Innovations through crop switching happen on the diverse margins of US agriculture.

Crop switching, in which farmers grow a crop that is novel to a given field, can help agricultural systems adapt to changing environmental, cultural, and market forces. Yet while regional crop production trends receive significant attention, relatively little is known about the local-scale crop switching that underlies these macrotrends. We characterized local crop-switching patterns across the United States using the US Department of Agriculture (USDA) Cropland Data Layer, an annual time series of high resolution (30 m pixel size) remote-sensed cropland data from 2008 to 2022. We found that at multiple spatial scales, crop switching was most common in sparsely cultivated landscapes and in landscapes with high crop diversity, whereas it was low in homogeneous, highly agricultural areas such as the Midwestern corn belt, suggesting a number of potential social and economic mechanisms influencing farmers' crop choices. Crop-switching rates were high overall, occurring on more than 6% of all US cropland in the average year. Applying a framework that classified crop switches based on their temporal novelty (crop introduction versus discontinuation), spatial novelty (locally divergent versus convergent switching), and categorical novelty (transformative versus incremental switching), we found distinct spatial patterns for these three novelty dimensions, indicating a dynamic and multifaceted set of cropping changes across US farms. Collectively, these results suggest that innovation through crop switching is playing out very differently in various parts of the country, with potentially significant implications for the resilience of agricultural systems to changes in climate and other systemic trends.

Reclamation alters evapotranspiration and its biophysical controls in a meadow grassland on the Mongolian Plateau.

Global grasslands were constantly being replaced and reclaimed for cropland, and such reclamations may profoundly affect ecological such as water cycles. However, the long-term effects of this conversion on evapotranspiration (ET) processes remain underexplored. To discern changes in ET from grassland to reclaimed cropland and among different crop rotations, a four-year study (2018-2021) was conducted using the eddy covariance system in a Hulunber grassland and a neighboring reclaimed cropland. The ET in reclaimed cropland (248 mm) was 49% higher than the grassland (166 mm) during the growing season (crop growth period), whereas the ET in the grassland (134 mm) exceeded that in the cropland (128 mm) by 6% in the non-growing season. The croplands experienced a 19% increase in precipitation, primarily due to artificial irrigation during the growing season. Meanwhile, the increase in ET in reclaimed cropland might also be influenced by changes in vegetation type and crop growth characteristics, as well as by rational tillage practices that increase the cover of vegetation and biomass. Notably, potato cultivation most closely matched the water balance of grasslands. In addition, irrigation directly increased soil water content (SWC), and that enhancing the sensitivity of ET to SWC. Overall, this study highlighted the importance of understanding ET variations due to grassland conversion to cropland and different crop rotations, emphasizing the role of irrigation and tillage practices.

Soil carbon pools and microbial network stability depletion associated with wetland conversion into aquaculture ponds in Southeast China.

Wetlands, which are ecosystems with the highest soil surface carbon density, have been severely degraded and replaced by artificial reclamation for fish and shrimp ponds in recent years. This transformation is causing intricate shifts in soil carbon pools and microbial stability. In this study, we examined natural wetlands and reclaimed aquaculture ponds in Southeast China to analyze the structure and network stability of soil microbial communities following the reclamation of estuarine wetlands and to elucidate the microbial-mediated mechanisms for regulating soil organic carbon (SOC). The aquaculture ponds presented significantly less average SOC content than the natural wetlands (p < 0.05). ACE, Chao1, and Shannon's indices of bacteria and fungi were decreased in aquaculture ponds. Less numbers of nodes and edge links in the co-occurrence network of soil fungi and bacteria in aquaculture ponds. This suggests reduced correlation and stability within the microbial network of aquaculture ponds. Decomposers in soil fungi (e.g. Dung Saprotroph) reduced. Reduced proportions of key phyla Ascomycota, Basidiomycota and Rozellomycota in the soil fungal network. Reduced proportions of key phyla Proteobacteria, Chloroflexi and Desulfobacterota in the soil bacterial network. In conclusion, our results suggest that converting wetland paddocks to intensive aquaculture ponds results in carbon pool loss and reduces soil microbial network stability. The results highlight the importance of protecting or moderately restoring mangrove wetlands along the coast of southeastern China. It is also predicted that such measures may enhance the storage capacity of soil carbon pools and improve the stability of carbon sequestration by soil microorganisms, thus offering a potential solution for mitigating global climate change.

