Effect of Pasture Management System Change on In-Season Inorganic Nitrogen Pools and Heterotrophic Microbial Communities

It has been assumed that the system of long-term pasture management exerts a significant impact on the soil microorganisms count, subsequently affecting the availability of mineral nitrogen (Nmin). This hypothesis was tested in a three-year experiment on a long-term pasture with two distinct systems of grass sward management, i.e., grazing and mowing. Mowing significantly increased the microorganisms count by 13%, 28%, 86%, and 2% for eubacteria (EU), actinobacteria (AC), molds (MO), and Azotobacter (AZ), respectively. The main reason was drought in 2006, which resulted in the domination of Dactylis glomerata L. in the grass sward, instead of Lolimum perenne L. and Poa pratensis L. The content of Nmin decreased through the vegetative growing season, reaching its lowest value after the 3rd grazing cycle. The impact of microorganisms on the Nmin pools increased in the order: molds < eubacteria < actinobacteria. The count of actinobacteria in the alkaline organic soil increased in response to drought, contribution of Dactylis glomerata L. in the sward, and the shortage of available phosphorus. The sound pasture management system is possible by introducing alternate grazing and mowing cycles. The core of sustainability is the enhanced activity of actinobacteria after changing the system from grazed into mowed.

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The effects of long-term exposures to SO2 and NO2 pollution on the growth of Dactylis glomerata L. and Poa pratensis L.

Environmental Pollution (1970) ◽

10.1016/0013-9327(79)90020-x ◽

1979 ◽

Vol 18 (4) ◽

pp. 249-258 ◽

Cited By ~ 54

Author(s):

T.W. Ashenden

Keyword(s):

Poa Pratensis ◽

Dactylis Glomerata ◽

Dactylis Glomerata L ◽

No2 Pollution

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Nutrient retention behind a tropical mega-dam: a case study of the Sardar Sarovar Dam, India

SN Applied Sciences ◽

10.1007/s42452-020-04118-7 ◽

2021 ◽

Vol 3 (1) ◽

Author(s):

Harish Gupta ◽

S. Kiran Kumar Reddy ◽

Mounika Chiluka ◽

Vamshikrishna Gandla

Keyword(s):

Arabian Sea ◽

Inorganic Nitrogen ◽

Nutrient Retention ◽

Significant Loss ◽

N Removal ◽

Narmada River ◽

Sardar Sarovar ◽

The Impact

AbstractIn this study, we demonstrate the impact of the construction of a mega-dam on the nutrient export regime of a large tropical river into the Arabian Sea. Long-term (11 years) fortnight nutrient parameters, upstream and downstream to Sardar Sarovar (SS) Dam, were examined to determine the periodical change in nutrient fluxes from the Narmada River, India. During this 11-year period, the average discharge of the Narmada River upstream to Rajghat (35.3 km3 year−1) was higher than that of downstream at Garudeshwar (33.9 km3 year−1). However, during the same period, the suspended sediment load was reduced by 21 million tons (MT) from 37.9 MT at Rajghat to 16.7 MT at Garudeshwar. Similarly, mean concentrations of dissolved silica (DSi) reduced from 470 (upstream) to 214 µM (downstream), dissolved inorganic phosphate (DIP) from 0.84 to 0.38 µM, and dissolved inorganic nitrogen (DIN) from 43 to 1.5 µM. It means that about 54%, 55%, and 96% flux of DSi, DIP, and DIN retained behind the dam, respectively. The estimated denitrification rate (80,000 kg N km−2 year−1) for the reservoir is significantly higher than N removal by lentic systems, globally. We hypothesize that processes such as biological uptake and denitrification under anoxic conditions could be a key reason for the significant loss of nutrients, particularly of DIN. Finally, we anticipated that a decline in DIN fluxes (by 1.13 × 109 mol year−1) from the Narmada River to the Arabian Sea might reduce the atmospheric CO2 fixation by 7.46 × 109 mol year−1.

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Soil carbon dynamics under different cropping and pasture management in temperate Australia: Results of three long-term experiments

Soil Research ◽

10.1071/sr10185 ◽

2011 ◽

Vol 49 (4) ◽

pp. 320 ◽

Cited By ~ 84

Author(s):

K. Y. Chan ◽

M. K. Conyers ◽

G. D. Li ◽

K. R. Helyar ◽

G. Poile ◽

...

