Abstract: Following the implementation of the Green for Grain Project in 2000 in Guyuan, China, the decrease in cultivated land and subsequent increase in forest and grassland pose substantial challenges for the supply of biological products. Whether the current biologically productive land-use patterns in Guyuan satisfy the biological product requirements for local people is an urgent problem. In this study, the ecological footprints of biological resource consumption in Guyuan were calculated and analyzed based on the ‘City Hectare’ Ecological Footprint (EF) Method. The EFs of different types of biological resource products consumed from different types of biologically productive land were then analyzed. In addition, the EFs of various biological resource products before and after the implementation of the Green for Grain Project (1998 and 2012) were assessed. The actual EF and bio-capacity (BC) were compared, and differences in the EF and BC for different types of biologically productive lands before and after the project were analyzed. The results showed that the EF of Guyuan’s biological resource products was 0.65866 ha/cap, with an EF outflow and EF inflow of 0.2280 ha/cap and 0.0951 ha/cap, respectively. The per capita EF of Guyuan significantly decreased after the project, as did the ecological deficit. Whereas the cultivated land showed a deficit, grasslands were characterized by ecological surplus. The total EF of living resource consumption in Guyuan was 810,941 ha, and the total BC was 768,065 ha. In additional to current biological production areas, approximately 42,876 ha will be needed to satisfy the demands of Guyuan’s people. Cultivated land is the main type of biologically productive land that is needed.
Abstract: The Soil and Water Assessment Tool (SWAT) is a watershed-based, semi-distributed hydrologic model for simulating hydrological processes at different spatial scales. The SWAT hydrology and erosion/sediment components are first validated after the hydrologic components calibration. The SWAT model also utilizes geographic information system (GIS) and digital elevation model (DEM) to delineate watersheds and extract the stream network. This study applies SWAT model to assess the impacts of land use change on soil and water losses from Yang Ming Shan National Park Watershed in northern Taiwan. Although the government has formulated regulations to limit the development, however, intense human activities, such as farming and building construction, still continue to exist. This study utilized two land-use data periods, one in 1996 and another in 2007, along with the SWAT model to simulate soil and water losses in Yang Ming Shan National Park. Based on the baseline scenario, the SWAT model was also successful in simulating the future scenario. Study results for scenario 2007, as compared to 1996 baseline period indicate that land use change shows forest land decreases about 6.9%, agricultural land increases about 9.5%, and causes sediment yield increase of 0.25 t/ha. Human activities deserve more attention when assessing soil and water losses because of their inevitable impacts. Government needs to modify land development policies and plans for land use change detection using satellite imagery to avoid illegal development activities.
Abstract: Conversion of rangelands into cultivated land is one of the main challenges affecting the management of rangelands in Ethiopia. In order to inform policy makers about trends in land-use conversion, this study examined the drivers, trends, and impacts of land conversions in five locations selected in the Borana rangelands of Southern Ethiopia. This study integrated survey interviews from agro-pastoralists, participatory appraisals, rainfall data, and remotely sensed satellite data from Landsat images taken in 1985 and 2011. Results indicate that there is a marked increase in cultivated land in some of the study sites while in the other sites there is a slight reduction. The bare lands increased in some parts of the study sites though there was slight recovery of grassland in some of the degraded areas. Settlement areas with permanent housing increased. Woodland vegetation decreased except on mountain escarpments where there were slight gains. The results further show that, during this period, bushland decreased while at the same time grassland increased. Shrub/grassland with seasonally flooded areas increased in the bottomlands. Inhabitants interviewed in the study areas perceived land use and land cover changes to be driven by interplay of recurrent drought, loss of pasture, food insecurity, and decline in income. Changes in policies that govern natural resources have influence the land use change in this area and the expansion of cultivation. Expansion of cultivation practices upon rangelands has resulting in significant loss of vegetation biomass and soil erosion, thereby precipitating rangeland degradation. The results provide comprehensive insights regarding the influence of internal and external drivers of land conversion that should be considered when making decisions for land use planning.
Abstract: This paper reports a contingent valuation study on household kitchen waste separation (HKWS) services via willingness to pay (WTP) conducted in the Haidian and Dongcheng districts of Beijing city in 2013. This study focuses on a real program to understand households’ attitudes toward HKWS and to estimate the value of HKWS services. The results of this study revealed that 41.4% agreed to accept the proposed price of HKWS services, while 42.2% refused to pay, but with a positive attitude toward the HKWS program. In addition, respondents’ WTP for proposed HKWS services is significantly related to the level of bid price and their gender, age and education experience. Attitudinal factors that affect resident WTP were also found. For example, respondents who perceive themselves as having a higher ability to conduct HKWS at the source are more willing to pay for their HKWS services, while respondents who complain of the inconvenience of conducting HKWS show negative WTP. The results also showed that on average each household is willing to pay about US$1.44 per month for HKWS services, which is based on 327 respondents after excluding 64 (16.4% of all sample) who indicated complete opposition to the HKWS program.
Abstract: Historical aerial images are important to retain past ground surface information. The land-use land-cover change in the past can be identified using historical aerial images. Automatic historical image registration and stitching is essential because the historical image pose information was usually lost. In this study, the Scale Invariant Feature Transform (SIFT) algorithm was used for feature extraction. Subsequently, the present study used the automatic affine transformation algorithm for historical image registration, based on SIFT features and control points. This study automatically determined image affine parameters and simultaneously transformed from an image coordinate system to a ground coordinate system. After historical aerial image registration, the land-use land-cover change was analyzed between two different years (1947 and 1975) at the Tseng Wen River estuary. Results show that sandbars and water zones were transformed into a large number of fish ponds between 1947 and 1975.