Cercas vivas en sistemas de producción tropicales:  una revisión mundial de los usos y percepciones

Live fences in tropical production systems: a global review of uses and perceptions. The expansion of agricultural and livestock production has been a key factor in deforestation in the world and especially in the tropical region. Currently, more than half of the Earth’s surface is used for the establishment of production systems; in this context, live fences can generate positive effects on the environment and provide environmental goods and services. In this work, we reviewed the effects of live fences on production systems from the tropical regions of America, Africa, Asia and Australia, analyzing the uses and perceptions of farmers that have made use of these fences. It was found that live fences were mainly related to the delimitation of farms and pastures. However, their uses and benefits are manifold, among which we found: provide forage, wood extraction, fruit supply, windbreaks, medicinal, to avoid soil erosion, moisture retention and nutritional support. In addition, other positive perceptions were: increasing landscape connectivity, increasing economic incomes, reducing production costs, reducing pressure on remaining vegetation, keeping maintenance costs down, contributing to pest control, and improving fertility. However, negative perceptions included the excessive work in repairing or pruning them, shade negative impact on agricultural production, lack of information discourages establishment, high establishment costs, generation of property conflicts and management difficulty. It was found that the uses by farmers are focused on improving the yields of productive systems, but also on the conservation of natural resources especially soil and biodiversity. We proposed research topics for the future, as determining the criteria in the selection of native species to establish and enrich living fences valuing ecological and socioeconomic aspects; in additionally, we must deepen the benefits they produce on the yields of productive systems. We suggest the development of live fences studies in the tropical region of Australasia, because no data was found for this region, in order to know the biodiversity and services status that they provide to the rural communities. As a conclusion, it will be important to generate initiatives that encourage the formulation of rural policies, the creation of programs that encourage the establishment of live fences, whether through payments for environmental services, tax compensation or other mechanisms. Providing adequate information to farmers and livestock farmers is a key aspect on dynamizing the establishment of live fences. Rev. Biol. Trop. 66(2): 739-753. Epub 2018 June 01.

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Simulating the effect of climate on star grass growth and quality and its capacity to support milk production in the tropical regions of Mexico

Ciência Rural ◽

10.1590/0103-8478cr20130987 ◽

2014 ◽

Vol 44 (8) ◽

pp. 1486-1493 ◽

Cited By ~ 1

Author(s):

Gilberto Yong Angel ◽

Vicente Celestino Pires Silveira ◽

Francisca Avilés Nova ◽

Octavio Alonso Castelán Ortega

Keyword(s):

Milk Production ◽

Milk Yield ◽

Production Systems ◽

Growth And Yield ◽

Small Scale ◽

Data Set ◽

Tropical Regions ◽

Concentrate Supplementation ◽

Positive Effects ◽

Grass Growth

The objective of the present study was to simulate the effect of the seasonal variation of climate on the nutritional value and dry matter yield of star grass and its capacity to support milk production alone or with concentrate supplementation in small-scale milk production systems in the tropical regions of Mexico. Two mathematical simulation models were used, the first model simulates the growth and yield of star grass (Cynodon plectostachyus), and the second model simulates the productive performance of dairy cows. Both models were integrated in a decision-making support system (DSSTROP). Model's predictions were validated by a calibration exercise for each data set from three experiments on the effect of concentrate supplementation on milk yield. The DSSTROP predictions and the results from the experiments were compared by regression analysis. The results suggest that the DSSTROP adequately predicts milk production (R2=0.74). The DSSTROP predictions suggest that milk production based solely on star grass may occur only between June to August. The highest milk yield (8.5kg cow-1 day-1) sustained solely on grass was achieved in June, followed by lower yields of <5kg cow-1 day-1 in July and August. Milk production without concentrates can be explained by the positive effects of the rain observed during June to August on grass growth, and to the fact that grass quality is best at the beginning of the rainy season. It is concluded that June to August is the best time of the year for milk production base solely on grass. It also was concluded that the use of large quantities of concentrates by farmers may be justified because milk production with star grass alone may not be possible especially during the dry season.

