the degradation is beyond threshold or future threats cannot be avoided (Lamb et al.
2005). In KMP, while implementing reforestation activities in the deforested areas,
natural regeneration, especially in the ex-burned areas, is also monitored to assess
whether in the future, full planting or at least, enrichment planting is still needed.
Three permanent plots (each 100 Â 100 m) were established in 2015 to study
natural regeneration in the areas which almost annually were impacted by fires. The
last fire incidence was in 2014, thus, the plots were established a year after the last
fire. Diameter at breast height and height of all remnant trees were recorded once a
year, while in the smaller subplots, the recruitment was tagged and monitored every
6 months. After 5 years measurements, we found out that the emergence of new
recruitment was not conspecific with the remnant trees, suggesting that the sources
of new regrowth might come from elsewhere (seed banks or the nearest forest
remnants). Only Campnosperma coriaceum species were abundant both as seedlings
and trees.
Moreover, since the initial monitoring, only the recruitment of pioneer species
(Melaleuca leucadendron, Melicope lunu-ankenda, and Syzygium sp.) dominated
the whole study area, reaching a peak of density in the third year of monitoring (up to
5167 recruitment/ha). However, in year three, their domination started to decline and
were replaced by more generalist species such as Campnosperma coriaceum,
Alstonia scholaris, and Ctenolophon parvifolius (density ranging from 300 to
800 seedlings/ha).
In addition, we also measured the emergence of woody species at larger areas
(three transects, each 220 m) in the sites where the last fire happened 3 years ago.
Our important value index calculations showed that once again, more generalist and
late successional species started to emerge in the third year after the fire although the
pioneer species were still abundant (Fig. 13.8).
Considering these findings, albeit a longer period of observation is still needed,
signs of natural recovery process are apparent. If fire can be excluded from this area,
using solely natural regeneration might become an option for the future of restoration. However, it is likely that enrichment planting is still needed to improve the
diversity of vegetation since the end target of this restoration is not only to establish
close canopy cover (Blackham et al. 2014; Page et al. 2009).
Moreover, we also recorded that the seedlings of Alstonia displayed high ability
to grow, providing a diameter and height increment rate of 0.3 cm/month and
4.36 cm/month, respectively. This was followed by Melaleuca leucadendron species
which has a diameter and height increment rate of 0.08 cm/month and 7.17 cm/
month, respectively. Its fast ability to grow vertically shows a typical characteristic
of pioneer species.
13.4.3 Hydrological Restoration
The main management intervention to reduce the greenhouse gas emission from peat
decomposition in KMP is rewetting the drained peatland. Rewetting can be
13 Management Practice and Restoration of the Peat Swamp Forest in. . .
399
2005). In KMP, while implementing reforestation activities in the deforested areas,
natural regeneration, especially in the ex-burned areas, is also monitored to assess
whether in the future, full planting or at least, enrichment planting is still needed.
Three permanent plots (each 100 Â 100 m) were established in 2015 to study
natural regeneration in the areas which almost annually were impacted by fires. The
last fire incidence was in 2014, thus, the plots were established a year after the last
fire. Diameter at breast height and height of all remnant trees were recorded once a
year, while in the smaller subplots, the recruitment was tagged and monitored every
6 months. After 5 years measurements, we found out that the emergence of new
recruitment was not conspecific with the remnant trees, suggesting that the sources
of new regrowth might come from elsewhere (seed banks or the nearest forest
remnants). Only Campnosperma coriaceum species were abundant both as seedlings
and trees.
Moreover, since the initial monitoring, only the recruitment of pioneer species
(Melaleuca leucadendron, Melicope lunu-ankenda, and Syzygium sp.) dominated
the whole study area, reaching a peak of density in the third year of monitoring (up to
5167 recruitment/ha). However, in year three, their domination started to decline and
were replaced by more generalist species such as Campnosperma coriaceum,
Alstonia scholaris, and Ctenolophon parvifolius (density ranging from 300 to
800 seedlings/ha).
In addition, we also measured the emergence of woody species at larger areas
(three transects, each 220 m) in the sites where the last fire happened 3 years ago.
Our important value index calculations showed that once again, more generalist and
late successional species started to emerge in the third year after the fire although the
pioneer species were still abundant (Fig. 13.8).
Considering these findings, albeit a longer period of observation is still needed,
signs of natural recovery process are apparent. If fire can be excluded from this area,
using solely natural regeneration might become an option for the future of restoration. However, it is likely that enrichment planting is still needed to improve the
diversity of vegetation since the end target of this restoration is not only to establish
close canopy cover (Blackham et al. 2014; Page et al. 2009).
Moreover, we also recorded that the seedlings of Alstonia displayed high ability
to grow, providing a diameter and height increment rate of 0.3 cm/month and
4.36 cm/month, respectively. This was followed by Melaleuca leucadendron species
which has a diameter and height increment rate of 0.08 cm/month and 7.17 cm/
month, respectively. Its fast ability to grow vertically shows a typical characteristic
of pioneer species.
13.4.3 Hydrological Restoration
The main management intervention to reduce the greenhouse gas emission from peat
decomposition in KMP is rewetting the drained peatland. Rewetting can be
13 Management Practice and Restoration of the Peat Swamp Forest in. . .
399