黄土高原南部作物水肥产量效应的田间研究

本文采用田间试验和统计分析方法定量地研究了黄土高原南部典型旱作农田的水肥效应,得出了小麦和玉米在试验年份的水分满足程度和农田水分供需平衡过程。指出,影响该区当前作物产量提高的主要限制因素是肥力,而不是水分。本文再次明确指出土壤水库在旱农条件下作物供水调节中的不可替代作用。根据全生育期中土水势剖面的变化再次提出低土水势水分的较高有效性问题。本工作所取得的结论对发展黄土高原南部旱作农业是极为重要的。     

Benefits Approach to Leisure Applied to Sustainable Tourism Development

The Benefits Approach to Leisure (BAL), recognized as a major and badly needed "paradigm shift" in the way we conceive of and manage recreation resources, is believed to play a big role in achieving the sustainable development of tourism industry. BAL has been proved to be effective and efficient in the field of leisure and tourism in terms of its three types of benefits and two stages of production. This paper, using Aqua Zoo in Friesland, the Netherlands as a case, investigates the significance of BAL to ...