Ecological impact assessment
This considers how organisms, rather than people, will be affected by activities (Westman, 1985:86; Duinker, 1989). Recently the expression has been applied to the description and evaluation of the ecological baseline used by EIA. More accurately, ecological impact assessment is concerned with establishing the state of the environment, whereas EIA focuses on predicted and actual effects of change. Treweek (1995a; 1995b) has reviewed ecological impact assessment and reported it was a valuable support for EIA. An aspect of ecological impact assessment which is growing in importance is its application to biodiversity loss (Hirsch, 1993).
Ecological impact assessment may rely on selected ecosystem components as indicators or on ecosystem modelling. Ecosystem function can be complex and often is poorly understood, making accurate assessment difficult.
Habitat evaluation
Habitat evaluation seeks to assess the suitability of an ecosystem for a species or the impact of development on a habitat (Suter, 1993:8). There may be more than one habitat affected by a development, in which case each is dealt with separately. This approach has been used by the US Fish and Wildlife Service, in assessments of the impacts of US federal water resource development projects, and by the US Army Corps of Engineers (Canter, 1996:390).
Land use planning, land classification, land appraisal, land capability assessment, land suitability assessment, land evaluation and terrain evaluation
Land use planning is a process which may operate at local, regional or national scale; land capability assessment, land appraisal, land evaluation, land suitability assessment and terrain evaluation feed into that process. A land use survey indicates the situation at the time of study, and is not the same as a capability classification, which looks to the future. There are various approaches and methods for land use classification, e.g. the Ecological Series Classification or the Holdridge Life Zones System. Often the land use planning approach adopted depends on a country’s politics.
It is widely felt that land use planning is a valuable ingredient of EIA and in the
quest for sustainable development and that EIA can feed into land use planning. In practice the two are often poorly integrated.
Land capability assessment, land evaluation and land appraisal generally follow a proactive approach similar to that of EIA (scoping, data collection, evaluation, presentation of decision) in the production of a land capability classification or land evaluation (Beek, 1978; Patricos, 1986). Some approaches consider a range of factors, which might include the concept of carrying capacity, others just soil characteristics and slope. The end product is a description of landscape units in terms of inherent capacity to produce a combination of plants, animals, etc.; it is also likely to reflect government development goals, market opportunities, labour availability and public demands (e.g. terraced agriculture may be possible but labour is not available).
Simple inventories of land use and, to a limited extent, capability were made in medieval times—notably the Domesday Book. Modern land capability classification was developed by the US Soil Conservation Service in the 1930s in response to problems like the US Dust Bowl. Linked to consideration of conservation and development, land capability classification can lead to a land suitability assessment (a rating of landscape units showing what development they might best support).
Land suitability assessment may depend on overlay maps of various landscape or development attributes, or direct field observation of clues (something local people may traditionally do) —e.g. seek distinctive plants indicative of good soil.
Geographical information systems (GIS) and remote sensing are increasingly applied to land capability assessment.
Universal Soil Loss Equation The Universal Soil Loss Equation (USLE) is a predictive tool which uses data on a wide range of parameters to estimate and predict average annual soil loss. It was developed in the 1930s by the US Soil Conservation Service and was improved in 1954 and again in 1978 by the US Department of Agriculture. It is widely used by planners and consultants to check on existing and likely future soil loss and to select appropriate agricultural practices and crops to sustain production. Developed in midwestern USA, it has been modified to make it suitable for other environments, so there are numerous revised versions (Hudson, 1981:258). The USLE should be used with caution: problems arise when data are imprecise or unavailable and it is best applied in situations where water rather than wind erosion occurs (although there are modified versions intended to cope with wind erosion). A typical form of the USLE is:
A = (0.224) RKLSCP where:
A = soil loss;
R = rainfall erosivity factor (degree to which rainfall can erode soil);
K = soil erodability factor (soil vulnerability to erosion);
L = slope length factor;
S = slope gradient factor;
C = cropping management factor (what is grown and how);
P = erosion control practice factor.
