Net Land Research Articles

Low latency carbon budget analysis reveals a large decline of the land carbon sink in 2023

Abstract In 2023, the CO2 growth rate was 3.37 ± 0.11 ppm at Mauna Loa, 86% above the previous year, and hitting a record high since observations began in 1958, while global fossil fuel CO2 emissions only increased by 0.6 ± 0.5%. This implies an unprecedented weakening of land and ocean sinks, and raises the question of where and why this reduction happened. Here we show a global net land CO2 sink of 0.44 ± 0.21 GtC yr−1, the weakest since 2003. We used dynamic global vegetation models, satellites fire emissions, an atmospheric inversion based on OCO-2 measurements, and emulators of ocean biogeochemical and data driven models to deliver a fast-track carbon budget in 2023. Those models ensured consistency with previous carbon budgets. Regional flux anomalies from 2015–2022 are consistent between top-down and bottom-up approaches, with the largest abnormal carbon loss in the Amazon during the drought in the second half of 2023 (0.31 ± 0.19 GtC yr−1), extreme fire emissions of 0.58 ± 0.10 GtC yr−1 in Canada and a loss in South-East Asia (0.13 ± 0.12 GtC yr−1). Since 2015, land CO2 uptake north of 20°N declined by half to 1.13 ± 0.24 GtC yr−1 in 2023. Meanwhile, the tropics recovered from the 2015–16 El Niño carbon loss, gained carbon during the La Niña years (2020–2023), then switched to a carbon loss during the 2023 El Niño (0.56 ± 0.23 GtC yr−1). The ocean sink was stronger than normal in the equatorial eastern Pacific due to reduced upwelling from La Niña's retreat in early 2023 and the development of El Niño later. Land regions exposed to extreme heat in 2023 contributed a gross carbon loss of 1.73 GtC yr−1, indicating that record warming in 2023 had a strong negative impact on the capacity of terrestrial ecosystems to mitigate climate change.

Spatiotemporal dynamics of vegetation net primary productivity and its response to climate variability

Despite its significance, net primary productivity is rarely used as an indicator of climate change. The purpose of this study was to assess the spatiotemporal dynamics of vegetation net primary productivity and its response to climate variability in the Welmel watershed, southeastern Ethiopia. The investigation utilized data from the Moderate Resolution Imaging Spectroradiometer, and the Climate Hazards Group Infrared Precipitation with Stations accessed through the Google Earth Engine cloud computing platform. To evaluate the trend and response of net primary productivity to climatic factors, the Mann-Kendall and Theil Sen’s tests, the Pearson correlation coefficient, and stability analysis through the coefficient of variation of net primary productivity were utilized. The analysis of the temporal trend of net primary productivity revealed that the entire watershed, forest, wood, and cultivated land areas exhibited decreasing trends with net primary productivity values of -0.681, -4.361, -1.41, and − 3.25 g C m− 2/year, respectively. On the other hand, shrubs and grazing land displayed increasing trends of 1.15 and 2.04 g C m− 2/year, respectively. The wood and shrubland trends were statistically significant (p < 0.05). In the spatial analysis, an area of 64.6% showed a decreasing trend, whereas 33.78% displayed an increasing trend in net primary productivity values. The areas with stable and unstable variations in net primary productivity accounted for 26.47% and 8.02%, respectively. The net primary productivity of the land cover types and entire watershed were positively correlated with rainfall, however, only forests and woodlands were statistically significantly correlated (p < 0.05). The net primary productivity and land surface temperature were negatively correlated, except for forests and cultivated land, which were positively correlated. The results of this study provide essential information for managing ecosystems, supporting agricultural practices, and enhancing community resilience in a changing climate.

National introduction of no net land take: a comparative study of five pioneering countries seeking to limit their land consumption

The ambitious European objective of achieving no net land take (NNLT) by 2050 calls for a radical change in the strategies and instruments of national planning policies. Based on a comparative case study of five pioneering countries, this article analyses the different approaches taken to implement the NNLT goal, drawing on policy cycle theory. It demonstrates that the transfer of the NNLT target is a top-down process that conflicts with land use plans and planning practices at the local level. This research shows that the support and involvement of the local planning level is crucial to effectively reduce land use.

