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Carbon emission reduction in China matters to global climate change mitigation. China has been experiencing extensive land changes, which profoundly influence terrestrial ecosystem carbon storage (TECS) and carbon emissions. Scholars have predicted influences of land changes on TECS in China with scenarios obtained from global integrated assessment models (IAMs), which lack national details. Moreover, universally existing variations in land-use intensity have not been considered when estimating influences on TECS. This study simulated changes of land-use intensity of China from 2000 to 2050 using CLUMondo under China-specified policies for sustainable development modeled by a national IAM named Threshold21-China. We proposed a more precise TECS estimation method by distinguishing land-vegetation and land-soil types. Results demonstrated that under scenario with preceding policies, the total TECS can increase by 865.5 Tg C from 2000 to 2050. Through implementing preceding policies, TECS loss by conversions from cultivated land to artificial surfaces can decline by 82 Tg C, and new TECS accumulated by increased and densified forests can increase by 73 Tg C. Mountainous and rapidly urbanizing regions are sensitively influenced and need more restrict land change management policies. This study demonstrates the significance of sustainable development policies for TECS conservation and indicates specific critical regions. • Introducing national IAM into land change simulation. • Considering land-use intensities in land change simulation. • Proposing an improved TECS estimation method. • Estimating influences of land changes on China's TECS. • TECS accumulation could be improved under sustainable policies. [ABSTRACT FROM AUTHOR]

The potential for large-scale afforestation, as a climate change mitigation strategy, has led to national afforestation targets being proposed. These targets raise many questions, including how to optimise carbon storage, whilst enhancing other ecosystem services (ES). Here, we assess how decision-making at different scales might affect the spatial distribution of new tree planting in England and hence ES provision. This was achieved by modelling the impact of afforestation on three example ES (carbon sequestration, recreation, and flood mitigation) to identify the best areas for planting at five scales of decision-making: national, regional, county, district, and parish. The modelling shows that carbon sequestration rates are relatively invariant across England (once unsuitable areas are excluded), whilst recreation and flood mitigation are more spatially variable, so full simultaneous optimisation of the three ES is not possible. Consequently, recreation and flood mitigation are also more impacted by changes in planning-scale than carbon, with the modelling showing over 200% difference between the parish and national-scenarios for flood mitigation benefits. Overall, targeted afforestation at national scale maximises ES benefits, but risks overwhelming some landscapes with trees. Targeting afforestation using smaller planning units generates more evenly distributed planting, but lower ES benefits. Our results show national-scale planning produces over 35% more combined ecosystem value than planning at parish-scale, and over 65% more than randomized planting. This highlights the benefits of targeting at a relevant scale, but also the potential trade-offs between widely-distributed new tree planting (e.g., parish-scenario), versus planting to optimise ES provision (e.g., the national-scenario). These results do not imply a single 'correct' scale for planning, but instead highlight the importance of considering the impact of a specific scale on the different ES, and that even spatial targeting at the smallest scale produces higher ES benefits than random planting. • Spatially targeting afforestation optimises provision of multiple ecosystem services. • Optimisation method demonstrated for national afforestation targets. • Substantial increase in ecosystem services over untargeted afforestation. • Service provision varies widely with governance level used to plan afforestation. [ABSTRACT FROM AUTHOR]

Environmental inequity is a common phenomenon of modern cities, particularly in the developing world where the high rates of urbanization often surpass the capacity of local governments to develop proper urban planning. In these cities the spatial distribution of environmental quality is frequently associated with socioeconomic characteristics, with vulnerable sectors often having a disproportionately larger share of environmental problems. While reducing environmental inequity is widely recognized as an important step towards more sustainable cities, decision-makers usually lack the tools and information for designing effective and efficient intervention strategies. A challenging decision is to resolve on where, among all the areas having environmental problems, efforts should be allocated first. Here we present a GIS-based framework that can help decision-makers to prioritize the spatial allocation of policy interventions at different spatial scales or administrative levels. The framework focuses on (1) identifying areas having the highest levels of environmental problems, (2) identifying areas having the highest levels of social relevance, and (3) prioritizing the allocation of resources within the areas concurrently having the highest levels of environmental problems and social relevance. To show the potential use of the framework we apply it to the city of Santiago de Chile at three different scales. Our assessment focuses on three main environmental problems currently affecting this city: urban heat, lack of green infrastructure, and air pollution. Based on the results from Santiago, we discuss how the framework can be used to help policy-makers to identify priority areas for policy intervention at their respective administrative level. [ABSTRACT FROM AUTHOR]

