SONUÇ VE ÖNER LER

Arazi kullan m ve toprak yönetimi topraklar n karbon ve azot içeri ini önemli ölçüde etkilemektedir. Çal lan topraklarda genel olarak organik karbonun önemli miktar 50 µm den küçük parçac klarda tutulmu tur. Karasal organik karbonun önemli bir k sm ise her iki kullan m alt nda da kil fraksiyonunda tutuldu u tespit edilmi tir. Arazi i leme hem kil hem de silt fraksiyonunda organik karbon miktar n n azalmas na neden olmu tur. Benzer ili ki toplam toprak azotu için de geçerlidir. Orman ve mera arazilerinde olu an bakir topraklar i lenen arazilerden daha fazla organik karbon ihtiva etmektedirler. Elde edilen sonuçlara göre çal ma alan nda organik madde, toprakta kil+ silt fraksiyonu ile ili kilidir ve topraklar n ince fraksiyonlar organik maddeyi olu turduklar organo-mineral komplekslerinde mikrobiyal parçalanmaya kar korumaktad r. nce fraksiyondaki organik madde miktar kültüvasyondan daha az etkilenmektedir. Özellikle kil fraksiyondaki organik karbon toprak i leme ile olu acak de i imlere kar daha dirençlidir. Arazi kullan m ndaki de i meler karasal karbon depolanmas n önemli ölçüde etkilemektedir. Dahas ülkemiz gibi ço u geli mekte olan ülkelerde nüfus art ile tar m alanlar nda önemli art lar olmu tur ve önümüzdeki elli y l içinde bu geni leme devam edecektir. Tar m, global ölçekte sera gazlar n n atmosfere sal n m nda çok önemli rol oynamaktad r. Bu yüzden modern tar m için karbonun toprakta al konmas ve atmosfere CO2 ak m n n azalt lmas çok önemlidir. Bu çal mada da gösterildi i gibi, birçok ara t rmada arazi kullan m sera gazlar n n atmosfere sal n m nda çok önemli etkiye sahiptir. Toprakta karbonun stabilizasyonunu sa layacak ve karbon sal n m n azaltacak i lemler sayesinde karasal ekosistemlerde karbon depolanmas art r labilir. Ülkemizin önemli bir bölümünde ve çal ma alan ndaki topraklar m zda ortalama organik karbon miktar Dünya ve Avrupa ortalamas ndan oldukça dü üktür. Bu nedenle ülkemiz topraklar nda iyi arazi yönetimi, global ölçekte, karbon tutulmas ve küresel s nma probleminin çözümüne katk sa layaca gibi, ayn zamanda toprak bozunmas n n önlenmesi ve topraklar m z n sürdürülebilir kullan m na çok önemli katk lar sa layacakt r. Bunun yan nda Kyoto Protokolü geli mekte olan ülkelere karbon emisyonunu azaltma art getirmektedir. Organik karbon depolanmas n art racak arazi i lemlerinin geli tirilmesi ile söz konusu protokolün gerekleri de yerine getirilerek, daha ya anabilir bir dünya için katk sa lanm olacakt r.

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