Pierre Horwitz

A review of landholder motivations and determinants for participation in conservation covenanting programmes

Conservation covenants (or easements) are flexible but legally enforceable documents attached to a land title restricting the use of that land, providing for the protection of important conservation values, while allowing the landholder to retain possession. Given the attractiveness of covenants to those who seek to expand national and regional nature conservation initiatives, it is important to understand landholder motivations for participation in programmes that covenant for nature conservation. This paper examines the likely influences on landholder decision making when it comes to conservation initiatives. A review of literature highlights key motivations and determinants, such as landholder demographics and the nature of the land tenure in question, their knowledge and awareness of the programme, financial circumstances, and perceptions of financial and other risks and benefits of the programme itself, including incentives and compensation. Underpinning, or mediating, the decision-making processes will be landholder philosophies and values, and five constructs are determined from the review, namely economic dependence on property, private property rights, confidence in perpetual covenant mechanisms, nature conservation equity and nature conservation ethic. Using these constructs, a series of explicit hypotheses is drawn, applicable to agencies dealing with conservation covenants and testable through an adaptive management approach. A conceptual model is presented to show hypothesized relationships between motivational factors and the five constructs that will lead to the uptake of covenants by landholders, providing direction for policy makers and managers of incentive programmes for nature conservation on private lands.

Wetlands as Settings for Human Health: Incorporating Ecosystem Services and Health Impact Assessment into Water Resource Management

Reconsidering the relationship between human well-being and environmental quality is central for the management of wetlands and water resources and for public health itself. We propose an integrated strategy involving three approaches. The first is to make assessments of the ecosystem services provided by wetlands more routine. The second is to adopt the “settings” approach, most developed in health promotion, wherein wetlands are one of the settings for human health and provide a context for health policies. Finally, a layered suite of health issues in wetland settings is developed, including core requirements for human health (food and water); health risks from wetland exposures; and broader social determinants of health in wetland settings, including livelihoods and lifestyles. Together, these strategies will allow wetland managers to incorporate health impact assessment processes into their decisionmaking and to examine the health consequences of trade-offs that occur in planning, investment, development, and decisionmaking outside their direct influence.

EcoHealth: A Transdisciplinary Imperative for a Sustainable Future

The time has come for a scientific journal that recognizes the inherent interdependence of the health of humans, wildlife, and ecosystems, and that provides a ‘‘gathering place’’ for those exploring the perspectives, theories, and methodologies emerging at the interface between ecological and health sciences. EcoHealth responds to this challenge and to the demands of a large and growing community of practitioners and scholars who require a high-quality, authoritative forum for reporting on research and practice that integrates human, wildlife, and ecosystem health. Health can be viewed as a central criterion for judging human sustainability (McMichael, 2002) and its understanding in this context draws on integrative and cross-disciplinary approaches involving both the ecological and health sciences. This understanding requires research on the effects of global change on ecosystem sustainability and on human health; the emergence and effects of pathogens, parasites, and pollutants within human, non-human animal, and plant communities; the interaction between environment, development, and human health; and the management of these challenges across local, regional, and global scales. In the past decade, vibrant, complementary, and overlapping research communities have emerged to address these problems, grouped under several banners, including: conservation medicine; global change and human health; and a variety of integrated studies in ecology, health, and sustainability. The common, overarching purpose of these three overlapping research domains is to better understand the connections between nature, society, and health, and how drivers of social and ecosystem change ultimately will also influence human health and well-being. The reciprocal, often complex, and even messy relationships between and among humans, other organisms, and their surroundings are clearly evident in the widening gap between those who have and those who have not, in the health effects of inequality, and in the environmental consequences of such disparities. The global loss of biological diversity affects the wellbeing of both animals and humans. Habitat destruction and species loss have led to ecosystem disruptions including the alteration of disease transmission patterns, the accumulation of toxic pollutants, and the invasion of alien species and pathogens (Aguirre et al., 2002). Conservation medicine addresses the interactions among human-induced changes in climate, habitat, biodiversity, and ecology; the emergence of pathogens, parasites, and pollutants; and health within human, non-human animal, and plant communities. This is especially relevant in today’s human-modified landscapes, where habitat destruction and degradation, and episodes of emerging human and wildlife diseases are increasing. Conservation medicine embraces participation by practitioners of ecology (terrestrial and marine), biology, epidemiology, veterinary medicine, human medicine, and public health. Perspectives from the social and political sciences are also fundamental in understanding and responding to the underlying drivers of human-induced changes in climate, habitat, and the use of terrestrial and marine ecosystems. Socio-economic change, public health initiatives, and gains in medical care have continued to improve our basic health indexes in recent decades. However, we have begun to understand that economic development can impair public health if environmental and social considerations are marginalized. Increasingly, the health of human populations is influenced by large-scale environmental changes, EcoHealth 1, 3–5, 2004 DOI: 10.1007/s10393-004-0014-9

