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1.
Environ Manage ; 52(2): 514-30, 2013 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-23665757

RESUMEN

The requirement to assess the management effectiveness (ME) in protected areas (PAs) is increasing around the world to help improve management and accountability. An evaluation of ME for Khojir National Park (KNP), one of the Iran's oldest PAs, was conducted using a multi-method approach that consisted of structured interviews, open interviews, and site visits. This was the first ME evaluation in Iran. The structured interview was based on the management effectiveness tracking tool methodology. KNP received an average score of 43 %, which is lower than the global average, illustrating that its general management was in the low-intermediate level. The indices of legal status, resource inventory, planning for land and water use, regulations, and objectives received the highest average scores, whereas education and awareness, community co-management, regular work plan, boundary demarcation, visitor facilities, budget sources, staff training, protection systems, and management plan received the lowest ones. The management system of KNP was generally established, but many problems of the management still need to be resolved. To improve ME, some countermeasures should be taken, such as increasing funding, strengthening capacity building, planning, and adaptive management, and implementing community participation.


Asunto(s)
Conservación de los Recursos Naturales , Recolección de Datos , Humanos , Irán , Responsabilidad Social
2.
Environ Manage ; 50(4): 750-65, 2012 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-22797765

RESUMEN

Since the 1950s, there has been a continuous increase in the number and coverage of protected areas (PAs) in Iran, and in total 253 PAs have been declared that cover 10.12 % of the country's area. This paper reviews literature addressing Iran's PAs, examines what is known about them, highlights the challenges and lessons learned, and identifies areas where more research is needed. The PA system in Iran is criticized because of (1) shortages of manpower, equipment, and financial resources; (2) de jure PAs that are often implemented as de facto reserves; (3) lack of national biodiversity indicators and objective monitoring processes; and (4) limited public participation and conflict between people over PAs. To improve, Iran's PAs system needs to be realistically supported by policies and planning instruments. In addition, the implementation of active management to restore habitat, increase education and awareness, shift practices towards the guidelines of international organizations, build capacity, and improve management and co-management by local communities needs to occur.


Asunto(s)
Biodiversidad , Conservación de los Recursos Naturales , Conflicto Psicológico , Conservación de los Recursos Naturales/economía , Conservación de los Recursos Naturales/métodos , Monitoreo del Ambiente , Humanos , Irán
3.
Anim Sci J ; 88(2): 222-230, 2017 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-27346211

RESUMEN

Although non-destructive deformation is relevant for assessing eggshell strength, few long-term selection experiments are documented which use non-destructive deformation as a selection criterion. This study used restricted maximum likelihood-based methods with a four-trait animal model to analyze the effect of non-destructive deformation on egg production, egg weight and sexual maturity in a two-way selection experiment involving 17 generations of White Leghorns. In the strong shell line, corresponding to the line selected for low non-destructive deformation values, the heritability estimates were 0.496 for non-destructive deformation, 0.253 for egg production, 0.660 for egg weight and 0.446 for sexual maturity. In the weak shell line, corresponding to the line selected for high non-destructive deformation values, the heritabilities were 0.372, 0.162, 0.703 and 0.404, respectively. An asymmetric response to selection was observed for non-destructive deformation, egg production and sexual maturity, whereas egg weight decreased for both lines. Using non-destructive deformation to select for stronger eggshell had a small negative effect on egg production and sexual maturity, suggesting the need for breeding programs to balance selection between eggshell traits and egg production traits. However, the analysis of the genetic correlation between non-destructive deformation and egg weight revealed that large eggs are not associated with poor eggshell quality.


Asunto(s)
Pollos/genética , Pollos/fisiología , Oviposición/genética , Oviposición/fisiología , Carácter Cuantitativo Heredable , Animales , Cruzamiento , Cáscara de Huevo , Huevos , Femenino , Selección Genética , Maduración Sexual
4.
J Poult Sci ; 53(4): 249-256, 2016 Oct 25.
Artículo en Inglés | MEDLINE | ID: mdl-32908391

RESUMEN

Several conventional traits, including eggshell thickness, are commonly being improved genetically as a means to increase eggshell strength. At the same time, researchers have come to recognize that factors related to egg geometry, such as egg shape, are important determinants of the variability remaining in eggshell strength, after conventional traits have been considered. Therefore, given that the value of the egg shape index -the egg's width to length ratio-depends highly on the hen strain, it is necessary to examine the relationship between eggshell strength and shape index more closely in a variety of breeds. From this perspective, by using REML methodology under a five-trait animal model, we analyzed a two-way selection experiment for non-destructive eggshell deformation in 31 generations of White Leghorns, to evaluate the effect of selection for eggshell strength on egg shape. In the strong line, which refers to the line that was selected for decreased non-destructive deformation value, the genetic correlation between eggshell breaking strength and shape index was 0.285±0.055, whereas that between non-destructive deformation and shape index was -0.021±0.063. In the weak line, these values were 0.244±0.055 and -0.093±0.060, respectively. The heritability estimates were 0.381±0.033 for non-destructive deformation, 0.349±0.029 for eggshell breaking strength, and 0.544 ±0.027 for shape index in the strong line, and 0.408±0.031, 0.468±0.032, and 0.484±0.028, respectively, in the weak line. The genetic correlation between eggshell breaking strength and shape index suggests that rounder eggs are somewhat more resistant to breakage than more elongated eggs. The moderately high heritability estimates for shape index indicate the potential to improve egg shape through genetic gain.

5.
Ecol Inform ; 6(3): 177-186, 2011 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-32362804

RESUMEN

Simulating epidemics in metapopulations is a challenging issue due to the large demographic and geographic scales to incorporate. Traditional epidemiologic models choose to simplify reality by ignoring both the spatial distribution of populations and possible intrapopulation heterogeneities, whereas more recent solutions based on Individual-Based Modeling (IBM) can achieve high precision but are costly to compute and analyze. We introduce here an original alternative to these two approaches, which relies on a novel hybrid modeling framework and incarnates a multiscale view of epidemics. The model relies on a technical fusion of two modeling paradigms: System Dynamics (SD) and Individual-Based Modeling. It features an aggregated representation of local outbreaks rendered in SD, and at the same time a spatially-explicit simulation of the spread between populations simulated in IBM. We first present the design of this deterministic model, show that it can reproduce the dynamics of real resurgent epidemics, and infer from the sensitivity of several spatial factors absent in compartmental models the importance of having large-scale epidemiological processes represented inside of an explicitly disaggregated metapopulation. After discussing the implications of results obtained from simulation runs and the applicability of this model, we conclude that SD-IB hybrid modeling can be an interesting choice to represent epidemics in a spatially-explicit way without necessarily taking into account individual heterogeneities, and therefore it can be considered as a valuable alternative to simple compartmental models suffering from detrimental effects of the well-mixed assumption.

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