[Objective]The paper was to study the effect of continuous cropping on leaf nutrient and growth of different species of poplar plantation.[Method] The tree height,diameter at breast height(DBH),volume of different g...[Objective]The paper was to study the effect of continuous cropping on leaf nutrient and growth of different species of poplar plantation.[Method] The tree height,diameter at breast height(DBH),volume of different generations and species of poplar plantation in poplar production area in northern Jiangsu Province,as well as TN,TP and TK content in their leaves were determined through field investigation and indoor experiment.[Result] With the increasing generation,the changes of TN,TP and TK content in the leaves of different ages of two varieties of forest stand were also different.However,with the increasing tree ages,TN,TP and TK contents in leaves showed decrease trend.With the increasing generation,the changes of tree height of I-69 and I-72 poplar showed the similar trend.The effect of increasing generation on tree height of 7-year-old and 10-year-old poplar was relatively stable,showing decrease trend from generation to generation.The tree height of 4-year-old poplar first increased and then decreased with the increasing generation.The changes of DBH along with different generations were basically consistent with the changes of tree height.With the increasing cultivation generations,the volume of 7-year-old and 10-year-old poplar decreased with significant difference.[Conclusion ] The result provided basis for rational fertilization and management of poplar plantation,improvement of productivity of poplar plantation,and achievement of sustainable management of plantation.展开更多
In Malaysia, airborne hyperspectral remote sensing is a relatively new technique used for research and commercial value in forest inventory and mapping. An advantage of airborne remote sensing, compared to satellite r...In Malaysia, airborne hyperspectral remote sensing is a relatively new technique used for research and commercial value in forest inventory and mapping. An advantage of airborne remote sensing, compared to satellite remote sensing, is its capability of offering a very high spatial resolution images. Thus, UPM-TropAIR AISA's airborne hyperspectral imagery that has been used in this study provides great quantity, better quality and also lower cost in identifying, quantifying and mapping of the Malaysian tropical timber forest resources. For the first stage in this study, the development of spectral library is deemed required in order for the Spectral Angle Mapper (SAM) classification be used to separate and map individual tree species in a tropical mixed mountain forest of Gunong Stong Forest Reserve. Pre-processing, enhancement and interpretation of image were conducted using ENVI Version 4.0 software. Results indicated that a total of eight commercial timber tree species was identified and mapped in a study plot of 5 ha using the TropAIR airborne hyperspectral imager with the aid of ground truthings.展开更多
In order to study the fitting of some characteristics like low diameter at breast height (DBH), the height and height to the beginning of crown of the Oak species in two man-made and natural forests of this species ...In order to study the fitting of some characteristics like low diameter at breast height (DBH), the height and height to the beginning of crown of the Oak species in two man-made and natural forests of this species in north of Guilan's forests, Tooshi and Radarposhte forests were selected. A 100% inventory was done on a one-hectare sample plot in Tooshi man-made forests and on a two-hectare sample plot in Radarposhte natural forests. The results from this study showed that, in order to fit the diameter and the height of the Oak trees in man-made stands, Johnson's SB and normal statistical distributions have more capabilities and the three-parameter gamma and the three- parameter Weibull distributions are appropriate for diameters and heights of the natural Oak trees in Radarposhte forest, respectively.展开更多
基金Supported by National 948 Project(2011-4-63)Special Research Fund for Welfare Act of State Forestry(200904001-3)Youth Fund of Anhui Normal University(2009xqn73)~~
文摘[Objective]The paper was to study the effect of continuous cropping on leaf nutrient and growth of different species of poplar plantation.[Method] The tree height,diameter at breast height(DBH),volume of different generations and species of poplar plantation in poplar production area in northern Jiangsu Province,as well as TN,TP and TK content in their leaves were determined through field investigation and indoor experiment.[Result] With the increasing generation,the changes of TN,TP and TK content in the leaves of different ages of two varieties of forest stand were also different.However,with the increasing tree ages,TN,TP and TK contents in leaves showed decrease trend.With the increasing generation,the changes of tree height of I-69 and I-72 poplar showed the similar trend.The effect of increasing generation on tree height of 7-year-old and 10-year-old poplar was relatively stable,showing decrease trend from generation to generation.The tree height of 4-year-old poplar first increased and then decreased with the increasing generation.The changes of DBH along with different generations were basically consistent with the changes of tree height.With the increasing cultivation generations,the volume of 7-year-old and 10-year-old poplar decreased with significant difference.[Conclusion ] The result provided basis for rational fertilization and management of poplar plantation,improvement of productivity of poplar plantation,and achievement of sustainable management of plantation.
文摘In Malaysia, airborne hyperspectral remote sensing is a relatively new technique used for research and commercial value in forest inventory and mapping. An advantage of airborne remote sensing, compared to satellite remote sensing, is its capability of offering a very high spatial resolution images. Thus, UPM-TropAIR AISA's airborne hyperspectral imagery that has been used in this study provides great quantity, better quality and also lower cost in identifying, quantifying and mapping of the Malaysian tropical timber forest resources. For the first stage in this study, the development of spectral library is deemed required in order for the Spectral Angle Mapper (SAM) classification be used to separate and map individual tree species in a tropical mixed mountain forest of Gunong Stong Forest Reserve. Pre-processing, enhancement and interpretation of image were conducted using ENVI Version 4.0 software. Results indicated that a total of eight commercial timber tree species was identified and mapped in a study plot of 5 ha using the TropAIR airborne hyperspectral imager with the aid of ground truthings.
文摘In order to study the fitting of some characteristics like low diameter at breast height (DBH), the height and height to the beginning of crown of the Oak species in two man-made and natural forests of this species in north of Guilan's forests, Tooshi and Radarposhte forests were selected. A 100% inventory was done on a one-hectare sample plot in Tooshi man-made forests and on a two-hectare sample plot in Radarposhte natural forests. The results from this study showed that, in order to fit the diameter and the height of the Oak trees in man-made stands, Johnson's SB and normal statistical distributions have more capabilities and the three-parameter gamma and the three- parameter Weibull distributions are appropriate for diameters and heights of the natural Oak trees in Radarposhte forest, respectively.