The use of nutrient bioassays to assess the response of Eucalyptusgrandis to fertilizer application. 2. A field experiment

1993 ◽  
Vol 23 (1) ◽  
pp. 7-13 ◽  
Author(s):  
Helen E. Jones ◽  
John Dighton
Keyword(s):  
Trace Elements ◽  
Nutrient Status ◽  
Fertilizer Application ◽  
Limiting Factor ◽  
Significant Drop ◽  
Fertilizer Experiment ◽  
Root Bioassay ◽  
Negative Effect ◽  
Root Response ◽  
Bioassay Data

The nutrient status of a Eucalyptusgrandis Hill ex Maiden field fertilizer experiment in Natal, South Africa, was assessed at 6 and 18 months by a bioassay test in which the rate of influx of 15N, 32P, and 86Rb in roots excised from trees was measured. Fertilizer treatments consisted of all combinations of two levels of nitrogen (N), phosphorus (P), potassium (K), and trace elements, applied at planting and at either 3 or 6 months. There were also untreated control plots. At 6 months, bioassay influx rates of the three isotopes by the roots were all higher when a nutrient was applied at a lower level than when it was applied at a higher level. Foliar analysis did not indicate that any of the trees were deficient in N, P, or K, although control plants were significantly smaller than fertilized ones. There was no difference in the foliar P or K content between the treatments, although percent N increased with increasing application of N. The greatest difference in the root response between fertilizer levels was in the influx of 15N. Height of the trees was significantly increased by increasing N levels. There was no effect of P or K levels, but there was a negative effect of the combination of high levels of K and trace elements. From the significant drop in root 15N influx following the 6 month fertilizer addition, growth of the trees in response to fertilizer was predicted. At 18 months of age trees receiving their second application of fertilizer at 6 months were as large as those receiving fertilizer at 3 months, confirming growth predictions based on root bioassay data. The bioassay results at 18 months suggested that P may be supplanting N as the major growth limiting factor at this later stage in the development of the stand.

scholarly journals Novel Route Planning Method to Improve the Operational Efficiency of Capacitated Operations. Case: Application of Organic Fertilizer

2021 ◽  
Vol 3 (3) ◽  
pp. 458-477
Author(s):  
Mahdi Vahdanjoo ◽  
Claus G. Sorensen
Keyword(s):  
Organic Fertilizer ◽  
Route Planning ◽  
Fertilizer Application ◽  
Operational Efficiency ◽  
Application Rate ◽  
Simultaneous Optimization ◽  
Limiting Factor ◽  
Application Process ◽  
Optimal Sequence ◽  
Proposed Model

A field area coverage-planning algorithm has been developed for the optimization and simulation of capacitated field operations such as the organic fertilizer application process. The proposed model provides an optimal coverage plan, which includes the optimal sequence of the visited tracks with a designated application rate. The objective of this paper is to present a novel approach for route planning involving two simultaneous optimization criteria, non-working distance minimization and the optimization of application rates, for the capacitated field operations such as organic fertilizer application to improve the overall operational efficiency. The study and the developed algorithm have shown that it is possible to generate the optimized coverage plan based on the required defined capacity of the distributer. In this case, the capacity of the distributer is not considered a limiting factor for the farmers. To validate this new method, a shallow injection application process was considered, and the results of applying the optimization algorithm were compared with the conventional methods. The results show that the proposed method increase operational efficiency by 19.7%. Furthermore, the applicability of the proposed model in robotic application were demonstrated by way of two defined scenarios.

scholarly journals Zinc Biofortification of Cereal Crops: A Review Article

2021 ◽  
pp. 22-28
Author(s):  
Nooruldeen S. Ali
Keyword(s):  
Food Additives ◽  
Food Product ◽  
Nutrient Status ◽  
Food Products ◽  
Zn Deficiency ◽  
Limiting Factor ◽  
Poor People ◽  
Sustainable Solutions ◽  
Nutritional Health ◽  
Soil Zn

