scholarly journals Increased seed carbohydrate reserves associated with domestication influence the optimal seminal root number of Zea mays

2020 ◽  
Author(s):  
Alden C. Perkins ◽  
Jonathan P. Lynch
Keyword(s):  
Zea Mays ◽  
Optimal Number ◽  
Seminal Root ◽  
Root Number ◽  
Nitrogen And Phosphorus ◽  
Southern Mexico ◽  
Carbohydrate Reserves ◽  
Maize Landrace ◽  
Seminal Roots ◽  
The Impact

AbstractBackground and AimsDomesticated maize (Zea mays ssp. mays) generally forms between two and six seminal roots, while its wild ancestor, Mexican annual teosinte (Zea mays ssp. parviglumis), typically lacks seminal roots. Maize also produces larger seeds than teosinte, and it generally has higher growth rates as a seedling. Maize was originally domesticated in the tropical soils of southern Mexico, but it was later brought to the Mexican highlands before spreading to other parts of the continent, where it experienced different soil resource constraints. The aims of this study were to understand the impact of increased seminal root number on seedling nitrogen acquisition and to model how differences in maize and teosinte phenotypes might have contributed to increased seminal root number in domesticated maize.MethodsSeedling root architectural models of a teosinte accession and a maize landrace were constructed by parameterizing the functional-structural plant model OpenSimRoot using plants grown in mesocosms. Seedling growth was simulated in a low-phosphorus environment, multiple low-nitrogen environments, and at variable planting densities. Models were also constructed to combine individual components of the maize and teosinte phenotypes.Key ResultsSeminal roots contributed about 35% of the nitrogen and phosphorus acquired by maize landrace seedlings in the first 25 days after planting. Increased seminal root number improved plant N acquisition under low-N environments with varying precipitation patterns, fertilization rates, soil textures, and planting densities. Models suggested that the optimal number of seminal roots for nutrient acquisition in teosinte is constrained by its limited seed carbohydrate reserves.ConclusionsSeminal roots can improve the acquisition of both nitrogen and phosphorus in maize seedlings, and the increase in seed size associated with maize domestication may have facilitated increased seminal root number.

AMOUNT AND STRUCTURE OF THE BIOLOGICAL FERTILITY OF SOYA, DEPENDING ON THE SYSTEM OF MAIN TILLAGE OF SOIL AND MEASURES TO OPTIMIZE NUTRITION MODE

2020 ◽  
Author(s):  
M. Novokhatskyi ◽  
◽  
V. Targonya ◽  
T. Babinets ◽  
O. Gorodetskyi ◽  
...  
Keyword(s):  
Field Experiments ◽  
Optimal Number ◽  
Soil Tillage ◽  
Forest Steppe ◽  
Biological Productivity ◽  
Tillage Systems ◽  
Application Rates ◽  
Tillage System ◽  
Biological Yield ◽  
The Impact

Aim. Assessment of the impact of the most common systems of basic tillage and biological methods of optimization of nutrition regimes on the realization of the potential of grain productivity of soybean in the Forest-Steppe of Ukraine. Methods. The research used general scientific (hypothesis, experiment, observation) and special (field experiment, morphological analysis) methods Results. The analysis of the results of field experiments shows that the conservation system of soil cultivation, which provided the formation of 27.6 c/ha of grain, is preferable by the level of biological yield of soybean. The use of other systems caused a decrease in the biological yield level: up to 26.4 c/ha for the use of the traditional system, up to 25.3 c/ha for the use of mulching and up to 23.0 c/ha for the use of the mini-till. With the use of Groundfix, the average biological yield of soybean grain increases to 25.6 c / ha for application rates of 5 l/ha, and to 28.2 c/ha for application rates of 10 l/ha when control variants (without the use of the specified preparation) an average of 22.6 c/ha of grain was formed with fluctuations in soil tillage systems from 21.0 (mini-bodies) to 25.8 c/ha (traditional).The application of Groundfix (10 l/ha) reduced the seed abortion rate from 11.0% (average without biofertilizer variants) to 8.0%, forming the optimal number of stem nodes with beans, increasing the attachment height of the lower beans and improving other indicators of biological productivity soybeans. Conclusions. It has been found that the use of the canning tillage system generates an average of 27.6 cent soybean grains, which is the highest indicator among the main tillage systems within the scheme of our research. The use of Groundfix caused a change in this indicator: if the variants with a conservative system of basic tillage without the use of biological preparation (control) were formed on average 24.1 c/ha, the use of Ground Licks caused the increase of biological productivity up to 29.4 c/ha, and at a dose of 10 l/ha biological yield was 32.2 c/ha. It was found that both the use of Groundfix and the basic tillage system influenced the elements of the yield structure: the density of the plants at the time of harvest depended more on the tillage system than on the use of Groundfix; the use of Groundfix and increasing its dose within the scheme of our studies positively reflected on the density of standing plants; the height of attachment of the lower beans and reduced the abortion of the seeds.