What happens when you add salt: predicting impacts of secondary salinisation on shallow aquatic ecosystems by using an alternative-states model

Alternative-states theory commonly applied, for aquatic systems, to shallow lakes that may be dominated alternately by macrophytes and phytoplankton, under clear-water and enriched conditions, respectively, has been used in this study as a basis to define different states that may occur with changes in wetland salinity. Many wetlands of the south-west of Western Australia are threatened by rapidly increasing levels of salinity as well as greater water depths and permanency of water regime. We identified contrasting aquatic vegetation states that were closely associated with different salinities. Salinisation results in the loss of freshwater species of submerged macrophytes and the dominance of a small number of more salt-tolerant species. With increasing salinity, these systems may undergo further change to microbial mat-dominated systems composed mostly of cyanobacteria and halophilic bacteria. The effect of other environmental influences in mediating switches of vegetation was also examined. Colour and turbidity may play important roles at low to intermediate salinities [concentration of total dissolved solids (TDS) 10 000 mg L–1 TDS). The role of nutrients remains largely unquantified in saline systems. We propose that alternative-states theory provides the basis of a conceptual framework for predicting impacts on wetlands affected by secondary salinisation. The ability to recognise and predict a change in state with changes in salinity adds a further tool to decision-making processes. A change in state represents a fundamental change in ecosystem function and may be difficult to reverse. This information is also important for the development of restoration strategies. Further work is required to better understand the influence of temporal variation in salinity on vegetation states and probable hysteresis effects.

Water, ecology and health: ecosystems as settings for promoting health and sustainability

Despite the proposed ecological and systems-based perspectives of the settings-based approach to health promotion, most initiatives have tended to overlook the fundamental nature of ecosystems. This paper responds to this oversight by proposing an explicit re-integration of ecosystems within the healthy settings approach. We make this case by focusing on water as an integrating unit of analysis. Water, on which all life depends, is not only an integral consideration for the existing healthy settings (schools, hospitals, workplaces) but also highlights the ecosystem context of health and sustainability. A focus on catchments (also know as watersheds and river basins) exemplifies the scaled and upstream/downstream nature of ecosystems and draws into sharp focus the cross-sectoral and transdisciplinary context of the social and environmental determinants of health. We position this work in relation to the converging agendas of health promotion and ecosystem management at the local, regional and global scales--and draw on evidence from international initiatives as diverse as the WHO Commission on Social Determinants of Health, and the Millennium Ecosystem Assessment. Using water as a vehicle for understanding the systemic context for human wellbeing, health promotion and disease prevention draws inevitable attention to key challenges of scale, intersectoral governance and the complementary themes of promoting resilience and preventing vulnerability. We conclude by highlighting the importance of building individual and institutional capacity for this kind of integration--equipping a new generation of researchers, practitioners and decision-makers to be conversant with the language of ecosystems, capable of systemic thought and focused on settings that can promote both health and sustainability.

Water quality and macroinvertebrate response to acidification following intensified summer droughts in a Western Australian wetland

A decline in pH from ~6-8 to ~4-5 over a period of 4 years was detected during routine monitoring of surface waters at Lake Jandabup. This was accompanied by lower water levels, shorter periods of inundation and measurable changes in other attributes of the water: sulfate, iron and ammonium concentrations increased markedly, and filterable reactive phosphorus and colour (gilvin) decreased. Macroinvertebrate family richness did not change notably over this period, but there were shifts in community structure: ostracods, isopods and oligochaete worms became less abundant; amphipods, mayflies and gastropods disappeared, while ceratopogonids (Diptera) and macrothricid cladocerans increased in abundance. Historical evidence suggests that at least one other acidification event has occurred in the recent past. Mechanisms associated with the acidification, and the wetlands capacity to recover from such events, are discussed.

