Global Land Degradation Research Articles

Modeling the Present and Future Desertification Risk State: A Case Study in Kolli Hill, Eastern Ghats of Tamil Nadu, India

Desertification is a global land degradation problem faced both in the developed and developing countries alike. Kolli hill is one of the hills of the Eastern Ghats of India, currently undergoing conspicuous land degradation to such an extent, that it has already begun to witness an altered forest stand. Hence, the main goal of this study is to identify areas under actual and potential desertification risk by means of a modelling approach in which four indicator thematic layers (soil, climate, vegetation and anthropic pressure buffers) were overlaid in GIS environment. The cartographic data were transformed to structured numerical data (weighted layers) such that each of the layers was assigned knowledge based weightage values in relation to their influence and contribution to the process of desertification to get the final desertification risk state of the forest region. Climate models suited for the Indian condition were utilized to determine the areas under potential risk of desertification and three Representative Concentration Pathways were employed to study the pattern of desertification by the middle and the end of this century. The results of the study show the present scenario with an area of 200 km2 falling in the medium risk state and an area of 7 km2 falling in the high-risk state. On average, about 215 and 214 km2 of the forest area fall under the medium risk category, while an area of 9.5 and 8.94 km2 belong to the high risk state for the years 2050 and 2070 respectively. The areas experiencing these risk states belong to the foothills and mid slopes of the forest region and fall within the semiarid–dry sub-humid aridity zonation.

A Fifty-Year Sustainability Assessment of Italian Agro-Forest Districts

As cropland management and land use shifted towards more intensive practices, global land degradation increased drastically. Understanding relationships between ecological and socioeconomic drivers of soil and landscape degradation within these landscapes in economically dynamic contexts such as the Mediterranean region, requires multi-target and multi-scalar approaches covering long-term periods. This study provides an original approach for identifying desertification risk drivers and sustainable land management strategies within Italian agro-forest districts. An Environmental Sensitivity Area (ESA) approach, based on four thematic indicators (climate, soil, vegetation and land-use) and a composite index of desertification risk (ESAI), was used to evaluate changes in soil vulnerability and landscape degradation between the years 1960 and 2010. A multivariate model was developed to identify the most relevant drivers causing changes in land susceptibility at the district scale. Larger districts, and those with a higher proportion of their total surface area classified as agro-forest, had a significantly lower increase in land susceptibility to degradation during the 50 years when compared with the remaining districts. We conclude that preserving economic viability and ecological connectivity of traditional, extensive agricultural systems is a key measure to mitigate the desertification risk in the Mediterranean region.

Optimising diet decisions and urban agriculture using linear programming

Amidst continual global population growth, land degradation and climate change, consumers are becoming more aware of the environmental impact of their diet. People in cities are also looking to mitigate the risk of disruption to their food supply through adoption of urban agriculture (UA). It is not at all clear, however, what impact UA will ultimately have on urban food security. The informal nature of many UA enterprises makes quantification difficult, and some projections of cities “feeding themselves” appear to simply reflect untested optimism. This paper demonstrates the novel use of Linear Programming (LP) to explore different dietary preferences (high meat intake versus vegetarian), and to determine the feasibility of urban agriculture (UA) making a substantial contribution to food security. The model quantifies the maximum potential impact of locally-grown produce in terms of either reducing cost or maximising the dietary contribution. Results show that LP can be used effectively to explore optimal cropping on urban land, based on the amount of available land per capita. A key finding of this feasibility study is that the contribution of UA to realistic diets—while limited—need not be trivial. In our case study of Northern Adelaide, Australia, it appears that 10–15 % of dietary protein could be produced in a typical suburban backyard, with or without chicken meat, along with savings of around AU$1 per person per day. Both the nature of the optimal UA crop regime and its impact are shown to depend on the dietary context, especially the level of meat consumption.

