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There is an implementation gap between government plans and land-use changes at the local level in the Vietnamese Mekong Delta. This stands in the way of the sustainable development of the delta, especially in the face of environmental degradation, climate change, and water-use conflicts. To narrow the gap between plans and practice, the government needs a better understanding of what drives land-use decisions at the farm level. Our research developed and applied a multi-scale framework to identify the principal drivers of land-use changes at the farm level in the Vietnamese Mekong Delta over the past 40 years. We conducted semi-structured interviews with 31 farmers in the highly flooded zone, then used transcript analysis to quantify the influence of the drivers mentioned by farmers. We found drastic shifts in land uses, predominantly towards rice intensification. Among the 43 change drivers the farmers mentioned, those operating at the regional scale were particularly influential, including the activities of local authorities, neighborhood effects, and the development of water management infrastructure. Market factors have become more prominent in the last two decades, motivating farmers to shift from double to triple rice or to gradually diversify into vegetables. However, agricultural diversification remains limited by the agro-hydrological context, which favors triple rice cropping, as well as household scale factors such as natural and physical assets of the farm, household capital, and labor capacity. The local community also played a key role in land-use change, though with a double-edged effect, both delaying implementation of central government policy and forcing farmers to follow the majority's decision. [ABSTRACT FROM AUTHOR]

Policies supporting rice production and investments in water infrastructure enabled intensification and diversification of farming systems in the Vietnamese Mekong Delta (VMD) over the past 20 years. Yet, demands of food security, economic development, and climate change continue to pose diverging and often conflicting challenges for water resources management in the upper, central, and coastal zones of the delta. The major changes effected in the VMD’s hydrological regime and land-use patterns are acknowledged in the literature, but few studies have examined the interplay between these dynamics at the delta scale. Based on time-series maps and statistical data on land-use, flooding, and salinity intrusion, we investigated the interrelations between land-use dynamics and changes in hydrological regime across the VMD in three representative periods. Land-use was found to be highly variable, changing by 14.94% annually between 2001 and 2012. Rice cropping underwent the greatest change, evolving from single cropping of traditional varieties towards double and triple cropping of high-yielding varieties. Aquaculture remained stable after rapid expansion in the 1990s and early 2000s. Meanwhile, flooding and salinity intrusion were increasingly controlled by hydrological infrastructure erected to supply freshwater for agriculture. Effects of this infrastructure became particularly evident from 2001 to 2012. During this period, spatial and temporal impacts on flooding and salinity intrusion were found, which extended beyond the rice fields to affect adjacent lands and livelihood activities. Unforeseen effects will likely be aggravated by climate change, suggesting a need to rethink the scale of planning towards a more integrated hydrologic approach. [ABSTRACT FROM AUTHOR]

Land-change models are increasingly used to explore land-change dynamics, as well as for policy analyses and scenario studies. In this paper we review calibration and validation approaches adopted for recently published applications of land-change models. We found that statistical analyses and automated procedures are the two most common calibration approaches, while expert knowledge, manual calibration, and transfer of parameters from other applications are less frequently used. Validation of model results is predominantly based on locational accuracy assessment, while a small fraction of the applications assessed the accuracy of the generated land-use or land-cover patterns. Of the reviewed model applications, thirty-one percent did not report any validation. We argue that to mature as a scientific tool, and to gain credibility for scenario studies and policy assessments, the validation of land-change models requires consideration of challenges posed by uncertainty, complexity, and non-stationarity of land-change processes, and equifinality and multifinality of land-change models. [ABSTRACT FROM AUTHOR]

Abstract: Land cover and land use are important information sources for environmental issues. One of the most important changes at the Earth''s surface concerns land cover and land use. Knowledge about the location and type of these changes is essential for environmental modeling and management. Remote sensing data in combination with additional spatial data are recognized as an important source of information to detect these land cover and land use changes. In this paper, we introduce the Dutch multi-date land use database (LGN). Today there are six versions of the LGN database (LGN1–LGN6) based on satellite imagery of respectively 1986, 1992/1994, 1995/1997, 1999/2000, 2003/2004 and 2007/2008. With the completion of LGN6 a time-series of land use databases covering 20 years became available. The different databases were produced according to different methodologies. The resulting inconsistencies for monitoring land use changes and possible solutions are the main themes of this paper. Emerging user requirements, increased data availability and technical improvements lead to methodological differences between the LGN5 and LGN6 Dutch land use database. Monitoring of land use changes by integrating independent spatial datasets results in a mixture of real and methodological changes. A methodology is applied to detect real land use changes for a limited number of land use monitoring classes. The detected real changes have a high probability (almost 95%) that they are real changes. Next to these real changes, differences exist between LGN5 and LGN6, i.e. so-called methodological land use changes, being the result of methodological adaptations over time. [Copyright &y& Elsevier]