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Profitability of Artichoke Growing in the Mediterranean Area

HortScience ◽

10.21273/hortsci.50.9.1349 ◽

2015 ◽

Vol 50 (9) ◽

pp. 1349-1352 ◽

Cited By ~ 5

Author(s):

Filippo Sgroi ◽

Mario Foderà ◽

Anna Maria Di Trapani ◽

Salvatore Tudisca ◽

Riccardo Testa

Keyword(s):

Production Systems ◽

Specific Activity ◽

Negative Impact ◽

Economic Recession ◽

Mediterranean Area ◽

Production Costs ◽

African Countries ◽

Market Prices ◽

The Mediterranean ◽

Eventual Collapse

Cultivation of artichokes for production is significant in the Mediterranean Basin. Italy represents an important productive hub and in this context, Sicily has been one of the foremost production areas. Artichoke production is a stable element of either specialized or mixed production systems in the region. However, due to the economic recession and increasing imports of artichokes from North African countries, many companies are undergoing crisis, with concerns for the negative impact on the socioeconomic fabric, in terms of the rising unemployment an eventual collapse of this specific activity would determine. According to the theory of economic development, a prerequisite of a territory’s development is that its economic enterprises be competitive. Ensuing from this hypothesis, this article analyzes the profitability of artichoke production in the Mediterranean. The study was conducted in Sicily, an island in the heart of the Mediterranean, where its cultivation is a long-standing tradition. Our results showed a low profitability for artichoke cultivation in relation to the unfavorably high production costs, whereas the low market prices also reflect the competition from countries of North Africa.

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Performance of potato clones for processing in subtropical and high-altitude tropical regions of Brazil

Colloquium Agrariae ◽

10.5747/ca.2021.v17.n1.a421 ◽

2021 ◽

Vol 17 (1) ◽

pp. 66-78

Author(s):

Giovani Olegario da Silva ◽

Agnaldo Donizete Ferreira de Carvalho ◽

Gabriel Emiliano Pereira ◽

Carlos Francisco Ragassi ◽

Antônio César Bortoletto ◽

...

Keyword(s):

High Altitude ◽

Production Systems ◽

Organic Production ◽

Tropical Region ◽

Conventional System ◽

Subtropical Region ◽

French Fry ◽

Tropical Regions ◽

Organic Systems ◽

Adequate Quality

This work evaluated the performance of potato clones for some agronomic and processing traits, in subtropical and high-altitude tropical regions, under conventional and organic production systems. Experiments were conducted in spring of 2017 and 2018 in Canoinhas-SC (subtropical), under the conventional system, and in winter of 2018 and 2019 in Brasília-DF (tropical), Brazil, under conventional and organic systems. Eleven advanced clones and cultivars Agata (fresh), Atlantic (chipping) and Asterix (French fry) were evaluated. RCBD with tree replications was used, and tuber yield and processing traits, plant vigor and cycle were evaluated. It was not possible to select high yielding and good processing quality clones with short cycle and less vigorous plants. It because higher yield and larger tuber size were attained by longer cycle genotypes, which had higher specific gravity, but darker frying color. The most outstanding clones differed with region and production system. For chipping, in the subtropical region, no clone had adequate quality, but in tropical F177-11-20 presented similar processing traits and higher or similar yield to 'Atlantic' in both systems, and also ORG7785 in organic. Comparing with ‘Asterix’, for French fry, in the subtropical region, superior or similar to the standard this cultivarwere F129-10-06 and F163-11-01; while in the tropical region and conventional system, were the clones ORG7785, F129-10-06, F163-11-01, F177-11-20, ORG6464, ORG 6377, F05-11-03, Odone 80-02 and F174-11-01; and in organicsystem, the best cloneswere F54-11-03, ORG7785, F129-10-06, F163-11-01, F177-11-20 and ORG6464.

