Earthworm effects on soil biogeochemistry in temperate forests focusing on stable isotope tracing: a review

Kim Gaeun,Jo Heejae,Kim Hyung-Sub,Kwon Minyoung,Son Yowhan 한국응용생명화학회 2022 Applied Biological Chemistry (Appl Biol Chem) Vol.65 No.6

Earthworms (Oligochaeta) are globally distributed soil-dwelling invertebrates that alter soil properties through feeding, casting, and burrowing behaviors. Soil physicochemical modification, which may directly influence the availability and dynamics of organic and inorganic nutrients in the soil, such as carbon and nitrogen, includes soil texture, porosity, and pH. Temperate forests produce year-round plant litter, the primary food source for earthworms, and litter processed by earthworms significantly contributes to soil organic material storage. In recent decades, studies on temperate forest ecosystems have attempted to elucidate and quantify the earthworm impact on soil organic material dynamics, mainly targeting carbon and nitrogen, using isotope analysis methods. This paper summarizes studies on the following topics: (1) effect of earthworm modification on soil property to understand these alterations’ interaction with carbon and nitrogen dynamics, and (2) isotope tracing method, used to elucidate the earthworm effect on carbon and nitrogen transformation and movements in temperate forests. The particular emphasis on the isotope method is based on its capability of time-adjusted quantification of organic materials in the ecosystem compartments. Also, isotopic labeling in biomass has a broad range of applications, such as tracing assimilated food sources, identifying trophic interactions in soil food webs, and addressing material dynamics in complex linkages between earthworms and their environment. In addition, we provide perspectives on other methodologies, such as chronology and population ecology, as feasible options to further assist the isotope tracing of earthworms’ impact on soil nutrient dynamics. Earthworms (Oligochaeta) are globally distributed soil-dwelling invertebrates that alter soil properties through feeding, casting, and burrowing behaviors. Soil physicochemical modification, which may directly influence the availability and dynamics of organic and inorganic nutrients in the soil, such as carbon and nitrogen, includes soil texture, porosity, and pH. Temperate forests produce year-round plant litter, the primary food source for earthworms, and litter processed by earthworms significantly contributes to soil organic material storage. In recent decades, studies on temperate forest ecosystems have attempted to elucidate and quantify the earthworm impact on soil organic material dynamics, mainly targeting carbon and nitrogen, using isotope analysis methods. This paper summarizes studies on the following topics: (1) effect of earthworm modification on soil property to understand these alterations’ interaction with carbon and nitrogen dynamics, and (2) isotope tracing method, used to elucidate the earthworm effect on carbon and nitrogen transformation and movements in temperate forests. The particular emphasis on the isotope method is based on its capability of time-adjusted quantification of organic materials in the ecosystem compartments. Also, isotopic labeling in biomass has a broad range of applications, such as tracing assimilated food sources, identifying trophic interactions in soil food webs, and addressing material dynamics in complex linkages between earthworms and their environment. In addition, we provide perspectives on other methodologies, such as chronology and population ecology, as feasible options to further assist the isotope tracing of earthworms’ impact on soil nutrient dynamics.

Current Research Trends on the Effects of Microplastics in Soil Environment Using Earthworms: Mini-Review