Carbon dioxide fertilization enhanced carbon sink offset by climate change and land use in Amazonia on a centennial scale

The Amazon, the Earth's largest tropical forest, plays a critical role in the global carbon cycle, acting as a significant carbon sink. Recent studies, however, indicate a decline in its carbon sequestration capacity due to climate variability, intensive deforestation, and fires. This study aims to examine the impacts of these factors on the carbon dynamics of the Amazon over a centennial scale based on dynamic global vegetation models (DGVMs) of Trendy-v11. It was found that the Amazon region exhibited significant spatiotemporal variations in net land carbon (C) fluxes, and was a net C sink (40.02 ± 242.64 Tg C yr−1) during 1901–2021. The Amazonian net biome productivity (NBP) showed a 6-decades-scale shift from a decreasing trend (−3.78 Tg C yr−2) during 1901–1959 to an increasing trend (2.39 Tg C yr−2) during 1960–2021. The Amazonian NBP was negatively related to air temperature while positively related to dry-season precipitation during 1901–2021. Furthermore, the increase of atmospheric CO2 concentration during 1901–2020 enhanced Amazonian NBP by 36.40 ± 8.39 Pg C, which was largely offset by land use change (−18.84 ± 12.02 Pg C) and climate change (−10.03 ± 5.00 Pg C). Our findings underscore the critical need for sustainable management practices in the Amazon to enhance its C sink and preserve its function in the global climate system.

Food insecurity and its determinants in pastoralist and agrarian communities in South Omo Zone, Southern Ethiopia: a community-based cross-sectional study.

Despite the implementation of different interventions, food insecurity remains a major public health issue in rural areas of Ethiopia. However, there has been limited evidence regarding food insecurity and responsible factors in rural areas of Ethiopia, particularly in South Omo, Ethiopia. Hence, this study aimed to assess food insecurity and determinants in agrarian and pastoralist communities of South Omo Zone, Southern Ethiopia. A cross-sectional study was done among 605 randomly selected households in Benatsemay and South Ari districts from February 1 to 28, 2023. A standardized and validated Household Food Insecurity Access Scale (HFIAS) was used to measure food insecurity status. Data were entered using Epi-Info 7.1 and then transferred to SPSS V25 for analysis. To identify associated factors, a binary logistic regression model was employed. The strength of association was evaluated considering the adjusted odds ratio (AOR) and a 95% confidence interval (CI). A statistical significance was stated at p-value <0.05. A total of 597 participants were involved in the study with a response rate of 98.7%. The overall prevalence of food insecurity using HFIAS was 42.2% (95%CI: 38.2, 46.3%), among which mild, moderate, and severe food insecurity accounted for 17.4, 16.6, and 8.2%, respectively. Of pastoralists, 114 (47.1%) were food insecure whereas 138 (38.9%) were food insecure in the agrarian. Food insecurity was affected by household head sex (AOR = 1.73, 95%CI: 1.14, 2.62), high dependency ratio (AOR = 2.53, 95%CI: 1.53, 4.20), no formal maternal education (AOR = 2.11, 95%CI: 1.07, 4.18), productive safety net program (AOR = 2.00, 95%CI: 1.16, 3.46) and land ownership (AOR = 1.80, 95% CI: 1.19, 2.72). Food insecurity was a significant problem in the study areas. Thus, it is crucial to improve female education, advance agricultural technologies, advocate family planning, and broaden productive safety net programs.

