but the optimal regions for high-throughput amplicon sequencing have not previously been well investigated. In this work, we performed Illumina-based amplicon sequencing of four SSU regions (regions 1–4) to identify suitable regions for nematode metabarcoding using the taxonomic structures of nematodes from uncultivated field, copse, and cultivated house garden soils. The fewest nematode-derived sequence variants (SVs) were detected in region 3, and the total nematode-derived SVs were comparable in regions 1 and 4. The relative abundances of reads in regions 1 and 4 were consistent in both orders and feeding groups with prior studies, thus suggesting that region 4 is a suitable target for the DNA barcoding of nematode communities. Distinct community structures of nematodes were detected in the taxon, feeding habitat, and life-history strategy of each sample; i.e., Dorylamida- and Rhabditida-derived plant feeders were most abundant in the copse soil, Rhabditida-derived bacteria feeders in the house garden soil, and Mononchida- and Dorylamida-derived omnivores and predators and Rhabditida-derived bacteria feeders in the field soil. Additionally, low- and high-colonizer–persister (cp) groups of nematodes dominated in the house garden and copse soils, respectively, whereas both groups were found in the field soil, suggesting bacteria-rich garden soil, undisturbed and plant-rich copse soil, and a transient status of nematode communities in the field soil. These results were also supported by the maturity indices of the three sampling sites. Finally, the influence of the primer tail sequences was demonstrated to be insignificant on amplification. These findings will be useful for DNA metabarcoding of soil nematode communities by amplicon sequencing.

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Dynamics of Soil Nematode Communities Revealed Significant Variation in Greenhouse with Different Continuous Cropping Years

10.1101/593541 ◽

2019 ◽

Cited By ~ 1

Author(s):

Xueliang Tian ◽

Xiaoman Zhao ◽

Zhenchuan Mao ◽

Bingyan Xie

Keyword(s):

Relative Abundance ◽

Significant Variation ◽

Growing Season ◽

Continuous Cropping ◽

Soil Nematode ◽

Root Knot Nematode ◽

Dominant Group ◽

Nematode Communities ◽

Soil Nematode Community ◽

Soil Nematode Communities

AbstractContinuous cropping usually resulted in a series of soil problems, especially root knot nematode disaster in greenhouse because of imbalance in soil nematode community. However, the dynamic change in soil nematode community in greenhouse with various continuous cropping years during plant growing season is unclear. Here, soil nematode communities in greenhouse after 2 and 10 years of continuous cropping were comparatively analyzed using 18S rDNA high-throughput sequencing to reveal the changing processes in soil nematode communities. Compared to the 2-year greenhouse, soil in the 10-year greenhouse showed soil acidification, nutrients accumulation, salinization. In term of α-diversity, Bacterial-feeding nematodes (BF) were dominant in the 2-year greenhouse over the whole growing season, but plant-parasitic nematodes (PP) became the dominant group in the 10-year greenhouse in the late growing season.Meloidogynegradually became the dominant group (Relative abundance 70.9%) in the 10-year greenhouse, whileRhabditidae(Relative abundance from 99.8% to 26.8%) was the predominant members in the 2-year greenhouse. For β-diversity, hierarchical clustering analysis, unWeighted UniFrac principal component analysis (PCA) and principal co-ordinates analysis (PCoA) all revealed that soil nematode communities in the two types of greenhouses exhibited significant differences. Redundancy analysis (RDA) showed that soil nematode communities in the 10-year greenhouse were related to high soil organic material, total nitrogen, electrical conductivity and disease index of root knot nematode. Fisher’ exact test and Pearson correlation coefficients revealed thatMeloidogynecaused main differences in soil nematode communities between the two types of greenhouses. Meanwhile, population dynamics ofMeloidogynewere divided into dormant phase, low-level increasing phase and exponential phase during the whole season. In total, the significant variation led different dynamics of soil nematode communities in the 2-year and 10-year greenhouse.

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Nature Restoration Shifts the Abundance and Structure of Soil Nematode Communities in Subtropical China

10.21203/rs.3.rs-740625/v1 ◽

2021 ◽

Author(s):

Jianqing Wang ◽

Yingfeng Zheng ◽

Xiuzhen Shi ◽

Shu Kee Lam ◽

Manuel Esteban Lucas-Borja ◽

...

Keyword(s):

Food Web ◽

Secondary Succession ◽

Forest Stand ◽

Nematode Community ◽

Stand Age ◽

Soil Nematode ◽

Soil Food Web ◽

Nature Restoration ◽

Soil Nematode Community ◽

Nematode Abundance

Abstract Aims Soil nematode community is an important component of the soil food web, which has been widely recognized as a key bio-indicator for assessing the influence of nature restoration on ecological functions. However, the dynamics of the abundance, diversity and function of soil nematode community remain unclear under different forest succession phases. Methods The soil nematode community of natural secondary forests was investigated using a chronosequence approach. Nature restoration for five succession stages were sampled in this study to represent a wide range of stand age groups.Results Soil nematode abundance gradually increased with forest stand age, which reached a peak value (574 individuals 100 g-1 dry soil) in the older age classes. In contrast, soil nematode diversity was not affected by forest stand age. Soil available nitrogen and phosphorus were key factors influencing soil nematode abundance and diversity during forest secondary succession. The plant parasite index decreased with forest stand age, which indicated that ecosystem function and health would be improved as nature restoration progresses. In addition, the structure of soil nematode community was more sensitive to forest secondary succession compared to plant community and soil microbial community. The bottom-up effects of the plant and microbial communities on soil nematode community were important drivers of nematode community structure in subtropical forests. Conclusions Overall, this study demonstrates the active responses of soil nematode community to nature restoration, and highlights the importance of the above-ground and below-ground interactions to the soil food web.

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