Wildlife corridors in a Southern African conservation landscape: the political ecology of multispecies mobilities along the arteries of anthropogenic conservation.

The decline of biodiversity is a key topic in public discussions around the globe. These debates have triggered massive efforts to increase protected areas and to safeguard the corridors connecting them. The wildlife corridors dealt with in this article are mainly thought to facilitate the mobility of elephants and some other large herbivores (for example, zebra and buffalo). Wildlife corridors are not only essential for species connectivity but also an integral part of the booming ecotourism in north-eastern Namibia's conservation landscapes. Coexistence infrastructure is meant to contribute to economic development and local incomes. Conservancies - community-based conservation organisations in the Namibian context - gazette corridors and market wildlife abundance to ecotourists, potential investors in tourism and commercial hunters. The coexistence of humans and wildlife is challenging, though. Human-wildlife interactions frequently result in damage, and often conservationist environmental infrastructuring runs against the aims of farmers to expand their fields for commercial crop production and to gain pastures for growing cattle herds. It also runs against other governmentally endorsed infrastructuring that brings tarred roads, water pipelines and boreholes. This article analyses contested wildlife corridors as part of a larger conservationist project in the western parts of Namibia's Zambezi Region.

O declínio da biodiversidade é uma questão chave em discussões públicas em todo o mundo. Estes debates desencadearam esforços massivos para aumentar as áreas protegidas e para salvaguardar os corredores que as conectam. Os corredores de vida selvagem tratados neste artigo são pensados principalmente para facilitar a mobilidade de elefantes e de alguns outros grandes herbívoros (por exemplo, zebras e búfalos). Os corredores de vida selvagem não são apenas essenciais para a conexão das espécies, mas também como uma parte integrante do ecoturismo em expansão nas paisagens de conservação do nordeste da Namíbia. A infraestrutura de coexistência destina-se a contribuir para o desenvolvimento econômico e para os rendimentos locais. As conservações ­ organizações de conservação de base comunitária no contexto da Namíbia ­ anunciam os corredores e comercializam a abundância da vida selvagem para ecoturistas, potenciais investidores no turismo e caçadores comerciais. Contudo, a coexistência de humanos e vida selvagem é desafiadora. As interações entre os humanos e a vida selvagem frequentemente resultam em danos, e muitas vezes a infraestrutura ambiental conservacionista vai contra os objetivos dos fazendeiros de expandir suas terras para a produção agrícola comercial e de obter pastagens para os crescentes rebanhos de gado. Também vai contra outros projetos de infraestrutura apoiados pelo governo que trazem estradas asfaltadas, tubulações de água e poços. Este artigo analisa os controversos corredores de vida selvagem como parte de um projeto conservacionista mais amplo nas partes ocidentais da região do Zambeze na Namíbia.

Modelling the drivers of land use and land cover change of the great Amanzule wetland ecosystem to inform the development policy of the southwestern oil-rich region of Ghana.

This study focused on the current and future drivers of land-use change and its impact on the Amanzule wetland. It suggests policy implications for reviewing and strengthening existing policies for sustainable land use. This study employed remote sensing and GIS techniques, including participatory rural appraisal techniques. The administration of questionnaires and focus group discussions were conducted in the Ellembelle and Jomoro municipalities, where the Amanzule wetland provides economic and social services. The results showed increased land use over the last 32 years driven by various drivers, including food crop production, rubber plantations, oil and gas establishments, and infrastructure development. The study further revealed that these drivers could influence land-use change in 18 years (2018-2036). Urbanisation, cropland, rubber plantations, and shrubland will drive land-use change in the study area between 2036 and 2054. The Amanzule wetland area is expected to decrease from 272.34 ha in 2018 to 210.60 ha by 2036. The wetland area is expected to further decrease from 210.60 ha in 2036 to 174.33 ha by 2054. Other land use classes, such as mangrove and swamp forests, are also expected to decrease within the same period. The study recommends advocating for a wetland policy, enforcing the Land Use and Spatial Planning Act 925 and the Petroleum Exploration and Production Act 919 for sustainable development.

Global suitability and spatial overlap of land-based climate mitigation strategies.