Legal & Scientific Integrity in Advancing a 'Land Degradation Neutral World'

It is no secret that the fight against desertification isn't going well. In the two decades since the United Nations Convention to Combat Desertification (UNCCD) came into force, desertification has worsened considerably. Many within the desertification community and beyond are calling for a fresh approach to the problem: the establishment of a global goal to achieve a "land-degradation neutral world." However, the call for land degradation neutrality has not been universally celebrated, particularly given the questionable track record of past "no net loss" policies. This article looks at ways to advance global land degradation neutrality into a concept — and, eventually, a program — that has legal and scientific integrity, such that it delivers tangible gains. We do so by drawing on lessons learned from two ongoing, land-centered policy attempts similarly framed around goals of neutrality: the "no net loss" wetlands policy embraced by the United States' Wetlands Mitigation Banking (WMB) program, as representative of a broad class of "biodiversity offset" programs emerging around the world; and Reduced Emissions from Deforestation and Forest Degradation (REDD), an international program aimed at preserving, enhancing, and restoring forests as carbon "sinks." Three key issues emerge for further consideration on the path to a "land-degradation neutral world": (1) how to define and measure the problem — "land degradation" — in scientifically and legally meaningful ways; (2) how to successfully pursue "neutrality" as an organizing principle; and (3) how to balance the local and the global, and the public and the private, in the administration of such a program.

Soil erosion, climate change and global food security: challenges and strategies.

An overview is presented of the determined degree of global land degradation (principally occurring through soil erosion), with some consideration of its possible impact on global food security. Most determinations of the extent of land degradation (e.g. GLASOD) have been made on the basis of "expert judgement" and perceptions, as opposed to direct measurements of this multifactorial phenomenon. More recently, remote sensing measurements have been made which indicate that while some regions of the Earth are "browning" others are "greening". The latter effect is thought to be due to fertilisation of the growth of biomass by increasing levels of atmospheric CO2, and indeed the total amount of global biomass was observed to increase by 3.8% during the years 1981-2003. Nonetheless, 24% of the Earth's surface had occasioned some degree of degradation in the same time period. It appears that while long-term trends in NDVI (normalised difference vegetation index) derivatives are only broad indicators of land degradation, taken as a proxy, the NDVI/NPP (net primary productivity) trend is able to yield a benchmark that is globally consistent and to illuminate regions in which biologically significant changes are occurring. Thus, attention may be directed to where investigation and action at the ground level is required, i.e. to potential "hot spots" of land degradation and/or erosion. The severity of land degradation through soil erosion, and an according catastrophic threat to the survival of humanity may in part have been overstated, although the rising human population will impose inexorable demands for what the soil can provide. However the present system of industrialised agriculture would not be possible without plentiful provisions of cheap crude oil and natural gas to supply fuels, pesticides, herbicides and fertilisers. It is only on the basis of these inputs that it has been possible for the human population to rise above 7 billion. Hence, if the cheap oil and gas supply fails, global agriculture fails too, with obvious consequences. Accordingly, on grounds of stabilising the climate, preserving the environment, and ensuring the robustness of the global food supply, maintaining and building good soil, in particular improving its SOM content and hence its structure, is highly desirable. Those regions of the world that are significantly degraded are unlikely to support a massive population increase (e.g. Africa, whose population is predicted to grow from its present 1.1 billion to 4.2 billion by 2100), in which case a die-off or mass migration might be expected, if population control is not included explicitly in future plans to achieve food security.

Achieving Zero Net Land Degradation: Challenges and opportunities

Land degradation is extensive, covering approximately 23% of the globe's terrestrial area, increasing at an annual rate of 5–10 million ha, and affecting about 1.5 billion people globally. Such detrimental processes call for urgent and comprehensive action to halt land degradation. In this paper, we assess the causes and extent of land degradation around the world, followed by an outline of the various challenges in implementing a global Zero Net Land Degradation (ZNLD) policy. The concept of ZNLD proposes a scheme under which the extent of global degraded lands will decrease or at least, remain stable. To enable this type of scenario, the rate of global land degradation should not exceed that of land restoration. Restoration efforts should include not only croplands, rangelands, and woodlands, but also natural and semi-natural lands that do not generate direct economic revenues. The United Nations Convention to Combat Desertification (UNCCD) envisages achieving this target by 2030. Despite being seemingly ambitious, the target of ZNLD could be achieved if degraded lands are restored to a considerable extent and, at the same time, land-degrading management practices are replaced with ones that conserve soils. To enable effective implementation of these steps, it is necessary to formulate a ZNLD Protocol aimed at managing assessment actions and maintaining of supportive policies and regulations. Restoration projects could be financed through payments for improving ecosystem services, as well as other economic mechanisms. Achieving the target of land degradation neutrality would decrease the environmental footprint of agriculture, while supporting food security and sustaining human wellbeing.

