Transient social-ecological dynamics reveal signals of decoupling in a highly disturbed Anthropocene landscape.

Understanding the transient dynamics of interlinked social-ecological systems (SES) is imperative for assessing sustainability in the Anthropocene. However, how to identify critical transitions in real-world SES remains a formidable challenge. In this study, we present an evolutionary framework to characterize these dynamics over an extended historical timeline. Our approach leverages multidecadal rates of change in socioeconomic data, paleoenvironmental, and cutting-edge sedimentary ancient DNA records from China's Yangtze River Delta, one of the most densely populated and intensively modified landscapes on Earth. Our analysis reveals two significant social-ecological transitions characterized by contrasting interactions and feedback spanning several centuries. Initially, the regional SES exhibited a loosely connected and ecologically sustainable regime. Nevertheless, starting in the 1950s, an increasingly interconnected regime emerged, ultimately resulting in the crossing of tipping points and an unprecedented acceleration in soil erosion, water eutrophication, and ecosystem degradation. Remarkably, the second transition occurring around the 2000s, featured a notable decoupling of socioeconomic development from ecoenvironmental degradation. This decoupling phenomenon signifies a more desirable reconfiguration of the regional SES, furnishing essential insights not only for the Yangtze River Basin but also for regions worldwide grappling with similar sustainability challenges. Our extensive multidecadal empirical investigation underscores the value of coevolutionary approaches in understanding and addressing social-ecological system dynamics.

Evaluating the relative influence of climate and human activities on recent vegetation dynamics in West Bengal, India.

Assessing the relative importance of climate change and human activities is important in developing sustainable management policies for regional land use. In this study, multiple remote sensing datasets, i.e. CHIRPS (Climate Hazard Group InfraRed Precipitation with Station Data) precipitation, MODIS Land Surface Temperature (LST), Enhanced Vegetation Index (EVI), Potential Evapotranspiration (PET), Soil Moisture (SM), WorldPop, and nighttime light have been analyzed to investigate the effect that climate change (CC) and regional human activities (HA) have on vegetation dynamics in eastern India for the period 2000 to 2022. The relative influence of climate and anthropogenic factors is evaluated on the basis of non-parametric statistics i.e., Mann-Kendall and Sen's slope estimator. Significant spatial and elevation-dependent variations in precipitation and LST are evident. Areas at higher elevations exhibit increased mean annual temperatures (0.22 °C/year, p < 0.05) and reduced winter precipitation over the last two decades, while the northern and southwest parts of West Bengal witnessed increased mean annual precipitation (17.3 mm/year, p < 0.05) and a slight cooling trend. Temperature and precipitation trends are shown to collectively impact EVI distribution. While there is a negative spatial correlation between LST and EVI, the relationship between precipitation and EVI is positive and stronger (R2 = 0.83, p < 0.05). Associated hydroclimatic parameters are potent drivers of EVI, whereby PET in the southwestern regions leads to markedly lower SM. The relative importance of CC and HA on EVI also varies spatially. Near the major conurbation of Kolkata, and confirmed by nighttime light and population density data, changes in vegetation cover are very clearly dominated by HA (87%). In contrast, CC emerges as the dominant driver of EVI (70-85%) in the higher elevation northern regions of the state but also in the southeast. Our findings inform policy regarding the future sustainability of vulnerable socio-hydroclimatic systems across the entire state.

Quantifying climate variability and regional anthropogenic influence on vegetation dynamics in northwest India.