Land-based mitigation strategies (LBMS) are critical to reducing climate change and will require large areas for their implementation. Yet few studies have considered how and where LBMS either compete for land or could be deployed jointly across the Earth's surface. To assess the opportunity costs of scaling up LBMS, we derived high-resolution estimates of the land suitable for 19 different LBMS, including ecosystem maintenance, ecosystem restoration, carbon-smart agricultural and forestry management, and converting land to novel states. Each 1 km resolution map was derived using the Earth's current geographic and biophysical features without socioeconomic constraints. By overlaying these maps, we estimated 8.56 billion hectares theoretically suitable for LBMS across the Earth. This includes 5.20 Bha where only one of the studied strategies is suitable, typically the strategy that involves maintaining the current ecosystem and the carbon it stores. The other 3.36 Bha is suitable for more than one LBMS, framing the choices society has among which LBMS to implement. The majority of these regions of overlapping LBMS include strategies that conflict with one another, such as the conflict between better management of existing land cover types and restoration-based strategies such as reforestation. At the same time, we identified several agricultural management LBMS that were geographically compatible over large areas, including for example, enhanced chemical weathering and improved plantation rotations. Our analysis presents local stakeholders, communities, and governments with the range of LBMS options, and the opportunity costs associated with scaling up any given LBMS to reduce global climate change.

Quantitative assessment of the key drives shaping the long-term dynamics of geographically isolated wetlands: A case study within the Nenjiang River Basin, Northeast China.

Geographically isolated wetlands (GIWs) offer a diverse array of ecosystem services and contribute largely to landscape functions. Numerous studies have documented the substantial pressures on wetland ecosystems from both natural changes and human activities worldwide. However, the quantification of these impacts on GIWs remains scarce. This study presents an assessment of the spatiotemporal dynamics of GIWs in the downstream portion of the Nenjiang River Basin, Northeast China, over a 38-year period (1978-2015). We quantitatively evaluated the impacts of anthropogenic activities and natural changes using a five-stage wetland dataset (1978, 1990, 2000, 2008, and 2015) and four-stage (1990, 2000, 2010, and 2015) land use datasets. Our findings indicate that 86% of the GIWs in the study area have vanished, primarily replaced by unused land (28.39%) and farmland (54.90%). Anthropogenic activities were identified as the main cause of wetland loss from 1978 to 2008, whereas natural changes have played a more significant role in recent years of GIWs. Considering the ongoing regional trends of warming and drying, it is imperative to conserve and restore GIWs to maintain their ecosystem services for a broad spectrum of beneficiaries.

[A Method for Fine Mapping of Carbon Emissions from Regional Land Use Change and Its Application].

Land use changes are always patchy and widespread within a region, making it a challenge to identify the point-scale pressure of reducing carbon emissions from land use/cover change （LUCC）. The carbon emission observation index （CEOI） was thus proposed to conduct the point-scale comparability analysis, which was based on the unique net C flux effects of conversions between two different land use types. Then, the spatial-temporal characteristics of land use changes and the resulting pressure of reducing carbon emissions were studied in the Weihe River Basin of China, which adopted the LUCC data from 2000 to 2020 and models of the Markov transition matrix （MTM）, compound carbon emission coefficients （CEC） of various types of land use changes, and the CEOI-based classification method on point-scale pressure of reducing carbon emissions. The results showed that： ① The net C flux was from 3.551 Tg C （2000-2010） to 7.031 Tg C （2010-2020）, and the pressure of reducing carbon emissions from LUCC had been continuously increasing, which was mainly driven by the significant increase in change-spots with the super-strong ability to reduce carbon emissions. ② Due to contributions from change spots with carbon uptake ability, the amount of carbon released to the atmosphere was eliminated by approximately 19.21% over the period 2000-2020 and approximately 37.4% during 2000-2010. ③ Change spots on various pressure levels for reducing carbon emissions were distributed unevenly in the basin, with their gravity points in the previous 10 years （2010-2020） far away from those during 2000-2010. Additionally, the gravity points of change-spots with a strong ability to reduce carbon emissions from conversions of grassland into forestland moved northeastward from Tianshui City to Pingliang City, whereas the gravity points of other change-spots with different abilities to reduce carbon emissions were mostly northwestward to the north-central region with higher elevations from the Middle and Lower Reaches of the Weihe River Basin with low elevations.

Quantifying future carbon emissions uncertainties under stochastic modeling and Monte Carlo simulation: Insights for environmental policy consideration for the Belt and Road Initiative Region.

