Aim
This theme aims to use information of vegetation (greenness) derived from satellite observations (hereafter referred to as “vegetation index”) to integrate the spatiotemporal characteristics of vegetation change in Asia with meteorological data, and to perform analyses. To create a map database, while shedding light on the correlation between the change in vegetation and weather from a macro perspective, we also incorporated agricultural data to show the correlation with agriculture. The following five items were established as the concrete plans for fiscal year 2006: (1) Highlight the relationship between the interannual change in agricultural insurance payouts and vegetation index for paddy rice throughout Japan; (2) Investigate the relationship between the interannual change in the vegetation index and air temperature, precipitation, and photosynthetically active radiation (PAR) on a global scale; (3) Explore the links between the quantity of damaged paddy rice harvest with respect to low temperature damage and conditions such as rice paddy acreage; (4) Prepare Chinese agricultural data; and (5) Proceed with the building of ecosystem datasets related to this research theme.
TOP > Research Tasks > Land Ecosystem
Land Ecosystem
Building a Database on the Land Ecosystem Linking System in Asia
Findings
The findings of the above items (1) though (5) are given below.
(1) We built a database containing daily vegetation index data for all of Japan, and produced animations of the map. The TWO algorithm developed by a group at Chiba University was applied to reduce the impact of cloud contamination. Based on this dataset, we investigated the relationship between the average nationwide vegetation index and agricultural insurance payouts with the interannual change in air temperature (Figure 1). On the basis of these results, we established an empirical prediction model.
(2) We mapped the correlation coefficients of interannual changes between the vegetation index and air temperature, precipitation and PAR over a 10-year period between 1986 and 1995 (Figure 2). As a result, we found a strong positive correlation between the vegetation index and air temperature in the northern hemisphere in regions at northern latitudes of 60 degrees and higher. In most other regions, there was a significant positive correlation coefficient between the vegetation index and precipitation. We found that regions with a strong correlation to PAR were scattered, and roughly corresponded to those areas with high cloudiness such as the savannah region of South Africa, southeastern China and Siberia (Suzuki, 2007).
(3) We analyzed the interannual change in the relationship between the economic loss of paddy rice damage and air temperature in the towns of Shigeki-cho and Ichikai-machi in Tochigi Prefecture. We found that there were settlements that were insensitive to low temperatures and suffered little damage, as well as those that were sensitive and suffered significant damage. In general, we found that settlements with a high proportion of full-time farmers and large acreage suffered less damage. Using these results, we created a map (Figure 3) to evaluate the per-settlement decrease in yield from low temperature damage (in order words, resistance to low temperature damage) due to agricultural economic conditions with respect to paddy rice.
(4) From Chinese Agricultural Statistics, we undertook the digitization of statistically significant items spanning 1987 to 2000. We also visited research institutes and publishers in Beijing to collect materials on agriculture.
(5) We produced a list of various data on land and ocean ecosystems to be created in the future.
The findings of the above items (1) though (5) are given below.
(1) We built a database containing daily vegetation index data for all of Japan, and produced animations of the map. The TWO algorithm developed by a group at Chiba University was applied to reduce the impact of cloud contamination. Based on this dataset, we investigated the relationship between the average nationwide vegetation index and agricultural insurance payouts with the interannual change in air temperature (Figure 1). On the basis of these results, we established an empirical prediction model.
(2) We mapped the correlation coefficients of interannual changes between the vegetation index and air temperature, precipitation and PAR over a 10-year period between 1986 and 1995 (Figure 2). As a result, we found a strong positive correlation between the vegetation index and air temperature in the northern hemisphere in regions at northern latitudes of 60 degrees and higher. In most other regions, there was a significant positive correlation coefficient between the vegetation index and precipitation. We found that regions with a strong correlation to PAR were scattered, and roughly corresponded to those areas with high cloudiness such as the savannah region of South Africa, southeastern China and Siberia (Suzuki, 2007).
(3) We analyzed the interannual change in the relationship between the economic loss of paddy rice damage and air temperature in the towns of Shigeki-cho and Ichikai-machi in Tochigi Prefecture. We found that there were settlements that were insensitive to low temperatures and suffered little damage, as well as those that were sensitive and suffered significant damage. In general, we found that settlements with a high proportion of full-time farmers and large acreage suffered less damage. Using these results, we created a map (Figure 3) to evaluate the per-settlement decrease in yield from low temperature damage (in order words, resistance to low temperature damage) due to agricultural economic conditions with respect to paddy rice.
(4) From Chinese Agricultural Statistics, we undertook the digitization of statistically significant items spanning 1987 to 2000. We also visited research institutes and publishers in Beijing to collect materials on agriculture.
(5) We produced a list of various data on land and ocean ecosystems to be created in the future.
Figure 1: The relationship between insurance payouts on paddy rice (blue) and the nationwide average vegetation index in August (green). Average air temperatures in Japan (red) were shown for reference purposes.
Figure 2: The strength of the correlation of interannual changes between vegetation index (NDVI) and air temperature (T), precipitation (P) and PAR. Magenta, cyan and yellow each show the strength of the relationship of interannual changes from 1986 to 1995 between satellite-derived vegetation and air temperature, precipitation and PAR.
Figure 3: Per-settlement decrease in yield from low temperature damage (i.e. the resistance to low temperature damage) due to agricultural economic conditions. Although the quantity damaged is largely dependent on climatic conditions, the decreased yield due to damage differs based on agricultural economic conditions at settlements such as the percentage of acreage devoted to rice paddies and the proportion of the old-aged workforce.
Reference Literature
1) Rikie Suzuki: "Preliminary analysis on interannual response of global NDVI for precipitation, temperature, and radiation", Proceedings of the Seventh International Conference on Global Change: Connection to the Arctic (GCCA-7), 293-296, (2007)
Reference Literature
1) Rikie Suzuki: "Preliminary analysis on interannual response of global NDVI for precipitation, temperature, and radiation", Proceedings of the Seventh International Conference on Global Change: Connection to the Arctic (GCCA-7), 293-296, (2007)
