scholarly journals The Regulation by Phenolic Compounds of Soil Organic Matter Dynamics under a Changing Environment

2015 ◽  
Vol 2015 ◽  
pp. 1-11 ◽  
Author(s):  
Kyungjin Min ◽  
Chris Freeman ◽  
Hojeong Kang ◽  
Sung-Uk Choi
Keyword(s):  
Organic Matter ◽  
Soil Organic Matter ◽  
Environmental Changes ◽  
N Deposition ◽  
Interactive Effects ◽  
Plant Metabolites ◽  
Regulatory Effects ◽  
Dynamics Models ◽  
The Relationship

Phenolics are the most abundant plant metabolites and are believed to decompose slowly in soils compared to other soil organic matter (SOM). Thus, they have often been considered as a slow carbon (C) pool in soil dynamics models. Here, however, we review changes in our concept about the turnover rate of phenolics and quantification of different types of phenolics in soils. Also, we synthesize current research on the degradation of phenolics and their regulatory effects on decomposition. Environmental changes, such as elevated CO2, warming, nitrogen (N) deposition, and drought, could influence the production and form of phenolics, leading to a change in SOM dynamics, and thus we also review the fate of phenolics under environmental disturbances. Finally, we propose the use of phenolics as a tool to control rates of SOM decomposition to stabilize organic carbon in ecosystems. Further studies to clarify the role of phenolics in SOM dynamics should include improving quantification methods, elucidating the relationship between phenolics and soil microorganisms, and determining the interactive effects of combinations of environmental changes on the phenolics production and degradation and subsequent impact on SOM processing.

Parenting Behaviors and Anxiety in Young Adults

2015 ◽  
Vol 36 (3) ◽  
pp. 170-176 ◽  
Author(s):  
Erin N. Stevens ◽  
Joseph R. Bardeen ◽  
Kyle W. Murdock
Keyword(s):  
Effortful Control ◽  
Parenting Behaviors ◽  
Protective Role ◽  
Anxiety Symptoms ◽  
Interactive Effects ◽  
Parental Overprotection ◽  
High Control ◽  
Development Of Anxiety ◽  
The Relationship

Parenting behaviors – specifically behaviors characterized by high control, intrusiveness, rejection, and overprotection – and effortful control have each been implicated in the development of anxiety pathology. However, little research has examined the protective role of effortful control in the relation between parenting and anxiety symptoms, specifically among adults. Thus, we sought to explore the unique and interactive effects of parenting and effortful control on anxiety among adults (N = 162). Results suggest that effortful control uniquely contributes to anxiety symptoms above and beyond that of any parenting behavior. Furthermore, effortful control acted as a moderator of the relationship between parental overprotection and anxiety, such that overprotection is associated with anxiety only in individuals with lower levels of effortful control. Implications for potential prevention and intervention efforts which specifically target effortful control are discussed. These findings underscore the importance of considering individual differences in self-regulatory abilities when examining associations between putative early-life risk factors, such as parenting, and anxiety symptoms.

T4-like Phages Reveal the Potential Role of Viruses in Soil Organic Matter Mineralization

2021 ◽  
Author(s):  
Xiaomeng Wei ◽  
Tida Ge ◽  
Chuanfa Wu ◽  
Shuang Wang ◽  
Kyle Mason-Jones ◽  
...  
Keyword(s):  
Organic Matter ◽  
Soil Organic Matter ◽  
Potential Role ◽  
Organic Matter Mineralization

scholarly journals DOM degradation by light and microbes along the Yukon River-coastal ocean continuum

2021 ◽  
Vol 11 (1) ◽  
Author(s):  
Brice K. Grunert ◽  
Maria Tzortziou ◽  
Patrick Neale ◽  
Alana Menendez ◽  
Peter Hernes
Keyword(s):  
Organic Matter ◽  
Dissolved Organic Matter ◽  
Salinity Gradient ◽  
Coastal Ocean ◽  
Interactive Effects ◽  
The Arctic ◽  
Yukon River ◽  
Spring Freshet ◽  
Dom Composition

