Potential Impacts of Climate Change on Land Degradation and Desertification

Land degradation and desertification have been graded as a major environmental and social dispute in most of the emerging countries. Changes in temperature, wind speed, and precipitation patterns will influence plant biomass production, land use, land cover, soil moisture, infiltration rate, runoff and crop management, and ultimately, land degradation. Close relations between climate change and land degradation processes have been perceived in the past decades. Climate change models and land use models should be combined with hydrologic/erosion models to accurately compute or predict climate change impacts on land degradation. This chapter introduces the advancements in modeling of impact of climate changes in land degradation and need for the critical investigation to better understand and forecast the responses of land degradation processes to a changing climate in the future.

Perception of tools for assessing on-farm nutrient losses and mitigation options

<p>This research focuses on the prominent issue of degraded water quality in New Zealand caused by the intensification of agricultural land use, resulting in increased levels of diffuse pollutants such as sediment, nitrogen and phosphorus in waterways (Duncan, 2017). Degraded water quality is a critical issue that needs to be addressed both socially and scientifically. It needs to be addressed socially as human behaviour is influencing this degradation, and the science is needed to further our understanding and implementation of the best mitigation solutions. The aim of this study was to evaluate how information surrounding potential nutrient mitigation measures provided by decision support tools is understood and interpreted by farmers facing tightening environmental regulations and a changing social outlook on environmental sustainability. To achieve this aim, the following activities were conducted: (i) A review of current theories and tools available to understand and encourage pro-environmental behaviour. (ii) A case study using the Land Utilisation Capability Indicator (LUCI) model to determine stakeholder engagement was carried out through interviews with 6 farmers in the Mangatarere Catchment. The review showed that while information alone does not drive behaviour change, it is an essential component that when used in collaboration with other methods and incentives, can be very successful (Kennedy, 2010; Mackenzie-Mohr, 2000; Stern, 2000). From this review a method that was identified as having huge potential in terms of managing water quality was the use of land use models alongside targeted on-farm advice (Bouraoui & Grizzetti, 2014). To understand the stakeholder perception and uptake of the information this method provides a case study was carried out using the LUCI model with 6 farmers in the Mangatarere Catchment. The results showed that LUCI proved to be a valuable tool for both the case study farmers and the wider farming community. Farmer feedback highlighted the importance of ensuring that information provided by such tools is communicated in a consolidated manner. This thesis shows that land use models such as LUCI have the potential to be a beneficial method of engaging stakeholders in prominent issues such as degrading water quality.</p>

Perception of tools for assessing on-farm nutrient losses and mitigation options

<p>This research focuses on the prominent issue of degraded water quality in New Zealand caused by the intensification of agricultural land use, resulting in increased levels of diffuse pollutants such as sediment, nitrogen and phosphorus in waterways (Duncan, 2017). Degraded water quality is a critical issue that needs to be addressed both socially and scientifically. It needs to be addressed socially as human behaviour is influencing this degradation, and the science is needed to further our understanding and implementation of the best mitigation solutions. The aim of this study was to evaluate how information surrounding potential nutrient mitigation measures provided by decision support tools is understood and interpreted by farmers facing tightening environmental regulations and a changing social outlook on environmental sustainability. To achieve this aim, the following activities were conducted: (i) A review of current theories and tools available to understand and encourage pro-environmental behaviour. (ii) A case study using the Land Utilisation Capability Indicator (LUCI) model to determine stakeholder engagement was carried out through interviews with 6 farmers in the Mangatarere Catchment. The review showed that while information alone does not drive behaviour change, it is an essential component that when used in collaboration with other methods and incentives, can be very successful (Kennedy, 2010; Mackenzie-Mohr, 2000; Stern, 2000). From this review a method that was identified as having huge potential in terms of managing water quality was the use of land use models alongside targeted on-farm advice (Bouraoui & Grizzetti, 2014). To understand the stakeholder perception and uptake of the information this method provides a case study was carried out using the LUCI model with 6 farmers in the Mangatarere Catchment. The results showed that LUCI proved to be a valuable tool for both the case study farmers and the wider farming community. Farmer feedback highlighted the importance of ensuring that information provided by such tools is communicated in a consolidated manner. This thesis shows that land use models such as LUCI have the potential to be a beneficial method of engaging stakeholders in prominent issues such as degrading water quality.</p>

Relationships between Peri-Urbanization Processes and Multi-Hazard Increases: Compared Diachronic Analysis in Basins of the Mediterranean Coast

This paper analyzes the relationships between the peri-urbanization process in the surroundings of cities and the increase in the synergistic dangers of flooding and water erosion. An analysis and an evaluation of the conditions causing the flooding in peri-urban basins are carried out, comparing the conditions before and after the peri-urbanization process. For this purpose, a diachronic analysis of the morphological and functional conditions of the territory that conditions flooding and associated dangers is provided. The conditions for the generation of runoff, the incorporation of solids into the flood flow, and the characteristics of urban planning are evaluated in 1956 (date before the peri-urbanization process) and 2010 (the peak of the urbanization process in the area) in order to analyze the changes in the land use model and their consequences on the increase in risk. The study is applied to four river basins (44 km2 in total) with varied land use models, in order to collect representative scenarios of the peri-urban coastal basins of the Spanish Mediterranean region. The results show that the risk factors that undergo the most significant changes are the runoff threshold, the vegetation cover, and the soil structure. It is concluded that peri-urbanization constitutes a territorial risk-causing process, and attention is drawn to the convenience of going beyond the sectoral approach in the study of hazards, coming to understand them as a multi-hazard process in which causes have a direct relationship with the underlying territorial model.

