This condition indicated that the number of logging tools used in the company were not yet effective. However, none of the existing data sets have compared the species richness of the different stages of tree regeneration (seedlings, saplings and trees) in relation to farmers' management decisions.
RESULTS AND DISCUSSION A. Results
Diversity of understory in the forest was significantly higher than in RAF (t-test = 10.5; probability 0.01). Number of observed and shaded (estimated) species observed only in forest, only in RAF, in both forest and RAF, and in the combined data set.
DISCUSSION
CONCLUSIONS
Terrestrial pteridophytes as indicators of a forest environment in rubber production systems in the lowlands of Jambi, Sumatra. Repeated seedling-based studies on Shoreaspp., Alstonia Scholis, Acacia crassicarpa and Agathis lorantifolia have shown that many bacteria could promote plant growth at an early stage in the nursery.
INTRODUCTION
In this paper, we present our approaches in the remediation of unfavorable soils using functional bacteria isolated from plant species of Indonesian tropical rainforests. For these purposes, we collected bacteria from different bio-geo-climatically different forests and conducted biological tests to test these bacteria's abilities in improving plant growth. We also discuss our ideas and future studies to further manage these plant-bacteria interactions for bioremediation.
Increasing reports of beneficial effects of functional bacteria on plant growth have inspired many researchers to understand this host-bacterium interaction. The use of plant growth-promoting rhizobacteria (PGPR) to improve seedling growth in forest management nurseries is increasing in subtropical regions (Chanway, 1997; Garcia et al., 2004). Rhizobacteria were collected from different forest conditions and plant species in Indonesia and tested for growth promotion on Acacia crassicarpa, Shorea selanica, Shorea leprosula, Agathis lorantifolia and Alstonia scholaris in the nursery.
MATERIALS AND METHODS A. Isolation and Screening Strategy
Bacteria play a key role in maintaining nutrient cycling, conserving nutrients for plant growth, and improving soil structure and fertility (Lucy et al., 2004). An ordered strategy for studying functional bacteria to promote plant growth generally follows the illustration in Figure 1. An ordered strategy for studying functional bacteria of Indonesian tropical forest plants for biorehabilitation of degraded land.
Exploration and isolation of functional bacteria have been done from biogeoclimatically diverse forest conditions, ranging from abandoned/degraded ecosystems to preserved ecosystems in Indonesia. Ecosystems ranged from unfavorable soils to conserved ecosystems: (1) former coal mines (Figure 2.a and b), cement mines and degraded peat bog forests (Figure 2.c and d) to represented degraded forests and unfavorable lands; (2) nursery to represent a controlled condition; (3) plantation forest of BKPH (Bagian Kesatuan Pemangkuan Hutan or regency-level forest management unit) Gunung Kencana to represent a monoculture/. Regular strategy in the investigation of functional bacteria of Indonesian tropical forest plants for biorehabilitation of degraded soils.
RESULTS AND DISCUSSION
Bacterial identification showed that gram-negative bacteria isolated mainly from host plants indicate the general nature of the plant rhizosphere (Table 1). Predominance of gram-negative bacteria in the rhizosphere was previously reported by Olsson and Persson (1999) and Donata-Correa et al. 2004) who investigated rhizosphere bacteria of tagasth and barley plants. This study by Sitepu et al.(2003) enabled selection of the most prominent rhizobia for the acceleration of A. crassicarpa growth which is significant from economic and ecological points of view for nursery management. Dipterocarp seedlings responded variably to bacterial inoculation and most of the inoculated seedlings showed growth promotion.
Therefore, research on the local biopotential of rhizobia from each of the target sites for bioremediation should be included. Seedlings inoculated with PGPR (including rhizobia) or consortium inoculants would lead to increased survival rates after transplanting. In the process of adopting seedlings in unfavorable environments in a complex and natural situation, the most important and interesting nature of PGPR-plant interaction can be revealed.
POOLS AND TURNOVER- RATES OF THE GLOBAL CARBON CYCLE
The major pools and turnover rates of the global carbon (C) cycles are presented and compared with the human production of CO2 from the burning of fossil fuels (e.g. coal and oil) and geothermal fuels (natural gases), both categorized as non-renewable energy resources that reach in quantity about 6.5 Gigaton C per year. The focus of understanding the molecular biology of the legume-rhizobia symbiosis as a major contributor to nitrogen fixation is in the areas of signal exchange between host plants and rhizobia in the rhizosphere, including the kink factor signal, the infection and nodule compartmentalization and the grounds. stress factors that affect the symbiosis. First, we need more information about the so-called missing sink, since the carbon dioxide concentration in the air does not reflect the current data on the carbon pools and turnover rates.