To explore the spatio-temporal dynamics and mechanisms underlying vegetation cover in Haryana State, India, and implications thereof, we obtained MODIS EVI imagery together with CHIRPS rainfall and MODIS LST at annual, seasonal and monthly scales for the period spanning 2000 to 2022. Additionally, MODIS Potential Evapotranspiration (PET), Ground Water Storage (GWS), Soil Moisture (SM) and nighttime light datasets were compiled to explore their spatial relationships with vegetation and other selected environmental parameters. Non-parametric statistics were applied to estimate the magnitude of trends, along with correlation and residual trend analysis to quantify the relative influence of Climate Change (CC) and Human Activities (HA) on vegetation dynamics using Google Earth Engine algorithms. The study reveals regional contrasts in trends that are evidently related to elevation. An annual increasing trend in rainfall (21.3 mm/decade, p < 0.05), together with augmented vegetation cover and slightly cooler (-0.07 °C/decade) LST is revealed in the high-elevation areas. Meanwhile, LST in the plain regions exhibit a warming trend (0.02 °C/decade) and decreased in vegetation and rainfall, accompanied by substantial reductions in GWS and SM related to increased PET. Linear regression demonstrates a strongly significant relationship between rainfall and EVI (R2 = 0.92), although a negative relationship is apparent between LST and vegetation (R2 = -0.83). Additionally, increased LST in the low-elevation parts of the study area impacted PET (R2 = 0.87), which triggered EVI loss (R2 = 0.93). Moreover, increased HA resulted in losses of 25.5 mm GSW and 1.5 mm SM annually. The relative contributions of CC and HA are shown to vary with elevation. At higher elevations, CC and HA contribute respectively 85% and 15% to the increase in EVI. However, at lower elevations, reduced EVI is largely (79%) due to human activities. This needs to be considered in managing the future of vulnerable socio-ecological systems in the state of Haryana.

Ecological restoration for sustainable development in China.

Facing the need for transdisciplinary research to promote ecological restoration that achieves both social and ecological benefits, research on past restoration efforts that have directly or indirectly contributed to regional or national sustainable development warrants reassessment. Using China as an example, in this review, we address three basic research questions that can be summarized as follows: ecological restoration-of what, for whom and to what purpose? Accordingly, a 'landscape pattern-ecosystem service-sustainable development' co-evolutionary framework is proposed here to describe landscape-scale ecological restoration and its impact on landscape patterns and ecological processes, ecosystem services for human well-being, sustainable livelihoods and socioeconomic development. From the strategic pattern of national ecological security to the pattern of major projects to protect and restore major national ecosystems, the spatial pattern of China's ecological restoration is more geographically integrative. From major function-oriented zoning to systematic ecological protection and restoration, and for the purpose of achieving the Beautiful China Initiative, there are three stages of ecosystem services management: classification, synergy and integration, respectively. The difference in geographic processes should be considered in the key requirements of ecological restoration for China's five national strategies for regional sustainable-development strategies. Deepening understanding of the relationship between humans and nature in different geographical contexts is a scientific prerequisite to support policymaking related to ecological restoration. To promote greater harmony between humans and nature, we propose four important research directions: (i) understanding coupling processes among key components, (ii) identifying ecosystem service flows, (iii) evaluating social-ecological benefits and (iv) supporting adaptive management for regional sustainable development.

Widespread global disparities between modelled and observed mid-depth ocean currents.

The mid-depth ocean circulation is critically linked to actual changes in the long-term global climate system. However, in the past few decades, predictions based on ocean circulation models highlight the lack of data, knowledge, and long-term implications in climate change assessment. Here, using 842,421 observations produced by Argo floats from 2001-2020, and Lagrangian simulations, we show that only 3.8% of the mid-depth oceans, including part of the equatorial Pacific Ocean and the Antarctic Circumpolar Current, can be regarded as accurately modelled, while other regions exhibit significant underestimations in mean current velocity. Knowledge of ocean circulation is generally more complete in the low-latitude oceans but is especially poor in high latitude regions. Accordingly, we propose improvements in forecasting, model representation of stochasticity, and enhancement of observations of ocean currents. The study demonstrates that knowledge and model representations of global circulation are substantially compromised by inaccuracies of significant magnitude and direction, with important implications for modelled predictions of currents, temperature, carbon dioxide sequestration, and sea-level rise trends.