This study critically examines future carbon (CO2) emissions in the Belt & Road Initiative (BRI) region, considering factors such as energy consumption, economic growth, population growth, and population density. The objective of this study is to identify critical areas of higher emissions, which require policy intervention capable of strengthening sustainability in the BRI compact. A combined approach of stochastic modeling and Monte Carlo simulations was employed, utilizing panel data from 45 countries in the BRI region from 1990 to 2021. Results confirm that emissions are higher in all scenarios in direct proportion to electric power consumption, population growth, and Gross Domestic Product (GDP) growth. In scenarios with high emissions, a continuous and significant upward trend in CO2 emissions was observe. The medium emissions scenario exhibited a more moderated rise in emissions, suggesting a balance between economic development and environmental considerations. Critical areas for future environmental policy-making resides in electric power consumption, population growth, and GDP growth. The study strongly recommends for a shift from the current focus on road and railway infrastructure to renewable energy infrastructure, green innovations and efficient technology transfer to member countries. Without this, the BRI region is likely to face increased emissions, posing significant challenges to future sustainable development and global environmental sustainability.

Root traits drive the recovery of soil nematodes during restoration of open mines in a tropical rainforest.

Mining is a major threat to vegetation and soil in the tropical forests. Reforestation of degraded surface mines is critically dependent on the recovery of soil health, where the nematodes play an important role. However, the key determinants of community assembly of soil nematodes during mine-restoration remain unknown in the tropical rainforests. Here, the recovery of taxonomic diversity of nematode communities and their trophic groups during reforestation of an extremely degraded tropical open-mining area is studied. The factors that may impact their recovery, such as root traits (length, area and tissue density), soil properties (pH and soil organic matter content (SOM)), and taxonomic diversities of soil bacterial and fungal communities are investigated. Differences in these parameters were evaluated in the three soil types: (i) mined soil - the erstwhile soil that was removed during mining and stock-piled for 10 years at the foot of an extremely degraded open-mining area; (ii) reforested soil, sampled from a 10-year successful restoration, which used the mined soil for reforestation; and (iii) undisturbed soil, collected from an adjacent undisturbed/not-mined tropical rainforest. A total of 11, 34 and 29 nematode-genera were identified in mined-, undisturbed-, and reforested soils, respectively. The taxonomic diversities of the 5 nematode groups in the mined soil were 1.5-5.2 times lower than in the undisturbed soil, but were similar in the restored and undisturbed soils. Taxonomic diversities of phytophagous and predator nematodes were correlated to restored root traits; whereas of bacterivores, fungivores, and omnivores were correlated to pH, SOM, soil bacterial and fungal communities. Consequently, complete loss of roots during mining likely severely reduced the nematodes, but their recovery after reforestation led to the restoration of taxonomic diversity of nematode communities. The mix-planting fast-growing tree species may be appropriate for recovering soil health, including nematode diversity, during reforestation of open tropical mines.

The evolution of habitat quality and its response to land use change in the coastal China, 1985-2020.

The coastal region of China is a typical area characterized by a developed economy, yet it faces prominent resource and environmental issues, and it is of great significance to quantitatively assess the ecological effects resulting from rapid urbanization and industrialization. Based on the land use data from 1985 to 2020, and the InVEST modeling and relevant spatial data sources, the paper analyzed the spatial and temporal changes in land use cover and habitat quality in the coastal China over the past 30 years. The results show that: 1) land use cover in the coastal China has changed significantly during the study period, with the area of cultivated land continuing to decrease and construction land expanding; 2) the trend of habitat quality degradation in was obvious, with the area of low-value habitat quality continuing to increase. Spatially, they were mainly located in the three major urban agglomerations undergoing rapid industrialization and urbanization; 3) The average degradation of habitats increased significantly between 1990 and 2000 and 2010-2020. The rate of change in areas with different degradation levels from 1990 to 2000 was higher than in other periods. The low-value areas of habitat degradation are mainly located in hilly and mountainous regions. 4) The transfer of habitat grades was generally characterized by a shift from high grade to low grade. This trend of conversion was due to the large-scale occupation of cultivated land by construction land and the long-term encroachment of ecological land by cultivated land. For future development, it is recommended to improve the land use regulation system based on the principles of sustainable development, with a particular focus on habitat protection. Additionally, efforts should be made to strengthen the development of ecological agriculture, carry out ecological protection and restoration, and improve the mechanisms for coordinating land and sea management.