Jaeryung Hur,Eun Hea Jho 대한환경공학회 2021 대한환경공학회지 Vol.43 No.4

Objectives : The increase in the amount of plastics used has brought convenience to human life, but has also caused various environmental problems such as problems related to microplastics. Microplastics are defined as small plastic particles with a size of under 5 mm. As of now, research on microplastics has been largely focusing on the marine environment, and studies on microplastics in soil environment are on the rise in very recent years. Thus, the environmental impact of microplastics on the soil environment are insufficient than those on the marine environment, and there is a need for more studies. Therefore, this mini-review attempts to examine the studies on microplastics in soil environment focusing on the studies using earthworms as a test species. Methods : Published studies on microplastics in soil environment were identified by searching Web of Science. The focus of this mini-review was to gather the published articles reporting the effect of microplastics on earthworms in the absence and presence of other chemical contaminants. Results and Discussions : The number of studies evaluating the effect of microplastics in soil are significantly increasing, and earthworms are being mostly used as the test species. Experimental conditions were divided into two types: Single exposure to microplastics and combined exposure to microplastics and other chemicals. In most studies, changes in the biomarkers which are related to oxidation stress of earthworms were confirmed, and direct damage to intestinal tissues of earthworms was also observed. However, in the case of the changes of the biomarkers of earthworms, their patterns were different depending on the experimental conditions (i.e.,concentrations of microplastics and chemicals, microplastics size and type, exposure period, etc.). Also, the avoidance behavior of earthworms and the internal accumulation of microplastics and co-existing chemicals were not consistent among the studies. Thus, the effects of microplastics on earthworms are not clear yet, although they seem to have some adverse effects. Conclusions : This study showed that the interest in the impact of microplastics in the soil environment has been increased recently, and earthworms are being used mostly in the studies. Yet, there is no standardized method to study the effect of microplastics on earthworms. Studies so far confirmed that microplastics induced changes in and outside of earthworm bodies. However, due to various experimental conditions, it seemed that consistent results could not be confirmed in those researches. For that reason, this study suggests that standardized research methods for microplastics researches using earthworms as a test species need to be established and need to be applied to further studies.

온대 숲 토양 생태계에서 지렁이가 톡토기류 개체수에 미치는 영향

이주형 ( Ju Hyung Lee ),박지현 ( Ji Hyun Park ),유지연 ( Ji Yeon Yoo ),한수현 ( Su Hyun Han ),남보은 ( Bo Eun Nam ),김재근 ( Jae Geun Kim ) 한국환경복원기술학회(구 한국환경복원녹화기술학회) 2010 한국환경복원기술학회지 Vol.13 No.6

Earthworm, a prominent ecosystem engineer within many terrestrial ecosystems, can exert profound influences on various abiotic/biotic environments through bioturbation processes such as burrowing, casting and mixing of litter and soil. In this study, we investigated how the presence or absence of earthworm (Oligochaeta) can alter the soil physico-chemical conditions and ultimately the distribution and abundance of Collembola which constitutes a large proportion of the soil fauna. During September 2010, soil organisms along with soil samples were collected from randomly installed 20 plots in Mt. Gwan-ak. We examined the differences in the abundance of Collembola among plot samples in respect to the presence/absence of earthworm and soil physico-chemical conditions (i.e., pH, PO43-, NO32-, organic matter (OM), electrical conductance and water content). Analysis of soil physico-chemical environment revealed a significantly higher organic matter content and electrical conductance in plots with earthworm compared to plots without earthworm. Abundance of Collembola were not only higher in plots with earthworm than in plots without earthworm, but were also positively correlated with availability of OM present in the environment. The results suggest that positive impacts of earthworm on the abundance of Collembola in this study may have been due to their ability to effectively modify soil physico-chemical conditions favored by Collembola. Such conspicuous influence of earthworm`s activity on below-ground community suggests their potential significance in forest restoration or revegetation process.

큰빛반 유아의 지렁이 놀이 과정과 경험의 의미

이송희,조형숙 한국영유아교원교육학회 2023 유아교육학논집 Vol.27 No.4

The study aimed to explore the process of earthworm play, as led by children, to understand the experiences had during play. The subjects of this study were 24 five-year-old children in the Keunbit class of a public kindergarten in city A. The researcher collected and recorded the play situations that emerged from children’s interest in and curiosity of earthworms discovered by chance in nature, through participatory observation, photography, or video recordings. By repeatedly interpreting and analyzing the text, the study explored the process of play and the meaning of play experience. The children in the Keunbit class took the initiative when playing and expanded their exploration of earthworms into various activities through the processes of ‘first meeting with earthworms', ‘waiting for earthworms', ‘playing with earthworms', and ‘parting with earthworms'. The results of interpreting the play experience concern ‘becoming a collaborator who shares in the experience of play and joy', ‘becoming an exploratory learner who enjoys the process of exploration', ‘'becoming someone who practices caring and sending' and ‘becoming an eco-friendly practitioner who wishes to coexist happily with earthworms'. Through these results, this study elucidates upon children’s ability to learn through play, which concerns both the content and process. Additionally, it emphasizes the necessity and importance of play-centered ecological activities (such as play related to raising animals) in early childhood educational institutions.

