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\hypersetup{pdftitle={Evaluation of Different Sampling Techniques for Volume Estimation of \textit{Acacia Nilotica} Stands in Blue Nile, Sinnar State, Sudan},pdfauthor={Osman Elsaid Adlan Abdelkareem, Yahia Ibrahim Mohammed Abutaba, Salih Omer Tutu, Ali mohamed Ali  Alsammani },pdfsubject={Tropentag 2016: Abstract},pdfkeywords={Acacia nilotica, Blue Nile, Sampling techniques, Volume estimation},pdfpagemode=None,colorlinks=true}
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\parbox[b]{13.4cm}{\centering \large{\textbf{Tropentag, September 18-21, 2016, Vienna, Austria}}\\[1ex] \Large{``Solidarity in a competing world ---\\fair use of resources''\\[2ex]}}
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\Large{\textbf{Evaluation of Different Sampling Techniques for Volume Estimation of \textit{Acacia Nilotica} Stands in Blue Nile, Sinnar State, Sudan\footnote{\textbf{Contact Address:} Osman Elsaid Adlan Abdelkareem, Institute of Gum Arabic Research and Desertification Studies, University of Kordofan, Elobied, Sudan, Institute of Gum Arabic Research and Desertification Studies, Institute of Gum Arabic Research and Desertification Studies, University of Kordofan Elobied Sudan P.o Box 160, 51111~Elobeid, Sudan, \mbox{e-mail}: \email{osmanraasta@yahoo.com}}\\[0.8ex]}}
\normalsize{\textsc{Osman Elsaid Adlan Abdelkareem$^{1}$, Yahia Ibrahim Mohammed Abutaba$^{2}$, Salih Omer Tutu$^{3}$, Ali mohamed Ali  Alsammani $^{4}$}}
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\begin{itemize*}
\item[]{\small{\textit{$^{1}$Institute of Gum Arabic Research and Desertification Studies, University of Kordofan, Elobied, Sudan, Institute of Gum Arabic Research and Desertification Studies, Sudan}}}
\item[]{\small{\textit{$^{2}$University of Kordofan, Sudan, Dept. of Forestry \& Range Sciences, Sudan}}}
\item[]{\small{\textit{$^{3}$University of Kordofan, Sudan, Dept. of Forestry \& Range Sciences, Sudan}}}
\item[]{\small{\textit{$^{4}$University of Kordofan , Dept. of Forestry and Range Sciences, Sudan}}}
\end{itemize*}
\index[author]{Abdelkareem, Osman Elsaid Adlan}
\index[author]{Abutaba, Yahia Ibrahim Mohammed}
\index[author]{Tutu, Salih Omer}
\index[author]{Alsammani , Ali mohamed Ali }
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\textbf{Abstract}
\begin{abstract}
\normalsize{
Abstract: This study was conducted at Elgazaier reserve forest, Singa Locality, Sinnar State, Sudan. The study aimed to distinguish appropriate sampling technique for volume estimation of \textit{Acacia nilotica} plantation based on accuracy and applicability. A total enumeration was carried out in compartment number three in an area of 26.46 hectare 15 years old. The real volume per hectare was calculated and compared with other volumes generated using four sampling techniques. The first; Circular sample with radius of \mbox{17.84\,m} equivalent to (\mbox{0.1\,ha}), second; quadratic sample with area (1000m$^{2}$) (\mbox{0.1\,ha}), strip sample (\mbox{0.5\,ha}) and six tree sampling method.  Trees attribute comprising Diameter at Breast Height (DBH) and average tree height in meters was measured. Data was collected and recorded in special forms including number of trees and remarks and entered and saved in excel worksheet and analysed using SAS software version 6.12. The results of the study revealed that there is a significant difference ($p < 0.0013$) between the tested sampling techniques. The circular sampling ranked at first (1.033) fallowed by quadratic sampling (1.0005), six tree sampling (0.855) and strip sampling (0.826), respectively. However, the results showed no significant difference between the first two sampling techniques in terms of accuracy but the first one is easy in application than the second one. The study recommended the circular sampling method in estimation of stand volumes for better results and less time consuming, the strip sampling method scored the lowest values in ranking but it's still recommended for natural stands assessment because it gives more chances to accommodate different species particularly in the assessment of biodiversity. }

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\end{abstract}
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\noindent \textbf{Keywords:} \textit{Acacia nilotica}, Blue Nile, Sampling techniques, Volume estimation
\index[key]{Acacia nilotica@\textit{Acacia nilotica}}
\index[key]{Blue Nile}
\index[key]{Sampling techniques}
\index[key]{Volume estimation}
\end{document}