Micronutrient deficiency can be considered as one of the yield "quantity and quality" limiting factor in arid calcareous lands and can be considered as the troubling component of hunger. Therefore, enriching food products through adding nutrients to a food product or through increasing soil fertility and breeding crop for nutrient efficiency are alternatives available to improve food quality. However, poor people have no excess to food additives and can benefit from naturally enriched food products or what being called Biofortification. The existence of a general geographical overlap between soil Zn deficiency and human Zn deficiency has been already postulated. As agriculture-based food products are the major source of human nutrition, the relationship between the nutrient status of soils, food crops, and human health is understandable. poor but also deliver all the essential nutrients needed for adequate nutritional health. Sustainable solutions to malnutrition will only be found by closely linking agriculture to nutrition and health. The undergoing review would discuss these concepts and their implementation and uses with special concern on Iraqi conditions.

scholarly journals The effect of osmocote fertilizers on growth and nutrient status of Carex buchananii Berggr.

2015 ◽  
Vol 68 (1) ◽  
pp. 75-80
Author(s):  
Monika Henschke ◽  
Ewelina Wojciechowska ◽  
Agnieszka Błaszyk ◽  
Katarzyna Araszkiewicz
Keyword(s):  
Nutrient Status ◽  
Fertilizer Application ◽  
Growing Up ◽  
Fresh Weight ◽  
Application Rates

An experiment on the effect of Osmocote fertilizers on growth and nutrient status of <em>Carex buchananii</em> was conducted in the years 2008–2009. <em>Carex buchananii</em> is a dense-tufted sedge growing up to 60 cm in height, with very narrow, stiff, red, copper and olive colored leaves throughout the season. Plants were grown in a greenhouse in pots with peat substrate for 18 weeks. The differentiating factors included the type of fertilizer, i.e. Exact Standard 16:11:11 and Osmocote Exact High Start 11:11:19, and fertilizer application rates of 2 and 4 g dm<sup>−3</sup>, the phase of growth, i.e. 1 to 9 weeks and 9 to 18 weeks of culture. The greatest increment in the tuft circumference of <em>C. buchananii</em> was recorded in the first 9 weeks of culture, while that of the fresh weight of aboveground parts – in the period from 9 to 18 weeks. The application of Osmocote Exact High Start at 4 g dm<sup>−3</sup> in the culture of <em>C. buchananii</em> resulted in the production of the desired quality of the plants with a greater tuft circumference and shorter leaves. It was shown that best quality plants contained in their aboveground parts the following amounts of macronutrients and sodium (g kg<sup>−1</sup>): N – 18.9, P – 3.5, K – 37.2, Ca – 5.8, Mg – 3.0, and Na – 0.3.

scholarly journals Comparative Analysis of Cutting Forces, Torques, and Vibration in Drilling of Bovine, Porcine, and Artificial Femur Bone with Considerations for Robot Effector Stiffness

2020 ◽  
Vol 2020 ◽  
pp. 1-12
Author(s):  
Oluseyi Adewale Orelaja ◽  
Xingsong Wang ◽  
Donghua Shen ◽  
Dauda Sh. Ibrahim ◽  
Tianzheng Zhao ◽  
...  
Keyword(s):  
Comparative Analysis ◽  
Cutting Forces ◽  
Spindle Speed ◽  
Depth Of Cut ◽  
Drilling Process ◽  
Robot Arm ◽  
Drilling Force ◽  
Significant Drop ◽  
Negative Effect ◽  
Conventional Drilling

