Effects of straw return and aeration on oxygen status and redox environment in flooded soil

To study the effects of straw return and aeration of the water layer on oxygen and redox status in the water column and at different depths in paddy field soil, a short-term incubation experiment was conducted with four treatments: (1) no straw return (NS); (2) straw return without aeration (S); (3) straw return and 30 minutes of aeration per day (SO30); and (4) straw return and 90 minutes of aeration per day (SO90). Compared to NS, S decreased dissolved oxygen (DO) and redox potential (ORP) by 23–58% and 47–53 mV, respectively, and increased active reducing substance (ARS) by 21–46% in the water and soil layers. The aeration treatments increased DO and ORP by 25–120% and 11–86 mV, respectively, and reduced ARS by 5–16% compared to S. The results indicated that straw return to paddy fields exacerbated hypoxia and reducing conditions in the soil. SO90 achieved better effects than SO30 in alleviating the negative impact of straw return by supplying more oxygen, but the effects weakened over time and with soil depth.

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Soybean Root Growth in Response to Chemical, Physical, and Biological Soil Variations

Frontiers in Plant Science ◽

10.3389/fpls.2021.602569 ◽

2021 ◽

Vol 12 ◽

Author(s):

Mariele Müller ◽

Julia Renata Schneider ◽

Vilson Antônio Klein ◽

Eliardo da Silva ◽

José Pereira da Silva Júnior ◽

...

Keyword(s):

Microbial Biomass ◽

Root Growth ◽

Negative Impact ◽

Soil Depth ◽

Soil Surface ◽

Total Porosity ◽

Soil Layers ◽

Soybean Roots ◽

Biological Attributes ◽

High Concentrations

Environmental conditions affect crop yield, and water deficit has been highlighted by the negative impact on soybean grain production. Radicial growth in greater volume and depth can be an alternative to minimize losses caused by a lack of water. Therefore, knowledge of how soybean roots behave before the chemical, physical, and biological attributes of the soil can help establish managements that benefit in-depth root growth. The objective was to evaluate the growth of soybean roots in response to chemical, physical, and biological variations in the soil, in different soil locations and depths. Six experiments were conducted in different locations. Soil samples were collected every 5 cm of soil up to 60 cm of soil depth for chemical, physical, and biological analysis. The roots were collected every 5 cm deep up to 45 cm deep from the ground. The six sites presented unsatisfactory values of pH and organic matter, and presented phosphorus, potassium, and calcium at high concentrations in the first centimeters of soil depth. The total porosity of the soil was above 0.50 m3 m−3, but the proportion of the volume of macropores, micropores, and cryptopores resulted in soils with resistance to penetration to the roots. Microbial biomass was higher on the soil surface when compared to deeper soil layers, however, the metabolic quotient was higher in soil depth, showing that microorganisms in depth have low ability to incorporate carbon into microbial biomass. Root growth occurred in a greater proportion in the first centimeters of soil-depth, possibly because the soil attributes that favor the root growth is concentrated on the soil surface.

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Spatial variability in soybean associated with soil fertility variations in a no-tillage system

Australian Journal of Crop Science ◽

10.21475/ajcs.20.14.09.p2551 ◽

2020 ◽

pp. 1465-1472

Author(s):

Michel Esper Neto ◽

Evandro Antonio Minato ◽

Anderson Takashi Hara ◽

Silas Maciel de Oliveira ◽

Edner Betioli Junior ◽

...

Keyword(s):

Spatial Variability ◽

Soil Fertility ◽

Soil Depth ◽

Soil Layer ◽

Nutrient Losses ◽

Soybean Yield ◽

Soil Layers ◽

Tillage System ◽

Different Depths ◽

Kriging Maps

Understanding the spatial variability of soil fertility is necessary for preventing nutrient losses or excessive agricultural inputs. The aim of this research was to evaluate the spatial variability of the chemical characteristics of a Typic Hapludox cultivated with soybean for 110 days at different depths and the impacts of these characteristics on crop yield. Soil samples were collected at a total of 80 points in an area of 5000 m2 . The contents of P, Ca, Mg, S, Cu, Fe, Zn and Mn were analyzed, in addition to pH and H+Al. The data were evaluated through descriptive statistics and geostatistical tools, and kriging maps were made based on semivariogram adjustments. Most of the soil fertility variables showed moderate or strong spatial dependence. The statistical moments obtained for the distributions showed that the symmetry of the distributions allowed the use of geostatistics techniques. In general, the greater the soil depth was, the lower the nutrient levels were. The soybean yield range (29.5 m) was similar to the P range in the 0.0-0.20 m soil layer (29.2 m). P influenced the soybean yield the most, as expressed by the similarity between the two kriging maps. In regions with more phosphorus at deeper soil layers, higher soybean yields were obtained.