Land-use change models are typically calibrated to reproduce known historic changes. Calibration results can then be assessed by comparing two datasets: the simulated land-use map and the actual land-use map at the same time. A common method for this is the Kappa statistic, which expresses the agreement between two categorical datasets corrected for the expected agreement. This expected agreement is based on a stochastic model of random allocation given the distribution of class sizes. However, when a model starts from an initial land-use map and makes changes to it, that stochastic model does not pose a meaningful reference level. This paper introduces K Simulation, a statistic that is identical in form to the Kappa statistic but instead applies a more appropriate stochastic model of random allocation of class transitions relative to the initial map. The new method is illustrated on a simple example and then the results of the Kappa statistic and K Simulation are compared using the results of a land-use model. It is found that only K Simulation truly tests models in their capacity to explain land-use changes over time, and unlike Kappa it does not inflate results for simulations where little change takes place over time. [Copyright &y& Elsevier]

Abstract: In land administration (LA), the right to exercising property/ownership rights on land is based on cadastral processes of adjudication, survey and rights registration. Private ownership rights are now being taken up in pastoral areas, where they must contend with pastoralists’ land rights. Pastoral land use requires seasonal migrations determined by climatic conditions. This study aimed to find out how well the existing land laws and property rights in LA are able to serve the requirements of pastoralists land use, identify mismatches and put forward possible solutions. A case study was carried out in the Samburu–Laikipia–Isiolo–Meru landscape in Kenya. Data on the degree of livestock dependency among pastoralist communities, the spatial extent and patterns of dry season migrations, the resulting encounters between herders’ and non-pastoralist land use actors, and the perceptions of land rights held by actors were collected through a variety of methods and analysed. The results show that pastoralism is still active. The migration corridors reveal that herders maintain extensive dry season mobility, even though some of the corridors currently overlap with areas where land is privately owned by non-pastoralist land use actors. Moreover, the results show that most non-pastoralist land use actors have their land rights registered, but seasonal encounters with migrating pastoralists persist as pastoralists continue to exercise customary rights of communal use. We conclude that existing land laws and property rights in LA are suitable for sedentary land use, but do not address how to serve pastoralists land rights in time and space. The pastoralist''s migration routes and patterns obtained indicated that it is possible to predict where pastoralists will be at a given time/drought period. This information could be used by decision makers and land administrators to identify where and when pastoralists’ land rights apply. This could provide the foundation for including pastoralists’ spatiotemporal land rights in LA. Arguments emphasize that adjudication, surveys and registration of rights should focus not only on ownership and full control of land, but also on defined periods when spatiotemporal mobility and access rights could be granted to pastoralists. [Copyright &y& Elsevier]

Land-use/cover change (LUCC) is a complex process that includes actors and factors at different social and spatial levels. A common approach to analyse and simulate LUCC as the result of individual decisions is agent-based modelling (ABM). However, ABM is often applied to simulate processes at local scales, while its application in regional studies is limited. This paper describes first a conceptual framework for ABM to analyse and explore regional LUCC processes. Second, the conceptual framework is represented by combining different concepts including agent typologies, farm trajectories and probabilistic decision-making processes. Finally, the framework is illustrated through a case study in the Netherlands, where processes of farm cessation, farm expansion and farm diversification are shaping the structure of the landscape. The framework is a generic, straightforward approach to analyse and explore regional LUCC with an explicit link to empirical approaches for parameterization of ABM. [ABSTRACT FROM AUTHOR]