Bone drilling is known as one of the most sensitive milling processes in biomedical engineering field. Fracture behavior of this cortical bone during drilling has attracted the attention of many researchers; however, there are still impending concerns such as necrosis, tool breakage, and microcracks due to high cutting forces, torques, and high vibration while drilling. This paper presents a comparative analysis of the cutting forces, torques, and vibration resulted on different bone samples (bovine, porcine, and artificial femur) using a 6dof Robot arm effector with considerations of its stiffness effects. Experiments were conducted on two spindle speeds of 1000 and 1500 rpm with a drill bit diameter of 2.5 mm and 6 mm depth of cut. The results obtained from the specimens were processed and analyzed using MATLAB R2015b and Visio 2000 software; these results were then compared with a prior test using manual and conventional drilling methods. The results obtained show that there is a significant drop in the average values of maximum drilling force for all the bone specimens when the spindle speed changes from 1000 rev/min to 1500 rev/min, with a drop from (20.07 to 12.34 N), approximately 23.85% for bovine, (11.25 to 8.14 N) with 16.03% for porcine, and (5.62 to 3.86 N) with 33.99% for artificial femur. The maximum average values of torque also decrease from 41.2 to 24.2 N·mm (bovine), 37.0 to 21.6 N·mm (porcine), and 13.6 to 6.7 N·mm (artificial femur), respectively. At an increase in the spindle speed, the vibration amplitude on all the bone samples also increases considerably. The variation in drilling force, torque, and vibration in our result also confirm that the stiffness of the robot effector joint has negative effect on the bone precision during drilling process.

scholarly journals  Soil environment and nutrient status of Norway spruce (Picea abies [L.] Karst.) underplantings in conditions of the 8th FAZ in the Hrubý Jeseník Mts.

2011 ◽  
Vol 57 (No. 4) ◽  
pp. 141-152
Author(s):  
J. Pecháček ◽  
D. Vavříček ◽  
P. Samec
Keyword(s):  
Picea Abies ◽  
Norway Spruce ◽  
Nutrient Deficiency ◽  
Normal Growth ◽  
Nutrient Status ◽  
Limiting Factor ◽  
Soil Environment ◽  
Deficiency Symptoms ◽  
Humus Substances ◽  
Statistical Survey

The main objective of this study was to investigate the causes of nutrient deficiency symptoms in Norway spruce (Picea abies [L.] Karst.) underplantings in the Hrub&yacute; Jesen&iacute;k Mts. In the area concerned 19 research plots were established, representing the ridge sites of the 8th FAZ of acid edaphic categories. On these plots samples were taken from topmost soil horizons and needle samples were collected in two series &ndash; from healthy and from damaged trees. The results of this study demonstrate that the nutrient deficiency symptoms and reduced vitality of evaluated underplantings were caused by the insufficient uptake of main nutrients (Mg, P, K, N<sub>t</sub>). High contents of toxic elements Al, S in damaged needles are another factor that negatively influences the health status of these underplantings.<br />A statistical survey showed that damage to underplantings increased with decreasing proportions of main nutrients (N<sub>t</sub>, Mg, Ca, K) in organomineral horizons. At the same time the content of basic nutrients (N<sub>t</sub>, Mg, Ca, K) was found to increase in this horizon with an increasing proportion of oxidizable organic carbon (C<sub>ox</sub>). The proportion of humus substances and the content of basic nutrients (N<sub>t</sub>, Mg, Ca, K) in organomineral horizons become a limiting factor for the normal growth and development of Norway spruce plantings in the ridge part of the Hrub&yacute; Jesen&iacute;k Mts.

scholarly journals The Effects of Biofertilizers on Growth, Soil Fertility, and Nutrients Uptake of Oil Palm (Elaeis Guineensis) under Greenhouse Conditions

Processes ◽  
2020 ◽  
Vol 8 (12) ◽  
pp. 1681
Author(s):  
Aaronn Avit Ajeng ◽  
Rosazlin Abdullah ◽  
Marlinda Abdul Malek ◽  
Kit Wayne Chew ◽  
Yeek-Chia Ho ◽  
...  
Keyword(s):  
Soil Fertility ◽  
Nutrient Uptake ◽  
Oil Palm ◽  
Elaeis Guineensis ◽  
Combined Treatment ◽  
Soil Nutrient ◽  
Nutrient Status ◽  
Fertilizer Application ◽  
Chemical Fertilizer ◽  
Greenhouse Study