Toward understanding the hydrologic, ecologic and community flooding implications of coastal restoration strategies: Sediment diversions

Evaluating the real-world impacts of proposed restoration strategies is a complex process. Typically, restoration is pursued to achieve a number of primary and secondary objectives as most coastal and deltaic areas support a variety of functions and activities with substantial social and economic values. In this analysis, we demonstrate the importance of considering the broad implications of planning and implementing restoration projects. We use a recently developed simplified and computationally efficient biophysical numerical model. The Mid-Barataria Sediment Diversion, a restoration project approximately 60 km down the Mississippi River from New Orleans, Louisiana, USA, offers an opportunity to quantify the benefits and potential impacts of large-scale restoration. Operation plans of the diversion are employed in this analysis to reveal the delicate balance between its potential benefits and possible adverse effects. Evaluation metrics include net land change and landscape evolution, change in salinity and subsequent shift in the distribution of marsh types, long-term change in the hydroperiod and marsh inundation, and change in the flood risk for unique local coastal communities and culture. We also consider subaqueous basin infilling, spatial sediment deposition, and creation of shallow water areas that might be of ecological value. These metrics are evaluated collectively under a set of future scenarios capturing long-term impacts of sea level rise and subsidence. This analysis provides evidence in favor of using a multi-metric approach to holistically evaluate restoration during the planning and design phases, as well as to guide the process of adaptively managing restoration projects post construction.

Bird Phylogenetic Diversity Increases With Temperature Worldwide

ABSTRACTAimTemperature significantly influences the composition and structure of biotic communities at large scales. While its role in shaping taxonomic diversity is well‐documented, its relationship with other facets of biodiversity, like phylogenetic diversity, remains poorly known. Understanding how and to which extent temperature contributes to global patterns of phylogenetic diversity compared to other biodiversity‐structuring factors is crucial for comprehending how bird assemblages are structured worldwide, predicting their response to global‐change drivers and supporting conservation policies focused on preserving bird genetic diversity and evolutionary history.LocationWorldwide.MethodsWe analyse the role of temperature in predicting bird regional phylogenetic richness (PD) and divergence (MPD) worldwide, before and after controlling for the effect of species richness (SR). We also assess the shape of this relationship in different biogeographic realms and compare its explanatory power with other key biodiversity‐structuring factors such as elevation, human impact index, net primary productivity and land use diversity.ResultsOur findings underscore the high significance and consistency of temperature as a key predictor positively associated with bird PD and MPD across the six main biogeographic realms, even after accounting for SR and latitude, suggesting that temperature modulates the intrinsic capacity of environments to support a diverse array of lineages. In addition, PD and MPD tended to increase at low elevations, but the human‐impact index did not effectively predict bird phylogenetic diversity at this scale. Furthermore, high PD was linked to regions with high primary productivity and high land‐use diversity, although both of these relationships were strongly mediated by SR.ConclusionsThis study unveils the key role of temperature in explaining bird phylogenetic diversity worldwide over other key biodiversity‐structuring factors and points to the profound implications that climate change will have on the amount of evolutionary history held in bird assemblages, beyond species extinctions or range shifts alone.

Green buffer areas and green roofs: performance design to improve the urban water cycle

Abstract While in all Europe the land use does not decrease – contrary to EU soil strategy that would actualize the zero net land use by 2050 – cities are plagued by problems such as air pollution, urban heat island effect and uncontrolled run-off following intense rain events, which degrade the environment threatening the health and the safety of inhabitants. The impermeable materials and are responsible for the worsening of the urban water cycle and, at the same time, for the increase in summer air temperatures: both those effects can be mitigated by nature-based and draining solutions. The paper explains the hydrological phenomena of the urban impervious surfaces, highlighting the typical functional defects, providing then a list of various green technologies suitable to overcome the common issues of city centers like high density / reduced spaces, irreversible impervious surfaces, undersized drainage, presence of sub-structures / sub-systems, conservation of architectural heritage. The technical green solutions on the ground (bio-retention systems, rain gardens, trees, pervious pavements…) and on the roofs, specifically designed, behave 1) as a buffer for the stormwater and superficial run-off, being able to collect water, 2) as providers of side effects that can affect water quality, biodiversity, amenity in cities. Experimental results from a rain simulation are presented in order to argue potentials and limitations of these solutions, often narrated as salvific, or, on the contrary, underestimated in their technological specificities.