<지렁이 국으로 시어머니 봉양한 며느리> 이야기에 형상화된 지렁이의 생물학적 특징과 작품 세계

정규식(Chung, Ku-Sik) 부산대학교 한국민족문화연구소 2015 한국민족문화 Vol.54 No.-

본고는 지렁이가 등장하는 대표적인 구비설화인 <지렁이 국으로 시어머니 봉양한 며느리> 이야기의 작품 세계를 지렁이의 생물학적 특징을 중심으로 논의하는 것을 목적으로 한다. 이를 통해 지렁이의 생물학적 특징과 이 작품이 어떻게 연관되는가를 살피고 나아가 작품의 의미를 새롭게 해석하고자 했다. 논의의 결과 다음과 같은 결론에 도달하였다. <지렁이 국으로 시어머니 봉양한 며느리> 이야기는 접근성, 지속성, 약효성, 징그러움 등 지렁이의 생물학적 특징을 충실히 반영하고 있음을 알 수 있었다. 또한 작품은 시종일관 시선의 문제를 중요하게 다루고 있는데 이는 시각을 상실한 시어머니와 눈이 없는 지렁이의 상동성과 연관된다. 눈이 없으면서 입으로 먹기만 하는 지렁이가 자연 생태계의 복원이라는 재생의 기능을 하듯, 작품 속 시어머니 역시 시각을 상실한 상태에서 입으로 먹기만 하다가 지렁이를 먹고서 눈을 뜨게 되면서 가족 생태계가 복원된다는 의미로 해석할 수 있는 것이다. 따라서 <지렁이 국으로 시어머니 봉양한 며느리> 이야기의 지렁이는 자연 상태에서 자연 생태계 복원이라는 생물학적 기능을 수행한 것이 아니라 우리의 설화 문학에서 눈이 먼 시어머니의 눈을 뜨게 하여 가족 생태계 복원이라는 문학적 기능을 수행하는 문화적 지렁이로 재탄생하게 된 것이다. 그리고 이러한 문화적 지렁이의 탄생은 지렁이가 지닌 고유한 생물학적 특징과 밀접하게 연관되어 있다고 할 수 있다. The purpose of his study was to consider <A Daughter-In-Law who Served Her Mother-In-Law with an Earthworm Soup>, an orally transmitted narrative whose main character is the earthworm, by focusing on biological characteristics of the living creature. More specifically, the study tried to examine how those characteristics are associated with the narrative and newly interpret the meaning of the story. The findings of this study can be summarized as follows. <A Daughter-In-Law who Served Her Mother-In-Law with an Earthworm Soup> well reflects such biological characteristics of the earthworm such as accessibility, sustainability, medicinal effectiveness and creepiness. The narrative constantly regards eyes as an important issue, associating the mother-in-law who lost her sight with the earthworm that has no eyes. Like the no-eyed earthworm plays a role in regenerating the natural ecosystem just by eating with his mouth, the mother-in-law who is blind opens her eyes by eating that earthworm, which implies the regeneration of family’s ecosystem. In <A Daughter-In-Law who Served Her Mother-In-Law with an Earthworm Soup>, thus, the earthworm is not just a creature that performs a biological function, or restoration of the natural ecosystem, but reborn as a cultural being that performs a cultural function, or restoration of family’s ecosystem through opening the mother-in-law’s eyes from the perspective of the narrative literature. The rebirth has close relationships with biological characteristics of the earthworm.