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Influence of Shot Peening on the Isothermal Fatigue Behavior of the Gamma Titanium Aluminide Ti-48Al-2Cr-2Nb at 750 °C

Metals ◽

10.3390/met11071083 ◽

2021 ◽

Vol 11 (7) ◽

pp. 1083

Author(s):

Christoph Breuner ◽

Stefan Guth ◽

Elias Gall ◽

Radosław Swadźba ◽

Jens Gibmeier ◽

...

Keyword(s):

Residual Stresses ◽

Shot Peening ◽

Elevated Temperatures ◽

Stress Amplitude ◽

Negative Impact ◽

Fatigue Behavior ◽

Surface Hardness ◽

Fatigue Tests ◽

Positive Effects ◽

Isothermal Fatigue

One possibility to improve the fatigue life and strength of metallic materials is shot peening. However, at elevated temperatures, the induced residual stresses may relax. To investigate the influence of shot peening on high-temperature fatigue behavior, isothermal fatigue tests were conducted on shot-peened and untreated samples of gamma TiAl 48-2-2 at 750 °C in air. The shot-peened material was characterized using EBSD, microhardness, and residual stress analyses. Shot peening leads to a significant increase in surface hardness and high compressive residual stresses near the surface. Both effects may have a positive influence on lifetime. However, it also leads to surface notches and tensile residual stresses in the bulk material with a negative impact on cyclic lifetime. During fully reversed uniaxial tension-compression fatigue tests (R = −1) at a stress amplitude of 260 MPa, the positive effects dominate, and the fatigue lifetime increases. At a lower stress amplitude of 230 MPa, the negative effect of internal tensile residual stresses dominates, and the lifetime decreases. Shot peening leads to a transition from surface to volume crack initiation if the surface is not damaged by the shots.

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The Impact of Environmental Regulation on the Location of Pollution-Intensive Industries in China under Agglomeration Effect

International Journal of Environmental Research and Public Health ◽

10.3390/ijerph18084045 ◽

2021 ◽

Vol 18 (8) ◽

pp. 4045

Author(s):

Yinhao Wu ◽

Shumin Yu ◽

Xiangdong Duan

Keyword(s):

Environmental Regulation ◽

Local Economic Development ◽

Negative Impact ◽

Empirical Test ◽

Mediating Effect ◽

Production Costs ◽

Agglomeration Effect ◽

The Government ◽

Pollutant Discharge ◽

The Impact

Pollution-intensive industries (PIIs) have both scale effect and environmental sensitivity. Therefore, this paper studies how environmental regulation (ER) affects the location dynamics of PIIs under the agglomeration effect. Our results show that, ER can increase the production costs of pollution-intensive firms (PIFs) by internalizing the negative impact of pollutant discharge in a region, and thus, directly reduces the region’s attractiveness to PIFs. Meanwhile, ER can indirectly reduce the attractiveness of a region to PIFs by reducing the externality of the regional agglomeration effect. Moreover, these influences are regulated by the level of local economic development. Based on the moderated mediating effect model, we find evidence from the site selection activities of newly built chemical firms in cities across China. The empirical test shows that compared with 2014, the proportion of the direct effect of ER to the total effects significantly decreased in 2018, while the proportion of indirect effects under the agglomeration effect increased significantly. Our findings provide reference for the government to design effective environmental policies to guide the location choice of new PIFs.

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On-farm Development of Potato Production from True Seed in Indonesia

Experimental Agriculture ◽

10.1017/s0014479700022985 ◽

1992 ◽

Vol 28 (1) ◽

pp. 31-39 ◽

Cited By ~ 3

Author(s):

N. Gunadi ◽

M. J. Potts ◽

R. Sinung-Basuki ◽

Greta A. Watson

Keyword(s):

Production Systems ◽

Potato Production ◽

Production Costs ◽

Potato Seed ◽

True Potato Seed ◽

Yield Difference ◽

Tuber Crop ◽

On Farm ◽

Comparable Quality ◽

Better Than

SummaryThree seasons of on-farm experimentation to develop potato production from botanical or true potato seed (TPS) under cool fertile conditions in West Java, Indonesia, are described. Twenty-three farmers experimented with two production systems: use of transplants, and use of seedling tubers produced in nursery beds. There was little yield difference between the systems, but an apparent progeny × system × season interaction was observed. All progenies were more resistant to late blight than the present cultivars grown from tubers. Appropriate matching of progeny and system gave seed of comparable quality with, but total yields slightly less than, certified imported seed of cv. Granola. Ware quality was slightly better than that of cv. Granola. Production costs were markedly less than for a tuber crop, making TPS ideal for small, resource-poor farmers.