In Pakistan, wetlands are of primary focus as they withstand the effects of floods, recharge groundwater, and provide several services in the context of economic, cultural, and climate mitigation aspects. However, the lack of field data and huge monitoring costs hinder their sustainable management in Pakistan. In connection with this, the current study leverages Google Earth Engine (GEE), earth observation data, and machine learning-based Random Forest (RF) algorithm to evaluate spatial-temporal heterogeneities in wetlands in Pakistan between 1990 and 2020. Additionally, the first high-resolution long-term inventory of wetlands in Pakistan is presented to provide a baseline. Our results ascertain an increase in wetlands areas over the last 30 years. The swamps' area increased from 1391.19 km2 in 1990 to 8510.43 km2 in 2020 (2.62% annual change rate). Similarly, the marshes area increased between 1990 and 2020 with a ∼1.04% annual change rate. Conversely, the water area decreased from 8371.97 km2 in 1990 to 7818.34 km2 in 2020. The increase in wetlands could be associated with good conservation and planting practices in Pakistan. While these results provide important insights to implement conservation practices in the context of wetland sustainability, the resultant data is essential to the national wetlands inventory database for future evaluations. • First high-resolution long-term inventory of wetlands in Pakistan is presented. • An increase of 13687.67 Km2 in wetland areas is observed during 1990–2020. • Marshes area increased during 1990–2020 with a ∼1.04% annual change rate. • Among all wetlands, only water observed a decrease during 1990–2020 (∼7% decrease). • The recent decade (2010–2020) witnessed a decline in wetlands, which is crucial. [ABSTRACT FROM AUTHOR]

Social capital can enhance community resilience to environmental change. Productive and trusted relations among social actors and effectual social norms can help local residents share resources, information and risks. The main objective of our study is to understand the ways in which social attributes and risk considerations influence adoption of resilient economic measures by individuals for reducing potential losses due to catastrophic rainstorm and flooding. This article provides evidence from China on how social capital contributes to anticipatory adaptation to environmental change. The inquiry is based on structured interviews with local residents of Tianjin, a flood-prone port city in China, and a standard regression analysis. Findings show that the intention to make preparation increases with the levels of social expectation, social relationship, and institutional trust. Perceived risk and damage experience, however, have no significant impacts. This suggests that building social capacity and trust will be more effective in enhancing community resilience than merely increasing awareness of hazard risks. We call for greater efforts on strengthening the capacity of formal and informal communal institutions. The structural changes required, however, are challenging. [ABSTRACT FROM AUTHOR]

Reducing Emissions from Deforestation and Forest Degradation (REDD+) is considered a promising strategy to slow down deforestation rates, promote sustainable forest use, and support rural livelihoods under the umbrella of climate change mitigation. However, so far there is only little field-based knowledge on how REDD+ can go along with subsistence-based production systems and livelihoods of forest-dependent communities. We addressed this research gap by analyzing the income generation of three widespread ethnic groups (Colonists, Shuar, Kichwa) in the buffer zone of the Yasuní National Park in Ecuador to better understand their livelihoods and possible engagement in REDD+. We selected two communities of each ethnic group (close-to and far-from markets) and used household surveys to (a) calculate household incomes, (b) assess the degree of forest-dependency, and (c) discuss how REDD+ schemes can be designed along with traditional subsistence-based production systems. We found that the studied indigenous communities have a higher degree of forest-dependency and higher environmental income compared to Colonists. However, our assumption that close-to-market communities have a lower degree of forest dependency and higher cash income due to better market access and labor opportunities applies only to the Colonists and Shuar, but must be rejected for the Kichwas who gain income from timber sale. Despite these differences, all communities receive high off-farm revenues from unskilled labor provided by oil-companies and external aid. Therefore, dependency on agriculture and forestry is temporarily reduced. Under these circumstances, REDD+ provides only weak financial incentives so that the willingness to participate in REDD+ is low. [ABSTRACT FROM AUTHOR]