Keyword(s):

Steady State ◽

Management Practices ◽

Agricultural Soils ◽

Soil Depth ◽

Crop Productivity ◽

Wagga Wagga ◽

Continuous Cropping ◽

Pasture Management ◽

The Impact

In addition to its important influence on soil quality and therefore crop productivity, soil organic carbon (SOC) has also been identified as a possible C sink for sequestering atmospheric carbon dioxide. Limited data are available on the impact of management practices on the rate of SOC change in agricultural soils in Australia. In this paper, results of three long-term trials (13–25 years) located near Wagga Wagga in temperate Australia were used to assess C dynamics under different tillage and stubble management practices, and under cropping intensities in pasture/crop rotations. Experimental results confirm the importance of management practices and pasture in determining first the steady-state SOC concentrations that are characteristic of given rotations and crop management systems, and second the rates of change of SOC concentrations as they approach steady-state concentrations in agricultural soils of this agro-ecological zone. A long-term crop/pasture experiment at a site with initial high SOC showed that the rate of SOC change in different treatments ranged from –278 to +257 kg C/ha.year over 0–0.3 m soil depth. Under continuous cropping, even under conservation agriculture practices of no-tillage, stubble retention, and crop rotation, the high initial SOC stock (0–0.3 m) present after a long-term pasture phase was, at best, maintained but tended to decrease with increased tillage or stubble burning practices. The effect of tillage was greater than that of stubble management. Increases in SOC were observed only in rotations incorporating a pasture phase. Our results suggest that improved soil nutrient and grazing management of permanent pasture can lead to an increase of 500–700 kg C/ha.year where the initial SOC concentrations are well below steady-state concentrations that could be expected after long periods of improved management. No difference was found between perennial pasture and annual pasture to the depth measured (0–0.3 m). Our results suggest that pasture holds the key to maintaining, and even increasing, SOC under crop/pasture in this environment.

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Nitrogen content in plant biomass from subterranean clover (Trifolium subterraneum L.) and cocksfoot (Dactylis glomerata L.) grown under different inorganic nitrogen supply

Ratarstvo i povrtarstvo ◽

10.5937/ratpov52-8930 ◽

2015 ◽

Vol 52 (3) ◽

pp. 114-119

Author(s):

Viliana Vasileva ◽

Konstantina Kocheva ◽

Janet Mincheva ◽

Georgi Georgiev ◽

Anna Ilieva ◽

...

Keyword(s):

Nitrogen Content ◽

Plant Biomass ◽

Inorganic Nitrogen ◽

Dactylis Glomerata ◽

Subterranean Clover ◽

Trifolium Subterraneum ◽

Nitrogen Supply ◽

Dactylis Glomerata L

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Bioaccumulation of nitrogen and phosphorus by lawn plants in urban environment

Herald of Tver State University. Series: Biology and Ecology ◽

10.26456/vtbio162 ◽

2020 ◽

pp. 86-94

Author(s):

Марина Григорьевна Половникова ◽

Ольга Леонидовна Воскресенская ◽

Елена Александровна Алябышева

Keyword(s):

Urban Environment ◽

Phosphorus Content ◽

Poa Pratensis ◽

Dactylis Glomerata ◽

Middle Aged ◽

Nitrogen And Phosphorus ◽

Dactylis Glomerata L

В условиях городской среды в биомассе онтогенетических групп газонных растений (ежа сборная, мятлик луговой) определяли содержание азота и фосфора, а также биоаккумулятивную способность ценопопуляций видов. В работе использовались растения трех возрастных состояний: виргинильные (v), средневозрастные генеративные (g2) и субсенильные (ss). По мере усиления загрязнения среды и в ходе онтогенеза уменьшалось содержание общего азота и общего фосфора в биомассе газонных растений. При оценке биоаккумулятивной способности ценопопуляций изученных видов установлено, что ценопопуляции ежи сборной накапливали большее количество общего азота и общего фосфора во всех местообитаниях. In the urban environment, the biomass of ontogenetic groups of lawn plants (Dactylis glomerata L., Poa pratensis L.) was determined by the content of nitrogen and phosphorus, as well as the bioaccumulative ability of species coenopopulations. We used plants of three ages: virginil (v), middle-aged generative (g2), and subsenile (ss). As pollution increased and during ontogenesis, the nitrogen and phosphorus content in the biomass of lawn plants decreased. In assessing the bioaccumulative capacity of the coenopopulations of the studied species, it was found that the coenopopulations of Dactylis glomerata accumulated more nitrogen and phosphorus in all habitats.

