Loss Of Biodiversity Loss

972 Words4 Pages
Biological diversity defines according to article two of The Convention on Biological Diversity (CBD) which entered into force on 29 December 1993 as the variability among living organisms from all sources including, inter alia, terrestrial, marine and other aquatic ecosystems and the ecological complexes of which they are part; this includes diversity within species, between species and of ecosystems.
Many studies try to estimate the number of living species in the earth starting from 15,000 describe species and 500,000 estimated species (Poinar, 1983) then from 3–5 million (Tangley 1997) and 50 million (May 1998) then last but not least 11 million with around 18000 species described each year (Chapman 2009) .but all studies gives an estimation
…show more content…
Degradation" refers to a change of state with a negative value assessment that is related to subjectively chosen criteria (Perevolotsky and Seligman 1998).human effect on climate change will accelerate loss process, species abundance and distribution were shifted in the last thirty years due to climate change, also climate change can affect the distributional area of each species independently (Thomas et al 2004). Human activity include Industry, forestry, aquaculture, agriculture, fishing, mining, sediment and groundwater extraction, infrastructure development, introducing new species etc (Groom 2006). 60% of earth ecosystems are degraded (Markandya etal 2008). which will surly affect the number of living species and individuals that live in these ecosystems, but on the other hand Species extinction is a natural process (Groombrige 1992).that happened many times in the history, Economic processes in natural resources may increase losses of Biological diversity (Groombrige 1992). Travis 2003 in his research mention that the loss of habitat takes as random formula and there is no specific spatial correlation, but it appears that species with higher rates of colonization can tolerate the greatest degree of habitat…show more content…
The average minimum temperature starts from 5.6 ° C in the eastern desert to 19.8 ° C in the western area, while the maximum average varying from 18.7 to 31.3 ° C with average . On the other 25.3 °
Open Document