scholarly journals Thermal Simulation of a Screenhouse Proposed for Fruit and Vegetable Production in the Lowlands of Panama

2021 ◽  
Vol 39 (4) ◽  
pp. 1097-1106
Author(s):  
Edwin Villagrán
Keyword(s):  
Production Systems ◽  
Abiotic Factors ◽  
Crop Productivity ◽  
Climatic Conditions ◽  
Economic Losses ◽  
Vegetable Production ◽  
Socioeconomic Conditions ◽  
Warm Climate ◽  
Computational Fluid Dynamics Simulations ◽  
Dynamics Simulations

In developing countries, open field agricultural production is highly vulnerable to biotic and abiotic factors limiting crop productivity, generating economic losses and affecting food security. Therefore, one of the strategies that can improve these production systems is the implementation of the crops under cover technically adapted to the climatic and socioeconomic conditions of each region. The objective of this research was to analyze the thermal behavior and airflow patterns of an insect-proof screenhouse through computational fluid dynamics simulations using a 3D model. The results obtained for the multiannual monthly climatic conditions of a warm climate region in Panama showed that the airflow velocities inside the structure were lower between 76.8 and 80.2% with respect to the external velocity. The most critical scenarios showed temperature differences below 2℃ inside the screenhouse with respect to the outside. This value can be considered low as compared to the behavior of naturally ventilated greenhouses.

scholarly journals Insect Pest Complex of Wheat Crop

2021 ◽  
Author(s):  
Mirza Abdul Qayyum ◽  
Shafqat Saeed ◽  
Unsar Naeem-Ullah ◽  
Amar Matloob ◽  
Muhammad Wajid ◽  
...  
Keyword(s):  
Proper Time ◽  
Abiotic Factors ◽  
Insect Pest ◽  
Management Strategies ◽  
Triticum Aestivum L ◽  
Climatic Conditions ◽  
Economic Losses ◽  
Taxonomic Rank ◽  
Reproductive Part ◽  
The Rich

Wheat Triticum aestivum L. is grown on broad range of climatic conditions because of edible grains, cereal crop and stable food of about 2 Billion peoples worldwide. Additionally, it is the rich source of carbohydrates (55–60%), vegetable proteins and contributed 50–60% daily dietary requirement in Pakistan. Globally, wheat crops is grown over 90% area of total cultivated area; facing devastating biotic and abiotic factors. The estimated economic losses in wheat quantity and quality are about 4 thousands per tonne per year including physical crop losses and handling. Economic losses of about 80–90 million USD in Pakistan are recorded due to inadequate production and handling losses. Wheat agro-ecosystem of the world colonizes many herbivore insects which are abundant and causing significant losses. The feeding style of the insects made them dispersive from one habitat to another imposing significant crop loss. Areas of maximum wheat production are encountered with either insect which chew the vegetative as well as reproductive part or stem and root feeders. This chapter provides the pest’s taxonomic rank, distribution across the globe, biology and damage of chewing and sucking insect pest of wheat. It is very important to study biology of the pest in accordance with crop cycle to forecast which insect stage is economically important, what the proper time to manage pest is and what type of control is necessary to manage crop pest. The chapter will provide management strategies well suited to pest stage and environment.

scholarly journals AGRO-ECONOMIC INDICATORS FOR CARROT UNDER GREEN MANURE IN A SEMI-ARID ENVIRONMENT

2021 ◽  
Vol 34 (2) ◽  
pp. 257-265
Author(s):  
JOSIMAR NOGUEORA DA SILVA ◽  
FRANCISCO BEZERRA NETO ◽  
JAILMA SUERDA SILVA DE LIMA ◽  
ARIDÊNIA PEIXOTO CHAVES ◽  
ELIZÂNGELA CABRAL DOS SANTOS ◽  
...  
Keyword(s):  
Production Systems ◽  
Arid Environment ◽  
Crop Productivity ◽  
Biological Properties ◽  
Economic Indicators ◽  
Control Treatment ◽  
Calotropis Procera ◽  
Vegetable Production ◽  
Net Income ◽  
Growing Seasons

