tailieunhanh - Integrated Assessment of Health and Sustainability of Agroecosystems - Chapter 6

Mô tả agroecosystems, đánh giá tính bền vững và sức khỏe của họ, và đánh giá tiến bộ hướng tới mục tiêu cộng đồng và mục tiêu đã trở thành mối quan tâm lớn cho các nhà nghiên cứu, đại lý phát triển, và cộng đồng. Cách tiếp cận sức khỏe sinh thái nông nghiệp đề xuất rằng những mô tả và đánh giá có thể đạt được bằng cách sử dụng một nhóm các chỉ số chọn lựa cẩn thận (Mối quan hệ và Regier, 1980; Gosselin et al, 1991; Lightfoot và Noble, 1993; Mối quan hệ năm 1992,. | 6 Development of Health and Sustainability Indicators for a Tropical Highlands Agroecosystem INTRODUCTION Describing agroecosystems assessing their sustainability and health and assessing progress toward community goals and objectives has become of great interest to researchers development agents and communities. The agroecosystem health approach proposes that these descriptions and assessments can be achieved using a group of carefully chosen indicators Rapport and Regier 1980 Gosselin et al. 1991 Lightfoot and Noble 1993 Rapport 1992 National Research Council 1993 Cairns et al. 1993 Izac and Swift 1994 Winograd 1994 Dumanski 1994 Rapport et al. 1985 Ayres 1996 Smit et al. 1998 . There are numerous definitions of what constitutes an indicator Boyle 1998 Boyle et al. 2000 . Gallopin 1994a and Smit et al. 1998 described indicators as measurements that can be taken for a given complex phenomenon to document how it changes over time how it varies across space and how it responds to external factors. In terms of an agroecosystem an indicator has been defined as a measurable feature that singly or in combination with others provides managerially or scientifically useful evidence of ecosystem status Canadian Council of Ministers of the Environment CCME 1996 relative to a predefined set of goals. Selection of indicators is complicated by two main difficulties. First the list of potential indicators varies from one agroecosystem to another as well as among levels in an agroecological hierarchy. The second difficulty is that there are virtually an infinite number of measurable parameters at each hierarchical level of an agroecosystem Schaeffer et al. 1988 . There are however some important guidelines in the selection of agroecosystem indicators. A systems approach should be taken to select a comprehensive set of measures. In addition the choice of indicators must be explicitly guided by societal issues and values Kay 1993 that give meaning to the description or .