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THE VALUE OF SKELETAL MUSCLE MASS IN PREDICTING SHORT-TERM OUTCOMES OF SURGICAL TREATMENT FOR KLATSKIN TUMOR

Problems in oncology ◽

10.37469/0507-3758-2018-64-5-564-569 ◽

2018 ◽

Vol 64 (5) ◽

pp. 564-569

Author(s):

Yuriy Zharikov ◽

Tatyana Zharikova ◽

Vladimir Nikolenko

Keyword(s):

Skeletal Muscle ◽

Surgical Treatment ◽

Muscle Mass ◽

Skeletal Muscle Mass ◽

Negative Impact ◽

Treatment Algorithm ◽

Preoperative Treatment ◽

Klatskin Tumor ◽

Short Term ◽

Oncological Patients

The objective of this review study was to analyze the relationship between skeletal muscle mass and postoperative short-term outcomes morbidity in patients with Klatskin tumor who underwent surgical treatment. Low index skeletal muscle mass had a negative impact factor on postoperative morbidity following resection of Klatskin tumor and should therefore be considered as preoperative risk assessment. The further study of body composition in oncological patients allowed revealing the group of patients with high probability of postoperative complications and this factor needed to be added to future models predictive scale of short-term outcomes with the aim of making the most rational preoperative treatment algorithm.

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LYSIMETERS WITH RAINFALL AND SOIL WATER CONTROL

Hydrology Research ◽

10.2166/nh.1971.0006 ◽

1971 ◽

Vol 2 (2) ◽

pp. 79-92 ◽

Cited By ~ 17

Author(s):

K. J. KRISTENSEN ◽

H. C. ASLYNG

Keyword(s):

Soil Moisture Content ◽

Soil Depth ◽

Irrigation System ◽

Drainage System ◽

Soil Surface ◽

Trickle Irrigation ◽

Water Control ◽

Radiation Equipment ◽

Different Depths ◽

Growth Experiments

The lysimeter installation described comprises 36 concrete tanks each with a soil surface of 4 m2. The installation is useful for plant growth experiments under natural conditions involving different treatment combined with various controlled water supplies. The ground installation is at least 20 cm below the soil surface and tillage can be done with field implements. The lysimeter tanks are provided with a drainage system which can drain the soil at the bottom (100 cm depth) to a tension of up to 100 cm. A constant ground-water table at less than 100 cm soil depth can also be maintained. The soil moisture content at different depths is determined from an underground tunnel by use of gamma radiation equipment in metal tubes horizontally installed in the soil. Rainfall is prevented by a movable glass roof automatically operated and controlled by a special rain sensor. Water is applied to the soil surface with a special trickle irrigation system consisting of a set of plastic tubes for each lysimeter tank and controlled from the tunnel. Fertilizers in controlled amount can be applied with the irrigation water.

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Effects of different returning method combined with decomposer on decomposition of organic components of straw and soil fertility

Scientific Reports ◽

10.1038/s41598-021-95015-5 ◽

2021 ◽

Vol 11 (1) ◽

Author(s):

Xiao Wang ◽

Xuexin Wang ◽

Peng Geng ◽

Qian Yang ◽

Kun Chen ◽

...

Keyword(s):