Abstract: Rainfall is the major driver of crop growth in Mediterranean agricultural regions and its spatial and temporal distributions determine yield potential. This study uses a long term spatial archive of rainfall observations for the Eyre Peninsula (South Australia) to estimate the spatial and temporal impacts of climate change on wheat yield. The three step process involved: (1) cluster analysis and statistical comparison to spatially distinguish heterogeneous “hazardscapes” (places that represent the physical susceptibility to hazards (Khan, 2012)); (2) using historical rainfall reliabilities to estimate the probability of receiving rainfall within a range of predefined thresholds and season for each hazardscape; (3) applying 2030 and 2070 climate change projections to determine the potential future impacts on rainfall. Nine hazardscapes were spatially differentiated each having temporally different historical seasonal rainfall reliabilities. Variations over space and time mean that the impacts of climate change will be spatially explicit. Projected rainfall reductions for 2030 showed marginal impact on hazardscapes with low seasonal reliabilities, primarily in winter and spring. The 2070 projections showed that some hazardscapes were unlikely to receive past rates of rainfall thus limiting the ongoing prospects of current and perhaps the potential adoption of alternative rain-fed land uses. Reductions in rainfall for hazardscapes with higher historical rainfall reliabilities will cause negative impacts on crop development. The ability to quantify the potential spatial and temporal impacts of climate change on seasonal trends will inform land managers' climate change mitigation and adaptation pathways. [Copyright &y& Elsevier]

Abstract: Land-cover change has significant impacts on regional carbon dynamics. Understanding the carbon consequences of land-cover change is necessary for decision makers to address the issues of carbon reduction and climate change mitigation. Optical remote sensing images have been widely used for detecting regional land-cover change. However, it is difficult to acquire desirable images for regions that are frequently affected by cloudy and rainy weather. In this study, we proposed an approach to deal with this problem by integrating moderate-resolution imaging spectroradiometer (MODIS) and Landsat images based on the mixed-label analysis (MLA) model. We tested this model in Guangdong Province, a fast developing sub-tropical region in China, to derive the provincial land-cover data for the analysis of land-cover change between 2000 and 2009 and its impacts on regional carbon dynamics. Results show that forest land decreased by 3.03%, while built-up area rapidly expanded by 73.01% from 2000 to 2009. The regional vegetation carbon sink declined by 2.6%, whereas the regional carbon emissions increased by more than 100% due to the fast urbanization and economic development. The regional vegetation carbon sink can only offset 4.1% of total carbon emissions in 2009, far below the national level (about 7.0–7.7%) at the same period. Future efforts to improve the regional carbon budget should focus more on the control of land development and the advance of energy efficiency. [Copyright &y& Elsevier]

Abstract: Federal political deadlock has long forced progressive climate change mitigation efforts in the United States to target greenhouse gas emissions and reduction options at regional, state, urban, and local levels. Even as a national mitigation agenda solidifies, researchers and political actors might strategically maintain local places and types of landscape – center cities, older and newer suburbs, and rural areas in different United States regions – as distinct spheres for analysis and action. This local articulation permits ongoing analysis of how place/landscape type-specific conditions structure everyday greenhouse gas emissions and the prospects for reducing them. As such, it promotes mitigation programs that encompass broad, long-term infrastructure and lifestyle transformations for energy efficiency and conservation; not only top-down changes to energy generation technologies. Participatory climate change mitigation research in the Philadelphia suburbs demonstrates how geographically particular metropolitan development patterns shape the prospects for two such policies, residential energy efficiency improvement and the promotion of local food systems. The sprawling suburb investigated here, with the center city its development has helped impoverish, challenges these mitigation options in particular and emissions reduction in general. Deeply problematic elements include both the landscape''s ever-extending physical morphology and the socioeconomic inequalities that this built environment – and the stakeholders who build it – help to create and maintain. Reshaping this and other suburban landscapes can not only promote long-term climate change mitigation but also reduce vulnerability to climate change''s unavoidable impacts. [Copyright &y& Elsevier]