Bayesian spatio-temporal modeling to assess the effect of land-use changes on the incidence of Cutaneous Leishmaniasis in the Brazilian Amazon.

Cutaneous Leishmaniasis (CL) is a vector-borne disease caused by a protozoan of the genus Leishmania and is considered one of the most important neglected tropical diseases. The Brazilian Amazon Forest harbors one of the highest diversity of Leishmania parasites and vectors and is one of the main focuses of the disease in the Americas. Previous studies showed that some types of anthropogenic disturbances have affected the abundance and distribution of CL vectors and hosts; however, few studies have thoroughly investigated the influence of different classes of land cover and land-use changes on the disease transmission risk. Here, we quantify the effect of land use and land-cover changes on the incidence of CL in all municipalities within the Brazilian Amazon Forest, from 2001 to 2017. We used a structured spatiotemporal Bayesian model to assess the effect of forest cover, agriculture, livestock, extractivism, and- deforestation on CL incidence, accounting for confounding variables such as population, climate, socioeconomic, and spatiotemporal random effects. We found that the increased risk of CL was associated with deforestation, especially modulated by a positive interaction between forest cover and livestock. Landscapes with ongoing deforestation for extensive cattle ranching are typically found in municipalities within the Amazon Frontier, where a high relative risk for CL was also identified. These findings provide valuable insights into developing effective public health policies and land-use planning to ensure healthier landscapes for people.

Anthropogenic and climatic impacts on historic sediment, carbon, and phosphorus accumulation rates using 210Pbex and 137Cs in a sub-watershed linked to Zarivar Lake, Iran.

To estimate a watershed's response to climate change, it is crucial to understand how human activities and climatic extremes have interacted over time. Over the last century, the Zarivar Lake watershed, Iran, has been subjected to various anthropogenic activates, including deforestation and inappropriate land-management practices alongside the implementation of conservation measures like check dams. To understand the effects of these changes on the magnitude of sediment, organic carbon (OC), and phosphorus supplies in a small sub-watershed connected to the lake over the last century, a lake sediment core was dated using 210Pbex and 137Cs as geochronometers. The average mass accumulation rate (MAR), organic carbon accumulation rates (OCAR), and particulate phosphorus accumulation rates (PPAR) of the sediment core were determined to be 6498 ± 2475, 205 ± 85, and 8.9 ± 3.3 g m-2 year-1, respectively. Between the late 1970s and early 1980s, accumulation rates were significantly higher than their averages at 7940 ± 3120, 220 ± 60, and 12.0 ± 2.8 g m-2 year-1 respectively. During this period, the watershed underwent extensive deforestation (12%) on steep slopes, coinciding with higher mean annual precipitations (more than double). Conversely, after 2009, when check dams were installed in the sub-watershed, the sediment load to the lake became negligible. The results of this research indicate that anthropogenic activities had a pronounced effect on MAR, OCAR, and PPAR, causing them to fluctuate from negligible amounts to values twice the averages over the last century, amplified by climatic factors. These results imply that implementing climate-smart watershed management strategies, such as constructing additional check dams and terraces, reinforcing restrictions on deforestation, and minimum tillage practices, can facilitate protection of lacustrine ecosystems under accelerating climate change conditions.

Mangrove wetland recovery enhances soil carbon sequestration capacity of soil aggregates and microbial network stability in southeastern China.