비소 오염 토양에서 개량제 처리가 지렁이의 비소 흡수에 미치는 영향

류지혁,전경미,권오도,우정옥,윤지현 한국환경분석학회 2022 환경분석과 독성보건 Vol.25 No.4

This study was conducted to evaluate the effects of soil amendments on arsenic (As) bioavailability in As-polluted soils. We determined the subsequent changes in As toxicity toward earthworms (Eisenia fetida) and As uptake by earthworms. We also investigated whether As bioaccumulation could be used as an index to evaluate changes in quality of As-polluted soils. No significant changes in acute toxicity to earthworms were observed, and the observed increases (70-93 mg kg-1) or decreases (27-38 mg kg-1) in bioavailable As in soils at the end of test were not related to the As concentrations in earthworms. The As concentration in earthworms 14 days after exposure was significantly lower in calcium superphosphate (CSP)- and S-treated soils (101.4-112.8 mg kg-1) than in control soil (138.9 mg kg-1), probably owing to reduced earthworm growth due to lower pH in CSP- and S-treated soils (6.3-7.3) relative to control and steel slag-treated soils (7.5-8.4). Comparisons of As toxicity and the effects of soil properties on this toxicity toward various species of earthworms could facilitate the use of earthworms to produce biological indices for evaluating changes in quality of As-polluted soils following amendment treatments.

Identification and Characterization of Microbial Community in the Coelomic Fluid of Earthworm (Aporrectodea molleri)

( Lamia Yakkou ),( Sofia Houida ),( Jorge Dominguez ),( Mohammed Raouane ),( Souad Amghar ),( Abdellatif El Harti ) 한국미생물 · 생명공학회 2021 한국미생물·생명공학회지 Vol.49 No.3

Earthworms play an important role in soil fertilization, interacting continually with microorganisms. This study aims to demonstrate the existence of beneficial microorganisms living in the earthworm’s immune system, the coelomic fluid. To achieve this goal, a molecular identification technique was performed, using cytochrome c oxidase I (COI) barcoding to identify abundant endogenic earthworms inhabiting the temperate zone of Rabat, Morocco. Then, 16S rDNA and ITS sequencing techniques were adopted for bacteria and fungi, respectively. Biochemical analysis, showed the ability of bacteria to produce characteristic enzymes and utilize substrates. Qualitative screening of plant growth-promoting traits, including nitrogen fixation, phosphate and potassium solubilization, and indole acetic acid (IAA) production, was also performed. The result of mitochondrial COI barcoding allowed the identification of the earthworm species Aporrectodea molleri. Phenotypic and genotypic studies of the sixteen isolated bacteria and the two isolated fungi showed that they belong to the Pseudomonas, Aeromonas, Bacillus, Buttiauxella, Enterobacter, Pantoea, and Raoultella, and the Penicillium genera, respectively. Most of the isolated bacteria in the coelomic fluid showed the ability to produce β-glucosidase, β-glucosaminidase, Glutamyl-β-naphthylamidase, and aminopeptidase enzymes, utilizing substrates like aliphatic thiol, sorbitol, and fatty acid ester. Furthermore, three bacteria were able to fix nitrogen, solubilize phosphate and potassium, and produce IAA. This initial study demonstrated that despite the immune property of earthworms’ coelomic fluid, it harbors beneficial microorganisms. Thus, the presence of resistant microorganisms in the earthworm's immune system highlights a possible selection process at the coelomic fluid level.

몇 가지 응집제의 지렁이에 대한 독성 및 그들 응집제로 응집된 하수슬러지가 붉은줄지렁이 생장에 미치는 영향

배윤환,신현곤 한국폐기물자원순환학회 2015 한국폐기물자원순환학회지 Vol.32 No.2

Toxicity of polymer, Alum, Zeolite, Loess, Koalinite and Chitosan on earthworm and the effects of sewage sludges coagulated by several mixtures of those coagulants on the population growth of earthworm Eisenia andrei were evaluated. Under the concentration of 20,000 mg/L of Zeolite, Loess and Kaolinite, and under 1,000 mg/L of Chitosan were there no acute toxicities on earthworms. The concentration of Polymer over 160 mg/L showed acute toxicity upon earthworm, but the concentration under 80 mg/L showed no toxicity. The concentration of Alum over 125 mg/L showed acute toxicity. The mixture of ‘Polymer 80 mg/L + Kaolinite 500 mg/L + Chitosan 20 mg/L’ had higher coagulating efficiency than the ‘Polymer 80 mg/ L + Kaolinite 500 mg/L’ on sewage sludge, And the sewage sludge coagulated by former mixture induced higher growth rate of earthworm population than that coagulated by latter mixture when the sewage sludges were supplied to earthworms.