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Soil Chemical and Microbiological Properties Are Changed by Long-Term Chemical Fertilizers That Limit Ecosystem Functioning

Microorganisms ◽

10.3390/microorganisms8050694 ◽

2020 ◽

Vol 8 (5) ◽

pp. 694 ◽

Cited By ~ 2

Author(s):

Yong-Chao Bai ◽

Ying-Ying Chang ◽

Muzammil Hussain ◽

Bin Lu ◽

Jun-Pei Zhang ◽

...

Keyword(s):

Plant Growth ◽

Ammonium Nitrogen ◽

Available Phosphorus ◽

Chemical Fertilizers ◽

Nutrient Mobilization ◽

Organic Cultivation ◽

Fertilized Soil ◽

The Impact ◽

Microbiological Properties

Although the effects of fertilization and microbiota on plant growth have been widely studied, our understanding of the chemical fertilizers to alter soil chemical and microbiological properties in woody plants is still limited. The aim of the present study is to investigate the impact of long-term application of chemical fertilizers on chemical and microbiological properties of root-associated soils of walnut trees. The results show that soil organic matter (OM), pHkcl, total nitrogen (TN), nitrate-nitrogen (NO3−), and total phosphorus (TP) contents were significantly higher in non-fertilized soil than after chemical fertilization. The long-term fertilization led to excessive ammonium-nitrogen (NH4+) and available phosphorus (AP) residues in the cultivated soil, among which NH4+ resulted in soil acidification and changes in bacterial community structure, while AP reduced fungal diversity. The naturally grown walnut trees led to an enrichment in beneficial bacteria such as Burkholderia, Nitrospira, Pseudomonas, and Candidatus_Solibacter, as well as fungi, including Trichoderma, Lophiostoma, Phomopsis, Ilyonectria, Purpureocillium, Cylindrocladiella, Hyalorbilia, Chaetomium, and Trichoglossum. The presence of these bacterial and fungal genera that have been associated with nutrient mobilization and plant growth was likely related to the higher soil OM, TN, NO3−, and TP contents in the non-fertilized plots. These findings highlight that reduced chemical fertilizers and organic cultivation with beneficial microbiota could be used to improve economic efficiency and benefit the environment in sustainable agriculture.

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Socio-political aspects of the processes of improvement of the system of military-political administration in providing national security of the Russian Federation

National Security and Strategic Planning ◽

10.37468/2307-1400-2020-2-29-35 ◽

2020 ◽

Vol 2020 (2) ◽

pp. 29-35

Author(s):

V. Tolstykh

Keyword(s):

National Security ◽

Russian Federation ◽

Management System ◽

Social Situation ◽

The World ◽

Political Management ◽

The Russian Federation ◽

The Military ◽

The Impact

The article discusses the impact of the crisis occurring recently in the world, including the COVID-19 coronavirus pandemic related to the state of the military-political management system of the Russian Federation while ensuring the national security of the Russian Federation. The author analyzes the ability of the system to withstand modern dangers and threats aimed at destabilizing the domestic political and social situation and identifies the most important areas for improving military-political management in the medium and long term.

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Soil bacterial biodiversity is driven by long-term pasture management, poultry litter, and cattle manure inputs

PeerJ ◽

10.7717/peerj.7839 ◽

2019 ◽

Vol 7 ◽

pp. e7839 ◽

Cited By ~ 5

Author(s):

Yichao Yang ◽

Amanda J. Ashworth ◽

Jennifer M. DeBruyn ◽

Cammy Willett ◽

Lisa M. Durso ◽

...

