Power, politics and policy in the appropriation of urban wetlands: the critical case of Sri Lanka

Little is known about the drivers and governance strategies of appropriation of urban nature in the global south. We compare urban land-grabbing in the city of Colombo, Sri Lanka, with broader understanding of rural land-grabbing in the developing world. We show that the colonial legacy of appropriation and alteration of urban wetlands in Colombo has attained new heights in the neo-liberal period. This cyclical process has caused acute irreversible damage to the wetland ecosystem and a vast majority of the urban poor, with the marginalised continuing to suffer dispossession and environmental hazard. In recognition of the inherent limitations of 'uncontrollable' hybrid ecologies, potent social struggles have emerged to resist the continued appropriation agenda. As this cycle is perpetuated, broader social struggles for democratic urban governance have overtaken the pursuit of narrow political-economic goals and internal policy reform

The eco-social transformation of urban wetlands: A case study of Colombo, Sri Lanka

Recent studies in both the environmental sciences and geography highlight unforeseen ecological transformations occurring in eco-social landscapes. These transformations often result in 'novel' or 'hybrid' ecosystems that differ from the original ecosystems both in ecological character and social setting. However, little is known about the causes, consequences, and dynamics of such transformations in complex urban environments and the consequences for highly sensitive ecosystem types such as wetlands. This paper investigates the environmental history and recent ecological transformations in the urban wetlands of Colombo, Sri Lanka. Our methodology includes a combination of techniques from environmental history, wetland science and urban ecology. We investigate the ecological changes in the wetlands from colonial times to the present and establish relationships among wetland ecology (the hydro-soil-vegetation nexus), landscape change, community, and governance factors. We conclude that from 1980 onwards, the Colombo urban wetlands have undergone an overall transformation in both wetland type (composition and structure) and the social setting. Hydrological modification, watershed urbanization and the changes in ecosystem use were identified as the main causes of wetland transformation with the causes and consequences of the transformation having complex feedback loops. We synthesize these relationships into a post hoc conceptual model that will be of broader utility as a general framework to understand eco-social interactions in the governance of urban ecosystems

Cooperative expression of monocyte chemoattractant protein 1 within the bovine corpus luteum: Evidence of immune cell-endothelial cell interactions in a coculture system

Endothelial cells (EC) of the bovine corpus luteum (CL) are a known source of proinflammatory mediators, including monocyte chemoattractant protein 1 (CCL2) and endothelin 1 (EDN1). Here, a coculture system was devised to determine if immune cells and PGF(2 alpha) together affect CCL2 and EDN1 secretion by EC. Luteal EC were cultured either alone or together with peripheral blood mononuclear cells (PBMC), and treated without or with PGF(2 alpha) for 48 h (n = 6 experiments). Coculture of EC with PBMC increased CCL2 secretion an average of 5-fold higher compared with either cell type alone (P 0.05). EC cocultured with concanavalin A-activated PBMC (ActPBMC) increased CCL2 secretion an average of 12-fold higher compared with controls (P 0.05). Interestingly, PGF(2 alpha) did not alter either CCL2 or EDN1 secretion, regardless of culture conditions (P \u3e 0.05). In a second series of experiments (n = 3 experiments), mixed luteal cells (MLC) were cultured alone or with PBMC as described above. Secretion of CCL2 and EDN1 was not affected by co-culture or by PGF(2 alpha) (P \u3e 0.05), but MLC produced less progesterone in the presence of ActPBMC (P \u3c 0.05). Collectively, these results suggest that immune cells and EC can interact cooperatively to increase CCL2 secretion in the CL, but this interaction does not affect EDN1 secretion nor is it influenced by PGF(2 alpha). Additionally, activated immune cells appear to produce a factor that impairs progesterone production by luteal steroidogenic cells

Anti-Fibrotic and Anti-Angiogenic Activities of Osbeckia octandra Leaf Extracts in Thioacetamide-Induced Experimental Liver Cirrhosis

Chronic liver inflammation has become a major global health concern. In the absence of clinical surrogate markers to diagnose inflammatory liver disease, the intervention with effective drugs in modern medicine tends to be late. In Sri Lanka, traditional medical practitioners prescribe herbal preparations from Osbeckia octandra for the prevention and treatment of liver disorders. To test the efficacy of such treatments, we have administered thioacetamide (TAA) to male Wistar rats to induce chronic liver damage (disease control; DC) and examined how various leaf extracts: crude leaf suspension (CLS), boiled leaf extract (BLE), sonicated leaf extract (SLE), methanol leaf extract (MLE) and hexane leaf extract (HLE) of O. octandra ameliorate TAA-induced liver disease. The CLS, BLE and SLE treatments in cirrhotic rats significantly attenuated disease-related changes, such as liver weight and hepato-enzymes. The mRNA levels of Tnf-α were significantly decreased by 3.6, 10 and 3.9 times in CLS, BLE and SLE compared to DC. The same treatments resulted in significantly lower (19.5, 4.2 and 2.4 times) α-Sma levels compared to DC. In addition, Tgf-β1 and Vegf-R2 mRNA expressions were significantly lower with the treatments. Moreover, BLE expressed a strong anti-angiogenic effect. We conclude that CLS, BLE and SLE from O. octandra have potent hepatic anti-fibrotic effects in TAA-induced liver cirrhosis

Governing the urban wetlands: a multiple case-study of policy, institutions and reference points

Worldwide, coastal and floodplain wetlands are rapidly urbanizing, making them highly vulnerable to biodiversity loss, biological invasion and climate change. Yet urban wetlands management is an understudied area of global environmental research. Different policy approaches and institutional arrangements in place for urban wetlands governance have to be studied comparatively to obtain a better understanding of the current issues. This paper investigates four urban wetland policy regimes and the application of ecological reference points across four countries. The regimes are discussed within the context of global policy trends, urbanization patterns and environmental change. The analysis illustrates that the four cases deviate substantially in certain characteristics and converge in others. Global trends such as environmental treaties and restructuring of city spaces are common policy drivers for all cases. Conversely, the localized specific problems have yielded specialized policy responses in each case. Declaration of fixed biological reference points for wetlands were not used at any stage of the policy development process. However, the wetland managers formally or informally set up ecosystem-services oriented benchmarks for urban wetland management. Globally-applicable normative policy directives or universal ecological reference points seem bound to fail in urban wetlands governance. However, in designing effective urban wetland policy and institutions at the regional scale, both context-specific and generalized lessons from empirical policy evaluation of multiple case studies need to be jointly considered. Based on the characteristics of the policy regimes analysed in this study, a hypothetical framework for urban wetland policy evaluation is proposed; this has yet to be validated by empirical application to actual cases