The full dependency on chemical fertilizers in oil palm plantation poses an enormous threat to the ecosystem through the degradation of soil and water quality through leaching to the groundwater and contaminating the river. A greenhouse study was conducted to test the effect of combinations of biofertilizers with chemical fertilizer focusing on the soil fertility, nutrient uptake, and the growth performance of oil palms seedlings. Soils used were histosol, spodosol, oxisol, and ultisol. The three treatments were T1: 100% chemical fertilizer (NPK 12:12:17), T2: 70% chemical fertilizer + 30% biofertilizer A (CF + BFA), and T3: 70% + 30% biofertilizer B (CF + BFB). T2 and T3, respectively increased the growth of oil palm seedlings and soil nutrient status but seedlings in oxisol and ultisol under T3 had the highest in almost all parameters due to the abundance of more efficient PGPR. The height of seedlings in ultisol under T3 was 22% and 17% more than T2 and T1 respectively, with enhanced girth size, chlorophyll content, with improved nutrient uptake by the seedlings. Histosol across all treatments has a high macronutrient content suggesting that the rate of chemical fertilizer application should be revised when planting using the particular soil. With the reduction of chemical fertilizer by 25%, the combined treatment with biofertilizers could enhance the growth of the oil palm seedlings and soil nutrient properties regardless of the soil orders.

Sulphur and nitrogen nutrition and their interactive effects on Dothistroma infection in Pinusradiata

1986 ◽  
Vol 16 (5) ◽  
pp. 1055-1062 ◽  
Author(s):  
Marcia J. Lambert
Keyword(s):  
Nitrogen Fertilizer ◽  
Nitrogen Nutrition ◽  
Fertilizer Application ◽  
Positive Influence ◽  
Interactive Effects ◽  
Strong Positive Correlation ◽  
Infection Level ◽  
Foliar Nutrition ◽  
Volume Increment ◽  
Negative Effect

Nitrogen and sulphur fertilizers were applied to a 4-year-old Pinusradiata plantation in northern New South Wales and the results were monitored for 7 years. The aim was to study the effects of sulphur and nitrogen nutrition on tree growth and their interactions on Dothistroma infection. Sulphur (300 kg S ha−1), applied as gypsum, elevated foliage sulphate sulphur levels for up to 7 years after treatment, but no direct effects on growth were noted. The low nitrogen fertilizer level (100 kg N ha−1) had a positive influence on volume increment, while the high nitrogen fertilizer application (400 kg N ha−1) significantly depressed volume increment. This latter negative effect was attributed to induced sulphur and phosphorus deficiencies. Sulphur deficiency resulted in highly increased arginine concentrations in current foliage and there was a strong positive correlation between arginine concentration and tree infection level of Dothistroma needle cast fungus, the highest levels of infection being in the nitrogen-treated plots. Relationships between foliar nutrition and foliar fungal infection are discussed.

Lake Acidification as a Limiting Factor in the Distribution of the Freshwater Amphipod Hyalella azteca

1986 ◽  
Vol 43 (2) ◽  
pp. 288-292 ◽  
Author(s):  
M. Stephenson ◽  
G. L. Mackie
Keyword(s):  
Surface Water ◽  
Hyalella Azteca ◽  
Lake Acidification ◽  
Limiting Factor ◽  
Short Term ◽  
Natural Surface ◽  
Bioassay Data ◽  
Plastic Lake

The distribution of the freshwater amphipod Hyalella azteca in 79 Ontario lakes suggests that its absence may be a good indicator of lake acidification. Hyalella azteca was present in 69 of 71 nonacidified lakes, and absent in 8 of 8 lakes which either are now ar recently were considered acidified. Bioassay data indicate a 96-h LC50 of pH 4.4 and a 10-d threshold LC50 of pH 4.5 for H. azteca in a natural surface water. Hyalella azteca is extremely rare in Plastic Lake, which undergoes severe short-term acidification in spring, and recruitment is delayed 2 wk in Heeney Lake which undergoes similar short-term acidification, in Dickie, Harp, Red Chalk, and Blue Chalk lakes, where springtime pH depressions below pH 4.7 were not recorded, H. azteca is abundant.

scholarly journals Impact of the COVID-19 Epidemic on Stroke Care and Potential Solutions