Biomass Productivity-Based Mapping of Global Land Degradation Hotspots

Biomass Productivity-Based Mapping of Global Land Degradation Hotspots

An Exploration of Scenarios to Support Sustainable Land Management Using Integrated Environmental Socio-economic Models

Scenario analysis constitutes a valuable deployment method for scientific models to inform environmental decision-making, particularly for evaluating land degradation mitigation options, which are rarely based on formal analysis. In this paper we demonstrate such an assessment using the PESERA-DESMICE modeling framework with various scenarios for 13 global land degradation hotspots. Starting with an initial assessment representing land degradation and productivity under current conditions, options to combat instances of land degradation are explored by determining: (1) Which technologies are most biophysically appropriate and most financially viable in which locations; we term these the "technology scenarios"; (2) how policy instruments such as subsidies influence upfront investment requirements and financial viability and how they lead to reduced levels of land degradation; we term these the "policy scenarios"; and (3) how technology adoption affects development issues such as food production and livelihoods; we term these the "global scenarios". Technology scenarios help choose the best technology for a given area in biophysical and financial terms, thereby outlining where policy support may be needed to promote adoption; policy scenarios assess whether a policy alternative leads to a greater extent of technology adoption; while global scenarios demonstrate how implementing technologies may serve wider sustainable development goals. Scenarios are applied to assess spatial variation within study sites as well as to compare across different sites. Our results show significant scope to combat land degradation and raise agricultural productivity at moderate cost. We conclude that scenario assessment can provide informative input to multi-level land management decision-making processes.

Response of microbial activity and biomass to increasing salinity depends on the final salinity, not the original salinity

Salinization is a global land degradation issue which inhibits microbial activity and plant growth. The effect of salinity on microbial activity and biomass has been studied extensively, but little is known about the response of microbes from different soils to increasing salinity although soil salinity may fluctuate in the field, for example, depending on the quality of the irrigation water or seasonally. An incubation experiment with five soils (one non-saline, four saline with electrical conductivity (ECe) ranging from 1 to 50 dS m−1) was conducted in which the EC was increased to 37 ECe levels (from 3 to 119 dS m−1) by adding NaCl. After amendment with 2% (w/w) pea straw to provide a nutrient source, the soils were incubated at optimal water content for 15 days, microbial respiration was measured continuously and chloroform-labile C was determined every three days. Both cumulative respiration and microbial biomass (indicated by chloroform-labile C) were negatively correlated with EC. Irrespective of the original soil EC, cumulative respiration at a given adjusted EC was similar. Thus, microorganisms from previously saline soils were not more tolerant to a given adjusted EC than those in originally non-saline soil. Microbial biomass in all soils increased from day 0 to day 3, then decreased. The relative increase was greater in soils which had a lower microbial biomass on day 0 (which were more saline). Therefore the relative increase in microbial biomass appears to be a function of the biomass on day 0 rather than the EC. Hence, the results suggest that microbes from originally saline soils are not more tolerant to increases in salinity than those from originally non-saline soils. The strong increase in microbial biomass upon pea straw addition suggests that there is a subset of microbes in all soils that can respond to increased substrate availability even in highly saline environments.

