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Sustainable soil/land management for Climate-Smart Agriculture

概 念

Strategies for sustainable soil and land management for climate-smart agriculture

Land resources planning should help producers, policy makers and other stakeholders select the most appropriate land uses for a given area. It should also help create conditions that allow for the adoption of sustainable soil and land management practices that promote the conservation of soil and land in healthy landscapes and ecosystems, and restore degraded land (FAO, 2017b). See module A3 on integrated landscape management.

Chapter B7-2.1 looks at the use of systematic assessments of land potential as a means of identifying optimal land uses suitable for a specific set of economic and social conditions that can contribute to climate change adaptation and mitigation. Chapter B7-2.2 presents databases of practices that have been identified for major land-use systems that can help agricultural producers and other land users select adapted management practices for particular environmental conditions and problems that can enhance agricultural resilience and support climate-smart agriculture. These tools can also provide guidance to decision-makers who are looking to ensure that the use of land resources is based on its natural potential, avoids overexploitation and prevents any further degradation.  Chapter B7-2.3 describes tools that can support the implementation and scaling up of sustainable soil and land management practices for climate-smart agriculture. Chapter B7-3 describes the sustainable soil and land management practices that are most pertinent in this regard.

B7-2.1 Assessment of the status of soil and land resources

The assessment of the status of soil and land resources helps decision-makers understand the extent and effectiveness of existing or potential sustainable land management measures on soil conservation and land recovery; trends in land conversion and alternatives for optimal land use; and the type, extent and severity of various land degradation processes. 

There are various types of assessments that are suited to different purposes.

Soil assessments

Knowing the status and condition of soils and their properties is fundamental for making sound decisions about sustainable soil management practices that can contribute to climate-smart land use. It is crucial to carry out soil assessments, including on-site visual assessments and soil surveys, analyse the data and information, and make soil maps (FAO, 2008). Participatory field observations need to be backed up by laboratory testing for specific properties. Various conventional and digital mapping tools should be used to extrapolate the findings across a range of soil and terrains, vegetation types, and/or agro-ecological zones. Ideally, soil information will be made available as continuous maps that emphasise the soil’s geographic position and attributes. Visual soil assessments should also involve land users and be supported by technical experts to assess the soil's physical properties (e.g. texture, structure, water holding capacity and dispersion) and chemical properties (e.g. pH, nutrients and salinity). Soil test kits for quantitative chemical characterizations are available in many countries or can be ordered online. FAO has developed Visual Soil Assessment Field Guides for annual crops, olive orchards, orchards, vineyards and wheat. The United Sates Department of Agriculture has also developed a soil quality test kit for nine soil parameters (USDA and NRSC, 1998). However, the kit does not include any facility to analyse the labile soil organic carbon fraction, which are the parts of soil organic carbon that are the most rapidly  oxidized by microbial activity, and which release carbon dioxide into the atmosphere. These labile fractions of soil organic carbon are important to study in their own right, as they drive the soil food web and greatly influence nutrient cycles and biologically-related soil properties. The use of dilute, slightly alkaline potassium permanganate and calcium chloride and a colorimeter represents a simple method of estimating changes in biologically active soil organic carbon. This procedure can be conducted in the field and may provide an early indication of soil degradation or how management practices are affecting soil quality (Weil et al., 2003).

Regional assessments of soil change

The Status of the World’s Soil Resources (SWSR) is a reference document that provides global and regional assessments of soil change. It includes, for example, the hazards posed by the thawing of permafrost soils and their connection with climate change. The status report looks at the ten major soil threats to ecosystem functions, goods and services: soil erosion, soil organic carbon loss, nutrient imbalance, soil acidification, soil contamination, waterlogging, soil compaction, soil sealing, salinization, and loss of soil biodiversity. It also describes direct and indirect pressures on soils and the ways and means to combat soil degradation. A synthesis report for policy makers summarizes the major findings, conclusions and recommendations (FAO and ITPS, 2015a).

Assessment of land use, land degradation and land management practices

Slowing or stopping soil and land degradation is a core challenge for sustainable development. The degradation of soil and land has adverse impacts on food security, water quality and availability, human health, and social and economic activities (FAO and ITPS, 2015b). Addressing soil and land degradation through the sustainable management of soil and land and building up soil organic matter offers tremendous potential for climate change adaptation and mitigation. 

The Land Degradation Assessment in Drylands (LADA) and The World Overview of Conservation Approaches and Technologies (WOCAT) toolset facilitates a participatory process with land users and experts for carrying out national and local assessment of land degradation and existing land management practices; selecting the most suitable practices for the given local context; and assessing, documenting and sharing results through the WOCAT database (FAO, 2012). A harmonized set of methodologies for the assessment of land use, land degradation and land management practices have been developed at global, national, subnational and local levels.

At the national and regional level, the assessment of the status, causes and impacts of land degradation, as well as the status and impacts of conservation measures and sustainable land management practices are assessed by major land-use systems. The toolset includes the production of land-use system maps and a multidisciplinary, participatory expert assessment of these maps, which is guided by the questionnaire for mapping.

