Sustainable natural resource management in regional ecosystems : case studies in semi-arid and humid regions

Abstract

Sustainability calls for policies that meet current societal needs without compromising the needs of future generations; thus, a dual relationship between human and natural resources is required. The main goal of the current research was to introduce up-to-date environmental techniques for sustainable natural resource utilization in semiarid and humid ecosystems in short and long term. To achieve this goal, two studies were implemented. First, sustainable land use management was evaluated in a newly reclaimed, semiarid region in the Bustan 3 area (341.27 km2), Egypt. To achieve sustainable management in this agro-ecosystem; detection of land cover change, assessment of the most sensitive areas to desertification, and evaluation of land capability for agricultural use were required. Using multi-temporal remotely-sensed data in the Bustan 3, the results indicated that this area had been drastically changed from 100% barren desert land to 79% agricultural land, due to successful land reclamation efforts in the 1990s. Although 70% of this area had a good capability for agricultural production, ¡­89% of the Bustan 3 area was critically sensitive to desertification. By applying suitable land management scenarios, the land capability for agricultural use could be increased. Second, a natural resource conservation program was examined by studying the effects of compost/mulch, as a best management practice, for soil erosion control on highway roadsides in Louisiana, USA (a humid region). Louisiana is plagued by widespread impairments to surface water quality. Total suspended solids (TSS) and associated turbidity in runoff water are considered the most problematic nonpoint source pollutant of Louisiana surface waters. At the plot scale, the effects of compost/mulch on soil and water resources were evaluated. Research results showed that the use of compost/mulch without tillage incorporation successfully conserved the topsoil on the roadsides, increased soil moisture retention, moderated soil temperature, and reduced the TSS, soil loss, runoff, and water flow rate. Tillage incorporation is not recommended since it decreased the compost/mulch effectiveness in reducing runoff and sediment losses. While the two studied areas, in semiarid and humid regions, were disparate in their characteristics, sustainable natural resource management was successfully achieved by using appropriate management practices in each case.