Towards a more realistic estimation of urban land take by combining cadastral parcels and building footprints

Despite its importance as a research issue, a widely accepted methodology of estimating land take resulting from urbanization has not yet been reached. Accurate geospatial datasets are currently available at a European and global level; however, different methods of quantifying urban land take could lead to diverse outputs, potentially resulting in underestimation. This can be alarming as encroaching urban sprawl is emerging as a major environmental challenge by destroying natural habitats, consuming productive agricultural land, and contributing to climate change by increasing energy demands. To address this knowledge gap, we propose an estimation of urban land take that combines cadastral parcels and building footprints. Land parcels can be considered as a suitable minimum mapping unit as they are directly related to the spatial level where economic decisions on land use conversion are made. The proposed geospatial method is compared to methods that depend on datasets of High Resolution Layer Imperviousness, Global Building Footprints (alone), Corine Land Cover, Urban Atlas, and Global Human Settlement Layer. The method is exemplified in case studies in Greece, specifically: (a) two islands of the South Aegean Region (Mykonos and Thera), that are heavily impacted by tourism development and sprawl and (b) a peri-urban zone (Thermaikos-Michaniona) within the metropolitan area of Thessaloniki, impacted by intense suburbanization. Results show that urban land consumes important shares of available land since the mid-20th century, this fact highlighting the dynamic encroachment of urban development. Calculation shows that other methods could underestimate urbanized areas by up to 80%–90%. In the discussion section, the advantages of shifting the focus from the pixel to the parcel are further justified, while explicit links to spatial planning policies for sprawl containment are drawn. Such policies could be informed by more realistic estimations of urban land take, in order to proceed with strategic and regulatory measures to support the ‘no net land take’ policy of Europe.

A consistent budgeting of terrestrial carbon fluxes

Accurate estimates of CO2 emissions from anthropogenic land-use change (ELUC) and of the natural terrestrial CO2 sink (SLAND) are crucial to precisely know how much CO2 can still be emitted to meet the goals of the Paris Agreement. In current carbon budgets, ELUC and SLAND stem from two model families that differ in how CO2 fluxes are attributed to environmental and land-use changes, making their estimates conceptually inconsistent. Here we provide consistent estimates of ELUC and SLAND by integrating environmental effects on land carbon into a spatially explicit bookkeeping model. We find that state-of-the-art process-based models overestimate SLAND by 23% (min: 8%, max: 33%) in 2012–2021, as they include hypothetical sinks that in reality are lost through historical ecosystem degradation. Additionally, ELUC increases by 14% (8%, 23%) in 2012–2021 when considering environmental effects. Altogether, we find a weaker net land sink, which makes reaching carbon neutrality even more ambitious. These results highlight that a consistent estimation of terrestrial carbon fluxes is essential to assess the progress of net-zero emission commitments and the remaining carbon budget.

Spatial Mapping and Prediction of Groundwater Quality Using Ensemble Learning Models and SHapley Additive exPlanations with Spatial Uncertainty Analysis

The spatial mapping and prediction of groundwater quality (GWQ) is important for sustainable groundwater management, but several research gaps remain unexplored, including the inaccuracy of spatial interpolation, limited consideration of the geological environment and human activity effects, limitation to specific pollutants, and unsystematic indicator selection. This study utilized the entropy-weighted water quality index (EWQI), the LightGBM model, the pressure-state-response (PSR) framework and SHapley Additive exPlanations (SHAP) analysis to address the above research gaps. The normalized importance (NI) shows that NO3− (0.208), Mg2+ (0.143), SO42− (0.110), Cr6+ (0.109) and Na+ (0.095) should be prioritized as parameters for remediation, and the skewness EWQI distribution indicates that although most sampled locations have acceptable GWQ, a few areas suffer from severely poor GWQ. The PSR framework identifies 13 indicators from geological environments and human activities for the SMP of GWQ. Despite high AUROCs (0.9074, 0.8981, 0.8885, 0.9043) across four random training and testing sets, it was surprising that significant spatial uncertainty was observed, with Pearson correlation coefficients (PCCs) from 0.5365 to 0.8066. We addressed this issue by using the spatial-grid average probabilities of four maps. Additionally, population and nighttime light are key indicators, while net recharge, land use and cover (LULC), and the degree of urbanization have the lowest importance. SHAP analysis highlights both positive and negative impacts of human activities on GWQ, identifying point-source pollution as the main cause of the poor GWQ in the study area. Due to the limited research on this field, future studies should focus on six key aspects: multi-method GWQ assessment, quantitative relationships between indicators and GWQ, comparisons of various spatial mapping and prediction models, the application of the PSR framework for indicator selection, the development of methods to reduce spatial uncertainty, and the use of explainable machine learning techniques in groundwater management.