Keyword(s):

Poultry Litter ◽

Soil Health ◽

Soil Microbial Communities ◽

Cattle Manure ◽

Soil Microbiome ◽

Pasture Management ◽

Soil Microbial Community Structure ◽

Soil Microbial ◽

The Impact

Soil microorganisms are important for maintaining soil health, decomposing organic matter, and recycling nutrients in pasture systems. However, the impact of long-term conservation pasture management on soil microbial communities remains unclear. Therefore, soil microbiome responses to conservation pasture management is an important component of soil health, especially in the largest agricultural land-use in the US. The aim of this study was to identify soil microbiome community differences following 13-years of pasture management (hayed (no cattle), continuously grazed, rotationally grazed with a fenced, un-grazed and unfertilized buffer strip, and a control (no poultry litter or cattle manure inputs)). Since 2004, all pastures (excluding the control) received annual poultry litter at a rate of 5.6 Mg ha−1. Soil samples were collected at a 0–15 cm depth from 2016–2017 either pre or post poultry litter applications, and bacterial communities were characterized using Illumina 16S rRNA gene amplicon sequencing. Overall, pasture management influenced soil microbial community structure, and effects were different by year (P < 0.05). Soils receiving no poultry litter or cattle manure had the lowest richness (Chao). Continuously grazed systems had greater (P < 0.05) soil community richness, which corresponded with greater soil pH and nutrients. Consequently, continuously grazed systems may increase soil diversity, owing to continuous nutrient-rich manure deposition; however, this management strategy may adversely affect aboveground plant communities and water quality. These results suggest conservation pasture management (e.g., rotationally grazed systems) may not improve microbial diversity, albeit, buffer strips were reduced nutrients and bacterial movement as evident by low diversity and fertility in these areas compared to areas with manure or poultry litter inputs. Overall, animal inputs (litter or manure) increased soil microbiome diversity and may be a mechanism for improved soil health.

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Temporal changes in nutrients in a deep oligomictic lake: the role of external loads versus internal processes

Journal of Limnology ◽

10.4081/jlimnol.2021.2051 ◽

2021 ◽

Vol 80 (3) ◽

Author(s):

Michela Rogora ◽

Martina Austoni ◽

Rossana Caroni ◽

Paola Giacomotti ◽

Lyudmila Kamburska ◽

...

Keyword(s):

Water Column ◽

Total Phosphorus ◽

Inorganic Nitrogen ◽

Lake Maggiore ◽

Deep Mixing ◽

Long Term Study ◽

Mixing Patterns ◽

The Impact ◽

External Loads

The impact of climate change on stratification and mixing patterns has important effects on nutrient availability and plankton dynamics in deep lakes. We demonstrate this in a long-term study of Lake Maggiore, a deep oligomictic lake located in the subalpine lake district in Northern Italy. Studies on physical, chemical and biological features of the lake have been performed continuously since the 1980s. The lake recovered from eutrophication in response to a reduction of catchment nutrient loads and reached a stable oligotrophic status by the end of the 1990s, with average total phosphorus concentrations in the water column around 10 µg L-1. However, both reactive and total phosphorus have slightly increased since 2010, leading to a shift in the lake trophic state towards mesotrophy. The increase in phosphorus has been limited to the hypolimnetic layers, concentrations being fairly stable or decreasing in the epilimnion. Reactive silica also progressively increased in the hypolimnion, while nitrate and total nitrogen concentrations have steadily decreased in both deep and surface layers, especially in the summer period. These changes were assessed in relation to catchment loads, atmospheric deposition and climate-related variations in stratification and mixing patterns and in nutrient retention. Long-term changes in primary production, represented by chlorophyll levels, and biovolume of the main algal groups were also considered. During the eutrophication period and until the 1990s, in-lake phosphorus concentrations were tightly related to external loads; successively, phosphorus and its vertical distribution up the water column became more controlled by internal processes, in particular by stratification and mixing regime. An increase of thermal stability and a reduced frequency and intensity of deep mixing events has fostered oxygen depletion and phosphorus and silica accumulation in the hypolimnion. Another consequence of reduced deep mixing events, has been a reduction in nutrient replenishment of the upper layers at spring mixing. External loads are still the main driver of change for nitrogen compounds: the decrease in the atmospheric load of nitrogen that occurred in the Lake Maggiore area over the last decade, as an effect of reduced nitrogen emissions, has caused decreasing concentration of inorganic nitrogen in the lake. However, the phytoplankton community changes observed might also play a role in nitrogen dynamics, particularly in the nitrate minima observed during summer in recent years.

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