แก๊สไนโตรเจนมีบทบาทความสําคัญอย่างไร

��ਹ��ʷ�辺�ҡ㹺��ҡ�Ȣͧ�š��ҳ 78% ��ѧ��ͧ��Сͺ�Ӥѭ�ͧ��š�� õչ ��Թ �ô��Ǥ��ԡ ��ع��¹�ͧ��ਹ㹺��ҡ�� ժ��Ե��ѯ�ѡ��ਹ�դ��Ӥѭ��ͧ�ҡ�繡�кǹ�� ¹�ŧ��š�Ţͧ��ਹ��š��蹷��Ѻ��ժ��Ե��Դ��ҧ� ��ö��š��ҹ�鹹�� ֧�Դ��¹�ŧ��š�� ͧ�ҡ��ԡ��͡��പѹ-�մѡ�ѹ ��ͧ �ʴ��ѧ��

��Ҩо��÷��Դ��Ҩҡ��кǹ��¹�ŧ��š�Ţͧ ��ਹ��ҡ��ѯ�ѡ��ਹ�»�� ਹ��š�ŷ��ִ�ѹ��¾ѹ�� ֧��ਹ��ӻ�ԡ��ҧ�� Ѻ��š�� ժ��Ե�֧��ö��ਹ�� 觨��դ��Ǣ�ͧ�Ѻ�� ҧ��Ҩ��ѹ ��͹��Ҩ��ѧࡵ��ѯ�ѡ��ਹ�ա�кǹ��¹�ŧ��ҧ�ú�ҧ �ʴ��ѧ�ٻ��1

�ѯ�ѡ��ਹ

��кǹ��÷��Ӥѭ��ѯ�ѡ��ਹ

1. fertilizer ��÷�� ŧ�㹴Թ��ԭ�Ժⵢͧ�ת

2. volatilization �� ö��¹��«��ʷ��Ŵ��ҡ��

3. animal wastes ��觻�ԡ�ŷ��Ҩҡ�ѵ��ŧ�㹴Թ ��ż�Ե

4. organic matter �ҡ�ת�ҡ�ѵ�� 㹴Թ

5. immobilization �ҵ�͹Թ�� ਹ �� ʿ�� ١��ժ��Ե��Ҵ��¹��Թ��

6. nitrification ��¶١��¹��õ ��Ấ��㹴Թ

7. biological fixation �� nitrogen fixation �ת��С�Ŷ�� ö��֧��ਹ��ͧ�ҡ��Ấ�� 㹻��ҡ�� Ấ��Ѻ��ٻ��õ�ҡ�ת 㹷ҧ��Ѻ�ѹ Ấ��ਹ ��¹��ٻ��Թ�� 觾ת��ö��

8. mineralization ��û��ҧ�� ҡ��ժ��Ե

9. denitrification ��õ �١��¹��ٻ��ਹ , 乵��͡䫴� , 乵�ԡ�͡䫴��Ấ��㹴Թ ��ʹԹ��¡

10. crop uptake and removal ��٭��¢ͧ��èҡ�к��Ǽż�Ե�͡�ҡ��鹷��л�١

nitrification �Դ��ԡ��͡��പѹ �ҡ��·��١��Ấ�� ÷� (NO2-) ��õ (NO3-) �ת��Ấ��ö�ӨѴ��ͧ�� ͹��÷� �� õ �մѡ�� ¨��¹�ٻ��繡ô��¾ת��ͧ �ѵ��СԹ�ת��觢ͧ�õչ ��ժ��Ե��õչ��ҹ�鹡�С�Ѻ��㹴Թ ��Դ��ҧ ��õ�֧��ਹ��ਹ㹺��ҡ��Ấ��«��¹ nitrate �� nitrogen ��͡��ਹ�ͧẤ�� ¡�� кǹ�� denitrification

