Agricultural Production Connectedness and Networks in Türkiye

Öz

The world’s population has been growing rapidly and since the 2006–2008 global food crisis, it has been questioned many times that how the world’s growing population will be fed properly. According to reputable international institutions, the world may be insufficient to supply enough food in the near future, and this fact may cause many economic, social, and government problems. In Türkiye, these problems will be realized more harshly than in peer countries for some reasons. Türkiye has one of the highest population growth rates in the world, while it hosts the highest number of refugees in the world. In addition, Türkiye’s agriculture sector has been experiencing a harsh downfall recently and the country has been dependent on importing food and agricultural commodities. Therefore, in this paper, I investigate the connectedness and networks of agricultural production in Türkiye by using the connectedness approach of Diebold and Yilmaz (2012, 2014), which is based on the forecast error variance decomposition methodology of generalized vector autoregressive models. I use Türkiye’s most produced agricultural commodity data, which are barley, wheat, rye, paddy, lentil, chickpea, and oat. The material consists of annual production data from 1938 to 2019. According to the analysis results, Türkiye’s agricultural production has been highly connected. Our findings show that production shocks arising from wheat and barley have spilled over to other commodities. Agricultural production networks and pairwise spillovers also exhibit a similar result that most of the commodities are highly interconnected to wheat and barley production. Besides, pairwise connectedness results show that there are some strong and weak connectivity relations, and these can be used for the decision-making process, risk aversion, and risk-seeking purposes. Our findings have important implications for policymaking for institutions, diversification, and risk management for producers, suppliers, and traders.

Anahtar Kelimeler

• Agricultural production
• Agricultural policymaking
• Network analysis
• Risk management
• Spillover effects

Türkiye’de Tarımsal Üretim Bağlantılılığı ve Ağları

Öz

Dünya nüfusu hızla artmakta ve 2006-2008 küresel gıda krizinden bu yana dünya nüfusunun nasıl doyurulacağı sorusu defalarca kez sorulmaktadır. Saygın uluslararası kuruluşlara göre, dünya yakın bir gelecekte yeterli gıdayı tedarik etmekte yetersiz kalabilir ve bu durum birçok ekonomik, sosyal ve devlet sorununa neden olabilir. Türkiye'de bu sorunların bazı nedenden dolayı benzer ülkelere göre daha sert bir şekilde gerçekleşeceğine inanılmaktadır. Türkiye, dünyadaki en yüksek nüfus artış oranlarından birine sahipken, dünyanın en fazla mülteciye ev sahipliği yapan ülkesidir. Buna ek olarak, Türkiye'nin tarım sektörü son yıllarda sert bir düşüş yaşamakta ve ülke gıda ve tarımsal emtia ithalatına bağımlı hale gelmektedir. Bu bağlamda, bu çalışmada, Vektör Otoregresif Modellerinin tahmin hata varyans ayrıştırma metodolojisine dayanan Diebold ve Yılmaz'ın (2012, 2014) bağlantılılık yaklaşımı kullanılarak Türkiye'deki tarımsal üretimin bağlantılılık ve ağları araştırılmaktadır. Çalışmada Türkiye’de en çok üretilen yedi tarımsal emtianın verisi kullanılmıştır. Bu ürünler; arpa, buğday, çavdar, pirinç, mercimek, nohut ve yulaf şeklindedir. Araştırmada kullanılan veri seti 1938 yılından 2019 yılına kadarki süreyi kapsayan tarımsal üretim verisidir. Analiz sonuçlarına göre, Türkiye'nin tarımsal üretimi yüksek oranda bağlantılıdır. Araştırmanın bulguları, buğday ve arpa kaynaklı üretim şoklarının diğer tarım ürünlerine de önemli ölçüde sıçradığını göstermektedir. Tarımsal üretim ağları ve ikili yayılmalar, emtiaların çoğunun buğday ve arpa üretimiyle yüksek oranda bağlantılı olduğu konusunda da benzer bir sonuç sergiler. Ayrıca, ikili bağlantılılık sonuçları, bazı güçlü ve zayıf bağlantı ilişkilerinin olduğunu ve bunların karar verme süreci, riskten kaçınma ve risk arama için kullanılabileceğini göstermektedir. Bulgularımızın kurumlar için politika oluşturma, çeşitlendirme ve üreticiler, tedarikçiler ve tüccarlar için risk yönetimi için önemli etkileri vardır.

Anahtar Kelimeler

• Tarımsal üretim
• Tarımsal politika
• Ağ analizi
• Risk yönetimi
• Yayılma etkileri

Kaynakça

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