Pixel level spatial variability modeling using SHAP reveals the relative importance of factors influencing LST.

As an important indicator of the regional thermal environment, land surface temperature (LST) is closely related to community health and regional sustainability in general, and is influenced by multiple factors. Previous studies have paid scant attention to spatial heterogeneity in the relative contribution of factors underlying LST. In this study of Zhejiang Province, we investigated the key factors affecting daytime and nighttime annual mean LST and the spatial distribution of their respective contributions. The eXtreme Gradient Boosting tree (XGBoost) and Shapley Additive exPlanations algorithm (SHAP) approach were used in combination with three sampling strategies (Province-Urban Agglomeration -Gradients within Urban Agglomeration) to detect spatial variation. The results reveal heterogenous LST spatial distribution with lower LST in the southwestern mountainous region and higher temperatures in the urban center. Spatially explicit SHAP maps indicate that latitude and longitude (geographical locations) are the most important factors at the provincial level. In urban agglomerations, factors associated with elevation and nightlight are shown to positively impact daytime LST in lower altitude regions. In the urban centers, EVI and MNDWI are the most notable influencing factors on LST at night. Under different sampling strategies, EVI, MNDWI, NL, and NDBI affect LST more prominently at smaller spatial scales as compared to AOD, latitude and TOP. The SHAP method proposed in this paper offers a useful means for management authorities in addressing LST in a warming climate.

The timing and magnitude of anthropogenic mercury pollution: A 200-year record from multi-lake sediment cores in northeast China.

The recent substantial expansion of human activities in northeast (NE) China has resulted in increased emission of environmental pollutants. Longer-term records of such environmental pollutants provide a benchmark against which it is possible to evaluate the nature, extent and timing of anthropogenic environmental changes. Based on measurements of mercury (Hg) concentrations and accumulation rates in 11 lake sediment cores from the Songnen Plain in NE China, we here present a reconstruction of the historical deposition of Hg as an indicator of the changing scale of human impact. The results demonstrate an increasing trend of Hg concentration, concurrent with elevated anthropogenic emissions, beginning from the early 1900s, accelerating through the mid-1950s and slightly decreasing from the late 1990s onwards. The increase in anthropogenic Hg coincides with the reform and opening up of China, which precipitated social and economic transformation, and rapid industrial and economic growth. Measurements of the Hg enrichment factor in all the cores enables identification of the anthropogenic contribution to Hg accumulation. The geoaccumulation index indicates that the lakes are in general moderately polluted by Hg. The historical trend of Hg accumulation rate parallels the temporal progression of biomass burning and fossil fuel consumption in the region. The findings elucidate the extent of anthropogenic pollution in the Anthropocene and underline the importance of identifying Hg sources to reduce emissions and guide the implementation of effective mitigation strategies.

Achieving the Sustainable Development Goals in the post-pandemic era.

The COVID-19 pandemic continues to pose substantial challenges to achieving the Sustainable Development Goals (SDGs). Exploring systematic SDG strategies is urgently needed to aid recovery from the pandemic and reinvigorate global SDG actions. Based on available data and comprehensive analysis of the literature, this paper highlights ongoing challenges facing the SDGs, identifies the effects of COVID-19 on SDG progress, and proposes a systematic framework for promoting the achievement of SDGs in the post-pandemic era. Progress towards attaining the SDGs was already lagging behind even before the onset of the COVID-19 pandemic. Inequitable distribution of food-energy-water resources and environmental crises clearly threaten SDG implementation. Evidently, there are gaps between the vision for SDG realization and actual capacity that constrain national efforts. The turbulent geopolitical environment, spatial inequities, and trade-offs limit the effectiveness of SDG implementation. The global public health crisis and socio-economic downturn under COVID-19 have further impeded progress toward attaining the SDGs. Not only has the pandemic delayed SDG advancement in general, but it has also amplified spatial imbalances in achieving progress, undermined connectivity, and accentuated anti-globalization sentiment under lockdowns and geopolitical conflicts. Nevertheless, positive developments in technology and improvement in environmental conditions have also occurred. In reflecting on the overall situation globally, it is recommended that post-pandemic SDG actions adopt a "Classification-Coordination-Collaboration" framework. Classification facilitates both identification of the current development status and the urgency of SDG achievement aligned with national conditions. Coordination promotes domestic/international and inter-departmental synergy for short-term recovery as well as long-term development. Cooperation is key to strengthening economic exchanges, promoting technological innovation, and building a global culture of sustainable development that is essential if the endeavor of achieving the SDGs is to be successful. Systematic actions are urgently needed to get the SDG process back on track.

