The increasing success of invasive plant species in wetland areas can threaten their capacity to store carbon, nitrogen, and phosphorus (C, N, and P). Here, we have investigated the relationships between the different stocks of soil organic carbon (SOC), and total C, N, and P pools in the plant–soil system from eight different wetland areas across the South‐East coast of China, where the invasive tallgrass Spartina alterniflora has replaced the native tall grasses Phragmites australis and the mangrove communities, originally dominated by the native species Kandelia obovata and Avicennia marina. The invasive success of Spartina alterniflora replacing Phragmites australis did not greatly influence soil traits, biomass accumulation or plant–soil C and N storing capacity. However, the resulting higher ability to store P in both soil and standing plant biomass (approximately more than 70 and 15 kg P by ha, respectively) in the invasive than in the native tall grass communities suggesting the possibility of a decrease in the ecosystem N:P ratio with future consequences to below‐ and aboveground trophic chains. The results also showed that a future advance in the native mangrove replacement by Spartina alterniflora could constitute a serious environmental problem. This includes enrichment of sand in the soil, with the consequent loss of nutrient retention capacity, as well as a sharp decrease in the stocks of C (2.6 and 2.2 t C ha‐1 in soil and stand biomass, respectively), N, and P in the plant–soil system. This should be associated with a worsening of the water quality by aggravating potential eutrophication processes. Moreover, the loss of carbon and nutrient decreases the potential overall fertility of the system, strongly hampering the reestablishment of woody mangrove communities in the future.

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This paper reports how endogenous economic growth and technological change have been introduced into a global econometric model. It explains how further technological change might be induced by mitigation policies so as to reduce greenhouse gas emissions and stabilize atmospheric concentrations. These are the first results of a structural econometric approach to modeling the global economy using the model E3MG (energy-environment-economy model of the globe), which in turn constitutes one component in the Community Integrated Assessment System (CIAS) of the UK Tyndall Centre. The model is simplified to provide a post-Keynesian view of the long-run, with an indicator of technological progress affecting each region's exports and energy use. When technological progress is endogenous in this way, long-run growth in global GDP is partly explained by the model. Average permit prices and tax rates about $430/tC (1995) prices after 2050 are sufficient to stabilize atmospheric concentrations at 450ppm CO 2 after 2100. They also lead to higher economic growth.

This paper describes the development and first results of the "Community Integrated Assessment System" (CIAS), a unique multi-institutional modular and flexible integrated assessment system for modelling climate change. Key to this development is the supporting software infrastructure, SoftIAM. Through it, CIAS is distributed between the communities of institutions which has each contributed modules to the CIAS system. At the heart of SoftIAM is the Bespoke Framework Generator (BFG) which enables flexibility in the assembly and composition of individual modules from a pool to form coupled models within CIAS, and flexibility in their deployment onto the available software and hardware resources. Such flexibility greatly enhances modellers' ability to re-configure the CIAS coupled models to answer different questions, thus tracking evolving policy needs. It also allows rigorous testing of the robustness of IA modelling results to the use of different component modules representing the same processes (for example, the economy). Such processes are often modelled in very different ways, using different paradigms, at the participating institutions. An illustrative application to the study of the relationship between the economy and the earth's climate system is provided

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