Abstract: Incomplete information is one of the main constraints for decision-making, which are then by definition risky. In this study, formal risk concepts were introduced in decision-makers’ meetings according to local demands and following a participatory approach, as a first step towards integrating risk assessment into rural decision-making in Santa Catarina, Brazil. Semi-structured interviews and meetings were conducted with extensionists and farmers. The following information was presented and discussed: (1) the time series and frequency distribution of maize yield predictions, simulated by the GAPS computer program for 16 feasible planting dates, representing climatic risks, both within and between years; and (2) a simple economic analysis (gross margin) and income probabilities for seven land-use options over a recent five-year period, followed by an interactive exercise where probabilities of achieving user-supplied target gross margins were calculated according to participants’ actual information, using the computer program @RISK. This paper also investigates decision-makers’ attitudes towards risk, and how these were influenced by objective information. Although results from a study such as this are not definitive, considering that the effects of the information on actual decision-making require some time to become evident, it was already possible to conclude that the risk-orientated information presented according to local demands and following a participatory approach had a positive impact on decision-makers’ understanding and perceptions. This approach should be further explored to effectively integrate risk assessment into rural decision-making. [Copyright &y& Elsevier]

Focuses on land use modelling. Use of agents in spatial planning; Bottom-up modelling concept; Spatial planning intentions.

• We proposed a framework of resilience in the context of coupled Social-Ecological Systems (SES). • A stylized agent-based model of a land use system was implemented as an example of SES to investigate system resilience. • Internal mechanisms increased the ability of the system to recover from external shocks. • Feedbacks resulted in different regimes of crop cultivation, each with a distinctive set of functions. • Resilience is not a generic system property, but strongly depends on what system function is considered. Dynamics of coupled Social-Ecological Systems (SES) result from the interplay of society and ecology. To assess SES resilience, we constructed an Agent-Based Model (ABM) of a land use system as a stereotypical example of SES and investigated how resilience of the represented system is affected by both external disturbances and internal dynamics. The model explicitly considered different aspects of resilience in a framework derived from literature, which includes "resilience to", "resilience of", "resilience at", "resilience due to", and "indicators of resilience". External disturbances were implemented as shocks in crop yields. Internal dynamics comprised of two types of social interaction between agents (learning and cooperation), an ecological feedback of soil depletion and an economic feedback of agglomeration benefits. We systematically varied these mechanisms and measured indicators that reflected spatial, social, and economic resilience. Results showed that (1) internal mechanisms increased the ability of the system to recover from external shocks, (2) feedbacks resulted in different regimes of crop cultivation, each with a distinctive set of functions, and (3) resilience is not a generic system property, but strongly depends on what system function is considered. We recommend future studies to include internal dynamics, especially feedbacks, and to systematically assess them across different aspects of resilience. [ABSTRACT FROM AUTHOR]

Land use/cover change (LUCC) is often the cumulative result of individual farmer''s decisions. To understand and simulate LUCC as the result of local decisions, multi-agent systems models (MAS) have become a popular technique. However, the definition of agents is not often based on real data, ignoring the inherent diversity of farmers and farm characteristics in rural landscapes. The aim of this paper is to describe an empirical method that defines an agent typology and allocates agents into the different agent types for an entire region. This method is illustrated with a case study in the Netherlands, where processes of farm expansion and diversification of farm practices take place. Five different agent types were defined and parameterized in terms of views, farm characteristics and location. Despite its simplicity, this empirical method captures several relations between farmers’ views, farm characteristics and land-use decisions and strategies. This approach is a step forward in multi-agent systems of land use/cover change (MAS/LUCC) to include the diversity of land-use decisions and strategies in regional studies by empirically defining, parameterizing and allocating different agent types. [Copyright &y& Elsevier]

Abstract: The relationship between landscape pattern and the function of nutrient reduction in the natural reed marsh of Liaohe Delta is studied with the help of some landscape metrics. The results discovered that not all the metrics selected are explanative in representing the function of nutrient reduction. Network connectivity, area size, and source to centre metrics are closely related to the simulation results from different pattern scenarios, while other metrics like area-weighted mean shape, fractal, contagion and aggregation are not related with the reduction process at all. Different metrics should be chosen according to the purpose of the study, based on the criteria of simplicity, generality and ecological meaning. [Copyright &y& Elsevier]