Kuwait, one of the gulf council member countries, situated in the Northeastern part of the Arabian Peninsula, experiences hyper-arid desert environmental condition due to the geographical location. Kuwait faces many c...Kuwait, one of the gulf council member countries, situated in the Northeastern part of the Arabian Peninsula, experiences hyper-arid desert environmental condition due to the geographical location. Kuwait faces many challenges in the sustainable development of the agricultural sector due to the scarcity of arable land, water resources and high rate of land degradation. So it is essential to emphasis the efficient use of the available water and soil resources in a sustainable manner and also to rehabilitate the degraded land using proper rehabilitation techniques. This study concentrates on the water harvesting and organic mulching （e.g., using date palms） methods. The study area is an artificial playa （2,500 m2）, formed through the dumping of the gravel quarries in December 2003. The application of the water harvesting and mulching technique in the study showed an improvement of soil physical properties. The average infiltration capacity has increased from 74 cm3/min to 112 cm3/min. The average difference in volume of infiltrated water was 33.5%. The bulk density and porosity of the control plot was 2 g/cm3 and 27%, respectively; while that of the treated soil was 1.5 g/cm3 and 44%, respectively. The moisture content of the treated soil was increased to 50%, more than control soil at depth 40-60 cm, and also there was a significant increase in organic matter. The temperature of the treated soil was 2 ℃ lower than the control soil at a depth of 60 cm. This study conserved the irrigation water through reducing the proportion of soil evaporation and thus creating an optimum condition for the plant growth.展开更多
Taking vertical shaft construction of cutter transformation of the Beijing underground diameter shield for example,the design and construction of cutter structure transformation under complex boundary conditions for l...Taking vertical shaft construction of cutter transformation of the Beijing underground diameter shield for example,the design and construction of cutter structure transformation under complex boundary conditions for large diameter shield were discussed.Practice about how to ensure the structure safety of the shaft as well as well-coordinated shield construction was explored,and reliable solutions were provided successfully,which can provide reference for similar projects.展开更多
文摘Kuwait, one of the gulf council member countries, situated in the Northeastern part of the Arabian Peninsula, experiences hyper-arid desert environmental condition due to the geographical location. Kuwait faces many challenges in the sustainable development of the agricultural sector due to the scarcity of arable land, water resources and high rate of land degradation. So it is essential to emphasis the efficient use of the available water and soil resources in a sustainable manner and also to rehabilitate the degraded land using proper rehabilitation techniques. This study concentrates on the water harvesting and organic mulching （e.g., using date palms） methods. The study area is an artificial playa （2,500 m2）, formed through the dumping of the gravel quarries in December 2003. The application of the water harvesting and mulching technique in the study showed an improvement of soil physical properties. The average infiltration capacity has increased from 74 cm3/min to 112 cm3/min. The average difference in volume of infiltrated water was 33.5%. The bulk density and porosity of the control plot was 2 g/cm3 and 27%, respectively; while that of the treated soil was 1.5 g/cm3 and 44%, respectively. The moisture content of the treated soil was increased to 50%, more than control soil at depth 40-60 cm, and also there was a significant increase in organic matter. The temperature of the treated soil was 2 ℃ lower than the control soil at a depth of 60 cm. This study conserved the irrigation water through reducing the proportion of soil evaporation and thus creating an optimum condition for the plant growth.
文摘Taking vertical shaft construction of cutter transformation of the Beijing underground diameter shield for example,the design and construction of cutter structure transformation under complex boundary conditions for large diameter shield were discussed.Practice about how to ensure the structure safety of the shaft as well as well-coordinated shield construction was explored,and reliable solutions were provided successfully,which can provide reference for similar projects.
