Kuraklığın Doğal Mera Alanları Üzerine Muhtemel Etkileri

Öz

Bir bölgede tarımsal üretim toprak koşulları, iklim ve bitki üçgenine bağımlı olarak şekillenmekte olup, o bölgede yetiştirilebilecek bitki türleri ve bu türlerin verimlilikleri üzerine bölgenin ekolojik koşulları, özellikle iklim faktörleri önemli derecede belirleyici olmaktadır. Uzun dönemlere ait ortalama yağış değerlerine göre, daha düşük yağışın gerçekleşmesi durumu olan kuraklık sonucu ortaya çıkan su kısıtlığı, insan, hayvan ve vejetasyonlar üzerine olumsuz etkilerde bulunmaktadır. Kuraklığa bağlı olarak verimdeki azalmanın yanı sıra vejetasyonunun tür kompozisyonu, kapalılık derecesi ve yem kalitesi de olumsuz yönde etkilenmektedir. Mera alanlarımızın büyük bir çoğunluğu yıllık toplam yağış miktarı düşük ve yağışın yıl içerisindeki dağılımı da düzensiz olan Doğu ve İç Anadolu bölgeleri gibi kurak veya yarı kurak olarak kabul edilebilecek bölgelerde bulunmaktadır. Bu gibi bölgelerde uzun süreli kuraklık meralarda verimi önemli ölçüde azaltmaktadır. Kuraklığa ilaveten zamansız ve ağır otlatma meraların hayvan otlatılarak değerlendirilemeyecek bir duruma gelmesine sebep olabilmektedir. Bu yüzden kurak dönemlerde otlatma uygulamalarının yeniden planlanması mera bitki örtülerinin devamlılığı açısından önem arz etmektedir.

Anahtar Kelimeler

• Mera,İklim faktörleri,Kuraklık

The Possible Effects Of Drought On Natural Pastures

Abstract

Agricultural production in a region, depending on soil conditions, climate and plant species is being shaped triangle, plant species that can be grown in the region and ecological conditions, especially climatic factors are significant determinants of the region on the productivity of this species. The drought is defined as lower rainfall values than the long-term average precipitation values, the water restriction that results from drought have negative effects on human, animal and plant vegetation. As well as the reduction in yield, species composition of the vegetation, canopy coverage and forage quality is also affected negatively due to drought. The majority of our rangelands are located in East and Central Anatolian regions considered as arid or semi-arid because in these regions annual total rainfall is low and rainfall distribution is irregular. In such areas, prolonged drought, the production of rangeland decreases significantly. In addition to drought, untimely and heavy grazing in the pasture can cause to come into a situation that cannot be evaluated animal grazing of rangelands. So rearrangement of grazing practices in during dry periods is important for the maintenance of pasture vegetation.

Keywords

• Rangeland,Klimatic factors,Rought.

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