Heterotrophic Kinetic Parameter Estimation for Enhanced Biological Phosphorus Removal Processes Operated in Conventional and Membrane-Assisted Modes

2006 ◽  
Vol 41 (1) ◽  
pp. 72-83 ◽  
Author(s):  
Zhe Zhang ◽  
Eric R. Hall
Keyword(s):  
Parameter Estimation ◽  
Phosphorus Removal ◽  
Growth Yield ◽  
Pilot Scale ◽  
Enhanced Biological Phosphorus Removal ◽  
Biological Phosphorus Removal ◽  
Nitrogen And Phosphorus ◽  
Parameter Values ◽  
The Impact ◽  
Biological Phosphorus

Abstract Parameter estimation and wastewater characterization are crucial for modelling of the membrane enhanced biological phosphorus removal (MEBPR) process. Prior to determining the values of a subset of kinetic and stoichiometric parameters used in ASM No. 2 (ASM2), the carbon, nitrogen and phosphorus fractions of influent wastewater at the University of British Columbia (UBC) pilot plant were characterized. It was found that the UBC wastewater contained fractions of volatile acids (SA), readily fermentable biodegradable COD (SF) and slowly biodegradable COD (XS) that fell within the ASM2 default value ranges. The contents of soluble inert COD (SI) and particulate inert COD (XI) were somewhat higher than ASM2 default values. Mixed liquor samples from pilot-scale MEBPR and conventional enhanced biological phosphorus removal (CEBPR) processes operated under parallel conditions, were then analyzed experimentally to assess the impact of operation in a membrane-assisted mode on the growth yield (YH), decay coefficient (bH) and maximum specific growth rate of heterotrophic biomass (µH). The resulting values for YH, bH and µH were slightly lower for the MEBPR train than for the CEBPR train, but the differences were not statistically significant. It is suggested that MEBPR simulation using ASM2 could be accomplished satisfactorily using parameter values determined for a conventional biological phosphorus removal process, if MEBPR parameter values are not available.

Fish farming in Denmark: environmental impact of regulative legislation

1995 ◽  
Vol 31 (10) ◽  
pp. 73-84 ◽  
Author(s):  
T. M. Iversen
Keyword(s):  
Organic Matter ◽  
Environmental Impact ◽  
Freshwater Fish ◽  
Aquatic Environment ◽  
Action Plan ◽  
Fish Farming ◽  
Fish Farms ◽  
Nitrogen And Phosphorus ◽  
Local Impact ◽  
The Impact

The main environmental problems associated with fish farming in Denmark are attributable to the dam, the “dead reach” and nutrient and organic matter discharge. The environmental regulation of fish farming in Denmark started with the Environmental Protection Act of 1974, the Statutory Order of 1985 forbidding wet feed, and the Action Plan on the Aquatic Environment of 1987. In the case of freshwater fish farms, the latter was implemented through the measures stipulated in the 1989 Statutory Order on Fish Farms. The impact of Danish legislative measures to reduce and regulate the environmental effects of freshwater fish farms can be summarized as follows: - the number of fish farms has been reduced from about 800 in 1974 to about 500 at present; - production has tripled since 1974 and has been stable since 1989; - a change from wet to dry feed has reduced the environmental impact of the farms; - the national goals of the Action Plan on the Aquatic Environment of 1987 for reducing fish farm discharges of organic matter, nitrogen and phosphorus have been fulfilled. The main remaining problems are that: - the local impact of fish farms on downstream stream quality is still much too high in about 15% of cases; - the problem of the passage of migrating invertebrates and fish is still unsolved at some farms; - the problems posed by “dead reaches” are still unsolved. It is concluded that sustainable fish farming is possible in Denmark, but with the present technology production will have to be significantly reduced.