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A co-cultivation process of Nannochloropsis oculata and Tisochrysis lutea induces morpho-physiological and biochemical variations potentially useful for biotechnological purposes

Journal of Applied Phycology ◽

10.1007/s10811-021-02511-2 ◽

2021 ◽

Author(s):

Michele Maglie ◽

Costanza Baldisserotto ◽

Alessandra Guerrini ◽

Alessandra Sabia ◽

Lorenzo Ferroni ◽

...

Keyword(s):

Lipid Production ◽

Maximum Yield ◽

Pharmaceutical Products ◽

Nannochloropsis Oculata ◽

Production Costs ◽

Yield Reduction ◽

Total Biomass ◽

Tisochrysis Lutea ◽

Positive Effects ◽

Cell Extracts

AbstractThe biotechnological potential of microalgae has gained considerable importance in many applied fields: biomass production for food and feed, cosmeceutical and pharmaceutical products, energy and phytoremediation. The driving force that inspires the progress in microalgae production is the need for new cultivation systems to obtain simultaneously the maximum yield, reduction of water and nutrients use, and production of economically interesting molecules, such as pigments, fatty acids and polysaccharides. We aim to test, for the first time, the co-cultivation in saline medium of Tisochrysis lutea (Haptophyta) and Nannochloropsis oculata (Ochrophyta) to obtain valuable compounds, i.e. pigments and lipids characteristic of each species, using a single culture process. Mono-cultures of each strain were used as controls. The two strains showed an increase in the concentration of chlorophylls and carotenoids in co-culture. At the end of the experiment, the fatty acid profile was analysed by gas chromatography–mass spectrometry. The lipids in the co-cultivated cell extracts were mainly attributable to N. oculata, which represented 97% of the total cells (ca. 83% of the total biomass) at the end of the experiment. Nevertheless, the ω-3 characteristic of T. lutea (DHA and SDA, absent in N. oculata) was also detectable. Although the co-cultivation of these two phylogenetically different species of microalgae did not show positive effects on the growth and on the total lipid production, however, this process resulted in a reduction of the production costs and a lower consumption of water and nutrients.

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Predicting the potential distribution of the vase tunicate Ciona intestinalis in Canadian waters: informing a risk assessment

ICES Journal of Marine Science ◽

10.1093/icesjms/fsn054 ◽

2008 ◽

Vol 65 (5) ◽

pp. 788-794 ◽

Cited By ~ 37

Author(s):

Thomas W. Therriault ◽

Leif-Matthias Herborg

Keyword(s):

Risk Assessment ◽

Native Species ◽

Potential Distribution ◽

Negative Impact ◽

Ciona Intestinalis ◽

Environmental Niche ◽

Environmental Models ◽

Introduced Range ◽

Negative Impacts ◽

Almost All

Abstract Therriault, T. W., and Herborg, L-M. 2008. Predicting the potential distribution of the vase tunicate Ciona intestinalis in Canadian waters: informing a risk assessment. – ICES Journal of Marine Science, 65: 788–794. A crucial step in characterizing the potential risk posed by non-native species is determining whether a potential invader can establish in the introduced range and what its potential distribution could be. To this end, various environmental models ranging from simple to complex have been applied to predict the potential distribution of an invader, with varying levels of success. Recently, in marine waters, tunicates have received much attention, largely because of their negative impacts on shellfish aquaculture. One of these species is the vase tunicate Ciona intestinalis, which recently has had a negative impact on aquaculture operations in Atlantic Canada and could pose a risk in Pacific Canada. To inform the risk assessment of this species, we evaluated two different types of environmental model. Simple models based on reported temperature or salinity tolerances were relatively uninformative, because almost all waters were deemed suitable. In contrast, a more complex genetic algorithm for rule-set prediction (GARP) environmental niche model, based on documented Canadian occurrence points, provided informative projections of the potential distribution in Canadian waters. In addition to informing risk assessments, these predictions can be used to focus monitoring activities, particularly towards vectors that could transport C. intestinalis to these favourable environments.