However, a major limitation of these data is the very limited number of stations that are located more for historical reasons than for geographical reasons on islands scattered in the world's oceans. Deforestation and land clearing in developing countries alone contribute about 1.6 G t C annually, about a quarter of global carbon dioxide emissions (Murdiyarso, 2007). THE NITROGEN CYCLE: LEGUME NITROGEN FIXATION More than 60% of the world's production of legumes is taken up by.
When we look at the geographic areas from the South Pole to the equator and on to the North Pole including land and oceans, we observe two large zones where CO2 sinks at 30 oS and 60 oN, whereas areas around the equator are large CO2 sources (Enting and Mansbridge, 1991). Only Psophocarpus tetragonolobus with 33% protein, Glycine max with approx. 34% and Lupinus mutabilis with 48% is significantly above this range. Three genera with a protein content above 25% have high lipid concentrations with 16% in Psophocarpus tetragonolobus, 18% in Glycine max and up to 48% in Arachis hypogaea (peanuts) (Werner, 2005).
SOIL STRESS FACTORS AFFECTING THE SYMBIOSIS
Phosphorus concentration in fi x+ nodules is about 60 % higher than in root tissues, but the same as in fi x nodules (Kuhlmann et al., 1982). In addition to nutrient acquisition, the AM-fungal symbiosis also protects host plants against drought stress (Ruiz-Lozano et al., 2001) and also salt stress (Augé, 2001). Also PGPR (Plant Growth Promoting Rhizobacteria) can help AM fungi in phosphate solubilization for host plants (Bareaet al., 2002a; Barea et al., 2002b).
Bacteria are stable cytoplasmic components that are transmitted through vegetative spore generations (Bianciotto et al., 2004) and are considered obligate endosymbionts (Bonfante, 2005). The sensor/regulator pair ActS/ActR has been studied in most detail in Sinorhizobium meliloti (Glenn et al., 1999). The leucine biosynthesis mutant was able to survive at pH 3.5, where the wild-type strain could not (Steele et al., 2003).
THE LEGUME-RHIZOBIA SYMBIOSIS AS BIOTEST SYSTEMS FOR SOIL CONTAMINANTS
EC50 for nodulation, shoot growth and root growth in the Medicago sativa/Sinorhizobium meliloti system. A factor of 10 higher sensitivity represents a very significant progress in evaluating the potential risk in the food chain, from soil to plants and to humans and animals. In the legume Glycyrrhiza uralensis, a 10 to 100-fold increase in β-radionuclides has been found in the plant ash of above-ground material compared to the soil.
The aim of the study was to find out an efficient number of tools used for logging in a timber estate. 41 units of chainsaws for felling, 42 units of skid farm tractors, 9 units of loaders for loading and unloading, and 36 units of trucks for transportation; (2) The number of recording instruments as obtained from all activities in the field was less than that of the analysis based on production target and realization. This condition indicated that the number of logging tools used in the company were not yet effective.
MATERIALS AND METHODS A. Location
Using a greater number of tools can technically guarantee high wood production, but may not be economically acceptable. In relevance, the aim of this research was to find out an efficient number of logging tools used in a timber plantation, based on the company's production target and production realization. Labor productivity per day x working time per year where: NCT = number of chainsaws based on production target. units);.
NCR = number of chainsaws according to production realization (units); PT = production target (m3/year); and PR = realization of production (m3/year). The number of mechanical tools required (sliding, loading and unloading and transport tools) (Keputusan Menteri Kehutanan No. 12 months x working day per month x journey per day x TC where: NT = number of mechanical tools based on production.
RESULTS AND DISCUSSION A. Working Productivity
In short, the use of fewer logging tools in the field resulted in less timber production. This situation was caused by less available wooden tools (17 units) compared to those based on production target and production realization, i.e. Efficient operation of the Forest Company was dependent on the number of logging tools based on timber production objective, i.e.
The actual number of logging tools operating in the field is less than it should be based on the analysis of target log production and production realization. This situation showed that the operation and available number of logging tools in the field is not yet efficient. Actual machine costs for field logging tools are lower than those based on target log production and log production realization.
MATERIALS AND METHODS
Intensity of marine borer infestation in untreated wood species after three months (A) and six months (B) of exposure to the sea. The difference in polymer loading in each wood species was influenced by its wood structure. The difference in the resistance capacity of the wood to the attacked pit is due to the differences in the natural properties of the wood species. Intensity of marine borer infestation on wood-plastic composites after three months (A) and six months (B) exposure at sea.
This experiment also revealed that all plastic wood was attacked by the marine borer family of Pholadidae. Wilkinson (1979) stated that all woody species in waters that have a high Pholadidae population will be attacked by this marine borer. Intensity of marine borer infestation on CCB-treated wood (A) and untreated wood (B) after twelve months of exposure in the sea.
CONCLUSION
