Drought-induced anomalies in vegetation condition over wide areas can be observed by using time-series satellite remote sensing data. Previous methods to assess the anomalies may include limitations in considering (1) the seasonality in terms of each vegetation-cover type, (2) cumulative damage during the drought event, and (3) the application to various types of land cover. This study proposed an improved methodology to assess drought impact from the annual vegetation responses, and discussed the result in terms of diverse landscape mosaics in the Mt. Kenya region (0.4° N 35.8° E ~ 1.6° S 38.4° E). From the 30-year annual rainfall records at the six meteorological stations in the study area, we identified 2000 as the drought year and 2001, 2004, and 2007 as the normal precipitation years. The time-series profiles of vegetation condition in the drought and normal precipitation years were obtained from the values of Enhanced Vegetation Index (EVI; Huete et al. 2002), which were acquired from Terra MODIS remote sensing dataset (MOD13Q1) taken every 16 days at the scale of 250-m spatial resolution. The drought impact was determined by integrating the annual differences in EVI profiles between drought and normal conditions, per pixel based on nearly same day of year. As a result, we successfully described the distribution of landscape vulnerability to drought, considering the seasonality of each vegetation-cover type at every MODIS pixel. This result will contribute to the large-scale landscape management of Mt. Kenya region. Future study should improve this method by considering land-use change occurred during the long-term monitoring period.

In recent times, rapid changes in buildings and infrastructural development have increased demand for construction materials. Ndarugu quarries located about 35 km north of Nairobi CBD are among the main sources of building materials in Kenya. The visible evidence of stone mining are the post-quarried sites scarred along the Ndarugu ridge, which has altered the original land condition and continues to affect people who live in surrounding areas. The objectives of the current study were (i) to assess the perception of stone quarry landowners on economic and social impacts of stone quarrying and (ii) to assess status of post-quarry land and factors influencing rehabilitation efforts. Data was collected through interviews guided by questionnaire undertaken along a transect parallel to river Ndarugu ridge where quarrying is concentrated, by sampling alternate homestead and company head. The data collected were analysed using frequencies and association between variables. From the analysis, majority of the respondents (47.1%) were small-scale farmers while 78.8% earned less than KSh. 30,000 (300 USD) per month. Quarrying was in progress in many of quarry sites, while the oldest was quarried 28 years ago. Creation of employment opportunities and opening up of the interior areas for business development were perceived as the main positive impacts of quarrying while influx of new migrants and dust pollution were perceived as the main negative impacts of stone-quarrying. Backfilling with local soil was main environmental repair method identified although a large percentage of the quarried land (95.2%) had not been repaired fully. Crop farming and trees planting were the most preferred post quarry land use. Lack of financial support services and lack of a compulsive legal framework were perceived as main limitations to environmental repair. Matching the quarrying activities with effective landscape management strategies to reduce negative impacts is recommended.

The forest-restoration project of EXPO '70 Commemorative Park, Japan, is an epoch-making attempt to restore a nature-oriented forest park in an urban area in which large-scale land reclamation had occurred. The objective of this paper is to review the concept, planning, and design, and the outcome so far, and discuss current aspects of creating a core natural habitat in the city of Osaka. Innovative planning policy and design methods have been used for construction of the forest-restoration project of EXPO Park.

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Studies were conducted to examine changes in physical and chemical properties of mounded soils applied on the reclaimed site of Expo '70 Park. Sample sites were selected from areas filled with either decomposed granite (Masa) or soils of the Osaka group (OG) and changes in the soil environment accounted for by comparing the soil properties of 10 years to those of 25 years after revegetation at 0-5, 20-25, and 50-55 cm depth levels.Mean hardness of surface soil has increased and that of soils of the OG exceeded Masa soil. Gaseous phase, fine porosity and saturated water permeability (Kg) has increased significantly with corresponding high values for Masa soil than soils of the OG. CEC and exchangeable bases have increased with relatively high values in soils of the OG than in Masa soils. Accretion of total carbon (TC) and nitrogen (TN) contents was observed for both soil types. The average increasing rate of total nitrogen in mineral soils was higher in soils of the OG than in Masa soil. Low C/N ratios observed, indicate significant improvement in the cycling of organic matter. Factors related to the pore structure of the soil influenced changes in the soil environment most, followed by factors related to exchangeable cations. Masa soil was observed to have preferable structural properties, but the OG soils had better nutritive quality. It is suggested that appropriate amendments on the physical structure of the OG soils, may result to faster restoration of the soil productivity and consequently to successful and long-term rehabilitation of devastated sites.