HTT29-P01

Room:Convention Hall

Time:May 24 18:15-19:30

Preliminary study on detection limits of abandoned farmlands using NDVI and NDWI
time-series data
SAKUMA, Asahi1∗ ; SHIMAZAKI, Hiroto1
1

National Institute of Technology, Kisarazu College

Increase of abandoned farmlands is gaining attention in Japan as a problem causing difficulties such as: expansion of breeding
habitat potentially preferred by vermin; increase of small parcels where illegal dumping occurs; and deterioration of rural landscapes. To address this problem, it is important to periodically survey the extent and distribution of abandoned farmlands overa broad spatial range. However, conventional surveying methods are labor intensive and time-consuming, requiring surveyors tocover every parcel often situated in hostile locations.
Remote sensing provides us with a low cost, repeatable alternative means for broad-scale mapping of abandoned farmlands.
A previous study suggested that Normalized Difference Vegetation Index (NDVI) derived from remotely-sensed data could havepotential to discriminate an abandoned paddy from a paddy area since the difference in NDVI becomes significant at the periodsof one month after planting and two months after harvesting. Normalized Difference Water Index (NDWI) was also applied
successfully to detecting changes in agricultural activity in a paddy area. However, the success of previous studies depends on
acquiring data not affected by cloud contamination at the suitable timing in terms of crop calendar.
The objective of this study is to assess the detection limit of an abandoned paddy using the time-series data derived fromMODIS surface-reflectance products. Firstly we refined the time-series reflectance data by removing the effects of cloud contamination based on the Savitzky-Golay filter. Secondly a simple linear mixture model was adopted to estimate temporal signaturesof underlying end-member landcover types and simulate mixed signatures at different end-member compositions. Thirdly wecalculated NDVI and NDWI time series using the simulated signatures and explored the minimum fraction of abandoned paddy
potentially including the signal relevant to cessation of agricultural activity. Preliminary results showed that successful detection
is limited to the pixel dominated by abandoned paddy areas.
Keywords: abandoned farmland, spatial resolution, temporal resolution, time-series analysis, mixed pixel

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HTT29-P02

Room:Convention HallTime:May 24 18:15-19:30

Evaluation of land cover classification methods targeting unmanaged farmland
MISHIMA, Yoshio1∗ ; FUKASAWA, Keita1 ; YOSHIOKA, Akira1 ; KUMADA, Nao1 ; OGUMA, Hiroyuki1 ;YAMANO, Hiroya11

National Institute for Environmental Studies

In order to reveal the impact of evacuation on biota, National Institute for Environmental Studies is monitoring biota in areas
evacuated as a result of nuclear disaster, and the surrounding areas in Fukushima Prefecture, Japan. It includes the monitoringof ”land cover” in the study area. This involves regular observation of areas that contain ”residential area” and ”arable land”,
where humans have historically performed regular maintenance. These are fundamental elements to discuss the change of local
ecosystems due to abandonment. Areas of arable land in the study area are much greater than the residential areas. For thisreason, priority should be given to the analysis of arable land. Environmental change in unattended farmland associated withevacuation is relatively quick. And the physical environment of arable land typified by moisture condition is different for eachpaddy and upland field plot. Therefore, it is necessary to monitor field plots with distinguishable spatial resolution in shortcycles. This study evaluated land cover classification methods for arable land considering these requirements. Spaceborne
satellite imagery was used with revisit time and spatial resolution matched to these conditions. Arable land in the study area wasfirst defined by aerial photo interpretation. Then, using multi-temporal, multispectral imagery (RapidEye, spatial resolution =5 m) and single polarization of L-band SAR imagery (PALSAR-2, spatial resolution = 3 m), land cover was categorized basedon the machine learning classification methods with training data. Comparison of multiple methods and datasets revealed aclassification technique that combines SAR data and multispectral imagery provided improved classification accuracy.
Keywords: unmanaged farmland, land cover, remote sensing, machine learning, SAR

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HTT29-P03

Room:Convention Hall

Time:May 24 18:15-19:30

Monitoring and Analysis of Land use/cover change in Kashigar region Based on Landsat
and Spot vegetation Data
MAIMAITIAILI, Ayisulitan1∗ ; AJI, Xiaokaiti2 ; KONDOH, Akihiko2
1

Chiba Univ., 2 CEReS, Chiba Univ.

The spatio-temporal changes of land use / cover (LUCC)and its driving forces in Kashigar region, Xinjiang Province wereanalysed by satellite remote singing data. Main goal of this paper was to quantify drivers of LUCC using long term Landsat
and Spot Vegetation data from 1972 to 2014. First ,we produced LUCC map by using Landsat images in 1972,1990,2000and2014. Land use information from Landsat data was collected using maximum likelihood classification method.A hierarchicalclassification system of 16 land cover subclasses was applied to the Landsat data.The 16 subclasses of land cover were further
grouped into 6 aggregated classes of land cover: urban,cropland, water,grass,bare land and glacier.Land use change was studied
based on the change detection method of land use types.Second, Normalised Difference Snow Index(NDSI) values was calculatedby Spot Vegetation data from 1999 to 2014. According to the snow index confirmed snow conditions of study area which is used
to screen the LUCC and climate changes after snow cover map drawn.Third, driving forces were analysed according to climatechanges and socioeconomic development.The climate data was obtained from CRU TS 3.21 about temperature and precipitation
data. According to these data climate changes were compared with NDSI value,while the socioeconomic data was from theXinjiang Statistical Yearbook(1984-2014). The study indicates that the increase of land use benefits was given more attention.Thestudy suggests that the land use should be based on the sustainable protection of arid environment on the Kashigar region.
Keywords: Land use /cover change, driving force, snow index, Kashigar region

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HTT29-P04

Room:Convention HallTime:May 24 18:15-19:30

The Relationship between the Food production and Water Resources of Xinjiang Provence
XIAOKAITI, Aji1∗ ; AYSULITAN, Maimaitili2 ; KONDOH, Akihiko3
1

Center for Environmental Remote Sensing, Chiba University, 2 CopyrightFaculty of Science, Chiba University, 3 Center for Environmental Remote Sensing, Chiba University
In this study, To identify the relevance of snow cover and food production which is the main snow-ice malted water resources
for an arid and semi-arid region of Xinjiang province, by Spot Vegetation data(1999-2012years).First,calculated Normalised
Difference Snow Index(NDSI) by Spot Vegetation data. Second, according to the NDSI value snow cover map of study areadrown. Third, examined and analyzed spatiotemporal changes of snow cover area of study area. In addition from the Xinjiang
statistical yearbook extracted cultivated land area and effective irrigation area data further digitized by GIS making map andanalyzed spatial variations of food production stouts in Xinjiang province.
The result of the spatiotemporal changes of snow cover area was that the snow caver area is increased from 9636.5000km to13957.2000km from 1999 to 2012. it has been increasing approximately by 4320.5000km in the recent 14 years.Remarkableincreasing has happened that the snow cover area at
Kulun mountains side of North Xinjiang. Tianshan Mountain‘s snow cover areas also has increased but shows fluctuatedtrend.It was confirmed that Xinjiang statistic yearbook shows that cultivated land area and effective irrigation areas are increasedsame results that snow cover area are increased especially in fan-like area around at Kunlun Moutian side of North Xinjiang.

Keywords: Xinjiang uyghur autonomous region, Food production, Snow area, Water, SPOT/VEGETATION, NDSI

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