Non-point source pollution, such as nutrient runoff to waterways from agricultural production, is an environmental problem that typically involves asymmetric information. Land use changes to reduce pollution incur opportunity costs that are privately known to landholders, but these changes provide environmental benefits that may be more accurately estimated by regulators. This paper reports a testbed laboratory experiment in which landholder/sellers in multi-round, sealed-offer auctions compete to obtain part of a fixed budget allocated by the regulator to subsidize pollution abatement.

Conversion of arable land (maize) to pasture will affect the soil organic matter (SOM) content. Changes in the SOM content were studied using a size- and density-fractionation method and C-13 analysis. Twenty-six years of maize cropping had resulted in a depletion of carbon stored in the macro-organic fractions (>150 mu m) and an increase in the 250 mu m), light (b.d. 150 mu m) and light (b.d. 150 mu m; b.d. >1.13 g cm(-3)) in the 0- to 20-cm layer was still 40-50% lower than in the continuous pasture plots.

Climate change issues are contemporary global phenomena which affect the largest part of the world in different ways. This paper explores how local communities living in sensitive ecological areas, particularly in river valleys, respond to and adapt to climate change. By employing a qualitative research approach, findings have indicated that heavy rainfall and prolonged droughts coupled with population increase have led to land use changes and loss of biodiversity in the river valley.

 Most of the cities and urban centres of developing nations, Tanzania inclusive are faced with increased urbanization coupled with informal land development in non-designated areas including marginal and hazardous lands. This paper reports the findings of a study undertaken to assess the processes of land development and the associated impacts in Msasani Bonde la Mpunga, a, flood prone area in the City of Dar es Salaam.

La région Tanger-Tetouan-Al Hoceima située au nord-ouest du Maroc a connu, dans des dernières décennies, différents travaux d’aménagement de territoire qui ont eu, certainement, un impact sur le paysage et l’écosystème de la région. La région a accueilli des infrastructures de grandes tailles telles que le port Tanger Med installé au bord du détroit Gibraltar, la ligne de train à grande vitesse reliant Tanger à Casablanca, réseaux routiers, barrages…etc. L’objectif de cet article est de cartographier les changements du paysage de la région via l’analyse diachronique de l’occupation du sol.