Agroecosystem assessment
The agroecosystem zones concept was promoted by the FAO (1978) to provide a framework for considering a range of parameters over a limited planning term with the aim of promoting sustainable development. An agroecosystem is an ecological system modified by humans to produce food or commodities, which generally means a reduction in diversity of wildlife. Agroecosystem assessment (or analysis) evolved in Thailand and attempts rapid multidisciplinary diagnosis that includes ecological and socioeconomic concepts and parameters (Conway and Barbier, 1990:162–193).
It considers not only the farming system but also household characteristics, regional, national, even global factors likely to affect the local community. The area under consideration is zoned—often making use of a land use survey or land capability assessment. Agroecosystem assessment needs to be approached with some caution because it can lead to over-simple interpretation.
Farming systems research (FSR) is an open-ended, iterative, multidisciplinary, holistic, continuous, farmer-centred, dynamic process applied to agricultural research and development (it considers biophysical, social and economic factors and seeks to integrate their study) (Shaner et al., 1982; Brush, 1986:221). There is no single method but all approaches share five basic steps (Maxwell, 1986):
1 Classification—the identification of homogeneous groups (‘target groups’) of farmers.
2 Diagnosis—identification of limiting factors, opportunities, threats, etc., for the target group.
3 Generation of recommendations—which may require field experiments, pilot studies and/or research station work.
4 Implementation—usually working with an agricultural extension service.
5 Evaluation—which may lead to revision of what is being done.
FSR is a systems approach applied to on-farm research, and is promoted as a way of increasing farmer participation in development, and of generating improved and appropriate approaches and technology. FSR includes study of factors which may be beyond control of the farming community—world trade issues, global warming, etc. Unless some ‘off-the-shelf’ input is available, FSR usually takes time—
often two years, sometimes from five to 15 or more years.
Participatory assessment: rapid rural appraisal, participatory rural appraisal and rapid urban appraisal There is considerable overlap between agroecosystem assessment, FSR and participatory assessment approaches. The latter place more stress on participation (by the local people or target group). Participatory assessment can be defined as qualitative research or survey work which seeks to get an in-depth understanding of a community or situation. Some impact assessment experts are promoting forms of participatory impact assessment and monitoring (Yar, 1990).
Rapid rural appraisal (RRA) is a family of approaches mainly focused on land capability assessment, which seek to incorporate (or involve) local people in the process and to reduce the time and costs of preparation. It is a systematic, semi-structured activity carried out in the field by a multidisciplinary team and designed to quickly acquire new information on, and new hypotheses about, rural life. RRA has rapidly evolved since the late 1970s and there is no single standardized methodology — for an introduction see Agricultural Administration vol. 8(6), special issue (1981); IDS Bulletin vol. 12(4), special issue (1991); Conway and McCracken, 1990; Chambers, 1992). A central thesis of RRA is ‘optimal ignorance’, the idea that the amount of information required should be kept to the necessary minimum (something some EIA practitioners should also bear in mind). Another central thesis is ‘diversity of analysis’—the use of different sources of data or means of data gathering, and a range of experts, if possible, familiar with every aspect of rural life.
RRA, according to Conway and Barbier (1990:177–178) is: iterative (i.e.
processes and goals are not fixed and can be modified as an exercise progresses);
innovative (it is adapted to suit needs); interactive (team members work to get interdisciplinary insight); informal (it often relies on informal interviews); and in contact with the community. RRA can be of variable character: exploratory—like agroecosystem analysis it seeks information on a new rural topic or agroecosystem;
topical—with a specific output expected, often a hypothesis that can be a basis for research or development.
Participatory rural appraisal (PRA) approaches seek to enable local people to share, enhance and assess their knowledge of life and conditions, to plan and to act. PRA differs from RRA, in that the latter extracts information, whereas the former shares it and seeks rapport. Multidisciplinary-team studies and a stress on participatory public involvement also offer possibilities for better conduct of EIA.
However, there has been a tendency to emphasize the strengths of RRA and PRA and understate the problems which might be encountered. Sometimes ‘rapid’ seems to refer to the speed of the assessors’ fieldwork, rather than an approach designed to give useful results fast.
Rapid urban environmental assessment has been reviewed by Leitmann (1993).
Given the tremendous growth of cities, and the misery and environmental damage this can cause, it is strange that rapid urban environmental assessment has been so little applied.