The present paper examined the relationship of population to the environment and with growing population, poverty and urbanization the environment is degrading. Conducted an analysis of changes and trends over last fifty years. The study reveals that the country's population growth is imposing an increasing burden on the country's limited and continually degrading natural resource base. The nat...

Crystal size distribution (CSD) in metamorphic rocks provide fundamental information about crystal nucleation and growth rate, growth time and the degree of overstepping. CSD data for garnet, staurolite, kyanite and andalusite crystals from the aureole demonstrate that the earliest formed of these minerals, garnet, has the highest population density and the shortest growth time. The last formed...

Individual base model of predator-prey system is constructed. Both predator and prey species have age structure and cohorts of early reproductive age have competitive advantage. The model has linear functional response in predation behavior and includes the effect of interference among predators and delay of population growth from resource intake, not by functional response but by calculation p...

Biological invasions, including infectious disease outbreaks and biocontrol introductions, often involve small numbers of individuals arriving in spatially heterogeneous environments. Small numbers lead to demographic stochasticity, and spatial heterogeneity means that establishment success depends critically on the introduction sites and movement patterns of invaders. We present a general stoc...

The population growth rate is linked to the distribution of age at death. We demonstrate that this link arises because both the birth and death rates depend on the variance of age-at-death. This bears the prospect to separate the influences of the age patterns of fertility and mortality on population growth rate. Here, we show how the age pattern of death affects population growth. Using this i...

Understanding if and how mutants reach fixation in populations is an important question in evolutionary biology. We study the impact of population growth has on the success of mutants. To systematically understand the effects of growth we decouple competition from reproduction; competition follows a birth-death process and is governed by an evolutionary game, while growth is determined by an ex...

introduction spatial studies as the main tools for the detailed study of all tangible and intangible aspects of regions have special ranks among all kinds of planning. the conformity of this organization with physical environment forms the spatial structure of which is usually observed as a distributed and isotropic spatial structure, focus and polar, unbalanced and haphazard, random and balanc...

In the turfgrass industry, the need for salinity tolerant turfgrasses is increasing because of the increased use of saline and non-potable water. Greenhouse container experiments were conducted to determine the relative salinity tolerance and growth responses of eleven native populations of tall fescue (Festuca arundinacea Schrub) (TF), including: Semirom, Mashhad, Sanandaj, Yasuj, Yazd Abad, D...

The problem of finding a longest increasing subsequence (LIS) is a well known task in sequence processing. There are many variants of the basic task. We discuss a recently introduced variant of LIS, a minimal height longest increasing subsequence problem and propose a new algorithm for it, which improves its time complexity. Moreover, we define a family of similar problems and introduce algorit...