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A detailed pollen record from the Ocean Drilling Program Site 820 core, located on the upper part of the continental slope off the coast of northeast Queensland, was constructed to compare with the existing pollen record from Lynch's Crater on the adjacent Atherton Tableland and allow the production of a regional picture of vegetation and environmental change through the last glacial cycle. Some broad similarities in patterns of vegetation change are revealed, despite the differences between sites and their pollen catchments, which can be related largely to global climate and sea-level changes. The original estimated time scale of the Lynch's Crater record is largely confirmed from comparison with the more thoroughly dated ODP record. Conversely, the Lynch's Crater pollen record has assisted in dating problematic parts of the ODP record. In contrast to Lynch's Crater, which reveals a sharp and sustained reduction in drier araucarian forest around 38,000 yrs BP, considered to have been the result of burning by Aboriginal people, the ODP record indicates, most likely, a stepwise reduction, dating from 140,000 yrs BP or beyond. The earliest reduction shows lack of a clear connection between Araucaria decline and increased burning and suggests that people may not have been involved at this stage. However, a further decline in araucarian forest, possibly around 45,000 yrs BP, which has a more substantial environmental impact and is not related to a time of major climate change, is likely, at least partially, the result of human burning. The suggestion, from the ODP core oxygen isotope record, of a regional sea-surface temperature increase of around 4 degrees C between about 400,000 and 250,000 yrs BP, may have had some influence on the overall decline in Araucaria and its replacement by sclerophyll vegetation. (C) 2000 Elsevier Science B.V. All rights reserved.

Coastal communities in Pacific Island Countries are particularly vulnerable to climate change impacts including sea-level rise, coastal erosion, tidal inundation, and the intensification of storm surge activity. In response, adaptation projects across the region have attempted to reduce exposure and overall vulnerability to these coastal pressures. This paper explores what happens once these projects reach communities: are effective and sustainable outcomes achieved, or can the implementation of adaptation projects lead to unintended negative outcomes and result in maladaptation? This paper investigates this issue in relation to two seawall projects implemented in communities on Vanua Levu Island, Fiji. We found that the seawalls have not been successful in achieving their primary aim of safeguarding communities against coastal pressures and have instead resulted in unanticipated negative outcomes for land and livelihood security. Of primary concern is the way that seawalls trap water along their landward sides—acting more like a dam—because of the ineffective design and construction of the seawalls and associated infrastructure. This paper concludes with a call to think more long-term about site-specific adaptation measures that actively involve and are driven by local perspectives in the planning, implementation, and maintenance process.

Soil organic carbon (SOC) represents a significant pool of carbon within the biosphere. Climatic shifts in temperature and precipitation have a major influence on the decomposition and amount of SOC stored within an ecosystem. We have linked net primary production algorithms, which include the impact of enhanced atmospheric CO2 on plant growth, to the Soil Organic Carbon Resources And Transformations in EcoSystems (SOCRATES) model to develop a SOC map for the North Central Region of the United States between the years 1850 and 2100 in response to agricultural activity and climate conditions generated by the CSIRO Mk2 Global Circulation Model (GCM) and based on the Intergovernmental Panel for Climate Change (IPCC) IS92a emission scenario. We estimate that the current day (1990) stocks of SOC in the top 10 cm of the North Central Region to be 4692 Mt, and 8090 Mt in the top 20 cm of soil. This is 19% lower than the pre-settlement steady state value predicted by the SOCRATES model. By the year 2100, with temperature and precipitation increasing across the North Central Region by an average of 3.9°C and 8.1 cm, respectively, SOCRATES predicts SOC stores of the North Central Region to decline by 11.5 and 2% (in relation to 1990 values) for conventional and conservation tillage scenarios, respectively.

Rapid urbanization, improved quality of life, and diversified lifestyle options have collectively led to an escalation in housing demand in our cities, where residential areas, as the largest portion of urban land use type, play a critical role in the formation of sustainable cities. To date there has been limited research to ascertain residential development layouts that provide a more sustainable urban outcome. This paper aims to evaluate and compare sustainability levels of residential types by focusing on their layouts. The paper scrutinizes three different development types in a developing country context—i.e., subdivision, piecemeal, and master-planned developments. This study develops a “Neighborhood Sustainability Assessment” tool and applies it to compare their sustainability levels in Ipoh, Malaysia. The analysis finds that the master-planned development, amongst the investigated case studies, possesses the potential to produce higher levels of sustainability outcomes. The results reveal insights and evidence for policymakers, planners, development agencies and researchers; advocate further studies on neighborhood-level sustainability analysis, and; emphasize the need for collective efforts and an effective process in achieving neighborhood sustainability and sustainable city formation.

