SOIL – Resource Group Paper for ECL/IAD 217

March 8, 2002

Shannon Brawley, Farbice De Clerck, Cralan Deutsch,

Dana Helfer, Joe Marcotte, Emily Oakley,

Sara Prout, Ryan Sensenig and Michiko Sugawara

Issues of scale and valuation

From the public's perspective, soils function on geologic time scales, and on

spatial scales, well, dirt simply is dirt. There is little realization that soils are tremendously dynamic at both temporal and spatial scales. However, terms such as the breadbasket of the US, the Fertile Crescent, and the Nile Valley exemplify the cultural importance that is actually placed on soil quality in the agricultural sense. Several soil properties do work on large scales, but others such as pH, nitrogen content, and phosphorus levels can change within millimeters surrounding a plant's root. Important features such as soil texture and electrical conductivity can chance within meters and are clearly represented by vegetational changes across the landscape. Soil properties, which change on small spatial scales also, tend to change rapidly, whereas properties such as soil texture take decades to centuries to change. Soil formation can indeed function on a geologic time scale, but current rates of erosion force us to consider rates of soil loss, and formation at a decadal scale. For soils to be sustainably managed, we must become aware of our impact on their properties at local and annual scales.

Arguably more than any other resource area, soils are valued explicitly for their productive and economic value in producing agricultural products or primary productivity in terrestrial systems. Economically, soils are valued for their multiple uses that proceed well beyond agriculture. Soils are "mined" and sold for construction, landscaping, horticulture, and mineral uses. In situ soil is often not valued by volume, rather for its ability to produce a "crop" of interest. In this sense, soil might be equivalent to "land" and valued as an entire ecosystem.

Ecological valuation of soils is explicitly related to soil properties and functions. Although soils are highly prized for their structuring role in all terrestrial ecosystems (through their provision of water, nutrients, and habitat for micro-organisms), assessing soil quality becomes increasingly complex because these properties vary drastically across even very short spatial scales (Buol, 1995). Soil science has developed an intricate taxonomy to classify soils based on these traits. A soil's chemical (mineral type, moisture, temperature), biological (microbes, fungi, organic composition, soil fauna), and physical properties (texture, porosity, permeability, structure) are products of unique interfaces between an area's climate, slope, rock type, and biota over time. Therefore, the quality of a soil can be valued for its ability to grow plants, store and filter water, or provide a solid foundation for construction depending on these properties.

Cultural values of soil may be extremely heterogeneous over rather small geographical scales, due to the inherent diversity of soils and their multiple uses. Soils are "owned" more discretely than fisheries or biodiversity resources and there exists a deep literature of human interaction with earth both as a resource (pottery, construction) and source of nourishment. Critchley et al. (1994) highlight the diverse indigenous soil conservation practices worldwide that link communities to the specificity of their soil resources. Key to sustainable management of soils is an approach that embraces particular and relevant information about a specific site and its managers. Zimmerer (1993) calls for specificity in soil management that avoids 'spatial overexaggeration' and treats erosion as a product of abiotic, biotic, and social pressures, which in his Andes study strongly includes off farm labor pressures.

Ownership, property regimes and the governing social and political systems

Although most commonly associated with private ownership, soils are at once private, state, and common property. This diverse dynamic of ownership has tremendous impact on soil management and conservation. The nature of private property is to allow broad individual freedom in determination of use and management, which is at odds with the almost open access importance of soil quality and preservation. The perception or view on how the soil or land management techniques are utilized varies depending on cultural background, economics, experience and education. Mountjoy (1996) stresses the importance of the social and cultural contexts of individual behavior, as well as institutional factors such as access to credit, land tenure, and market forces as key processes that effect erosion rates.

Regional and national governments uphold the rights of individuals to utilize their land in privately determined ways that generally do not hold them accountable to the wider public, except in extreme cases of pollution or degradation. International non-governmental organizations often represent the issues of developed countries and their concern over soil erosion and pollution. Local organizations are more often producer or farmer-based, advocating for local rights and responsibilities in soil conservation. This private versus public debate in many respects mirrors the traditional versus scientific perceptions of soil conservation (Critchley et al., 1994). Farmers and other land users view their land in terms of output and production whereas scientists are interested in dissecting and identifying the properties of soil structure and quality (Kennedy and Papendick 1995:243). The contrast between soils as agents of livelihoods with soils as independent ecosystems and habitats plays out in the regulations of soil use. The structure of regulations of soil use directly influences approaches to management. Ultimately, however, it is in both private and public interests to ensure protection from soil loss that has created a diverse set of solutions and practices addressing soil conservation