Mangrove wetlands are highly productive ecosystems in tropical and subtropical coastal zones, play crucial roles in water purification, biodiversity maintenance, and carbon sequestration. Recent years have seen the implementation of pond return initiatives, which have facilitated the gradual recovery of mangrove areas in China. However, the implications of these initiatives for soil aggregate stability, microbial community structure, and network interactions remain unclear. This study assesses the impacts of converting ponds to mangroves-both in natural and artificially restored settings-on soil aggregate stability and microbial networks at typical mangrove restoration sites along China's southeastern coast. Our observations confirmed our hypothesis that pond-to-mangrove conversions resulted in an increase in the proportion of large aggregates (>0.25 mm), improved soil aggregate structural stability, and increased carbon sequestration. However, mangrove recovery led to a decrease in the abundance and diversity of soil fungi communities. In terms of co-occurrence networks, naturally restored mangrove wetlands exhibited more nodes and edges. The naturally recovered mangrove wetlands demonstrated a higher level of community symbiosis compared to those that were manually restored. Conversely, bacterial networks showed a different pattern, with significant shifts in key taxa related to carbon sequestration functions. For instance, the proportion of bacterial Desulfobacterota and fungi Basidiomycota in natural recovery mangrove increased by 15.03 % and 7.82 %, respectively, compared with that in aquaculture ponds. Soil fungi and bacteria communities, as well as carbon sequestration by aggregates, were all positively correlated with soil total carbon content (P < 0.05). Both bacterial and fungal communities contributed to soil aggregate stability. Our study highlights the complex relationships between soil microbial communities, aggregate stability, and the carbon cycle before and after land-use changes. These findings underscore the potential benefits of restoring mangrove wetlands, as such efforts can enhance carbon storage capacity and significantly contribute to climate change mitigation.

Exploring soil nitrogen and sulfur dynamics: implications for greenhouse gas emissions on the Qinghai-Tibet Plateau.

The Qinghai-Tibet Plateau is particularly vulnerable to the effects of climate change and disturbances caused by human activity. To better understand the interactions between soil nitrogen and sulfur cycles and human activities on the plateau, the distribution characteristics of soil nitrogen and sulfur density and their influencing factors for three soil layers in Machin County at depths of 0-20 cm, 0-100 cm, and 0-180 cm are discussed in this paper. The results indicated that at depths of 0-180 cm, soil nitrogen density in Machin County varied between 1.36 and 16.85 kg/m2, while sulfur density ranged from 0.37 to 4.61 kg/m2. The effects of three factors-geological background, land use status, and soil type-on soil nitrogen and sulfur density were all highly significant (p < 0.01). Specifically, natural factors such as soil type and geological background, along with anthropogenic factors including land use practices and grazing intensity, were identified as decisive in causing spatial variations in soil nitrogen and sulfur density. Machin County on the Tibetan Plateau exhibits natural nitrogen and sulfur sinks; However, it is crucial to monitor the emissions of N2O and SO2 into the atmosphere from areas with high external nitrogen and sulfur inputs and low fertility retention capacities, such as bare land. On this basis, changes in the spatial and temporal scales of the nitrogen and sulfur cycles in soils and their source-sink relationships remain the focus of future research.

Multi-scenario prediction and attribution analysis of carbon storage of ecological system in the Huaihe River Basin, China.

Evaluating the impact of large-scale human activities on carbon storage through land use changes is of growing interest in terrestrial ecosystem assessments. The Huaihe River Basin, a vital Chinese grain production area, has undergone marked land use changes amid socio-economic acceleration. Evaluating the impacts of land use change on carbon storage and future carbon sequestration is imperative for regional ecosystem sustainability and Chinese food security, simultaneously, furnishing data support to regional land use planning and decision-making processes. Nonetheless, the mechanisms linking land use changes to carbon storage and the future carbon reservoir responses remain unclear. We utilized a multi-source dataset and representative scenarios, integrating PLUS, InVEST models, and Geodetector to assess land use change impacts on carbon storage in the Huaihe River Basin (2000-2030). The data indicates the following: (1) from 2000 to 2020, cultivated land decreased by 28,344.69 km2, construction land increased by 26,914.56 km2, and other land types changed little. (2) Land use change resulted a carbon loss of 1.17 × 108 t, primarily due to the expansion of construction land. (3) All four simulation scenarios exhibited diminished carbon storage relative to 2020, with the economic development scenario recording the lowest at 4.98 × 109 t and the ecological protection scenario the highest at 5.06 × 109 t. (4) Elevation predominantly drives carbon storage changes, with its interaction with NPP having the greatest impact. The factors synergistically enhance their explanatory power. The research provides a scientific basis for strategies aimed at augmenting regional carbon sequestration and refining low-carbon land management, safeguarding ecosystem stability.

Rethinking Urban Water Management Through Drivers-Pressures-States-Impacts-Responses Framework Application in Chennai, India.