Distribution and conservation status of the Tasmanian giant freshwater lobster Astacopsis gouldi (Decadopa: Parastacidae)

Abstract The distribution of the Tasmanian giant freshwater lobster Astacopsis gouldi was established from two independent sources of information: taxonomically reliable observations (including collections in museums), and anecdotal information provided by fishers. Both sources depicted a disjunct distribution across northern Tasmania in northerly flowing rivers, separated by an apparent absence from one large river system. The lobster occurs up to an altitude of 390 m, but predominantly in lower reaches of rivers; it co-occurs with conspecifics in the upper, permanent regions of creeks or rivers. Concordance between distributional data sets suggests that the lobster is now absent, or much rarer, in river systems at the extremity of its distributional range, and in lower to middle reaches of other river systems. Threatening processes contributing to this decline include clearance of riparian vegetation, channelisation, pollution and fishing; the species should be regarded as threatened and appropriate reservation is recommended.

Evolution underground: A molecular phylogenetic investigation of Australian burrowing freshwater crayfish (Decapoda: Parastacidae) with particular focus on Engaeus Erichson

Phylogenetic relationships and species boundaries of Australian burrowing freshwater crayfish belonging to the genera Engaeus, Engaewa, Geocharax, Gramastacus and Tenuibranchiurus are investigated using combined mitochondrial and nuclear DNA sequence data and Bayesian and Maximum Parsimony methods. Phylogenies are statistically compared to previously published hypotheses. Engaeus, Engaewa, Geocharax, Gramastacus and Tenuibranchiurus form a strongly supported monophyletic clade. This grouping is independently supported by morphology but unites geographically highly disjunct lineages. Our data show two cryptic species in Geocharax, one cryptic species in Gramastacus and two cryptic species within the highly divergent Engaeus lyelli lineage. Using a Bayesian relaxed molecular clock method, the 16S rDNA data show generic-level diversification coinciding with the transition from a wet to arid palaeoclimate near the mid Miocene.

Peat fires and air quality: volatile organic compounds and particulates.

There are numerous localized peat deposits on the Swan Coastal Plain, an urban and rural bioregion otherwise dominated by wetland ecosystems in southwestern Australia. Hydrological change is significant in the bioregion: urban development encroaches on wetlands, groundwater extraction provides the city population with most of its water, and rainfall declines will not recharge aquifers in the future. The wetland processes which contribute to the formation of these peat deposits have therefore changed and are becoming vulnerable to fire events with residents increasingly exposed to peat smoke. There is an imperative to characterise this peat smoke to determine if exposures are harmful or toxic, and opportunities to do so in this setting arise due to the absence of bushfire smoke which has confounded other international studies. We have measured volatile organic compounds (VOCs) and particulate concentrations from an opportunistic assessment of two peat fires. SUMMA canister grab samples and a portable GCMS were used to determine the VOCs with high 1h benzene concentrations of 16 and 30 ppm v/v. PM10 and PM2.5 particulate data were collected using an Osiris continuous analyser with 24h concentrations recorded at varying time periods (within a 5 months timeframe) ranging from 1h maximums of between 23-37 microgm(-3) for PM10 and 50.5-106 microgm(-3) for PM2.5. While the 24h averages were generally below national air quality standards, elevated 1h concentrations were observed on numerous occasions and on most days. Given the proximity of residential development to many peat deposits, a drying climate and the increased risk of arson in peri-urban environments, the health impacts of exposure to peat smoke need to be determined and if necessary measures developed to prevent exposure (which would include maintaining wetland sediment integrity so as to reduce its vulnerability to fire).

Beyond Disciplinary Boundaries: Leptospirosis as a Model of Incorporating Transdisciplinary Approaches to Understand Infectious Disease Emergence

Leptospirosis is a zoonotic infectious disease of global significance. Political, economic, demographic, ecologic, and other anthropogenically driven environmental changes have fueled the reemergence of this disease in industrialized and developing countries, and in both urban and rural settings. We argue that conventional disciplinary, even interdisciplinary, research methods are not sufficient to elucidate the complex mechanisms and causal relationships among the myriad factors responsible for infectious disease emergence. To address the significant gaps in the field of leptospirosis, an integrated research agenda is needed to guide successful public health remediation of the disease. Based on both working group analysis of literature and newly obtained information, we describe cross-disciplinary collaborative approaches that allow a novel approach to understand leptospirosis emergence with regard to mountain-to-sea ecosystems in Hawai‘i and other region-specific ecosystems. Leptospirosis research is a model for how complementary disciplines in the social, cultural, ecological, and biomedical sciences can optimally interact towards a higher understanding of emerging infectious diseases.