Establishment of Inventory on Carbon and Nutrient Cycling in Tropical Peatland Ecosystems for Sustainable Agro-production and Environmental Conservation

热带泥炭地对全球陆地表面净碳(C)储量具有重要意义，但它也被认为是CH4的主要排放源。土地资源的开采和泥炭的燃烧增加了泥炭地的碳释放，从而加剧了全球变暖。为了确定热带泥炭地的农业和火灾对全球变暖的影响程度，在2001年至2003年期间，测量了包括森林和农田在内的各种生态系统以及普兰卡拉亚附近Karampangan地区受火灾影响的土地的地表三种主要温室气体（CO2， CH4和N2O）的排放。森林燃烧后，天然林的全球升温潜能值下降了32-42%，其中99%的全球升温潜能值来自二氧化碳排放。然而，没有树木可以吸收二氧化碳，所以二氧化碳直接排放到大气中。燃烧后的泥炭地排放了CH4，而天然林和再生林都吸收了CH4。农田的全球变暖潜能值约为天然林的2倍。农业领域的二氧化碳排放量约为日本农作物领域的5倍，占全球变暖潜能值的50-90%。其余的全球变暖潜能值由N2O排放贡献。N2O排放量相当高，占626 kg N / ha1年-1氮肥施用量的4-23%。这可能是由于农田的高pH和高交换性钙含量促进了泥炭的高分解和高硝化作用。森林火灾对全球变暖的影响程度远高于农业。农田施氮可加速豌豆分解，增加N2O排放，降低CH4吸收。

Tropical peatland is important for net carbon (C) storage in the global land surface, but it is also believed to be a major emission source of CH4.Land resource exploitation and burning of peat increases C release from the peatland, and thus contributes to overall global warming. In order in discern the magnitude of agricultural and fire impacts in tropical peatlands on global warming, ground surface emissions of three major greenhouse gases (GHG), CO2, CH4 and N2O, were measured in various ecosystems including forests and agricultural fields, as well as fire-affected lands in Karampangan zone, near Plangka Raya, from 2001 to 2003.After forest burning, the GWP decreased in 32-42% of the GWP from the natural forest, with 99% of the GWP occurring from CO2 emission. However, no trees could absorb the CO2, so the CO2 emissions went directly to the atmosphere.CH4 was emitted from the burned peatland, while CH4 uptake was observed in both the natural and regenerated forests.The GWP in the agricultural field was approximately 2 times larger than that from the natural forest. CO2 emission in the agricultural field was about 5 times larger than that in Japanese crop fields and accounted for 50-90% of the GWP. The remaining GWP was contributed by N2O emission. The N2O emission was considerably high, accounting for 4-23% of the nitrogen (N) application rate of 626 kg N ha1 yr-1.This is probably due to high peat decomposition and high nitrification enhanced by high pH and high exchangeable Ca content us the agricultural fields.Magnitude of forest fire impact on global warming was much higher than agricultural impact. But nitrogen application in agricultural field, which may accelerate peas decomposition, enhanced N2O emission and deduced CH4 uptake.