الفهرس 
ClimateOnly 14 pages are availabe for public view
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Abstract
The p r e s e n t s t u d y p r o v i d e s an a n a l y s i s of t h e n u t r i e n t budget i n t h e ecosystem of two common s p e c i e s , Ammophila arenaria ( p e r e n n i a l g r a s s ) and Ononis v a q i n a l i s (subshrub), i n t h e h a b i t a t of c o a s t a l dunes of t h e w e s t e r n M e d i t e r r a n e a n c o a s t a l d e s e r t of Egypt, n e a r t h e v i l l a g e o f G h a r b a n i a t , a b o u t 50 Km west of A l e x a n d r i a . P l a n t m a t e r i a l , s t a n d i n g dead m a t e r i a l and s o i l were sampled every f o r t n i g h t d u r i n g 1978. P l a n t s with t h e i r s t a n d i n g dead m a t e r i a l were s e p a r a t e d i n t o t h e main o r g a n s . These o r g a n s and s t a n d i n g 0 dead m a t e r i a l were r i n s e d , o v e n - d r i e d a t 65 C and powdered f o r d e t e r m i n a t i o n of t h e i r c o n t e n t s of Na, K, Mg, Cu, Fe, Mn, Pand No E x t r a c t i o n of a v a i l a b e n u t r i e n t s i n two s o i l r e p l i c a s , 0.5 gm e a c h , was a c h i e v e d u s i n g d i f f e r e n t k i n d s of s o l u t i o n s f o r determi n a t i o n of t h e i r c o n t e n t s of n u t r i e n t s . Phytomass d e t e r m i n a t i o n s were based on t h e e s t i m a t i o n o f t h e c u m u l a t i v e i n c r e a s e i n l e n g t h o f l a t e r a l b r a n c h e s and l e a v e s . The i n c r e a s e i n l e n g t h was r e c o r d e d every two weeks. The phenological s t a g e s : v e g e t a t i v e , f l o w e r i n g , f r u i t i n g and dormancy, were a l s or e c o r d e d e v e r y two weeks f o r t e n i n d i v i d u a l s i n each sampling l o c a t i o n , and t h e a v e r a g e p h e n o l o g i c a l s t a t e of t h e p l a n t was c a l c u l a t e d . A model was c o n s t r u c t e d r e p r e s e n t i n g t h e a n n u a l n u t r i e n t f l u x ’ i n terms of t h e amounts u p t a k e n , how much of t h e s e amounts were r e t a i n e d by p l a n t o r g a n s