Development and application of a simplified biophysical model to study deltaic and coastal ecosystems

Many coastal regions around the globe experience land loss due to high relative sea level rise rates, declining sediment supply, and a host of other anthropogenic factors. To evaluate possible restoration strategies, we developed a computationally efficient Simplified Biophysical Model (SBM). The SBM includes hydrodynamic, morphodynamic, and marsh inundation components. The hydrodynamic and mineral sediment processes of the SBM are based on open source Delft3D models. The marsh inundation MATLAB module is a simplified vegetation response to salinity and inundation used to estimate annual organic accretion rates. Organic accretion is added annually to the morphodynamic calculations of mineral sediment. The typical run time for the SBM for an area of 4500 km2 is ∼0.8, 2.5, and 4.7 days real time for one, three, and five decade simulations, respectively which is considered a computationally efficient for modeling decadal landscape evolution. The utility of the SBM was demonstrated through an application to assess the performance of a sediment diversion in the Barataria Basin in Louisiana, USA. The model results demonstrate the importance of incorporating the impact of salinity and inundation effects on the resilience of marshes subjected to high rates of relative sea level rise. Further, the sediment reduction analysis confirms the critical impact of the Mississippi River sediment decline on potential land building from sediment diversions where 1.5%, and 3% annual declining rates show a reduction in net land gain due to Mid-Barataria Sediment Diversion operation of 30% and 50 %, respectively. This highlights the importance of considering the Mississippi River sediment supply decline in restoration projects’ planning and specifically, sediment diversions.

Long-Term Seasonal and Annual Rainfall Trend Analysis of Giridih District, Jharkhand, India

District Giridih is primarily rain dependent on its 95 per cent net cultivable land under summer-monsoon crops. It is classified as a mono-cropping area as it lacks irrigation facilities, essential for winter crops. In the last few years, the district experienced water stress due to the shortage of monsoon rainfall. We study long term seasonal and annual rainfall trend analyses for the Giridih district of Jharkhand in India using linear regression modelling. The last 100 years of data were taken for the study and were divided into two-time phases of 50 years each to analyse the changing pattern of rainfall trends. We found a decreasing trend in monsoon rainfall from 1 mm y-1 to 3 mm y-1 between the initial (1921-1971) and final (1972-2021) phase of the study period. Similarly, the return period of droughts (rainfall deficit years) has also reduced from 11 years to 5 years. The study has shown that the rainfall pattern has changed, with the winter months showing a decrease and the pre-monsoon months an increase in their relative contributions to the annual rainfalls. The study may help in the formulation of water resource conservation-oriented decision-making to cope-up with the rainfall uncertainties and meet the future water demand.

The impacts of modelling prescribed vs. dynamic land cover in a high-CO2 future scenario – greening of the Arctic and Amazonian dieback

Abstract. Terrestrial biosphere models are a key tool in investigating the role played by land surface in the global climate system. However, few models simulate the geographic distribution of biomes dynamically, opting instead to prescribe them using remote sensing products. While prescribing land cover still allows for the simulation of the impacts of climate change on vegetation growth and the impacts of land use change, it prevents the simulation of climate-change-driven biome shifts, with implications for the projection of future terrestrial carbon sink. Here, we isolate the impacts of prescribed vs. dynamic land cover implementations in a terrestrial biosphere model. We first introduce a new framework for evaluating dynamic land cover (i.e., the spatial distribution of plant functional types across the land surface), which can be applied across terrestrial biosphere models alongside standard benchmarking of energy, water, and carbon cycle variables in model intercomparison projects. After validating simulated land cover, we then show that the simulated terrestrial carbon sink differs significantly between simulations with dynamic vs. prescribed land cover for a high-CO2 future scenario. This is because of important range shifts that are only simulated when dynamic land cover is implemented: tree expansion into the Arctic and Amazonian transition from forest to grassland. In particular, the projected change in net land–atmosphere CO2 flux at the end of the 21st century is twice as large in simulations with dynamic land cover than in simulations with prescribed land cover. Our results illustrate the importance of climate-change-driven biome shifts for projecting future terrestrial carbon sink.

