For the purpose of obtaining information about recent changes of distribution of paddy field in the Heilongjiang Province of China, a method to estimate the area of paddy field in spatially wide range using MODIS data was developed. Land cover condition of the site exhibit characteristically as the mixture with paddy field inundated by water and upland field exposed by bare soil as well as vegetation of perennial trees during the first of June, when rice was transplanted just before the period for the whole part of Province. Based on this feature, two indices derived from MODIS data, NDVI (Normalized Difference Vegetation Index) calculated by using the reflectance of Band 1 and Band 2 and NDBSI (Normalized Difference Bare Soil Index) by Band 1 and Band 7, were introduced. The allocation in the two dimensional scattergram of NDVI and NDBSI showed evidential relation with the fractional area of paddy field per pixel, thereafter, the relation was formulated by introducing integrated indicator obtained from the scattergram. The estimated acreage showed high correlation with the area obtained from Landsat data in condition that the amount was assembled by administrative unit of County. The scattergram produced for different years exhibited the similar features, therefore, the same scheme could be adopted to estimate for continuous years. The method mentioned above estimated the distribution of paddy field in the Heilongjiang Province for the period from 2003 to 2007. The results successfully indicated the substantial increase of area of paddy field in the Sanjiang Plain located in the eastern part of the Province for 2006 and 2007, which could supplement the lack of statistical information.
This study aimed to estimate onion area based on the spectral characteristics using satellite data. SPOT data were obtained from middle June to middle August in Hokkaido at growth season of onion. The reflectance of the red and near infrared in onion fields was higher than those in other crops, because onion leaves fall down and covered soil surface just before harvesting in late July. Therefore, using the above characteristics, onion classification map was generated by maximum likelihood method of supervised classification. As results, the onion area was underestimated with 15.2% error. The factor of the underestimated area was considered to be missed classification in the areas of boundary of the field. To reduce the error, polygon data for each field in surveyed area were superimposed on the obtained onion classification map and the total field area with predominantly onion was calculated. As a result, the estimated area has high accuracy with 97.8%.From above results, it was clarified that onion area could estimated with high accuracy by combing SPOT data with topographic field data.
In order to comprehend the characteristics of the abandoned bamboo stands, the allometry formula and the aboveground biomass of P. pubescens, P. bambusoides and P. nigra were determined and subsequently the structure of abandoned bamboo stands were investigated. We revealed that the allometric correlations between the diameter at breast height (DBH) with dry weight of stem, branch and leaf of these species. There were close relationships between DBH and the dry weight of stem, based on the field verification. However, there were not so close relationships between DBH and dry weight of branch and leaf. The aboveground biomass was calculated using these allometric correlations to correlate DBH and dry weight of stem, branch and leaf. The structure of the abandoned bamboo stands was uniformed if compared to the managed bamboo stands, where the characteristics of aboveground biomass, standing density and ratio of dead bamboo varied at the investigated bamboo stands. The standing density of the abandoned bamboo stands was larger than that of the managed bamboo stands. However, the aboveground biomass of the abandoned bamboo stands was lower than that of the managed bamboo stands. On the abandoned bamboo stands which dominated by P. pubescens, the increase of degree of ruin caused the increase of aboveground biomass. It likewise was observed on the abandoned bamboo stands which dominated by P.bambusoides, the raising of degree of ruin lead to the raising of standing density.
We estimated the potential amount of energy crops that were able to be produced without competing with food and decreasing forest area in Indonesia. The per capita rice consumption rate in each country of Southeast Asia has started to decrease along with becoming westernized in dietary habits, while rice yields continue to increase steadily. It is forecasted that Southeast Asia will have a surplus paddy field area. This surplus area could be used to produce energy crops without decreasing the forest area in the countries. The economic gaps among regions become aggravated at the same time, and a remarkable difference appears to the consumption of food by the living standard though the per capita rice consumption recently reached saturation in Indonesia. Thus the possibility of the energy crops production was examined based on considering the style of food consumption according to the expenditure classes. The per capita consumption of rice and animal products consumption in 2030 is predicted to be 0.9 times and 1.8 times respectively compared with present in Indonesia. The total surplus area is predicated to be 530,000ha in 2030, and 45.98 million tons of sugarcane could be produced from that area. The energy from this sugarcane would be 3.8% for the gasoline consumption of Japan.
Massive expansion of abandoned bamboo stands has been observed recently in various parts of Japan, and the original forests change to bamboo stands. In order to comprehend the transition of the carbon storage of forest ecosystem, when the abandoned bamboo stands invade surrounding forests, the biomass and carbon storage of three abandoned bamboo stands in Gifu Prefecture were estimated. In the results of this research, the aboveground biomass of abandoned bamboo stands was from 35.1t/ha to 69.2t/ha for curms and from 7.0t/ha to 17.4t/ha for leaves and branches. The total aboveground biomass was from 42.1t/ha to 83.5t/ha, within the range of the results of existing research. The litterfall biomass was 4.68t/ha and 5.75t/ha. The belowground biomass was from 10.4t/ha to 25.7t/ha for stumps, from 26.0t/ha to 34.5t/ha for rhizomes and from 40.2t/ha to 53.4t/ha for fine roots. The total belowground biomass was from 89.1t/ha to 98.5t/ha, that was larger than that of existing research. The carbon content rate of Phyllostachys pubescens was 48.9% for curms, 48.2% for branches, 45.2% for leaves, 45.6% for rhizomes and 44.8% for fine roots. The carbon storage of soil in abandoned bamboo stands was from 54.9t/ha to 113.8t/ha. Total carbon storage of abandoned bamboo stands ecosystem except soil carbon storage was less than that of the other vegetation forest ecosystem. When the abandoned bamboo stands invade surrounding forest, the carbon storage of new forming bamboo stands might become below the half compared with that of original forests.
On-site remote sensing technology associated with the use of digital camera is becoming a promising tool for precision agriculture such as for crop growth management and monitoring damage by insects and diseases. We developed a vegetation sensor using general-purposed digital camera. In this study, a paddy field in Oita Pref. was chosen as the study site. We have examined relations between the SPAD and NDVI (Normalized Difference Vegetation Index) and between the protein content and NDVI for both maximum tiller number stage and dough-ripe stage. For the maximum tiller number stage, a positive correlation of the SPAD and NDVI was found (as R2=0.96). Similarly there was a positive correlation between the protein content and NDVI (as R2=0.88) in the dough-ripe stage. The study results proved the applicability of on-site remote sensing technology associated with the use of digital camera for the growth diagnosis and protein content estimation of paddy rice.
An interactive program was developed to predict developmental stage of plants using nonparametric DVR(DeVelopmental Rate) method. R（version 2.41） was employed as a programming language. Considerable ingenuity allows an interactive program, while R is not geared to develop interactive programs. This program realizes one-dimensional DVR method, twodimensional DVR method, thin plate spline DVR method by simple procedures.