ABSTRACT Green manuring is an important management strategy in tuberous vegetable production systems, since it improves the physical, chemical and biological properties of the soil and, consequently, increases in crop productivity and ecosystem balance. The objective of this work was to evaluate the agro-economic efficiency of carrot cultivation as a function of Calotropis procera biomass amounts incorporated into the soil during two growing seasons in a semiarid environment. The experiments were conducted in an experimental design of randomized complete blocks, with four treatments and five replications. The treatments consisted of four C. procera biomass amounts (20, 35, 50 and 65 t ha-1) incorporated into the soil. In each experiment, one plot with carrot without fertilization (control) was planted, for the purpose of comparison. The characteristics evaluated in the carrot were productivities of total and commercial roots, classified productivity of roots and production economic indicators. The maximum productivity of carrot roots of 35.90 t ha-1 was possible with the incorporation of 47.60 t ha-1 of C. procera biomass into the soil. The maximum net income of R$ 33.744,07 ha-1 in the cultivation of this vegetable it was achieved with the addition of the C. procera biomass amount to the soil of 42.81 t ha-1. The return rates obtained for the carrot cultivation in these optimized quantities were 1.53 and 1.28, respectively, of those achieved in the control treatment (without fertilization).

scholarly journals History of Controlled Environment Horticulture: Greenhouses

HortScience ◽  
2022 ◽  
Vol 57 (2) ◽  
pp. 239-246
Author(s):  
Krishna Nemali
Keyword(s):  
High Efficiency ◽  
Production Systems ◽  
Low Cost ◽  
Farming Systems ◽  
Weather Conditions ◽  
Crop Productivity ◽  
Climatic Conditions ◽  
African Countries ◽  
Rigid Plastic ◽  
Intensive Farming

Modern greenhouses are intensive farming systems designed to achieve high efficiency and productivity. Plants are produced year-round in greenhouses by maintaining the environment at or near optimum levels regardless of extreme weather conditions. Many scientific discoveries and technological advancements that happened in the past two centuries paved the way for current state-of-the-art greenhouses. These include, but are not limited to, advancements in climate-specific structural designs and glazing materials, and temperature control, artificial lighting, and hydroponic production systems. Greenhouse structures can be broadly grouped into four distinct designs, including tall Venlo greenhouses of the Netherlands, passive solar greenhouses of China, low-cost Parral greenhouses of the Mediterranean region, and gutter-connected polyethylene houses of India and African countries. These designs were developed to suit local climatic conditions and maximize the return on investment. Although glass and rigid plastic options are available for glazing, the development of low-cost and lightweight plastic glazing materials (e.g., polyethylene) enabled widespread growth of the greenhouse industry in the developing world. For temperate regions, supplemental lighting technology is crucial for year-round production. This heavily relies on advancements in electro-lighting during the 19th and 20th centuries. The development of hydroponic production systems for the controlled delivery of nutrients further enhanced crop productivity. This article addresses important historical events, scientific discoveries, and technological improvements related to advancements in these areas.

scholarly journals Two-Dimensional Numerical Study of the Microclimate Generated in Three Screenhouses for the Climatic Conditions of the Colombian Caribbean

2021 ◽  
Vol 39 (2) ◽  
pp. 460-468
Author(s):  
Edwin Villagran
Keyword(s):  
Wind Speed ◽  
Numerical Model ◽  
Production Systems ◽  
Numerical Study ◽  
Climatic Conditions ◽  
Two Dimensional ◽  
Warm Climate ◽  
Wind Speeds ◽  
Average Temperature ◽  
Roof Area

Insect proof screenhouse is increasingly used in tropical countries with a warm climate, as this type of structure is more economical than greenhouses and gives farmers the opportunity to optimize their production systems. In this work we used an experimentally validated two-dimensional numerical model, the objective was to study the air flow patterns and the thermal and hygrometric behavior of three screenhouses differentiated in their geometric configuration of the roof area and under four (4) outside wind speeds. The results obtained allowed us to find that the airflow speed inside the screenhouse can be maximized with respect to the most critical scenario by 29% for a wind speed of 0.5 ms-1 and up to 292% for a wind speed of 3.0 ms-1, which generates reductions in the average temperature inside the structure of -0.2℃ (0.5 ms-1) and up to -2.2℃ (3 ms-1). While the relative humidity presented values of 1.6% and 6.3% higher for these same speeds.