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Effect of phenology on agonistic competitive interactions between invasive and native sheet-web spiders

Canadian Journal of Zoology ◽

10.1139/cjz-2015-0221 ◽

2016 ◽

Vol 94 (6) ◽

pp. 427-434 ◽

Cited By ~ 2

Author(s):

Jeremy D. Houser ◽

Adam H. Porter ◽

Howard S. Ginsberg ◽

Elizabeth M. Jakob

Keyword(s):

Competitive Advantage ◽

Native Species ◽

Negative Impact ◽

Relative Size ◽

Agonistic Interactions ◽

Resident Species ◽

The Third ◽

Linyphia Triangularis ◽

Size Interaction ◽

Very High

The phenologies of introduced relative to native species can greatly influence the degree and symmetry of competition between them. The European spider Linyphia triangularis (Clerck, 1757) (Linyphiidae) reaches very high densities in coastal Maine (USA). Previous studies suggest that L. triangularis negatively affects native linyphiid species, with competition for webs as one mechanism. We documented phenological differences between L. triangularis and three native species that illustrate the potential for the reversal of size-based competitive advantage over the course of the year. To test whether relative size influences interaction outcome, we allowed a resident spider to build a web and then introduced an intruder. We examined whether the outcomes of agonistic interactions over the webs were influenced by the species of the resident (invasive or native), the relative size of the contestants, and the species × size interaction. We found that the importance of relative size differed among species. In interactions between L. triangularis and each of two native species, size played a greater role than resident species on the outcome of interactions, suggesting that competitive advantage reverses over the season based on phenology-related size differences. Linyphia triangularis had a negative impact on the third species regardless of relative size.

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Production models of multiple products using a single machine under quality screening and reworking policies

Journal of Modelling in Management ◽

10.1108/jm2-06-2018-0086 ◽

2019 ◽

Vol 14 (1) ◽

pp. 232-259 ◽

Cited By ~ 10

Author(s):

Ata Allah Taleizadeh ◽

Mahshid Yadegari ◽

Shib Sankar Sana

Keyword(s):

Single Machine ◽

Manufacturing Systems ◽

Production Systems ◽

Production Costs ◽

High Tech ◽

Screening Process ◽

Automatic Production ◽

Content Type ◽

Economic Production ◽

Imperfect Items

Purpose The purpose of this study is to formulate two multi-product single-machine economic production quantity (EPQ) models by considering imperfect products. Two policies are assumed to deal with imperfect products: selling them at discount and applying a reworking process. Design/methodology/approach A screening process is used to identify imperfect items during and after production. Selling the imperfect items at a discount is examined in the first model and the reworking policy in the second model. In both models, demand during the production process is satisfied only by perfect items. Data collected from a case company are used to illustrate the performance of the two models. Moreover, a sensitivity analysis is carried out by varying the most important parameters of the models. Findings The case study in this research is used to demonstrate the applicability of the proposed models, i.e. the EPQ model with salvaging and reworking imperfect items. The models are applied to a high-tech un-plasticized polyvinyl chloride (UPVC) doors and windows manufacturer that produces different types of doors and windows. ROGAWIN Co. is a privately owned company that started in 2001 with fully automatic production lines. Finally, the results of applying the different ways of handling the imperfect items are discussed, along with managerial insights. Originality/value In real-world production systems, manufacturing imperfect products is unavoidable. That is why, it is important to make a proper decision about imperfect products to reduce overall production costs. Recently, applying a reworking strategy has gained the most interest when it comes to handling this problem. The principal idea of this research is to maximize the total profit of manufacturing systems by optimizing the period length under some capacity constraints. The proposed models were applied to a company of manufacturing UPVC doors and windows.

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