Comparison of Stand Density Measures as Predictor of Diameter Increment

Abstract

Seven expressions of stand density were compared in regard to overstory tree diameter increment in eastern cottonwood (Populus deltoides Bartram ex Marsh.)-silver maple (Acer saccharinum L.)-American sycamore (Platanus occidentalis L.) forests. Basal area (BA), trees per hectare (TPH), percent stocking, stand density index (SDI), relative minimum density of full site occupancy (R_MDFO), percent average maximum density (P_AMD) and relative density (RD) were evaluated as expressions of stand density. Relative stand density measures seemed to be better predictors of average diameter increment than absolute density measures. In addition, relative density measures were identical in regard to their influence on the tree diameter increment.

Keywords

• absolute measures,basal area,relative measures,diameter increment,stocking

Meşcere Sıklığı Ölçü Birimlerinin Çap Büyümesini Tahmin Etme Yönünden Karşılaştırılmaları

Öz

Yedi adet meşcere sıklığı ölçü birimi, Doğu kavağı (Populus deltoides Bartram ex Marsh.)-gümüşi akçaağaç (Acer saccharinum L.)-Amerikan çınarı (Platanus occidentalis L.) ormanlarındaki ağaç çap büyümesini tahmin etmeleri yönünden karşılaştırılmıştır. Göğüs yüzeyi alanı (BA), hektardaki ağaç sayısı (TPH), yüzde sıkışıklık, meşcere sıklık indeksi (SDI), tüm alan doluluğunun minimum nispi sıklığı (R_MDFO), ortalama maksimum sıklık yüzdesi (P_AMD) ve nispi sıklık (RD) meşcere sıklığını ifade etmeleri bakımından değerlendirilmiştir. Nispi meşcere sıklık ölçü birimlerinin ağaç çap büyümesini  tahmin etme bakımından mutlak sıklık ölçü birimlerine nazaran daha başarılı oldukları saptanmıştır. Ayrıca, nispi meşcere sıklık ölçü birimlerinin ağaç çap büyümesine olan etkileri bakımından kendi aralarında benzer oldukları tespit edilmiştir.

Anahtar Kelimeler

• absolute measures,basal area,diameter increment,relative measures,stocking

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