Stroke ◽  
2020 ◽  
Vol 51 (7) ◽  
pp. 1996-2001 ◽  
Author(s):  
Jing Zhao ◽  
Hang Li ◽  
David Kung ◽  
Marc Fisher ◽  
Ying Shen ◽  
...  
Keyword(s):  
Big Data ◽  
Hospital Admissions ◽  
Stroke Care ◽  
Limiting Factors ◽  
Limiting Factor ◽  
Significant Drop ◽  
The Public ◽  
Key Factor ◽  
Prehospital Delays ◽  
The Impact

Background and Purpose: When the coronavirus disease 2019 (COVID-19) outbreak became paramount, medical care for other devastating diseases was negatively impacted. In this study, we investigated the impact of the COVID-19 outbreak on stroke care across China. Methods: Data from the Big Data Observatory Platform for Stroke of China consisting of 280 hospitals across China demonstrated a significant drop in the number of cases of thrombolysis and thrombectomy. We designed a survey to investigate the major changes during the COVID-19 outbreak and potential causes of these changes. The survey was distributed to the leaders of stroke centers in these 280 hospitals. Results: From the data of Big Data Observatory Platform for Stroke of China, the total number of thrombolysis and thrombectomy cases dropped 26.7% ( P <0.0001) and 25.3% ( P <0.0001), respectively, in February 2020 as compared with February 2019. We retrieved 227 valid complete datasets from the 280 stroke centers. Nearly 50% of these hospitals were designated hospitals for COVID-19. The capacity for stroke care was reduced in the majority of the hospitals. Most of the stroke centers stopped or reduced their efforts in stroke education for the public. Hospital admissions related to stroke dropped ≈40%; thrombolysis and thrombectomy cases dropped ≈25%, which is similar to the results from the Big Data Observatory Platform for Stroke of China as compared with the same period in 2019. Many factors contributed to the reduced admissions and prehospital delays; lack of stroke knowledge and proper transportation were significant limiting factors. Patients not coming to the hospital for fear of virus infection was also a likely key factor. Conclusions: The COVID-19 outbreak impacted stroke care significantly in China, including prehospital and in-hospital care, resulting in a significant drop in admissions, thrombolysis, and thrombectomy. Although many factors contributed, patients not coming to the hospital was probably the major limiting factor. Recommendations based on the data are provided.

GROWTH AND BIOCHEMICAL RESPONSES ON CORN PLANTS CULTIVATED IN SOILS CONTAMINATED WITH CADMIUM AND ZINC

2017 ◽  
Vol 16 (2) ◽  
pp. 193
Author(s):  
LORENA GABRIELA ALMEIDA ◽  
ADELCIO DE PAULA JORGE ◽  
EDER MARCOS DA SILVA ◽  
PAULO CÉSAR MAGALHÃES ◽  
HUGO RAFAEL BENTZEN SANTOS ◽  
...  
Keyword(s):  
Trace Elements ◽  
Agricultural Production ◽  
Synergistic Effects ◽  
Limiting Factor ◽  
Corn Plant ◽  
Physiological Mechanisms ◽  
Specific Behavior ◽  
Biochemical Responses ◽  
High Concentrations ◽  
Corn Plants

Contamination with trace elements is characterized by an abiotic stress that represents a limiting factor in agricultural production. As cadmium (Cd) and Zinc (Zn) are physically and chemically similar, they can interact with the environment, causing antagonistic or synergistic effects. In this sense, physiological mechanisms to exclude detoxify or compartmentalize the excess of those trace elements is crucial for the survival of the vegetables when they are exposed to high concentrations of those elements. To comprehend the responses of the species sensible to the presence of Cd and Zn, this study aims to access the behavior of corn plants (Zea mays) cultivated in Cambisoils and Latosol with growing concentrations of Cd/Zn in a 21 days period. We performed growth and biochemical analyzes like antioxidant enzyme SOD, CAT and APX activity, hydrogen peroxide and lipidic peroxidation. Our data showed the specific behavior of cultivated corn plant in each of the soils analyzed. We observed that the interaction between both the elements resulted in a synergistic effect, negatively influencing all the analyzed parameters.  

Sign in / Sign up

Export Citation Format

Share Document