Integrative solutions

For decades, the focus of soil conservation was on technological solutions with little consideration for how these technologies were adopted and perceived by those using them. But today, local, community-based leadership and participation have become central concepts in soil conservation research and programs. Soil management is more complex than it appears at first. Degradation is a result of a variety of factors--many of them social, such as poverty, population, socio-economic status, land distribution, civil wars and labor availability (Zimmerer, 1993). Studies focusing on the social context of behavior and local perceptions of soil degradation show how these social factors can be constraints and barriers to adopting appropriate technologies. It therefore becomes important to involve local communities in identifying problems and creating conservation solutions (Mountjoy 1995). For this reason, technical advisors, policy makers and developmental agencies are now looking at valuable environmental knowledge of indigenous peoples around the world.

The technological innovations and possible solutions for the sustainable management of soils are as diverse and varied as the multitude of situations and circumstances under which they might be applied. In the case of erosion, soil conservation technologies like ridge planting, no-till cultivation, crop rotations, strip cropping, mulching, agroforestry, terracing, contour planting, cover crops, and windbreaks, can all serve to reduce rates of erosion if carried out with minimal plowing (Pimentel et al., 1995). Diversion canals, sediment basins, and surface and buried drain pipes can be utilized to minimize erosion in and around roads and gullies (Mountjoy, 1996). Indigenous dryland soil conservation techniques include examples of appropriate local strategies and regimes for soil conservation for small-scale farmers, but are not limited to vegetative strips, trash lines, wooden barriers, pits/basins, earth/stone bunds and terraces, and flood/rain water harvesting. (Critchley et al.)

The principle economic tools and policies to address soil degradation directly correspond to farmer incentives and constraints to the adoption of soil-conserving techniques of management. Accordingly, Zimmerer (1993) specifies that farmer access to land, labor, and capital, constitute the main agrarian differentiation upon which the ability for farmers to intensify production (sustainably) rests. Consequently, Sain and Barreto (1996) argue that sustainability seeking conservation practices must embrace and integrate conservation components with productivity components. Important variables include, but are not limited to: access to migration and wage labor, access to land and size of land, availability of appropriate technology, and the economic role played by cash crops. Therefore any economic policies that affect these variables should be considered. Examples are: land tenure and ownership, access to credit, national currency value, provision of extension services, and migratory patterns of labor. These factors represent macro-policies, but the take-home lesson is that each region presents microvariations of both soil fertility and economic constraints to technology adoption (Lal & Stewart 1995).

Integrated solutions to soil management require the input of both the scientific and local communities. Policy and implementation programs must address the requirements of soil as both a private and a public good. Technological solutions are ineffective at dealing with soil degradation, unless the social and economic factors are addressed in conjunction with the environmental ones. Ultimately, the approach must be a collaborative process between land users, policy makers, scientists and other actors on the resource. The understanding of values, incentives, and benefits for each participant is crucial to community level adoption of conservation programs.

References:

Buol, S.W. 1995. Sustainability of Soil Use. Annual Review of Ecology and Systematics 26:25-44.

Critchley, W.R.S., C. Reij and T.J. Willcocks. 1994. Indigenous soil and water conservation: a review of the state of knowledge and prospects for building on traditions. Land Degradation & Rehabilitation 5:293-314.

Kennedy, A.C. and R.I. Papendick. Microbial Characteristics of Soil Quality. Journal of Soil and Water Conservation. May-June 1995, (pp. 243-248).

Lal, R. and B.A. Stewart. 1995 Managing Soils for Enhancing and Sustaining Agricultural Production. In Lal, R. and B.A. Stewart, eds. Soil Management: Experimental Basis for Sustainability and Environmental Quality. Boca Raton, FL: CRC Lewis Publishers, pp. 1- 9.

Lindert, Peter. 1996. Soil Degradation and Agricultural Change in Two Developing Countries. University of California, Davis Agricultural History Center Working Paper No. 82.

Mountjoy, Daniel C. 1996. Ethnic Diversity and the Pattern Adoption of Soil Conservation in the Strawberry Hills of Monterey, California. Society and Natural Resources 9:339-357.

Pimentel, David et al. 1995. Environmental and economic costs of soil erosion and conservation benefits. Science 267:1117-1123.

Sain, Gustavo and Hector Barreto. 1996. The adoption of soil conservation technolgy in El Salvador: linking productivity and conservation. Journal of Soil and Water Conservation 51(4): 313-321.

Zimmerer, Karl. 1993. Soil erosion and labor shortages in the Andes with special reference to Bolivia, 1953-91: Implications for “Conservation with Development.” World Development 21: 1659-1675.