The main purpose of LADA-Local level assessment manual is to provide a standard methodological approach and a toolkit for assessing, in collaboration with local stakeholders and communities, local land degradation processes, their causes and impacts. The LADA approach also assesses the extent to which natural resources, such as soil, water and vegetation, and landscapes and ecosystems are being conserved and/or improved through sustainable land management practices. The approach can also be used to assess the impact of implementing sustainable land management in improving the status of land resources. The methodology is documented in the two interlinked parts of the LADA-Local level assessment manual: 

Part 1 - Planning and Methodological Approach, Analysis and Reporting (available in English, Chinese, French and Spanish)

Part 2 - Field Methodology and Tools (available in English and French)

B7-2.2 Information systems that support the selection of sustainable soil and land management practices

The selection of suitable sustainable soil and land management practices is a clearly a critical element for the success of any implementation programme designed to foster climate-smart agriculture. For a given set of biophysical and socio-economic conditions, the key question is: what are the potential technologies or practices that the farmers and other land users could adopt that would enable them to better adapt to the impacts of climate change and mitigate these impacts? Practitioners need information to facilitate the selection of suitable practices from a variety of alternatives that have been developed locally and globally. Listed below are three examples of information systems that can provide guidance in this area.

  • The World Overview of Conservation Approaches and Technologies (WOCAT) is an established global network that supports innovation and decision-making processes in sustainable land management. The overall goal of the WOCAT Network is to unite international efforts in knowledge management and decision support for scaling up sustainable land management among all stakeholders, including national governmental and non-governmental institutions and international and regional organizations and programmes. The network provides tools that allow sustainable land management specialists to identify what actions are needed and where, and share their knowledge in land management. These tools assist specialists in their search for appropriate sustainable land management technologies and approaches; support them in making decisions in the field; help them in planning measures to promote the adoption and scaling up of identified best practices. WOCAT provides the users with over 500 technologies and approaches that have been documented around the world and in various agricultural ecosystems and socio-economic settings. This also provides assistance to agricultural producers and other land users in choosing the most appropriate sustainable land management practices. WOCAT has also prepared a questionnaire on climate change adaptation. The questionnaire can be used to assess experienced and projected exposure of a given technology or practice to gradual climate changes and climate-related disasters (see module C5 on the synergies between disaster risk reduction and climate-smart agriculture); define and assess the experienced and projected risks and potentials, and the sensitivity of the technology or practice; and determine the experienced and projected adaptive capacity to gradual climate changes and climate-related disasters. The results can provide assistance to agricultural producers and other land users in selecting a sustainable land management technology that will enhance their adaptability under the current prevailing conditions and under various climate change scenarios.
  • Technologies and Practices for Small Agricultural Producers (TECA) is a platform where users can find practical information on agricultural technologies and practices that can help small-scale producers in the field. The platform includes technologies and practices in crop and livestock production, forestry, fisheries and aquaculture, marketing and other areas. All the TECA technologies and practices have been tested and/or adopted by small-scale producers, are easy to replicate, and can be expected to increase production in a sustainable way. A number of these technologies and practices can also help small-scale agricultural producers adapt to climate change. The TECA Exchange Groups are online forums where the members can ask questions and connect with experts, practitioners and producers, share experiences in the field, and learn how to implement technologies and practices. The TECA platform facilitates the sharing and exchange of knowledge to support small-scale producers in selecting and adopting practical and sustainable management practices.
  • As part of the Global Soil Partnership (GSP), the Eurasian Soil Partnership Secretariat has established initiatives to facilitate targeted research and partnerships between scientists and local and national beneficiaries. These partnerships form a stable basis for long-term collaborative engagement to scale up the implementation sustainable soil management practices. Thematic areas for sustainable soil management practices are: the assessment of soil salinity; innovations for soil salinity management; practices and methods for the restoration of saline soils; guidelines and training modules for soil salinity management; the economic assessment of ecosystem services provided by soils in saline ecosystems; and the environmental impact assessment of sustainable soil management practices on soil ecosystem services in salt-affected landscapes.

B7-2.3 Tools to support implementation and scaling out of sustainable soil and land management

A substantial amount of experience has been gained about technical practices that have been tested and fine tuned for the optimal management of soil, water and land resources. These practices can reduce land degradation and enhance adaptation to climate change. However, the adoption of these technologies by farmers is remains less than what is needed to achieve tangible impacts. This is partially due to the lack of a proper enabling environment to support the uptake of technical solutions (see Chapter B7-4), and a lack of tools to ensure the selection and proper implementation of techniques and technologies suitable for the specific set of biophysical and socio-economic conditions under consideration. Identifying potential areas where specific technologies can be implemented with high chance of success significantly facilitates the scaling up of these technologies (Ziadat et al., 2015). 

In many cases, the selection and implementation of improved technologies do not usually take into consideration the specificities of the agricultural ecosystem. Consequently, the efficiency of the technology transfer programmes remain low. The concept of 'benchmarking' has been proposed as an approach that can help identify areas that are similar to those where the improved technologies were developed (Ziadat et al., 2014). This approach starts with the selection and characterization of a benchmark site in an agricultural ecosystem. Improved technologies are then developed and evaluated at this site. After the evaluation, similar areas to the benchmark site are selected within a targeted area for scaling up the technologies. 

Similarity analyses are used to find areas with characteristics that match those of the area where farmers tested, fine tuned or implemented a particular set sustainable soil and land management technologies. The generation of 'similarity maps' requires the formulation of an agreed 'expert similarity criteria', which is defined by an interdisciplinary team using the available datasets. These criteria are specific for certain area. Among the factors used to develop these criteria are the soil, climate, land use, and water resources. Land ownership type and size must be also included in the criteria. Suitability analyses are used within the similar areas to identify areas where the water and land management packages that have been developed can be applied with a high probability of success. The professionals, planners, and decision-makers can use the information and products generated from these analyses to identify suitable technologies for the targeted areas and/or communities. A follow up socio-economic analysis would be needed at the community level before implementing the interventions. The interventions should be abetted by a proper enabling environment that can provide incentives to communities to adopt the proposed changes. The results of these efforts should help decision-makers, planners, and donors identify areas for scaling up sustainable water and land management interventions.