Russia in the World Production and Market of Potatoes and Fruit and Vegetable Products

2020 ◽  
pp. 74-83
Author(s):  
Yu.I. Agirbov ◽  
◽  
R.R. Mukhametzyanov ◽  
E.V. Britik ◽  
◽  
...  
Keyword(s):  
Fruits And Vegetables ◽  
World Market ◽  
Climatic Conditions ◽  
Global Rating ◽  
Vegetable Production ◽  
World Production ◽  
Fruit And Vegetable ◽  
Vegetable Products ◽  
The World ◽  
Qualitative Changes

In 1961-2018 in the world as a whole, the gross harvest of potatoes increased from 290.6 million tons to 368.2 million tons, that is, 1.36 times. Over the same period, the production of vegetables and food melons increased from 197.7 million tons to 1,088.8 million tons (5.51 times), and fruits and berries from 199.9 million tons to 867.8 million tons (4.34 times). In a number of states in 1992-2018 the corresponding increase significantly exceeded the average values for the world as a whole, as a result of which their place in the global ranking increased, and the positions of some traditional producers of potatoes and fruits and vegetables decreased. For example, in terms of gross harvest of potatoes in 1992, Russia was in first place, and Poland was in third, while in 2018 they were in 4th and 9th positions, respectively. In terms of vegetable production, Italy and Japan were displaced from 4th and 5th places, which were taken by Turkey and Nigeria. In terms of gross harvests of fruits and berries, Turkey occupied the fifth position in total world production by 2018, although in 1992 it belonged to Italy. Quantitative and qualitative changes inevitably have a significant impact on both the volume of the world market and the parameters of international trade in potatoes, vegetables and melons, fruits and berries. Processes in foreign economic liberalization and economic integration contributed to an increase in the specialization and concentration of production of relevant plants in countries with more favorable natural and climatic conditions, as well as a gradual increase in demand for potatoes, vegetables and melons, fruits and berries from a number of states, including those that used to meet the needs of their population in large volumes at the expense of their own producers. The Russian Federation is one of the significant players in the world potato and fruit and vegetable market. Despite the increase in gross fruit and vegetable production in recent years, Russia’s positions in the global rating dropped from 7th to 10th place in vegetables and melons, from 20th to 31st place in fruits and berries. As for potatoes, there was a decrease in the volume of its production, as a result, Russia dropped from 1st place in 1992 to 4th place in 2018.

scholarly journals Integrated economic and environmental building classification and optimal seismic vulnerability/energy efficiency retrofitting

2021 ◽  
Author(s):  
Martina Caruso ◽  
Rui Pinho ◽  
Federica Bianchi ◽  
Francesco Cavalieri ◽  
Maria Teresa Lemmo
Keyword(s):  
Energy Efficiency ◽  
Life Cycle ◽  
Seismic Hazard ◽  
Environmental Impacts ◽  
Classification System ◽  
Seismic Vulnerability ◽  
Performance Metrics ◽  
Climatic Conditions ◽  
Economic Losses ◽  
Operational Energy

AbstractA life cycle framework for a new integrated classification system for buildings and the identification of renovation strategies that lead to an optimal balance between reduction of seismic vulnerability and increase of energy efficiency, considering both economic losses and environmental impacts, is discussed through a parametric application to an exemplificative case-study building. Such framework accounts for the economic and environmental contributions of initial construction, operational energy consumption, earthquake-induced damage repair activities, retrofitting interventions, and demolition. One-off and annual monetary expenses and environmental impacts through the building life cycle are suggested as meaningful performance metrics to develop an integrated classification system for buildings and to identify the optimal renovation strategy leading to a combined reduction of economic and environmental impacts, depending on the climatic conditions and the seismic hazard at the site of interest. The illustrative application of the framework to an existing school building is then carried out, investigating alternative retrofitting solutions, including either sole structural retrofitting options or sole energy refurbishments, as well as integrated strategies that target both objectives, with a view to demonstrate its practicality and to explore its ensuing results. The influence of seismic hazard and climatic conditions is quantitatively investigated, by assuming the building to be located into different geographic locations.

scholarly journals Pretreatment with probiotics ameliorate gut health and necrotic enteritis in broiler chickens, a substitute to antibiotics