Cities suffering water scarcity are projected to increase in the following decades. However, the application of standardized indicator frameworks for assessing urban water resource management problems is on an early stage. India is expected to have the highest urban population facing water scarcity in the world by 2050. In this study, the authors assess how the Drivers-Pressures-States-Impacts-Responses framework, a causal framework adopted by the European Environment Agency, can contribute to evaluate water management challenges in cities and apply it to Chennai, India´s fourth-largest urban agglomeration. The framework proved to be a helpful tool for the evaluation of water management challenges in cities by disentangling relationships between environmental indicators and structuring dispersed data that allows a better understanding for policymakers. The main drivers identified in Chennai were population growth and economic development which generated impacts such as loss of aquatic ecosystems, low water table, low water quality, and reduction of biodiversity and human health. As a response, better urban planning, projects for new water infrastructure, and water bodies restoration have been implemented. Nevertheless, Chennai keeps facing difficulties to achieve proper water management. The severe hit of the COVID-19 pandemic on the Indian economy and its future management will be key for achievements related to water management.

Differential contribution of microbial and plant-derived organic matter to soil organic carbon sequestration over two decades of natural revegetation and cropping.

Both natural revegetation and cropping have great impact on long-term soil carbon (C) sequestration, yet the differences in their underlying mechanisms remain unclear. In this study, we investigated trends in soil organic C (SOC) accumulation during natural revegetation (VR) and cropping processes over 24 years, and explored the contributions of microbial necromass and plant-derived C to SOC formation and their primary controls. Over the course of 24 years of land use/cover change (LUCC) from 1995, SOC content exhibited a more substantial increase in VR (0.31 g kg-1 a-1) than in cropland (0.14 g kg-1 a-1) during Stage II (>10 y after LUCC), and recalcitrant organic carbon explained more of the SOC variation than easily oxidizable carbon. The higher SOC content in VR was attributed to a greater contribution of plant-derived C (14-28 %) than that in cropland (3-11 %) to SOC and a consistently lower ratio of cinnamyl (C)- to vanillyl (V)-type phenols in VR across all the assessed years. Although there were higher proportion of microbial necromass of SOC (41-84 %) in cropland than in VR, the differences were not significant. The dominant bacterial phylum of Chloroflexi and soil nitrogen content were the primary biotic and abiotic factors regulating microbial-derived and plant-derived C in both cropland and VR. However, soil phosphorus content was the main factor in cropland, while climatic factors such as mean annual precipitation were more important in VR. These results provided evidence that long-term natural revegetation enhanced SOC sequestration by greater contribution of plant-derived C to SOC formation compared to cropping. These findings underscore the synergistic contribution of vegetation and microorganisms to long-term SOC sequestration, offering insights into the different mechanisms of carbon formation during VR and cropping processes, and providing support for optimizing land management to achieve global carbon neutrality goals.

A social-ecological approach to support equitable land use decision-making.

Human-driven land use change can result in unequitable outcomes in the provision and appropriation of ecosystem services (ES). To better address equity-related effects of land use change in decision-making, analyses of land use and ES changes under different land use management alternatives should incorporate ecological and social information and take a disaggregated approach to ES analysis. Because such approaches are still scarce in the literature, we present a generalized social-ecological approach to support equitable land use decision-making (in terms of process and outcomes) and an example of its application to a case study in southwestern Ethiopia. We propose a six-step approach that combines scenario planning with equity-focused, disaggregated analyses of ES. Its application in our study area made equity-related effects of land use change explicit through the recognition of different beneficiary groups, value types, and spatial locations. We recommend the application of our approach in other contexts, especially in the Global South.

From chocolate to palm oil: The future of Indonesia's cocoa plantations.

Indonesia is the world's third largest cocoa producer, but production is decreasing since 2011. We revisited cocoa farmers for an environmental assessment in Luwu Timur, Sulawesi, 7 months after a socio-economic survey on cocoa certification outcomes and observed many cocoa plantations being converted into oil palm and maize. Including our field data as well as secondary data on commodity prices and yields, we outline reasons for cocoa conversion, potential consequences for biodiversity, and assess the future outlook for the Indonesian cocoa sector. Low cocoa productivity, volatile cocoa prices and higher revenue for oil palm, among others, drive land-use change. If shade trees are cut during cocoa conversion, it may have negative implications for biodiversity. Solutions to low soil fertility, omnipresent pests and diseases, and stable producer prices are needed to increase profitability of cocoa and prevent conversion of cocoa agroforests to oil palm monocultures.