Recently published green infrastructure, nature-based solutions, and ecosystem disservices (ED) literature have focused primarily on the supply of urban regulating and cultural ecosystem services (ES). Other literature on urban and peri-urban agriculture has mostly studied the role of localized, intensive agricultural practices in providing food to inhabitants. The aim of this review is to raise awareness and stress the knowledge gap on the importance of urban provisioning ES, particularly when implementing an edible green infrastructure (EGI) approach as it can offer improved resilience and quality of life in cities. We compiled and systematically analyzed studies on urban ES and ED related to a number of EGI typologies. Our systematic review of the relevant literature via an EGI framework, identified more than 80 peer-reviewed publications that focused on ES and food production in urban areas. An EGI approach can contribute socially, economically, and environmentally to urban sustainability and food security. However, such benefits must be weighed against ED trade-offs, including: potential health risks caused by human exposure to heavy metals and organic chemical contaminants often present in urban surroundings. We conclude with recommendations and guidelines for incorporating EGI into urban planning and design, and discuss novel areas for future research.

Abstract Purpose The reduction of the greenhouse gas nitrous oxide (N2O) to dinitrogen (N2) via denitrification and N2O source partitioning between nitrification and denitrification remain major uncertainties in sugarcane systems. We therefore investigated magnitude and product stoichiometry of denitrification and production pathways of N2O from a tropical sugarcane soil in response to increasing soil nitrate (NO3−) availability. Methods Microcosms were established using a tropical sugarcane soil (Qld, Australia) and emissions of N2O and N2 were measured following fertilisation with 15NO3−–N equivalent to 25, 50 and 100 μg N g−1 soil, simulating soil NO3− contents previously observed in situ, and mimicking flood irrigation by wetting the soil close to saturation. Results Cumulative N2O emissions increased exponentially with NO3− availability, while cumulative N2 emissions followed an exponential increase to maximum. Average daily N2 emissions exceeded 5 µg N2–N g soil−1 and accounted for > 99% of denitrification. The response of N2O suggests preferential NO3− reduction with increasing NO3− availability, increasing N2O even when NO3− levels had only a diminishing effect on the overall denitrification rate. The fraction of N2O emitted from denitrification increased with NO3− availability, and was a function of soil water, NO3− and heterotrophic soil respiration. Conclusions Our findings show the exponential increase of N2O driven by excess NO3−, even though the complete reduction to N2 dominated denitrification. The low N2O/(N2O + N2) product ratio questions the use of N2O as proxy for overall denitrification rates, highlighting the need for in-situ N2 measurements to account for denitrification losses from sugarcane systems.

SummaryPolyhydroxybutyrate (PHB) is a naturally occurring bacterial polymer that can be used as a biodegradable replacement for some petrochemical‐derived plastics. Polyhydroxybutyrate is produced commercially by fermentation, but to reduce production costs, efforts are underway to produce it in engineered plants, including sugarcane. However, PHB levels in this high‐biomass crop are not yet commercially viable. Chemical ripening with herbicides is a strategy used to enhance sucrose production in sugarcane and was investigated here as a tool to increase PHB production. Class A herbicides inhibit ACCase activity and thus reduce fatty acid biosynthesis, with which PHB production competes directly for substrate. Treatment of PHB‐producing transgenic sugarcane plants with 100 μm of the class A herbicide fluazifop resulted in a fourfold increase in PHB content in the leaves, which peaked ten days post‐treatment. The minimum effective concentration of herbicide required to maximize PHB production was 30 μm for fluazifop and 70 μm for butroxydim when applied to saturation. Application of a range of class A herbicides from the DIM and FOP groups consistently resulted in increased PHB yields, particularly in immature leaf tissue. Butroxydim or fluazifop treatment of mature transgenic sugarcane grown under glasshouse conditions increased the total leaf biomass yield of PHB by 50%–60%. Application of an ACCase inhibitor in the form of a class A herbicide to mature sugarcane plants prior to harvest is a promising strategy for improving overall PHB yield. Further testing is required on field‐grown transgenic sugarcane to more precisely determine the effectiveness of this strategy.

Climate change is affecting biodiversity worldwide inducing species to either “move, adapt or die”. In this paper we propose a conceptual framework for analysing range shifts, namely a catalogue of the possible patterns of change in the distribution of a species along elevational or other environmental gradients and an improved quantitative methodology to identify and objectively describe these patterns. Patterns are defined in terms of changes occurring at the leading, trailing or both edges of the distribution: (a) leading edge expansion, (b) trailing edge retraction, (c) range expansion, (d) optimum shift, (e) expansion, (f) retraction, and (g) shift. The methodology is based on the modelling of species distributions along a gradient using generalized additive models (GAMs). Separate models are calibrated for two distinct periods of assessment and response curves are compared over five reference points. Changes occurred at these points are formalized into a code that ultimately designates the corresponding change pattern. We tested the proposed methodology using data from the Swiss national common breeding bird survey. The elevational distributions of 95 bird species were modelled for the periods 1999–2002 and 2004–2007 and significant upward shifts (all patterns confounded) were identified for 35% of the species. Over the same period, an increase in mean temperature was registered for Switzerland. In consideration of the short period covered by the case study, assessed change patterns are considered to correspond to intermediate patterns in an ongoing shifting process. However, similar patterns can be determined by habitat barriers, land use/land cover changes, competition with concurrent or invasive species or different warming rates at different elevations.