AMB Express ◽  
2020 ◽  
Vol 10 (1) ◽  
Author(s):  
Danish Sharafat Rajput ◽  
Dong Zeng ◽  
Abdul Khalique ◽  
Samia Sharafat Rajput ◽  
Hesong Wang ◽  
...  
Keyword(s):  
Broiler Chickens ◽  
Production Systems ◽  
Economic Losses ◽  
Necrotic Enteritis ◽  
Poultry Production ◽  
Gut Health ◽  
Growth Promoters ◽  
Broiler Performance ◽  
Antibiotic Growth Promoters ◽  
Microbial Strains

AbstractNecrotic enteritis (NE) is being considered as one of the most important intestinal diseases in the recent poultry production systems, which causes huge economic losses globally. NE is caused by Clostridium perfringens, a pathogenic bacterium, and normal resident of the intestinal microflora of healthy broiler chickens. Gastrointestinal tract (GIT) of broiler chicken is considered as the most integral part of pathogen’s entrance, their production and disease prevention. Interaction between C. perfringens and other pathogens such as Escherichia coli and Salmonella present in the small intestine may contribute to the development of NE in broiler chickens. The antibiotic therapy was used to treat the NE; however European Union has imposed a strict ban due to the negative implications of drug resistance. Moreover, antibiotic growth promoters cause adverse effects on human health as results of withdrawal of antibiotic residues in the chicken meat. After restriction on use of antibiotics, numerous studies have been carried out to investigate the alternatives to antibiotics for controlling NE. Thus, possible alternatives to prevent NE are bio-therapeutic agents (Probiotics), prebiotics, organic acids and essential oils which help in nutrients digestion, immunity enhancement and overall broiler performance. Recently, probiotics are extensively used alternatives to antibiotics for improving host health status and making them efficient in production. The aim of review is to describe a replacement to antibiotics by using different microbial strains as probiotics such as bacteria and yeasts etc. having bacteriostatic properties which inhibit growth of pathogens and neutralize the toxins by different modes of action.

scholarly journals Revisiting Sulphur—The Once Neglected Nutrient: It’s Roles in Plant Growth, Metabolism, Stress Tolerance and Crop Production

Agriculture ◽  
2021 ◽  
Vol 11 (7) ◽  
pp. 626
Author(s):  
Tinashe Zenda ◽  
Songtao Liu ◽  
Anyi Dong ◽  
Huijun Duan
Keyword(s):  
Plant Growth ◽  
Abiotic Stresses ◽  
Crop Production ◽  
Production Systems ◽  
Crop Productivity ◽  
Plant Phenotyping ◽  
Special Importance ◽  
Nutrient Deficiencies ◽  
Sulphur Nutrition ◽  
Physiological Processes

Sulphur plays crucial roles in plant growth and development, with its functions ranging from being a structural constituent of macro-biomolecules to modulating several physiological processes and tolerance to abiotic stresses. In spite of these numerous sulphur roles being well acknowledged, agriculture has paid scant regard for sulphur nutrition, until only recently. Serious problems related to soil sulphur deficiencies have emerged and the intensification of food, fiber, and animal production is escalating to feed the ever-increasing human population. In the wake of huge demand for high quality cereal and vegetable diets, sulphur can play a key role in augmenting the production, productivity, and quality of crops. Additionally, in light of the emerging problems of soil fertility exhaustion and climate change-exacerbated environmental stresses, sulphur assumes special importance in crop production, particularly under intensively cropped areas. Here, citing several relevant examples, we highlight, in addition to its plant biological and metabolism functions, how sulphur can significantly enhance crop productivity and quality, as well as acclimation to abiotic stresses. By this appraisal, we also aim to stimulate readers interests in crop sulphur research by providing priorities for future pursuance, including bettering our understanding of the molecular processes and dynamics of sulphur availability and utilization in plants, dissecting the role of soil rhizospherical microbes in plant sulphur transformations, enhancing plant phenotyping and diagnosis for nutrient deficiencies, and matching site-specific crop sulphur demands with fertilizer amendments in order to reduce nutrient use inefficiencies in both crop and livestock production systems. This will facilitate the proper utilization of sulphur in crop production and eventually enhance sustainable and environmentally friend food production.

Sign in / Sign up

Export Citation Format

Share Document