Quantitative mapping of global land degradation using Earth observations

Land degradation is a global issue on par with climate change and loss of biodiversity, but its extent and severity are only roughly known and there is little detail on the immediate processes – let alone the drivers. Earth-observation methods enable monitoring of land degradation in a consistent, physical way and on a global scale by making use of vegetation productivity and/or loss as proxies. Most recent studies indicate a general greening trend, but improved data sets and analysis also show a combination of greening and browning trends. Statistically based linear trends average out these effects. Improved understanding may be expected from data-driven and process-modelling approaches: new models, model integration, enhanced statistical analysis and modern sensor imagery at medium spatial resolution should substantially improve the assessment of global land degradation.

Spatial Variability of Soil Organic Carbon in a Watershed on the Loess Plateau

Soil organic carbon (SOC) has great impacts on global warming, land degradation and food security. Classic statistical and geostatistical methods were used to characterize and compare the spatial heterogeneity of SOC and related factors, such as topography, soil type and land use, in the Liudaogou watershed on the Loess Plateau of North China. SOC concentrations followed a log-normal distribution with an arithmetic and geometric means of 23.4 and 21.3 g kg −1, respectively, were moderately variable (CV = 75.9%), and demonstrated a moderate spatial dependence according to the nugget ratio (34.7%). The experimental variogram of SOC was best-fitted by a spherical model, after the spatial outliers had been detected and subsequently eliminated. Lower SOC concentrations were associated with higher elevations. Warp soils and farmland had the highest SOC concentrations, while aeolian sand soil and shrublands had the lowest SOC values. The geostatistical characteristics of SOC for the different soil and land use types were different. These patterns were closely related to the spatial structure of topography, and soil and land use types.

African lake management initiatives: The global connection

AbstractThere is a global dimension to lake management in Africa and elsewhere that will require a concerted action not only from individual riparian states, but also from regional, continental and global communities. The current global lake threats arise from climate change, regional land degradation and semivolatile contaminants, and share the common feature that the atmosphere is the vector that spreads their impacts over large areas and to many lakes. The Great Lakes of Africa (Malawi, Victoria and Tanganyika) are particularly sensitive to these problems because of their enormous surface areas, slow water flushing rates, and the importance of direct rainfall in their water budgets. Their response times might be slow to yield a detectable change and, unfortunately, their recovery times might also be slow. It is possible for atmospheric effects to act antagonistically to the impacts of catchment change, but antagonistic effects could become synergistic in the future. Improved understanding of the physical dynamics of these lakes, and development of models linking their physical and biogeochemical behaviour to regional, mesoscale climate models, will be necessary to guide lake managers.

Energy use and economical analysis of sugar beet production in Tokat province of Turkey

The purposes of this study were to determine energy consumption of input and output used in sugar beet production, and to make a cost analysis in Tokat, Turkey. Data were collected from 146 sugar beet farms in Tokat, Turkey by using a face-to-face questionnaire performed in January and February 2005. Farms were selected based on random sampling method. The results revealed that total energy consumption in sugar beet production was 39 685.51 MJ ha −1, and accounted for 49.33% of fertilizer energy, and 24.16% of diesel energy. The output/input energy ratio was 25.75 and energy productivity was 1.53 kg MJ ha −1. Results further indicated that 82.43% of total energy input was in non-renewable energy form, and only 12.82% was in renewable form. Economic analyses showed that profit–cost ratio of farms was 1.17. The highest energy cost items were labor, land renting, depreciation and fertilizers. Although intensive energy consumption in sugar beet production increased the yield, it also resulted in problems such as global warming, land degradation, nutrient loading and pesticide pollution. Therefore, there is a need to pursue a new policy to force producers to undertake energy-efficient practices to establish sustainable production systems without disrupting the natural resources. In addition, extension activities are needed to improve the efficiency of energy consumption and to sustain the natural resources.