Sedimentary record of water-sediment regulation and channel shifts in the Yellow River (Huanghe) Delta

Delta are vital habitats for people and biotic communities. Many of the world's large river deltas are shrinking because of relative sea level rise and intensifying human interventions in the basin. Among these, the Yellow River Delta (hereafter YRD) has been enormously impacted by frequent channel avulsions and a Water-Sediment Regulation Scheme (WSRS) through upstream reservoirs since 2002. However, it remains undisclosed how the YRD responses to these human interventions. Here, modern sedimentation and inter-annual to multi-decadal timescales evolution of the YRD were studied using a dataset including 10 sediment cores collected in the subaqueous delta during the 2014 WSRS, satellite images, hydrographic and bathymetric data from 1976 to 2014. Our results show that the sedimentation of the delta can be divided into three stages: 1976–1995, 1996–2001, and 2002–2014. The area of subaerial delta generally increased from 3884 km2 to 4441 km2 during the whole 1976–2014 period except for a net land loss during 1996–2000. >70% of the delta coastline became artificial after 2000. Bathymetric data reveals that the subaqueous delta was seriously eroded after 1996 due to a shortage of sediment supply, with an estimated 2.3 × 108 t/yr and 1.1 × 108 t/yr of sediment respectively transported to the delta's adjacent sea during 1996–2001 and 2002–2014. The deltaic sediment became coarser due to the impact of the WSRS. Radionuclide 7Be uncovers a rapid sediment accumulation of ∼12 cm at the active delta front during the 2014 WSRS. The evolution of the YRD has become complex under the influence of natural and anthropogenic factors. The YRD thus provides an exemplar shift from natural to human-dominated delta. These results are important for the delta management decision making.

Legislative Foundations: Exploring Land Take Laws and Urban Regeneration Policies in Italy and Europe

Soil is now a central issue on the European as well as the national political agenda, as it represents a fundamental ecosystem for human survival on the planet. Today, more than ever, its protection and proper use in various contexts (agricultural, natural, urban) require stringent policies that can be implemented immediately. The difficult reversibility of urban transformations is the main threat to the ecosystem integrity of soil. Starting from this statement, the main objective of the proposed work is to analyze how the main European countries (Italy, France, Germany, and Spain) are addressing the issue of the goal of zero net land take by 2050 by examining the current laws and strategies. The results highlight how the regulatory aspect plays a key role in managing the phenomenon and how the absence of a national framework law can generate strong distortions and different interpretations of the soil ecosystem. The analysis of the Nature Restoration Law, adopted by the European Commission in July 2023, enables us to assess whether the regulations and measures adopted by the major European countries align with the European Union’s trends. Through a comparative perspective, the study aims to contribute to a comprehensive understanding of sustainable development practices and provide valuable insights for policymakers, urban planners, and academics.

Exploring the implications of ‘no net land take’ policy for spatial planning: the case of the Netherlands

The European Union’s ‘no net land take’ (NNLT) target, which seeks to halt greenfield development by 2050, is very pertinent for planners. The present article investigates its potential impact with special attention for the Netherlands. Given that no single definition or methodology had been established at the EU level, land take was calculated over the 2000–2018 period for alternative definitions. A result is that qualitative approaches oriented to soil quality provide more scope for flexibility than quantitative approaches oriented towards land use. In addition, successful implementation of NNLT will depend on engaging with planners and planning practice.

