Segregate or integrate nature and agriculture for biodiversity conservation? Criteria for agroforests

Noordwijk.M van, 'Segregate or integrate nature and agriculture for biodiversity conservation? Criteria for agroforests', pp.1-16, 1995

Human use of biotic resources ('agriculture' in its widest sense) and biodiversity ('nature' in its widest sense) are both needed by society at large, but there are generally conflicts between these two aspects of 'land use'. conflicts between 'nature' and 'agriculture' can be solved by segregating nature and agricultural land (maximizing agricultural production on relatively small part of the land for nature as it is possible ) or by integrating nature into agricultural land through the adaption of production system that allow sufficient agricultural production while ensuring conservation of considerable parts of biodiversity of the natural system. Multi functional forests and agroforests are examples of the 'integrate' option, intensive agriculture plus nature reserves are an example of the segregate pathway.Mixed strategies are feasible where nature reserves coexist with pure agricultural production systems for some commodities and where production system integrate nature and agriculture for the commodities. All three options have strong advocates, and it is not clear which solution is optimum under which conditions.Objective criteria are needed for distinguishing which solution may best meet the multiple goals formulated under different circumstances.A simple model is used to derive a decision scheme. It distinguishes 'internal' biodiversity of land use system and 'external' biodiversity, by requiring only a part of the area for agriculture. If two production systems are compared, biodiversity conservation will be maximized if the system is chosen with the highest agricultural productivity per unit biodiversity loss. If agricultural intensification is treated as a continuous process, a similar criterion can be used to distinguish between situations where 'segregation' or 'integrate' forms the best solution. Further research is needed to check the assumptions behind the proposed equations, to quantify the scaling function of biodiversity in order to assess the effectiveness of both ' internal' and 'external' biodiversity conservation, and to determine the feasibility of implementation of opinions in the 'real world'