AbstractThe Arctic is experiencing rapid warming, resulting in fundamental shifts in hydrologic connectivity and carbon cycling. Dissolved organic matter (DOM) is a significant component of the Arctic and global carbon cycle, and significant perturbations to DOM cycling are expected with Arctic warming. The impact of photochemical and microbial degradation, and their interactive effects, on DOM composition and remineralization have been documented in Arctic soils and rivers. However, the role of microbes, sunlight and their interactions on Arctic DOM alteration and remineralization in the coastal ocean has not been considered, particularly during the spring freshet when DOM loads are high, photoexposure can be quite limited and residence time within river networks is low. Here, we collected DOM samples along a salinity gradient in the Yukon River delta, plume and coastal ocean during peak river discharge immediately after spring freshet and explored the role of UV exposure, microbial transformations and interactive effects on DOM quantity and composition. Our results show: (1) photochemical alteration of DOM significantly shifts processing pathways of terrestrial DOM, including increasing relative humification of DOM by microbes by > 10%; (2) microbes produce humic-like material that is not optically distinguishable from terrestrial humics; and (3) size-fractionation of the microbial community indicates a size-dependent role for DOM remineralization and humification of DOM observed through modeled PARAFAC components of fluorescent DOM, either through direct or community effects. Field observations indicate apparent conservative mixing along the salinity gradient; however, changing photochemical and microbial alteration of DOM with increasing salinity indicate changing DOM composition likely due to microbial activity. Finally, our findings show potential for rapid transformation of DOM in the coastal ocean from photochemical and microbial alteration, with microbes responsible for the majority of dissolved organic matter remineralization.

scholarly journals Fractionation of Heavy Metals in Multi-Contaminated Soil Treated with Biochar Using the Sequential Extraction Procedure

Biomolecules ◽  
2021 ◽  
Vol 11 (3) ◽  
pp. 448
Author(s):  
Mahrous Awad ◽  
Zhongzhen Liu ◽  
Milan Skalicky ◽  
Eldessoky S. Dessoky ◽  
Marian Brestic ◽  
...  
Keyword(s):  
Heavy Metals ◽  
Organic Matter ◽  
Soil Organic Matter ◽  
Soil Ph ◽  
Contaminated Soil ◽  
Contaminated Soils ◽  
Extraction Procedure ◽  
Sequential Fractionation ◽  
Relationship Of ◽  
The Relationship

Heavy metals (HMs) toxicity represents a global problem depending on the soil environment’s geochemical forms. Biochar addition safely reduces HMs mobile forms, thus, reducing their toxicity to plants. While several studies have shown that biochar could significantly stabilize HMs in contaminated soils, the study of the relationship of soil properties to potential mechanisms still needs further clarification; hence the importance of assessing a naturally contaminated soil amended, in this case with Paulownia biochar (PB) and Bamboo biochar (BB) to fractionate Pb, Cd, Zn, and Cu using short sequential fractionation plans. The relationship of soil pH and organic matter and its effect on the redistribution of these metals were estimated. The results indicated that the acid-soluble metals decreased while the fraction bound to organic matter increased compared to untreated pots. The increase in the organic matter metal-bound was mostly at the expense of the decrease in the acid extractable and Fe/Mn bound ones. The highest application of PB increased the organically bound fraction of Pb, Cd, Zn, and Cu (62, 61, 34, and 61%, respectively), while the BB increased them (61, 49, 42, and 22%, respectively) over the control. Meanwhile, Fe/Mn oxides bound represents the large portion associated with zinc and copper. Concerning soil organic matter (SOM) and soil pH, as potential tools to reduce the risk of the target metals, a significant positive correlation was observed with acid-soluble extractable metal, while a negative correlation was obtained with organic matter-bound metal. The principal component analysis (PCA) shows that the total variance represents 89.7% for the TCPL-extractable and HMs forms and their relation to pH and SOM, which confirms the positive effect of the pH and SOM under PB and BB treatments on reducing the risk of the studied metals. The mobility and bioavailability of these metals and their geochemical forms widely varied according to pH, soil organic matter, biochar types, and application rates. As an environmentally friendly and economical material, biochar emphasizes its importance as a tool that makes the soil more suitable for safe cultivation in the short term and its long-term sustainability. This study proves that it reduces the mobility of HMs, their environmental risks and contributes to food safety. It also confirms that performing more controlled experiments, such as a pot, is a disciplined and effective way to assess the suitability of different types of biochar as soil modifications to restore HMs contaminated soil via controlling the mobilization of these minerals.

