Agroforestry of bamboo in Tana Toraja, Indonesia (a way combining plants inherited from ancestors)

Bamboo plants are known as “renewable resources” and have high abundance, high biomass production that have economic and ecological value. Tana Toraja Regency is one of the tourist destinations in Indonesia which has culture that is very familiar with bamboo. There is the highest variety of bamboo species both common and endemic, that is supported by nature. Bamboo plant in an intercropping system with agricultural, forestry and plantation crops. The agroforestry system has long developed, that is a way of planting the ancestors. The structure of agroforestry stands with species of agricultural and plantation crops, by using descriptive methods, namely timber trees 22.2%, bamboo clumps 11%, plantation trees 37% and medicinal trees or vegetable 29.8%. A high proportion of timber trees and plant structure density were formed, consisting of 42 plant species divided into 4 strata. The density level (K) of Petung bamboo reaches 10-20 clump per hectare, which is below that of Tallang bamboo. The association within stand structure namely bamboo, sugar palm, uru and suren. Based on the structure for the further development of bamboo shoots, it is necessary to regulate the spacing between plants to achieve a balance in increasing the yield of commodity.


Introduction
Bamboo plants are known as "renewable resources" and have a high abundance.Leelatanon et al. [1] stated that the advantages of bamboo compared to wood, namely that it can grow faster than wood, can reduce environmental pollution because it absorbs Nitrogen (N) and Carbon Dioxide (CO2) is quite high.This is because it has distinguished properties, including high tensile strength to weight ratio, low cost, abundant availability, and environmental-friendly characteristics.Bamboo as a major non-wood forest product and the main substitute of wood, bamboo is of increasing interest to ecologists owing to its rapid growth and correspondingly high potential for mitigating climate change.With a long history of production and utilization of bamboo, China is one of the countries with the richest bamboo resources and largest area of bamboo forest, and has paid unprecedented attention in recent decades to management of its bamboo forests [2].Furthermore, Setiawan and Hayati [3] said that the agroforestry system in Tana Toraja Regency and North Toraja Regency is to be able contribute to climate change mitigation by absorbing CO2 gas in the atmosphere of 525.61 tons/ha.The average value of total carbon storage at the age of 7 years was 21.88 tons/ha, at 13 years at 131.78 tons/ha and at 22 years at 165.44 tons/ha.The increase in the value of carbon storage is in line with the increase in the age of the stand.In addition to functioning ecologically, bamboo plants also have economic value, bamboo has an aesthetic value with a natural, smooth and colour demeanours beautiful without needing to be painted.
Bamboo that is felled at an old age has a slender shape straight and easy to pack.In addition, bamboo has a relatively cheap price compared to bamboo another building material because it grows in many places and the annual production is sufficient abundant, non-polluting, environmentally friendly and can grow with little water [4].
The agroforestry system has long been developing in Tana Toraja Regency and North Toraja Regency, has become a common model among landowners for bamboo intercropped with Agriculture, Forestry and Plantation crops.Based on the distribution, structure and species planted, it is classified as a simple agroforestry system based on bamboo plants.Simple agroforestry, in which trees are intercropped with one or more annual plant species.
Community forests have great potential both in terms of tree population and the number of homes that cultivate them.Community forests are expected to be able to contribute significantly to the reduction of national greenhouse gases.Based on this, it is necessary to conduct research to determine the potential for carbon storage in Uru-based community forest stands [5].
The agroforestry system is also able to have a positive impact on soil fertility, especially when using trees and shrubs of the legume type which provide a mechanism for supplying nitrogen through biological fixation.In addition, agroforestry systems can have a positive effect on invertebrate and microorganism populations so that they can play a greater role in the agro ecosystem [6].Agroforestry is assessed to be capable of being one of the solutions to solve forest problem.One of the units which was most widely applied of the agroforestry cropping pattern shaped a composition which is tied to each other between the components cropping pattern is Kesatuan Pengelolaan Hutan Lindung Batutegi (KPHL) [7].Important factors in agroforestry that influence the effectiveness of nutrient cycling processes in soil productivity include the high proportion of annual woody plants present, the frequency and method of harvesting their products, the structure and density of the root system, the type and magnitude of disturbance (including management).to the system and spatial arrangement and time of presence of plant species [8].
This study aims to determine the structure and density of agroforestry plants on bamboo fields in Tana Toraja and North Toraja districts.