Organic Carbon ◽

Soil Fertility ◽

Decomposition Rate ◽

Microbial Biomass Carbon ◽

No Tillage ◽

Short Term ◽

Straw Decomposition ◽

Short Period ◽

Straw Return ◽

Forms Of Carbon

AbstractIn view of the problems of low straw decomposition rates and reduced soil fertility in southern Liaoning, China, we investigated the effects of no-tillage mode (NT), deep loosening + deep rotary tillage mode (PT), rotary tillage mode (RT) and the addition of decomposing agent (the next is called a decomposer) (NT + S, PT + S, RT + S) on the decomposition proportion of straw, respectively, by using the nylon net bag method in combination with 365-day field plot experiments. The decomposition rules of cellulose, hemicellulose and lignin as well as the dynamics of soil organic carbon (SOC), soil microbial biomass carbon (MBC) and soil dissolved organic carbon (DOC) in straw returned to the field for 15, 35, 55, 75, 95, 145 and 365 days were analyzed. The results showed that in the short term, the decomposition of straw was better in both the rotray tillage and deep loosening + deep rotary modes than in the no-tillage mode, and the addition of decomposer significantly promoted the decomposition of straw and the release of carbon from straw, among them, the RT + S treatment had the highest straw decomposition proportion and carbon release proportion in all sampling periods. After a one year experimental cycle, the RT + S treatment showed the highest proportion of cellulose, hemicellulose and lignin decomposition with 35.49%, 84.23% and 85.50%, respectively, and soil SOC, MBC and DOC contents were also higher than the other treatments with an increase of 2.30 g kg−1, 14.22 mg kg−1 and 25.10 mg kg−1, respectively, compared to the pre-experimental soil. Our results show that in the short term, to accelerate the decomposition rate of returned straw and increase the content of various forms of carbon in soil, rotary tillage can be used to return the straw to the field, while also spraying straw decomposer on its surface. This experiment used a new straw decomposer rich in a variety of microorganisms, combined with the comparison of a variety of straw return modes, and in-depth study of straw decomposition effects of cellulose, hemicellulose and lignin. Thus, a scheme that can effectively improve the decomposition rate of straw and the content of various forms of organic carbon in soil within a short period of time was explored to provide theoretical support for the southern Liaoning.

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The interplay of gender, social context, and long-term unemployment effects on subjective health trajectories

BMC Public Health ◽

10.1186/s12889-021-10324-8 ◽

2021 ◽

Vol 21 (1) ◽

Author(s):

Laura Altweck ◽

Stefanie Hahm ◽

Holger Muehlan ◽

Tobias Gfesser ◽

Christine Ulke ◽

...

Keyword(s):

Life Satisfaction ◽

Social Context ◽

Negative Impact ◽

Subjective Health ◽

Short Term ◽

Self Rated Health ◽

Health Trajectories ◽

Lower Baseline ◽

Baseline Values

Abstract Background While a strong negative impact of unemployment on health has been established, the present research examined the lesser studied interplay of gender, social context and job loss on health trajectories. Methods Data from the German Socio-Economic Panel was used, which provided a representative sample of 6838 participants. Using latent growth modelling the effects of gender, social context (East vs. West Germans), unemployment (none, short-term or long-term), and their interactions were examined on health (single item measures of self-rated health and life satisfaction respectively). Results Social context in general significantly predicted the trajectories of self-rated health and life satisfaction. Most notably, data analysis revealed that West German women reported significantly lower baseline values of self-rated health following unemployment and did not recover to the levels of their East German counterparts. Only long-term, not short-term unemployment was related to lower baseline values of self-rated health, whereas, in relation to baseline values of life satisfaction, both types of unemployment had a similar negative effect. Conclusions In an economic crisis, individuals who already carry a higher burden, and not only those most directly affected economically, may show the greatest health effects.

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The impact of the COVID-19 outbreak on Chinese-listed tourism stocks

Financial Innovation ◽

10.1186/s40854-021-00240-6 ◽

2021 ◽

Vol 7 (1) ◽

Author(s):

Wenmin Wu ◽

Chien-Chiang Lee ◽

Wenwu Xing ◽

Shan-Ju Ho

Keyword(s):

Stock Returns ◽

Cultural Differences ◽

Stock Price ◽

Negative Impact ◽

Tourism Industry ◽

Regression Analyses ◽

Short Term ◽

Tourism Sector ◽

Event Study Method ◽

The Impact

AbstractThis research explored the effects of the coronavirus disease (COVID-19) outbreak on stock price movements of China’s tourism industry by using an event study method. The results showed that the crisis negatively impacted tourism sector stocks. Further quantile regression analyses supported the non-linear relationship between the government’s responses and stock returns. The results present that the resurgence of the virus in Beijing did bring about a short-term negative impact on the tourism industry. The empirical results can be used for future researchers to conduct a comparative study of cultural differences concerning government responses to the COVID-19.

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Effects of Short-Term Rice Straw Return on the Soil Microbial Community

Agriculture ◽

10.3390/agriculture11060561 ◽

2021 ◽

Vol 11 (6) ◽

pp. 561

Author(s):

Enze Wang ◽

Xiaolong Lin ◽

Lei Tian ◽

Xinguang Wang ◽

Li Ji ◽

...