Measuring the Productivity from Indigenous Soil and Water Conservation Technologies with Household Fixed Effects: A Case Study of Hilly Mountainous Areas of Benin

Previous articleNext article No AccessMeasuring the Productivity from Indigenous Soil and Water Conservation Technologies with Household Fixed Effects: A Case Study of Hilly Mountainous Areas of Benin*Anselme Adégbidi, Esaïe Gandonou, and Remco OostendorpAnselme AdégbidiUniversité Nationale du Bénin Search for more articles by this author , Esaïe GandonouUniversité Nationale du Bénin Search for more articles by this author , and Remco OostendorpFree University, Amsterdam and Centre for the Study of African Economies, University of Oxford Search for more articles by this author Université Nationale du BéninFree University, Amsterdam and Centre for the Study of African Economies, University of OxfordPDFPDF PLUSFull Text Add to favoritesDownload CitationTrack CitationsPermissionsReprints Share onFacebookTwitterLinkedInRedditEmail SectionsMoreDetailsFiguresReferencesCited by Economic Development and Cultural Change Volume 52, Number 2January 2004 Article DOIhttps://doi.org/10.1086/381018 Views: 73Total views on this site Citations: 5Citations are reported from Crossref © 2004 by The University of Chicago. All rights reserved.PDF download Crossref reports the following articles citing this article:Sèyi Fridaïus Ulrich Vanvanhossou, Ivan Bossima Koura, Luc Hippolyte Dossa The implications of herd entrustment practice for the sustainable use of cattle genetic resources in the (agro)-pastoral systems of West Africa: A case study from Benin, Pastoralism 11, no.11 (May 2021).https://doi.org/10.1186/s13570-020-00189-8Markus Giger, Hanspeter Liniger, Caspar Sauter, Gudrun Schwilch Economic Benefits and Costs of Sustainable Land Management Technologies: An Analysis of WOCAT's Global Data, Land Degradation & Development 29, no.44 (Oct 2015): 962–974.https://doi.org/10.1002/ldr.2429Prabodh Illukpitiya, John F. Yanagida Farming vs forests: Trade-off between agriculture and the extraction of non-timber forest products, Ecological Economics 69, no.1010 (Aug 2010): 1952–1963.https://doi.org/10.1016/j.ecolecon.2010.05.007Jan Nyssen, Wim Clymans, Katrien Descheemaeker, Jean Poesen, Ine Vandecasteele, Matthias Vanmaercke, Amanuel Zenebe, Marc Van Camp, Mitiku Haile, Nigussie Haregeweyn, Jan Moeyersons, Kristine Martens, Tesfamichael Gebreyohannes, Jozef Deckers, Kristine Walraevens Impact of soil and water conservation measures on catchment hydrological response-a case in north Ethiopia, Hydrological Processes 24, no.1313 (Mar 2010): 1880–1895.https://doi.org/10.1002/hyp.7628David K. Smith A bibliography of applications of operational research in West Africa, International Transactions in Operational Research 15, no.22 (Mar 2008): 121–150.https://doi.org/10.1111/j.1475-3995.2008.00625.x

International activities in assessing and monitoring soil degradation

AbstractThe problem of land degradation is not new, but never before has it been so widespread or affected the lives of so many people. The need for a global assessment of land degradation was highlighted by the United Nations Conference on the Human Environment in 1972. Since then, several attempts have been made to develop methodologies that will allow for systematic assessment and monitoring of global land degradation. Systematic work started in 1975, when FAO and United Nations Environment Programme (UNEP) collaborated in a study to develop a provisional method for soil degradation. This method was tested, and maps on a scale of 1:5,000,000 were produced for North Africa and the Near East. However, the method proved difficult to apply accurately, so this project was followed by another where the method was revised and refined in an effort to assess and map desertification. Again, problems were encountered because of the complexity of the subject and the lack of usable reliable data. More recently, ISRIC, using a simplified methodology and the assistance of some 250 scientists from around the world, has produced a world map of human induced soil degradation at a scale of approximately 1:10,000,000. Meanwhile, interest has been growing in the problem of nutrient depletion in developing countries and a study has been completed of N, P and K balances in the soils of 38 African countries. Although we still do not have an accurate assessment of global land degradation and no systematic monitoring is yet in place, these innovative studies have provided us with a sound basis for future work and have identified many of the practical problems of measuring land degradation, data collection and analysis that will have to be overcome before more accurate assessment and monitoring can be achieved.