The sustainable development of rangeland ecosystems, the vital ecosystems providing many important ecosystem services for millions of people in the Hindu Kush-Himalaya region is presently confronted with a number of challenges. A coupled natural and human systems approach is needed to facilitate effective collaboration among social scientists, bio/physical scientists, and management practitioners to better understand how people interact with the environment in which they live. In pursuing this argument, three existing case studies, i.e. Indigenous rangeland management in Himalayan Nepal, Cultivated Grassland Systems in Eastern Qinghai-Tibetan Plateau, and Grassland Restoration in Central Qinghai-Tibetan Plateau were synthesized in this paper to address the importance of coupled natural and human systems in promoting sustainable rangeland ecosystem management in the Hindu Kush-Himalaya (HKH) region. It was concluded although the research sites and objectives were very different, that these three case studies had many commonalities that addressed the complex interactions and feedbacks between natural and human systems, and highlighted the integration of various tools and techniques from the ecological and social sciences, as well as other disciplines, in sustainable rangeland management. These case studies have offered unique interdisciplinary insights into complexities that cannot be gained from ecological or social research alone. The results from these case studies can be applied to many other coupled systems at local, national, and global levels. 相似文献
This study on the effects of ultrasonic treatment on female gametophytes ofLaminaria japonica showed that:
1.
Ultrasonic treatment had shortening effect on filaments of female gametophytes. Within certain period of time, the average length of filamentous female gametophytes was shortened.
2.
Ultrasonic treatment had emptying effect on cells. The number of empty cells increased with time of treatment. Ultrasonic treatment had harmful effect on cells.
3.
Ultrasonic treatment could break down cell walls. The combination of frequency of 20 kHz, output of 15 W, 40 s and 60 s of treatment was best for this purpose. After ultrasonic treatment, the regeneration of female gametophytes into sporophytes was effected. Female ganetophytes could not recover after too long period of treatment.