Terrestrial carbon stock estimates information has significant importance in planning decisions for global warming and climate change mitigation. This study aimed to estimate and analyze carbon stock changes in Kenya as consequence of land cover change (LCC) using free open data to provide affordable and timely information. Using Random Forest (RF) decision trees, the land cover for 2028 was modelled based on 2004 and 2016 land cover under a Business as Usual (BAU) and an alternative Reducing of Emissions from Forest Degradation and Deforestation (REDD+) scenarios. The InVEST carbon model was used for estimation and valuation of carbon stock between 2004 and 2028. Results show a 16% decline in carbon stock with a loss of 21 billion US$ under the BAU scenario. On a regional scale, results show a gradual decline in carbon stock in the Coastal and Central regions while other regions exhibited mixed results. This trend can be reversed by the implementation of a REDD + scenario with a possible increase of 1.6% between 2016 and 2028, translating to a gain of 1 billion US$. This study contributes to the understanding of spatiotemporal carbon stock changes under different scenarios for effective spatial planning aiming to a balanced natural resource utilization. [Display omitted] • We estimate carbon stock changes in Kenya as consequence of LULC changes. • We compare business as usual with REDD + scenario using InVEST tool. • A REDD + scenario increases carbon stock in 1.6%–2028 while BAU declines 16%. • We provide a ready-to-use methodology for spatial implementation of REDD + policy. [ABSTRACT FROM AUTHOR]

Crassulacean Acid Metabolism (CAM) plants have the potential to provide future-proof biomass growth under increasingly stressed climatic conditions. Using active cultivation and anaerobic digestion, CAM plants can be grown and fermented to produce biogas or hydrolysed to extract valuable volatile fatty acids (VFAs) which can be applied to a range of uses: energy provision, protein and bioplastic production, carbon sequestration. However, an understanding of the spatial potential for CAM plants to be actively grown and harvested for bio-economic uses across Africa is unknown. A combined conservative assessment which incorporates three key dimensions is lacking from the literature: i) where can CAM plants physiologically grow? ii) where can CAM plants be cultivated without competing with existing land use? and iii) where lies the greatest energy demand? Answering these three questions and mapping the spatial variability between these aspects is essential to the future bioplastics/protein sector and opportunity to capitalise on generating sustainable energy which can connect off-grid rural and peri-urban communities whilst also achieving climate change mitigation targets. Using Opuntia ficus-indica as an example, this study compares two measures of land suitability estimation based on ecophysiological requirements and social, environmental and land-use masks. Focusing on abandoned land, conservative baseline estimates suggest that c.28–55 million hectares of land may be suitable for active CAM cultivation, with the potential to repurpose degraded lands and provide alternative bio-economic livelihoods to communities across semi-arid regions of Africa. [ABSTRACT FROM AUTHOR]

Urbanization is a pressing issue of concern especially in Africa where it is expected to continue and increasingly, threaten the efficiency of natural carbon sinks and sustainability of cities. This paper assessed the diversity and carbon storage of trees in Zaria metropolis, North-western Nigeria through fieldwork and allometric equations. A total of 200 assessment plots were randomly generated using Idrisi Terrset software. Quadrats of 30 × 30 m dimension were established and all trees, ≥5 cm diameter were identified and enumerated. Diameter was measured at breast height while tree height was measured with Suunto clinometer. The study recorded 836 stems, belonging to 51 species in 21 families. Species diversity and evenness were considerably high (H' = 3.30, J = 0.8) with more exotic than native stems. The trees stored 657.05t carbon with the highest proportion contributed by Azadirachta indica, Mangifera indica and Khaya senegalensis. One-way ANOVA revealed significant difference in tree diameter (p < 0.020), basal area (p < 0.008) and height (p < 0.001) across the different land use/cover types but no significant difference in carbon stock (p > 0.657). This study demonstrates the contribution of urban trees in reducing global atmospheric carbon which largely varies with tree species and diameter. • The dominant tree species in Zaria metropolis are exotic in origin while many native species are represented by few individuals. • The study highlights the importance of well-coordinated tree planting and management which focus on reintroducing, propagating and protecting the native species alongside the dominant, exotic ones. • Native tree species such as Khaya senegalensis, Parkia biglobosa and Adansonia digitata store considerable amount of AGC. • Effective climate change mitigation in the city could be achieved with careful selection of tree species with high carbon storage. [ABSTRACT FROM AUTHOR]