scholarly journals Quantifying the Impact of a Tsunami on Data-Driven Earthquake Relief Zone Planning in Los Angeles County via Multivariate Spatial Optimization

Geosciences ◽  
2021 ◽  
Vol 11 (2) ◽  
pp. 99 ◽  
Author(s):  
Yueqi Gu ◽  
Orhun Aydin ◽  
Jacqueline Sosa
Keyword(s):  
Los Angeles ◽  
A Priori ◽  
Safety Data ◽  
Spatial Optimization ◽  
Optimal Number ◽  
Multidisciplinary Optimization ◽  
Data Driven ◽  
Fault System ◽  
Design Data ◽  
The Impact

Post-earthquake relief zone planning is a multidisciplinary optimization problem, which required delineating zones that seek to minimize the loss of life and property. In this study, we offer an end-to-end workflow to define relief zone suitability and equitable relief service zones for Los Angeles (LA) County. In particular, we address the impact of a tsunami in the study due to LA’s high spatial complexities in terms of clustering of population along the coastline, and a complicated inland fault system. We design data-driven earthquake relief zones with a wide variety of inputs, including geological features, population, and public safety. Data-driven zones were generated by solving the p-median problem with the Teitz–Bart algorithm without any a priori knowledge of optimal relief zones. We define the metrics to determine the optimal number of relief zones as a part of the proposed workflow. Finally, we measure the impacts of a tsunami in LA County by comparing data-driven relief zone maps for a case with a tsunami and a case without a tsunami. Our results show that the impact of the tsunami on the relief zones can extend up to 160 km inland from the study area.

Monitoring of small rock pools reveals differential effects of chronic anthropogenic disturbance on birds and mammals in the Calakmul region, southern Mexico

2021 ◽  
pp. 1-10
Author(s):  
Carlos M. Delgado-Martínez ◽  
Fredy Alvarado ◽  
Melanie Kolb ◽  
Eduardo Mendoza
Keyword(s):  
Species Richness ◽  
Anthropogenic Disturbance ◽  
Forest Cover ◽  
Biosphere Reserve ◽  
Bird Diversity ◽  
Small Scale ◽  
Rock Pools ◽  
Southern Mexico ◽  
Wildlife Species ◽  
The Impact

Abstract Great attention has been drawn to the impacts of habitat deforestation and fragmentation on wildlife species richness. In contrast, much less attention has been paid to assessing the impacts of chronic anthropogenic disturbance on wildlife species composition and behaviour. We focused on natural small rock pools (sartenejas), which concentrate vertebrate activity due to habitat’s water limitation, to assess the impact of chronic anthropogenic disturbance on the species richness, diversity, composition, and behaviour of medium and large-sized birds and mammals in the highly biodiverse forests of Calakmul, southern Mexico. Camera trapping records of fauna using sartenejas within and outside the Calakmul Biosphere Reserve (CBR) showed that there were no effects on species richness, but contrasts emerged when comparing species diversity, composition, and behaviour. These effects differed between birds and mammals and between species: (1) bird diversity was greater outside the CBR, but mammal diversity was greater within and (2) the daily activity patterns of birds differed slightly within and outside the CBR but strongly contrasted in mammals. Our study highlights that even in areas supporting extensive forest cover, small-scale chronic anthropogenic disturbances can have pervasive negative effects on wildlife and that these effects contrast between animal groups.