Influence of soil organic matter on sulfate retention in two Podzols in Quebec, Canada

1999 ◽  
Vol 79 (1) ◽  
pp. 103-109 ◽  
Author(s):  
F. Courchesne ◽  
J.-F. Laberge ◽  
A. Dufresne
Keyword(s):  
Organic Matter ◽  
Soil Organic Matter ◽  
Ammonium Oxalate ◽  
X Ray Diffraction ◽  
Weighted Mean ◽  
Fine Silt ◽  
Mineral Horizon ◽  
Organic C ◽  
X Ray

The role of soil organic matter (OM) on SO4 retention was investigated by comparing OM content, SO4 retention, and the distribution of Fe, Al and Si compounds in OM-poor (Grands-Jardins, PGJ) and OM-rich (Hermine, HER) Podzols from Québec, Canada. At both sites, four pedons were sampled by horizon; soil pH in H2O, organic C, phosphate-extractable SO4 and, sodium pyrophosphate, acid ammonium oxalate and dithionite-citrate-bicarbonate (DCB) extractable Fe, Al and Si were measured for each mineral horizon. The mineralogy of the clay (<2 µm) and fine silt (2–20 µm) fractions of selected horizons was determined by X-ray diffraction (XRD) and infrared spectroscopy (IR). Weighted mean organic C and pyrophosphate extractable Fe and Al contents were significantly higher in the HER than in the PGJ sola, while the PGJ soils were richer in amorphous inorganic Al. No trends were observed for inorganic Fe compounds. Chemical dissolution and IR allowed the identification of short-range ordered aluminosilicates, probably allophane, in the OM-poor and slightly acidic to neutral PGJ soils. These materials were absent from the OM-rich and acidic HER soils. Phosphate extractions showed that the weighted mean native SO4 content was five times higher in the PGJ than in the HER soil. Finally, native SO4 was strongly related to inorganic Fe, Al and Si (associated with allophane) at PGJ but only to inorganic Fe at HER. These results indicate that OM indirectly affects SO4 sorption through the influence organic substances exerts on the nature and distribution of pedogenic Fe, Al and Si compounds, such as allophane, in Podzolic profiles. Key words: Organic matter, sulfate, imogolite, allophane, silica, Podzol

scholarly journals Monitoring studies should consider temporal variability to reveal relations between cyanobacterial abundance and environmental variables

2015 ◽  
Vol 87 (3) ◽  
pp. 1717-1726 ◽  
Author(s):  
JULIANA WOJCIECHOWSKI ◽  
ANDRÉ A. PADIAL
Keyword(s):  
Temporal Variability ◽  
Environmental Variables ◽  
Environmental Changes ◽  
Environmental Variability ◽  
Time Lag ◽  
Cyanobacteria Blooms ◽  
Environment Variables ◽  
Sampling Points ◽  
The Relationship

One of the main goals of monitoring cyanobacteria blooms in aquatic environments is to reveal the relationship between cyanobacterial abundance and environmental variables. Studies typically correlate data that were simultaneously sampled. However, samplings occur sparsely over time and may not reveal the short-term responses of cyanobacterial abundance to environmental changes. In this study, we tested the hypothesis that stronger cyanobacteria x environment relationships in monitoring are found when the temporal variability of sampling points is incorporated in the statistical analyses. To this end, we investigated relationships between cyanobacteria and seven environmental variables that were sampled twice yearly for three years across 11 reservoirs, and data from an intensive monitoring in one of these reservoirs. Poor correlations were obtained when correlating data simultaneously sampled. In fact, the 'highly recurrent' role of phosphorus in cyanobacteria blooms is not properly observed in all sampling periods. On the other hand, the strongest correlation values for the total phosphorus x cyanobacteria relationship were observed when we used the variation of sampling points. We have also shown that environment variables better explain cyanobacteria when a time lag is considered. We conclude that, in cyanobacteria monitoring, the best approach to reveal determinants of cyanobacteria blooms is to consider environmental variability.