Catalytic non-thermal plasma treatment of endocrine disrupting compounds, pharmaceuticals, and personal care products in aqueous solution: A review.

Contaminants of emerging concerns such as endocrine-disrupting compounds (EDCs) and pharmaceuticals/personal-care products (PPCPs) constitute a problem since they are not completely eliminated by traditional water and wastewater treatment methods. Non-thermal plasma (NTP) is considered as one of the most favorable treatment methods for the removal of organic contaminants in water and wastewater. The degradation of selected EDCs and PPCPs of various classes was reviewed, based on the recent literature, to (i) address the effect of the main NTP treatment parameters (water quality and NTP conditions: pH, initial concentration, temperature, background common ion, NOM, scavenger, gas type/flow rate, discharge/reactor type, input power, and energy efficiency/yield) on the degradation of contaminants and their intermediates, (ii) assess the influences of different catalysts and hybrid systems on degradation, (iii) describe EDC and PPCP degradation along with their properties, and (iv) evaluate mineralization, pathway, and degradation mechanism of selected EDCs and PPCPs for different cases studied. Furthermore, areas of potential research in NTP treatment for the degradation of EDCs and PPCPs in aqueous solutions are recommended. It could be reasonably predicted that this review is valid for developing our understanding of the fundamental scientific principles concerning the catalytic NTP of EDCs and PPCPs, providing helpful and practical references for researchers and designers on the effective removal of EDCs/PPCPs and the optimized operation of catalytic NTP systems.

Rapid greening response of China's 2020 spring vegetation to COVID-19 restrictions: Implications for climate change.

The 2019 novel coronavirus pandemic (COVID-19) negatively affected global public health and socioeconomic development. Lockdowns and travel restrictions to contain COVID-19 resulted in reduced human activity and decreased anthropogenic emissions. However, the secondary effects of these restrictions on the biophysical environment are uncertain. Using remotely sensed big data, we investigated how lockdowns and traffic restrictions affected China's spring vegetation in 2020. Our analyses show that travel decreased by 58% in the first 18 days following implementation of the restrictions across China. Subsequently, atmospheric optical clarity increased and radiation levels on the vegetation canopy were augmented. Furthermore, the spring of 2020 arrived 8.4 days earlier and vegetation 17.45% greener compared to 2015-2019. Reduced human activity resulting from COVID-19 restrictions contributed to a brighter, earlier, and greener 2020 spring season in China. This study shows that short-term changes in human activity can have a relatively rapid ecological impact at the regional scale.

Differential effects of various reclamation treatments on soil characteristics: an experimental study of newly reclaimed tidal mudflats on the east China coast.