A proposed sustainable BNR plant with the emphasis on recovery of COD and phosphate

2003 ◽  
Vol 48 (1) ◽  
pp. 77-85 ◽  
Author(s):  
X.-D. Hao ◽  
M.C.M. van Loosdrecht
Keyword(s):  
Wastewater Treatment ◽  
Municipal Wastewater ◽  
Water Environment ◽  
Pilot Scale ◽  
Ammonium Oxidation ◽  
Municipal Wastewater Treatment ◽  
Nitrogen And Phosphorus ◽  
Water Problems ◽  
Sustainable Wastewater Treatment ◽  
The Impact

Water problems have to be solved in an integrated way, and sustainability has become a major issue. For this reason, developing more sustainable wastewater treatment processes is needed. New discoveries and good understanding on microbial conversions of nitrogen and phosphorus make more sustainable processes possible. New options for decentralized sustainable sanitation are generally compared to conventional sewage systems, we think that for a proper comparison also innovative centralized treatment schemes should be evaluated. In this article, a more sustainable WWTP is proposed for municipal wastewater treatment, mainly based on the principles of denitrifying dephosphatation and anaerobic ammonium oxidation (ANAMMOX). The proposed system consists of a first stage of the A/B process in which maximal sludge production is achieved. In this way, COD is regained as sludge for methanation. The following BCFS® and CANON processes can remove N and P with minimal or no COD need. As a potential fertiliser, struvite can easily be removed from the sludge water by adding magnesium compounds. A case study is done on the basis of the mass balance over the proposed plant. The effluent from the system has a good quality to be recycled. This could also make a contribution to meeting the world's water needs and lessening the impact on the world's water environment. Since all the separate units are already applied or tested on pilot-scale, no problems for technical implementation are foreseen.

scholarly journals Graphene-Modulated Removal Performance of Nitrogen and Phosphorus Pollutants in a Sequencing Batch Chlorella Reactor

Materials ◽  
2018 ◽  
Vol 11 (11) ◽  
pp. 2181 ◽  
Author(s):  
Gonghan Xia ◽  
Wenlai Xu ◽  
Qinglin Fang ◽  
Zishen Mou ◽  
Zhicheng Pan
Keyword(s):  
Optical Microscopy ◽  
Sewage Treatment ◽  
Ammonia Nitrogen ◽  
Pollutant Removal ◽  
Plate Count ◽  
Nitrogen And Phosphorus ◽  
Removal Rates ◽  
Practical Support ◽  
Plate Count Method ◽  
The Impact

In this work, the influence of graphene on nitrogen and phosphorus in a batch Chlorella reactor was studied. The impact of graphene on the removal performance of Chlorella was investigated in a home-built sewage treatment system with seven identical sequencing batch Chlorella reactors with graphene contents of 0 mg/L (T1), 0.05 mg/L (T2), 0.1 mg/L (T3), 0.2 mg/L (T4), 0.4 mg/L (T5), 0.8 mg/L (T6) and 10 mg/L (T7). The influence of graphene concentration and reaction time on the pollutant removal performance was studied. The malondialdehyde (MDA) and total superoxide dismutase (SOD) concentrations in each reactor were measured, and optical microscopy and scanning electron microscopy (SEM) characterizations were performed to determine the related mechanism. The results show that after 168 h, the total nitrogen (TN), ammonia nitrogen (AN) and total phosphorus (TP) removal rates of reactors T1–T7 become stable, and the TN, AN and TP removal rates were gradually reduced with increasing graphene concentration. At 96 h, the concentrations of both MDA and SOD in T1–T7 gradually increased as the graphene concentration increased. In optical microscopy and SEM measurements, it was found that graphene was adsorbed on the surface of Chlorella, and entered Chlorella cells, deforming and reducing Chlorella. Through the blood plate count method, we estimated an average Chlorella reduction of 16%. According to the water quality and microscopic experiments, it can be concluded that the addition of graphene causes oxidative damage to microalgae and destruction of the Chlorella cell wall and cell membrane, inhibiting the nitrogen and phosphorus removal in Chlorella reactors. This study provides theoretical and practical support for the safe use of graphene.

scholarly journals Effects of Coal and Sewage Sludge Ashes on Macronutrient Content in Maize (Zea mays L.) Grown on Soil Contaminated with Eco-Diesel Oil

Materials ◽  
2022 ◽  
Vol 15 (2) ◽  
pp. 525
Author(s):  
Mirosław Wyszkowski ◽  
Jadwiga Wyszkowska ◽  
Natalia Kordala ◽  
Agata Borowik
Keyword(s):  
Zea Mays ◽  
Sewage Sludge ◽  
Zea Mays L ◽  
Maize Yield ◽  
Diesel Oil ◽  
Hard Coal ◽  
Slight Reduction ◽  
Nitrogen And Phosphorus ◽  
Soil Enrichment ◽  
Sludge Incineration