Location of Research and Implementation Time
The research was conducted in Kab.Tana Toraja, in Mapongka Village, Mengkendek District, around KHDTK Mengkendek, Ariang Village and Sikolong Village, Makale District, Tana Toraja District and To'kumila Village, Soluara District, North Toraja Regency.The three locations are included in the administrative area of KPH Saddang II, South Sulawesi Provincial Forestry Service.
The research was conducted for 8 months, namely April -December 2019.The topographic conditions in the district.Tana Toraja is at an altitude of 800-1200 m above sea level and Kab.North Toraja, which has climate type A, has an annual rainfall of 2,252 mm-2,500 mm per year.As for the location for data collection on agroforestry land which was dominated by stands of bamboo and clove plants intercropped with several types of forestry trees and agricultural plants.The figure above shows the amount of rainfall of 2666,6 mm in 2017.The amount of rainfall in 2017 was quite high, but the frequency of rainfall was uneven, unlike the previous rainy season, namely in 2016, so it had a huge impact on microclimatic conditions.

Data collection method
The methods used in this study were interviews and direct field observations on agroforestry plots in a purposive manner, namely by deliberately placing them on land dominated by bamboo stands.The area of the observation plots at each location was based on 10% of the area and the placement of plots within the area was carried out by systematic sampling.If the area of observation is > large again (up to 2 hectares) nested sampling is used to reduce deviations.
Other data collection was based on the results of interviews and direct observation, interviews were conducted by question and answer using questionnaires and direct observation was carried out by collecting data on plant composition by noting the types of plants, both trees, annuals and shrubs and undergrowth plants that exist and have economic value in a demonstration plot of 0 .5 (5,000 m 2 -1 hectare (10,000 m 2 ).

Implementation Technique
Recording is done in a tally sheet, grouped by location of data collection, namely: -Location A consists of 4 observation plots in Mapongka village, Tana Toraja district (each plot area is 1.5 hectares) -Location B consists of 4 observation plots in Ariang village, Tana Toraja district (each area is 0.75 hectares) -Location C consists of 4 observation plots in Sikolong village, Tana Toraja district (each area is 0.75 hectares) -Location D consists of 4 observation plots in To'kumila village, North Toraja district (each plot area is 1 hectare) -Location E consists of 4 observation plots in To'kumila village, North Toraja district (each plot area is 1 hectare) The name of species uses local names and the respective stages of regeneration, i.e. the tree, pole and sapling stage is measured for diameter at breast height using a diameter tape and the rejuvenation stage of the tillers/seedlings is measured by the basal area of the canopy closure area 2.2.2.Un-known species and unknown botanical names were prepared in the form of a 2-framed herbarium and then identified in the ecology laboratory, Forestry Faculty, Hasanuddin University.

Data Analysis
Data on vegetation types is recapitulated according to the location/demplot number recorded and then the number is calculated according to the rejuvenation rate of trees, poles, saplings, and seedlings.The total number of observation plots is 17 plots.Parameters observed in each plot were the number of similar trees, height, and diameter.For bamboo clumps, the diameter of the clump and the number of stems per clump were measured.Recorded in the observation tally sheet for further recapitulation and analysis.▪ The results of observations include the name of the species, the number of individuals per species, and plant height tabulated and then analyzed descriptively.▪ Data related to natural characters are collected in the form of primary and secondary data from the results of laboratory tests that have been carried out previously.