Reclamation of coastal land is increasingly being used as a means of raising agricultural productivity and improving food security in China. Applications of organic and inorganic supplements on reclaimed soils can significantly adjust a range of soil properties, C, N, P content and stoichiometry, and extracellular enzyme activities. However, the linkages between soil C꞉N꞉P stoichiometry and extracellular enzyme activities following reclamation of coastal saline soil remain largely unclear. In this experimental study, treatments included control (CK), chicken manure (OM), polyacrylamide plus chicken manure (PAM+OM), straw mulching plus chicken manure (SM + OM), buried straw plus chicken manure (BS + OM), and bio-organic manure plus chicken manure (BM + OM) were conducted to explore the linkages between soil physicochemical characteristics in reclaimed soils under different treatments and to evaluate their impact on oat yield. Soils under all reclamation treatments exhibited higher moisture content and, with the exception of SM + OM, lower soil pH compared to the control. The reclamation treatments also significantly decreased soil bulk density (BD) and soil salt content (SSC), and increased soil organic carbon (SOC), total nitrogen (TN) and organic phosphorus (OP). Our study of soil C꞉N꞉P stoichiometry revealed that newly reclaimed soils in the study area are N limited. Additionally, soil invertase (INV), urease (URE) and alkaline phosphatase (ALP) activity under different reclamation treatments were significantly enhanced compared with CK in surface soil, while soil catalase (CAT) activity was observed to be much higher in BM + OM than in other treatments. Mean oat yields for each of the treatments were ranked as follows: BM + OM > SM + OM > PAM + OM > BS + OM > OM > CK treatment. Our results also indicate that TN (12.1% and 12.4%) was the main factor affecting URE and ALP, whereas BD (13.5%) and pH (8.5) were key factors affecting INV and CAT activity, respectively.

Human impact on C/N/P accumulation in lake sediments from northeast China during the last 150 years.

Lakes and lake sediments are significant components of the global carbon (C) cycle, and may store very large amounts of organic matter. Carbon sequestration in lakes is subject to substantial temporal and spatial variation and may be strongly affected by human activities. Here, we report accumulation rates (AR) of organic C (OC), total nitrogen (TN) and total phosphorous (TP), and investigate their responses to anthropogenic impact over the past 150 years by analyzing 62 sediment cores from 11 shallow lakes in the Songnen Plain, northeast China. From the center of each of the lakes, we selected one master core for age determination by 210Pb and 137Cs radioisotopes. The contents of OC, TN, TP, dry bulk density and mass specific magnetic susceptibility were then determined for all cores. The regional OCAR, TNAR and TPAR up-scaling from the multiple cores yielded mean values of 51.63 ± 15.13, 2.50 ± 0.98, and 0.90 ± 0.21 g m-2 yr-1, respectively. Nutrient AR in the studied lakes increased by a factor of approximately 2 × from the middle 19th century to the 1950s, and approximately 5 × after the 1950s. Elemental ratios show that the increase in OCAR is mainly the result of C autogenesis from the growth of aquatic plants stimulated by agricultural intensification, including increased chemical fertilizer application and farmland expansion. Significantly enhanced nutrient burial by these lakes after the 1950s resulted from increased anthropogenic impacts in northeast China. More sustainable agricultural practises, including a decrease in P fertilizer use, would result in a lowering of OCAR, TNAR and TPAR in the future.

Occurrence and distribution of PAHs and microbial communities in nearshore sediments of the Knysna Estuary, South Africa.

This study investigated the polycyclic aromatic hydrocarbons (PAHs) occurrence, and their impact on the microbial community and PAH-degrading genera and genes in the Knysna Estuary of South Africa. The results reveal that the estuary exhibits low PAH levels (114.1-356.0 ng g-1). Ignavibacteriae and Deferribacteres, as well as Proteobacteria and Bacteroidetes, are keystone phyla. Among measured environmental factors, total organic carbon (TOC), nutrients such as nitrite and nitrate, metals as Al, Cr, Cu, Ni, Pb and Zn, and environmental properties (pH and salinity) are primary contributors to structuring the bacterial community assemblage. The abundance of alpha subunit genes of the PAH-ring hydroxylating dioxygenases (PAH-RHDα) of Gram-negative bacteria lies in the range of (2.0-4.2) × 105 copies g-1, while that of Gram-positive bacteria ranges from 3.0 × 105 to 1.3 × 107 copies g-1. The PAH-degrading bacteria account for up to 0.1% of the bacterial community and respond mainly to nitrate, TOC and salinity, while PAHs at low concentration are not significant influencing factors. PAH degraders such as Xanthomonadales, Pseudomonas, and Mycobacterium, which play a central role in PAH-metabolization coupled with other biogeochemical processes (e.g. iron cycling), may contribute to maintaining a healthy estuarine ecosystem. These results are important for developing appropriate utilization and protection strategies for pristine estuaries worldwide.