Petroleum hydrocarbons, as aggressive components of diesel oils, after migration to the land environment can alter the activity and efficiency of ecosystems. They can also be dangerous to animal and human health. Eco-friendly methods for the reclamation of affected soils is necessary to manage degraded lands. One such method is the use of ashes. The aim of this research was to determine how soil pollution with diesel oil (brand name, Eco-Diesel) affects the chemical composition of maize (Zea mays L.) and whether the application of ash from a combined heat and power plant, as well as from sewage sludge incineration, could reduce the potentially adverse impact of diesel oil on plants. The research results demonstrated that soil contamination with Eco-Diesel oil modified the content of selected macronutrients in the analyzed crop plant. Eco-Diesel oil had a negative effect on maize yield. The highest diesel oil dose in a series without neutralizing substances had a positive effect on the accumulation of most elements, except nitrogen and sodium. Soil enrichment with ash differentiated the content of macronutrients, mainly nitrogen and phosphorus, in the aerial biomass of maize. The ashes increased the yield of maize and content of some macronutrients, mainly nitrogen but also calcium, the latter in a series where soil was treated with ash from sewage sludge thermal recycling. Both types of ash also resulted in a decrease in the plant content of phosphorus, while ash from hard coal caused a slight reduction in the content of potassium in maize. Ash of different origins can be an effective solution in the reclamation of degraded soils, which may then be used for growing energy crops.

scholarly journals Impact of Macronutrients and Micronutrients on Soil Health Nutrients Concentration and Uptake by Maize (Zea mays L)

2021 ◽  
Vol 10 (9) ◽  
pp. 199-206
Author(s):  
M. L. Bubarai U. Bapetel ◽  
A. Musa Mala
Keyword(s):  
Zea Mays ◽  
Zea Mays L ◽  
Soil Health ◽  
Soil Science ◽  
Soil Reaction ◽  
Chemistry Research ◽  
Agricultural Chemistry ◽  
Copper Zinc ◽  
Nutrients Concentration ◽  
The Impact

At the SHUATS Department of Soil Science and Agricultural Chemistry Research Farm, an experiment was conducted with the goal of determining the impact of application of macro and micronutrients, on soil health nutrients concentration and uptake by maize (Zea mays L). The experiment was put up based on this over a two-year period, beginning with the 2017 and 2018 cropping periods. Crbd was used as the experimental technique and it was replicated thrice with the following treatments combinations, NPK @ 50 and 100kgha -1, while for the micronutrients (Boron, Zinc and Copper) three levels of combination were used 0.3, 6 and 9kgha-1. The research project's findings showed all the determinants of soil health like soil reaction organic matter among others are at levels suitable for nutrients actions and plant growth, while plant parameters like maize cob diameter, dry matter, and nutrients concentrations in maize tissues have greatly improved. NPK @100kgha-1, Copper, Zinc, and Boron @ 9kgha-1 were the best treatment combinations with the best results. The above combinations of treatments will be suitable for the soils of that location based on the results of these studies.

scholarly journals Likert scale and change in range of response categories vs. the factors extraction in EFA model

2015 ◽  
Vol 1 (311) ◽  
Author(s):  
Piotr Tarka
Keyword(s):  
Factor Analysis ◽  
Exploratory Factor Analysis ◽  
Rating Scale ◽  
Likert Scale ◽  
Optimal Number ◽  
Number Of Factors ◽  
Scale Experiment ◽  
Methodological Aspects ◽  
The Impact ◽  
Selection Of

Abstract: The objective article is the comparative analysis of Likert rating scale based on the following range of response categories, i.e. 5, 7, 9 and 11 in context of the appropriate process of factors extraction in exploratory factor analysis (EFA). The problem which is being addressed in article relates primarily to the methodological aspects, both in selection of the optimal number of response categories of the measured items (constituting the Likert scale) and identification of possible changes, differences or similarities associated (as a result of the impact of four types of scales) with extraction and determination the appropriate number of factors in EFA model.Keywords: Exploratory factor analysis, Likert scale, experiment research, marketing

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