지렁이 자가분해물 컨디셔너가 펌에 미치는 효과

유세은 ( You Se Eun ),강상모 ( Sang Mo Kang ) 한국미용학회 2010 한국미용학회지 Vol.16 No.4

This study aims to develop a product using earthworm`s autolyzed peptides. After applying the earthworm conditioner before and after the chemical administration, this paper observed its treatment effect and retentivity. This article studied how the earthworm conditioner affects hair when it penetrates permed hair through basic physical property tests and SEM and observed its morphological changes. The experimental group treated with the conditioner having earthworm`s autolysate before and after the administration to permed hair had significantly thicker and heavier hair than the normal permed hair or the control group in general. Moreover, its retentivity according to the times of shampooing was significantly higher than the normal permed hair or the control group. Also, the experimental group showed a higher amino acid content than the normal hair or the control group. And the experimental group treated with the earthworm conditioner indicated higher wave efficiency of permed hair than the control group. The tensile force was also significantly higher in the experimental group than the normal hair or the control group. And this remained significantly high even after the 20 times of shampooing. In the observation with an optical microscope and SEM, the experimental group had smooth surface with the surface of the outer layer neatly arranged. The arrangement of the scale remained the same even after the 10 times of shampooing. It is thought that the retentive force together with the scale arrangement was increased as the earthworm autolysate peptide filled in the matrix slipped out due to the damage and wrapped the surface by being adhered well because it has the strong polarization for the hair with the negative ion through the disufide (s-s) bond created in perming after the pretreatment of the chemical treatment and the electrostatic interaction created by the post-treatment. Putting these results together, it is thought that the earthworm autolysate peptide, a natural material, is valuable to apply as a new conditioner ingredient.

유기성폐기물과 밭토양에 대한 붉은줄지렁이와 밭지렁이의 섭식 전후의 분변토 발생량 및 오염물질의 함량 변화

나영은 ( Young Eun Na ) 한국환경농학회 2015 한국환경농학회지 Vol.34 No.2

BACKGROUND: Earthworms are essential detritus feeders that play a vital role in the process of decomposition of organic matter and soil metabolism. The complex process of partial breakdown of organic matter and mixing with mucous and gut microbial flora in the form of earthworm cast results in the reduction of the toxicity. This study focused on the change of cast amount and pollutant contents before and after the eating of the organic waste and upland soil with the two species of earthworm. METHODS AND RESULTS: The two species of earthworms were compared to the cast production. In the upland soil material, the daily amount of worm’s cast was 1.42 g in E. andrei and 0.40 g in A. agrestis. In the organic waste material, the cast of E. andrei was 0.78~0.83 g and the cast of A. agrestis. have not been collected because all earthworms died after the treatment. The heavy metals treated in the upland soil were evaluated the impact of the worm excretion. With the E. andrei, the cast production was decreased 0.1~0.8 times in zinc, 0.2~0.5 times in copper, and 0.1~0.7 times in cadmium compared to the control treatment according to the levels of concentration. With A. agrestis, the cast amount was decreased 0.3~1.1 times in zinc, 0.2~0.3 times in copper, and 0.1~2.1 times in cadmium, respectively. The changes of pollutant contents before and after the eating of the organic wastes with E. andrei were studied. In the treatment of the Alcohol Fermentation Processing Sludge and the Fruit Juice Processing Sludge, heavy metal content of the cast was increased 0.7~53.3% compared to the sludge materials. PAHs contents were decreased 50.1% in the cast of the Alcohol Fermentation Processing Sludge and 36.6% in the cast of the Fruit Juice Processing Sludge, respectively. CONCLUSION: In conclusion, although the A. agrestis was bigger than E. andrei in size and weight, the cast amount of A. agrestis was small. The two species of earthworm was less excretion with high concentration of heavy metals. While the heavy metals such as zinc, copper, and cadmium were considerably accumulated in the cast, the total compounds, PAHs were fairly decomposed. There results would provide us for restoring contaminated soil and cleaning organic wastes.