Results and Discussion
Based on the results of analysis on bamboo agroforestry land, 45 plant species were found in 5 locations.
Based on the distribution, structure, and types of observations in 2019 on agroforestry land in 2 districts, the system used is a simple agroforestry system based on bamboo plants.Based on the number of each type of tree, data was obtained that clove trees were found in location A, B and land C. Based on this it seems that there is a tendency for owners to pay more attention to clove plants, both through maintenance (fertilizing and cleaning the branches and cleaning under the trees).Is it because the price of cloves is currently increasing?when compared with the prices of other commodities or in terms of the age of the young plants on land A, they differ in age from the clove plants on location B and C, so they require intensive maintenance.Meanwhile, for groups of bamboo species such as Ampel, Petung, Tallang and Parring bamboo, which are inherited from their predecessors (parents, grandmothers and so on), the density level is sufficient in all observed areas, except for black bamboo, which has the lowest density level, which is only 3.3 clumps/ha and found in plots adjacent to the KHDTK area.In relation to the culture of the Toraja people, there are plants that are characteristic of the local culture such as uru (Emerillia ovalis), buangin (Casuarina junghuhniana) and pangi trees (Pangium edule) which have a high to low density level, lower than the aren (Arenga pinnata) with a high density level of 3.3 -66.6 trees per hectare and suren (Toona sureni) has a density of 6.6 to 56 trees per hectare.The suren wood is an integral material in the construction of traditional Toraja houses, so its regeneration continues.In addition, the sap from the palm tree is filtered and a special drink is made.Types of fruit that were also found in the observation plots were soursop (Annonna muricata) and tamarillo/markisa Belanda (Solanum betaceum) plants with a low density of 3.3 trees per hectare.).Carpentry wood susch as mountain pine whose wood is relatively strong and straigth, suren, pine and uru wood are the main ingredients for Toraja traditional houses.Meanwhile, the types of petung, tallang and ampel bamboo are used as ingredients for the huts during the Rambu Tuka (thanksgiving event) and Rambu Solo (mourning event).

Conclusion
There are mixed plant of 42 species found growing and thriving on simple agroforestry lands in Tana Toraja and North Toraja districts.Dominated by types of forestry and plantation crops, bambu plants were not dominant either in the observation plots or in each location.The availability of uru, buangin, suren and aren is quite high and these types are key plant species for the Toraja people, because they are related to culture.Likewise, fruit plants such as markisa Belanda and terong Belanda fruit are a characteristic drink for the Toraja people besides palm wine which comes from aren as body warmer.

Figure 1 .
Figure 1.The average of rainfall total in the last 7 years at the Toraja research location

Figure 2 .
Figure 2. The structure agroforestry plant at A location

Figure 3 .
Figure 3.The Structure of agroforestry plant at B location In Figures 2 and 3, the structure of agroforestry plants at location A (Mapongka village) and location B (Ariang village) are shown the dominance of carpentry plants is balanced with fruit plants as well as bamboo groves (Tabel 1).Carpentry wood susch as mountain pine whose wood is relatively strong and straigth, suren, pine and uru wood are the main ingredients for Toraja traditional houses.Meanwhile, the types of petung, tallang and ampel bamboo are used as ingredients for the huts during the Rambu Tuka (thanksgiving event) and Rambu Solo (mourning event).
The vertical structure formed based on the results of grouping based on tree height is divided into 4 stratum levels, namely: Based on the level of density per hectare, the highest density data obtained were 86.6 trees/hectare for Gmelina trees, then 80 clumps/hectare for tallang bamboo 80 clumps/ha, then 75 trees/ha, cloves 66.6 trees/ha, cacao 63 .3trees/ha, suren 56 trees/ha, sengon 46.6 trees/ha and coffee 47.5 trees/ha.The density level of bambu Petung, bambu ampel and bambu parring ranges from 2.5-20 clumps/ha.

Table 1 .
The structure and density of plant on agroforestry location in several location 6Sources : Primary data(2019)