Spatiotemporal analysis of shoreline change trends and adaptation in Bali Province, Indonesia

Shoreline change is a dynamic and complex phenomenon influenced by various natural and anthropogenic factors. Monitoring these changes is crucial for understanding coastal dynamics, managing resources, and mitigating the impacts of coastal erosion and accretion. Remote sensing plays a vital role in monitoring shoreline change. This technology has emerged as a powerful tool for accessing and monitoring shoreline changes due to its ability to capture large-scale spatial data over different periods. This study investigated the dynamic changes in shoreline position in Bali Province from 2016 to 2021 using high-resolution PlanetScope imagery data. Multitemporal shorelines were extracted using the Normalized Difference Water Index (NDWI) to delineate seawater from distinct land-cover types. The end point rate (EPR) model was then used to statistically quantify the shoreline change rates. The results revealed variations in the positions of the shorelines throughout the study, with rapid erosion emerging as a major concern in Bali Province, primarily driven by human activities and/or coastal hydrodynamics. During the study period, the shoreline in Bali Province decreased from 668.64 km to 662.59 km at an average rate of -1.21 m/yr due to continuous erosion, with the most significant retreat occurring at Klungkung Regency. On the other hand, human-caused shoreline advancement, such as land reclamation, harbor, and airport construction, has resulted in a net land increase of 1.25 km2. The protection strategies include structural interventions such as breakwaters and seawalls. The finding provides valuable information that will be helpful for coastal planning and management to reduce the loss of the economy and safeguard the future coastal environment in Bali’s coastal areas.

Trajectories of urban land consumption along the urban-rural gradient in France, 1975–2020

ABSTRACT Urban land consumption negatively impacts ecosystem services such as food production, carbon regulation, and water absorption. Despite indications of densification in some large cities, evidence shows that built-up land has been increasing faster than population globally. However, existing research disproportionally focuses on large cities, overlooking intermediate and rural territories. Our study examines the trajectories of urban land consumption along the urban-rural gradient in France between 1975 and 2020. We quantify built-up land per capita (BPC) and the changes therein and compare it to a 7-level classification of territories according to their density. BPC increased 59%, combining a 95% increase in built-up land and a 23% population growth. Yet, BPC change varied considerably across the seven territory classes: very scattered rural areas experienced the largest growth (+190 m2) while large cities grew more efficiently (+11 m2). Intermediate territories, such as peri-urban areas and small cities, increased BPC by 65% and 78%, respectively. Our findings confirm the hypothesis of urban land use polarization, as rural areas were sparser than large cities in the base year, and this difference increased over time. This underlines the urgency to address the distinct land use trajectories for effective no net land take policies.

The Second-Round Effects of the Agriculture Value Chain on Farmers’ Land Transfer-In: Evidence from the 2019 Land Economy Survey Data of Eleven Provinces in China

In the context of the separation of three rights of land and agricultural modernization, this paper is based on the land economic survey data from eleven provinces in China in 2019, covering the eastern, middle, and western regions of China. Based on the value chain theory and its “second-round effect”, which pertains to the multi-round effects of value chain distribution theory, various research methods such as Probit, Tobit, the two-part model, SFA, PSM, and the intermediary effect model are employed to analyze the direct impact of the agriculture value chain (AVC) on farmers’ land factor inputs and the income effects caused by them, which are the “second-round effect” of the AVC on land factor inputs. The research results show the following: Firstly, the AVC has a significant positive impact on the behavior and area of farmers’ land transferring-in, which helps guide farmers towards large-scale land operation. Secondly, the AVC significantly improves farmers’ production efficiency and promotes land transfer through differences in production efficiency, representing the “second-round effect” mechanism of the AVC on land factor inputs. Moreover, the AVC will increase farmers’ net land production income by 48.74%, which is the “second-round effect” of the AVC on farmers’ agricultural income and also the motivation for farmers’ land factor inputs. Finally, the expansion of land area and the improvement of production efficiency jointly increase farmers’ agricultural income, among which production efficiency plays a partial intermediary effect in increasing agricultural income if farmers join the AVC. This paper believes that we should further promote the market-oriented reform of land factors, support the innovation of the benefit linkage mechanism of the AVC, and promote appropriate areas of land operation by farmers, thereby achieving common prosperity and promoting agricultural modernization in China.