scholarly journals Organik Matter: It’s Role in Sustainable Farming of Sugarcane

Perspektif ◽  
2016 ◽  
Vol 14 (1) ◽  
pp. 61
Author(s):  
Djajadi Djajadi
Keyword(s):  
Organic Matter ◽  
Soil Organic Matter ◽  
Soil Fertility ◽  
Green Manure ◽  
Organic Fertilizer ◽  
Soil Health ◽  
High Yield ◽  
Cane Yield ◽  
Sustainable Farming

<p class="Default">ABSTRACT</p><p class="Default">Organik matter has an important role in determining soil health of sugarcane, i.e. soil capacity to support sugarcane to produce sustainable high yield. Soil organic matter influences soil physical, chemical, and biological properties, so that a consequence of declining soil organic matter is poorer soil fertility and lower yield. This paper has an objective to elucidate the important role of organic matter on sustainable farming of sugarcane. The important role of organic matter in soil fertility has been known for a long time before Green Revolution concept was introduced. With more intensity in sugarcane farming and more increasing of sugar demand, application of organic fertilizer started to be substituted by chemical fertilizer. Using green manure and/or biofertilizer has a chance to be spread out to the farmers due to more practical and more efficient than solid organik fertilizer, such as dung manure or compost. Future research should be focusing on the efectivity of green manure and or biofertilzer sources in improving soil fertility and cane yield, minimizing soil pathogen, reducing soil erosion of sugar cane land monoculture, and improving awareness of farmers about soil degradation as consequences of sugarcane monoculture planting for years.</p><p class="Default">Keywords: Organic matter, sugarcane, soil health sustainable farming</p><p class="Default"> </p><p class="Default"><strong>Bahan Organik: Peranannya dalam Budidaya Tebu Berkelanjutan</strong></p><p class="Default">ABSTRAK</p><p class="Default">Bahan organik tanah berperan penting dalam menentukan kesehatan tanah tebu, yaitu kapasitas tanah yang dapat mendukung produksi tebu yang tinggi secara berkelanjutan. Kadar bahan organik tanah mempengaruhi sifat fisik, kimia dan biologi tanah. Paper ini bertujuan untuk menguraikan tentang peranan bahan organik dalam memperbaiki sifat fisik, kimia dan biologi tanah pertanaman tebu. Pentingnya peran bahan oganik tersebut sudah disadari dari dulu, sehingga sebelum revolusi hijau penggunaan pupuk organik sudah umum dilakukan petani. Dengan semakin intensifnya budidaya tebu dan semakin meningkatnya kebutuhan gula, pemanfaatan pupuk organik sudah jarang dilakukan. Diperlukan usaha untuk meningkatkan dan mempertahankan kadar bahan organik pada lahan tebu, antara lain berupa gerakan masal dalam bentuk gerakan nasional melalui program aplikasi bahan organik. Pemanfaatan pupuk hijau dan/atau pupuk hayati berpeluang untuk diterapkan karena lebih praktis dan efisien daripada penambahan pupuk organik padat. Penelitian ke depan perlu difokuskan untuk mengkaji jenis-jenis pupuk organik dan pupuk hayati yang efektif memperbaiki kesuburan, dalam menekan serangan penyakit, meminimalkan erosi pada lahan-lahan tebu monokultur, dan meningkatkan kesadaran petani tebu tentang terjadinya degradasi lahan akibat penanaman tebu yang terus menerus.</p><p class="Default">Kata kunci: Bahan organik, tebu, kesehatan tanah, budidaya berkelanjutan</p><p class="Default"> </p>

The role of soil depth in the evaluation of management-induced effects on soil organic matter

2017 ◽  
Vol 68 (6) ◽  
pp. 979-987 ◽  
Author(s):  
L. Knebl ◽  
G. Leithold ◽  
F. Schulz ◽  
C. Brock
Keyword(s):  
Organic Matter ◽  
Soil Organic Matter ◽  
Soil Depth
Sign in / Sign up

Export Citation Format

Share Document