Gaining or losing ground? Tracking Asia's hunger for 'new' coastal land in the era of sea level rise.

Many coastal cities are short of land for development and, coupled with the need to mitigate the impact of extreme events against a background of ongoing sea-level rise, coastal land reclamation (CLR) has emerged as a frequently applied solution, most especially in Asia. However, the sustainability of these newly reclaimed lands under the combined onslaught of increasing population pressure, SRL, greater frequency of extreme events, and land subsidence is largely unknown. In order to assess the spatial extent and temporal trends in recent CLR projects, we mapped and tabulated the annual magnitude of change in coastal land gain from 1988 to 2018 for eight major Asian coastal cities. Across these cities, both the spatial extent and rate of CLR is remarkable; some 700 km2 has been reclaimed in just three decades. >35% of this new coastal land has been constructed in Shanghai alone (562 km2), while Singapore and Incheon have also experienced substantial land gains. These three cities alone account for almost 10% of all the land gained globally over the last three decades. An analysis of the spatio-temporal patterns reveals that, since recently reclaimed areas are predominantly characterized by construction, including ports, airports, commercial and residential uses, economic development is the most prominent driver. Shanghai, however, represents a significant departure from this trend, whereby >50% of the new coastal land gained during the recent past has not been devoted to construction projects and is vegetated, suggesting a different policy context. Commercial or otherwise, subsidence is widely reported as a major characteristic of recently reclaimed coastal land and is a major environmental challenge. Mapping recent rates of land subsidence over these newly reclaimed lands reveal that most are subject to significant levels of deformation, in the case of the international airport at Incheon, Republic of Korea, exceeding 25 cm annually.

Land Cover Change Intensifies Actual and Potential Radiative Forcing through CO2 in South and Southeast Asia from 1992 to 2015.

Land cover change (LCC) and its impact on CO2 sequestration and radiative forcing (RF) could dramatically affect climate change, but there has been little effort to address this issue in South and Southeast Asia over a long period of time using actual land cover information. In this study, annual land cover data from 1992 to 2015 were used to assess the CO2 flux and corresponding RF due to LCC in South and Southeast Asia. The results showed that 553.2 × 103 km2 of the region experienced LCC during this period, mostly due to land reclamation, urban expansion, and deforestation. These LCC caused a marked net decrease in net ecosystem productivity (NEP) as a composite of the various land cover categories during the whole study period, especially since 2001. The CO2 sequestration was 2160 TgCO2 during the early 1990s however cumulative sequestration decreased by 414.95 TgCO2 by 2015. Correspondingly, the cooling effect of NEP, i.e. the total actual RF, was -0.366 W m-2 in South and Southeast Asia between 1992 and 2015. However, the potential RF of the cumulatively reduced NEP due to LCC relative to the 1990s resulted in a warming effect of 2.33 × 10-3 W m-2 in 2015. Our study provides an applicable framework to accurately assess the potential effect of large-scale LCC on climate.

Gastrointestinal cancer and brain metastasis: a rare and ominous sign.