��š�ŷ��Դ��ѯ�ѡ��ਹ

1.N2
��ਹ��ٻ��

2.NH3
��·��ٻ��Դ�ҡ��ժ��Ե �� 觻�ԡ�� ͺ��ǳ��˹�Ңͧ��

3.N0
乵�ԡ�͡䫴쾺��㹺��ҡ�ȫ��Ҩҡ��кǹ�� denitrification �� кǹ��ص��ˡ��

4.NH4+
��͹ ��㹴Թ��ö�ٴ��¾ת ��͹��ǹ�˭��¹��õ

5.N20
乵��͡䫴� ��ٻ�ͧ��ʾ��㹺��ҡ�� Ҩҡ��кǹ�� denitrification �� С�кǹ��ص��ˡ��

6.NO3-
��õ ��㹴Թ ��ö�١�ٴ��¾ת �� ¨ҡ�Թ��ǹ�ͧ�ҡ

˹�ҷ��ͧ��ਹ

��û�Сͺ��ਹ��辺��ͧ͢�ת�շ�駷��觴ٴ��ѧ��¹�ŧ�Ѻ�Թ��ë��ա��ѧ��ҡ��÷ ��·��ת�ٴ�� Թ��÷��ਹ��ͧ��Сͺ�Ҩ�� 6 ��

1. �õչ (proteins) ��Сͺ��¡ô�� (amino acids) ��Դ��ҧ � ��§�ѹ��ҧ��ẺἹ �� 50 �֧ 100 ˹�� ¡ô��ҹ��ѹ��¾ѹ��ྻ䷴� (peptide bond) �õչ��˹�ҷ��Ӥѭ�ҡ��ͧ��Сͺ��ç��ҧ�ͧ
      (�) �ⷾ�ҫ��
      (�) ��繷��ç��ҧ��о��㹡��͹��ü�ҹ��
      (�) �͹�� ˹�ҷ��觻�ԡ��Ҫ��ը֧�պ��ҷ��Ǣ�ͧ�Ѻ��᷺��ԫ��ҧ��ҧ��ҧ

2. �ô�� ਹ�� (amino group) �ô��˹��ç��ҧ (building blocks) �ͧ�õչ �µ��§�ѹ��ҧ��ẺἹ �͡�˹�ͨҡ�ô��⹷��ç��ҧ�ͧ�õչ�� ѧ��ա�ҡ��ҧ�� Ѵ��ǹ�ͧ�ô��ҧ �ô��СѺ�ô��ç��ҧ�ͧ��õ�ҧ � ��ѡɳ�੾�Тͧ�ת��Ъ�Դ

3. ��ת ��ת�ѧ��ͧ��ਹ��ͧ��Сͺ �� ͡�Թ (auxins) �Ѻ��䤹Թ (cytokinins) �ô�Թ��ͫԵԡ (indole-3-acetic acid, IAA) ��͡�Թ��ת�ѧ��ҡ�ô��⹪��ͷ�Ի�࿹ (tryptophane) ��ҷ��Ӥѭ�ͧ IAA ��͡��ԭ�Ժⵢͧ�ת �� е�鹡�� 觡�â��¢�Ҵ�� Ǻ��ᵡ�ҡ �Ѻ��駡��ԭ�ͧ�Ң�ҧ ��ͧ�ѹ��ǧ�ͧ� ��м� ��䤹Թ��ת�� â��¢�Ҵ�� ҧ��С��ԭ�ͧ�� 㹡�ç͡�ͧ�� ҧ�õչ ��ͤ�� (senescence) ��ͧ��Сͺ�ҧ�� 6-(4-hydroxy-3-methyl-trans-2-butenylamido) Purine ��Ѻ��䤹Թ��辺㹾ת��ҧ � ��ǹ��͹ؾѹ��ͧ isopentenyl adenine

�ٵ��ç��ҧ�ͧ auxins

�ٵ��ç��ҧ�ͧ cytokinins

4. �ô��Ǥ��ԡ (nucleic acids) �� 2 ��Դ �� ribo nucleic acid (RNA) ��˹�ҷ��Ǣ�ͧ�Ѻ��ѧ��õչ �� deoxyribo nucleic acids (DNA) ��˹�ҷ��ٹ��ŷҧ�ѹ�ء��

�ٵ��ç��ҧ�ͧ DNA �� RNA

5. ��û�Сͺ��ਹ�� д�⹫չ�ÿ��࿵ (adenosine triphosphate, ATP) ��͹�� (Co-enzymes) �� NAD (nicotinamide adenine dinucleotide) �� NADP (nicotinamide adenine dinucleotide phosphate)

6. ��û�Сͺ��ਹ��ת�� (reserves) ��ͷ�˹�ҷ��ͧ�ѹ (protective compounds) �� Ť��´� (alkaloids) ��ҧ�ͧ��Ť��´��ѡ�ѹ��ҧ��ҧ��ҧ �� ⤵Թ (nicotine) �ҡ��ٺ ��չ (morphine) �ҡ��