Estimating global land system impacts of timber plantations using MAgPIE 4.3.2

Out of 1150 Mha of forests designated primarily for production purposes in 2020, plantations account for 11 % (131 Mha) of area and fulfilled more than 33 % of the global industrial roundwood demand. Yet, adding additional timber plantations to meet increasing timber demand increases competition for scarce land resources between different land-uses for food, feed, livestock and timber production. Despite their significance in roundwood production, the importance of timber plantations in meeting the long-term timber demand and the implications of plantation expansion for overall land-use dynamics have not been studied in detail so far, in particular not the competition for land between agriculture and forestry in existing land-use models. This paper describes the extension of the modular, open-source land-system Model of Agricultural Production and its Impact on the Environment (MAgPIE) by a detailed representation of forest land, timber production and timber demand dynamics. These extensions allow for understanding the land-use dynamics (including competition for land) and associated land-use change emissions of timber production. We show that the spatial cropland patterns differ when timber production is accounted for, indicating that timber plantations compete with cropland for the same scarce land resources. When plantations are established on cropland, it causes cropland expansion and deforestation elsewhere. As a result of increasing timber demand, we show an increase in plantations area by 140 % until the end of the century (+132 Mha in 1995–2100). We also observe in our model results that the increasing demand for timber increases scarcity of land, and causes intensification through yield increasing technological change by 117 % in croplands by 2100 relative to 1995. Through the inclusion of new forest plantation and natural forest dynamics, our estimates of land-related CO2 emissions match better with observed data in particular the gross land-use change emissions and carbon uptake (via regrowth), reflecting higher deforestation for expansion of managed land and timber production, and higher regrowth in natural forests as well as plantations.

Development of Control Drainage Operation Model and Utilization Planning of Post-Fire Peatlands

The research aimed to determine the monthly operational groundwater control and land use patterns in fire prevention efforts on peatlands. The research method was carried out using a detailed survey scale method in the representative sample area of 20-30 ha. Observations in the field included measuring the physical properties of soils and observing hydrological components. Group discussions with the community were conducted to explore information on the causes of fires, compilation of plans for operational activities in the field, and land use models. The research results showed that in the soil depth of 0-20 cm the level of peat maturity classified as Sapric (mature), at a depth of 20-50 cm is classified as hemic and at a depth of 50-100 cm belongs to fibric (immature). The effects of blocking canal construction were very significant in raising the water level in the channel and groundwater table. However, due to the low rainfall until December 2019, the groundwater level was not yet able to raise to the point of arrangement 40 cm. Till the end of December 2019, the groundwater level was at 70 cm, however there has been an increase in groundwater level of 30 cm since the beginning of December 2019. In the rainfall conditions &lt; 2500 mm/year, blocking canal operations with a retention system have to begin in April. Agroforestry is the best model and <em>Albizia chinensis</em> (Osbeck) Merr. (sengon) in combination with pineapple plants are the best land use pattern. In addition, some short-term proposals are to provide infrastructure for firefighting, the construction of a road embankment, normalization of main rivers and canals, providing boring wells, making security control posts, training, monitoring, and providing some incentives for farmers to clear land and firefighting teams at the village level.

How modelling paradigms affect simulated future land use change

Land use models operating at regional to global scales are almost exclusively based on the single paradigm of economic optimisation. Models based on different paradigms are known to produce very different results, but these are not always equivalent or attributable to particular assumptions. In this study, we compare two pan-European integrated land use models that utilise the same climatic and socio-economic scenarios but which adopt fundamentally different modelling paradigms. One of these is a constrained optimising economic-equilibrium model, and the other is a stochastic agent-based model. We run both models for a range of scenario combinations and compare their projections of spatially aggregate and disaggregate land use changes and ecosystem service supply levels in food, forest and associated environmental systems. We find that the models produce very different results in some scenarios, with simulated food production varying by up to half of total demand and the extent of intensive agriculture varying by up to 25 % of the EU land area. The agent-based model projects more multifunctional and heterogeneous landscapes in most scenarios, providing a wider range of ecosystem services at landscape scales, as agents make individual, time-dependent decisions that reflect economic and non-economic motivations. This tendency also results in food shortages under certain scenario conditions. The optimisation model, in contrast, maintains food supply through intensification of agricultural production in the most profitable areas, sometimes at the expense of land abandonment in large parts of Europe. We relate the principal differences observed to underlying model assumptions and hypothesise that optimisation may be appropriate in scenarios that allow for coherent political and economic control of land systems, but not in scenarios in which economic and other scenario conditions prevent the changes in prices and responses required to approach economic equilibrium. In these circumstances, agent-based modelling allows explicit consideration of behavioural processes, but in doing so it provides a highly flexible account of land system development that is harder to link to underlying assumptions. We suggest that structured comparisons of parallel and transparent but paradigmatically distinct models are an important method for better understanding the potential scope and uncertainties of future land use change, particularly given the substantive differences that currently exist in the outcomes of such models.