Keyword(s):

Microbial Community ◽

Rice Straw ◽

Paddy Soil ◽

Soil Microbial Community ◽

Short Term ◽

Soil Microbial ◽

Microbial Network ◽

Straw Return ◽

Bacteria And Fungi ◽

Main Factor

Rice straw is a byproduct of agricultural production and an important agricultural resource. However, rice straw has not yet been effectively used, and incorrect treatment methods (such as burning in the field) can cause serious damage to the environment. Studies have shown that straw returning is beneficial to soil, but there have been few studies focused on the effect of the amount of short-term straw returned on the soil microbial community. This study evaluates 0%, 50%, 75%, and 100% rice straw returned to the field on whether returning different amounts of straw in the short term would affect the diversity and composition of the soil microbial community and the correlation between bacteria and fungi. The results show that the amount of straw returned to the field is the main factor that triggers the changes in the abundance and composition of the microbial community in the paddy soil. A small amount of added straw (≤ 50% straw added) mainly affects the composition of the bacterial community, while a larger amount of added straw (> 50% straw added) mainly affects the composition of the fungal community. Returning a large amount of straw increases the microbial abundance related to carbon and iron cycles in the paddy soil, thus promoting the carbon and iron cycle processes to a certain extent. In addition, network analysis shows that returning a large amount of straw also increases the complexity of the microbial network, which may encourage more microbes to be niche-sharing and comprehensively improve the ecological environment of paddy soil. This study may provide some useful guidance for rice straw returning in northeast China.

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Impact of Thermotherapy and Short-Term Storage on Quercus robur L. Acorn Mycobiota and Germination

Forests ◽

10.3390/f12050528 ◽

2021 ◽

Vol 12 (5) ◽

pp. 528

Author(s):

Jelena Kranjec Orlović ◽

Damir Drvodelić ◽

Marko Vukelić ◽

Matea Rukavina ◽

Danko Diminić ◽

...

Keyword(s):

Natural Regeneration ◽

Fungal Diversity ◽

Quercus Robur ◽

Negative Impact ◽

Storage Conditions ◽

Short Term ◽

Isolation Frequency ◽

Short Term Storage ◽

Penicillium Spp ◽

Term Storage

When natural regeneration of Quercus robur stands is hampered by an insufficient acorn yield, human assisted sowing of acorns collected in non-affected stands and stored for some period of time is performed. To inhibit the development of fungi and acorn deterioration during storage, thermotherapy is usually applied by submerging acorns for 2.5 h in water heated to 41 °C. This research aimed to test the effect of four thermotherapy treatments of different durations and/or applied temperatures as well as short-term storage at −1 °C or 3 °C on acorn internal mycobiota and germination. Fungal presence in cotyledons was analyzed in 450 acorns by isolation of mycelia on artificial media, followed by a DNA-based identification. Germination of 2000 acorns was monitored in an open field trial. Thermotherapy significantly decreased fungal diversity, while storage at 3 °C increased the isolation frequency of several fungi, mainly Penicillium spp. The most frequently isolated fungi did not show a negative impact on acorn germination after short-term storage. The study confirmed the efficiency of thermotherapy in the eradication of a part of acorn internal mycobiota, but also its effect on the proliferation of fast-colonizing fungi during storage. However, the latter showed to be more stimulated by storage conditions, specifically by storage at 3 °C.

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THREATS TO NATIONAL SECURITY OF RUSSIA IN THE CONTEXT OF A HYBRID WAR

Central Russian Journal of Social Sciences ◽

10.22394/2071-2367-2021-16-3-109-130 ◽

2021 ◽

Vol 16 (3) ◽

pp. 109-130

Author(s):

A.S. MAKSIMOV ◽

Keyword(s):

Synergistic Effect ◽

National Security ◽

Negative Impact ◽

Short Term ◽

Economic Information ◽

Hybrid Threats ◽

Hybrid War ◽

Political Economic ◽

Verbal Model

This article is devoted to identifying and characterizing the threat to national security of Russian Federation in the context of a hybrid war. The main aim of the study is to assume that the huge problem for national security of Russia today is the threat of a hybrid nature. This paper proposes the author's classification of hybrid threats, which made it possible to distinguish five functional groups of threats («triads») ‒ in the spiritual and socio-cultural, military-political, economic, information and international legal spheres. The specificity of the «triads» is that each of the three elements of the «triad» is capable of producing the appearance of the second and third elements of the «triad» and maintaining their activity. A variant of ranking «triads» according to the level of their threat intensity is presented, the rates of their intensification in the short term were determined. According to the author's conclusions, the synchronous activity of the «triads» creates a synergistic effect, exerting a complicated negative impact on the state of national security of Russia. The novelty of the research, the results of which are presented in the article, are the classification of hybrid threats and the verbal model of the functioning of the «triads» of threats. The findings of the study can contribute to the development of effective techniques and strategies for countering hybrid threats to national security of Russia.

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