Metastatic brain tumors represent 20% to 40% of all intracranial neoplasms and are found most frequently in association with lung cancer (50%) and breast cancer (12%). Although brain metastases occur in <4% of all tumors of the gastrointestinal (GI) tract, the incidence of GI brain metastasis is rising in part due to more effective systemic treatments and prolonged survival of patients with GI cancer. Data were collected from 25 studies (11 colorectal, 7 esophageal, 2 gastric, 1 pancreatic, 1 intestinal, 3 all-inclusive GI tract cancer) and 13 case reports (4 pancreatic, 4 gallbladder, and 5 small bowel cancer). Brain metastases are found in 1% of colorectal cancer, 1.2% of esophageal cancer, 0.62% of gastric cancer, and 0.33% of pancreatic cancer cases. Surgical resection with whole brain radiation therapy (WBRT) has been associated with the longest median survival (38.4-262 weeks) compared with surgery alone (16.4-70.8 weeks), stereotactic radiosurgery (20-38 weeks), WBRT alone (7.2-16 weeks), or steroids (4-7 weeks). Survival in patients with brain metastasis from GI cancer was found to be diminished compared with metastases arising from the breast, lung, or kidney. Prolonged survival and improvement in clinical symptoms has been found to be best achieved with surgical resection and WBRT. Although early treatment has been linked to prolonged survival and improved quality of life, brain metastases represent a late manifestation of GI cancers and remain an ominous sign.

Intraabdominal Intravascular Papillary Endothelial Hyperplasia (Masson's Tumor): A Rare and Novel Cause of Gastrointestinal Bleeding.

Intravascular papillary endothelial hyperplasia (IPEH), or Masson's tumor, a rare benign vascular lesion, occurs mainly in the head, neck, and hands in the human population. Aberrant tumor locations have been rarely reported. We present a case of a patient with chronic abdominal pain and melena of variable severity due to a Masson's tumor, with no apparent Masson's tumor-associated comorbidities, along with a comprehensive review of the literature. Using PubMed, a search engine provided by the U.S. National Library of Medicine and the National Institutes of Health, we searched for all reports of Masson's tumor limited within the abdominal cavity. Furthermore, keywords such as 'intravascular papillary endothelial hyperplasia', 'renal', 'gastrointestinal', 'hepatic' and 'intraabdominal' were used to facilitate the search. We thus found fourteen cases of intraabdominal Masson's tumors published. Six (42.9%) of these were located in the renal vein, 4 (28.6%) were reported in the gastrointestinal tract, 1 (7.1%) in the adrenal gland, 1 (7.1%) in the liver, and 1 (7.1%) instance with multiple lesion sites including the renal hilum and retroperitoneum. Among these patients, 9 (64.3%) were female and 5 (35.7%) male, with a mean age of 38.9 years (7-69). IPEH is a reactive process, having three subtypes, all involving the proliferation of epithelial cells around a thrombus in the setting of venous stasis. In its pure form, the organized thrombus is solely localized within the vascular lumen. Mixed-form IPEH is formed in preexisting vascular lesions (such as arteriovenous malformation, hemangioma, pyogenic granuloma, etc.). The rarest form is the extravascular variety, which arises in hematomas often from recent trauma to the area. In its pure form, IPEH has a zero recurrence rate when an R0 resection is performed; all mixed and extravascular forms show the highest recurrence rates. The exact histogenesis of these epithelial cells remains a mystery and multiple theories have been offered. Although difficult to distinguish from malignant angiosarcomas solely on presentation and radiologic work-up, Masson's tumors occur more frequently in women, demonstrate no local invasion, do not metastasize, are commonly located intravascularly, and are associated with a significantly more favorable prognosis than angiosarcomas. Only four Masson's tumors have been reported in the gastrointestinal tract, two of these cases were related to microvascular thrombosis secondary to paroxysmal nocturnal hemoglobinuria and two were formed secondary to arteriovenous malformations. Our case lacked solitary evidence of either of these comorbidities. An incidental finding of an enlarged ovary, which was removed during our exploratory laparoscopy, plus strong demographic statistics that suggest women have an increased prevalence of this lesion may help support a hormonal theory of pathogenesis.