Affiliations: College of Resources and Environmental Science, China
Agricultural University, Beijing 100094, China | Department of Urban and Environmental Science, Peking
University, Beijing 100871, China
Abstract: Agroecosystem functional assessment indicators provide a necessary
bridge between decision-makers and scientists. The development of acceptable
indicators, however, remains a difficult task because the current knowledge and
understanding of ecosystems is not sufficient to allow an objective assessment
of all ecosystem functions. These difficulties were summarized from three
perspectives. First, there are difficulties in individual function assessment.
Of the four functions associated with agroecosystems-energy flow, materials
cycling, information flow and value flow – data on material cycling and
information flow remain difficult to obtain and the indicators relatively
immature. Secondly, there are difficulties of integration. During the
assessment process, the integration of the agroecosystem functions remains the
biggest obstacle. Until now, there has been no practical or effective
methodology established to resolve the problem. At present, the makeshift
approach has been to weight the various indicators and then add them together.
Thirdly, there is the problem of obscure concepts and concept confusion. When
assessments of agroecosystems are conducted, concepts such as structure,
function, benefit, and resource utilization are used extensively. To date, no
logical relationship (either real or implied) has been developed between any of
these concepts. Are they causes and results such that the relationship between
them is linear, or are they independent from one another such that the
relationship is parallel? Thus far, the essence of this question is yet to be
explored.
