The concepts of planetary boundaries are influential in the sustainability literature and assist in delineating the ‘safe operating spaces’ beyond which critical Earth system processes could collapse. Moving away from our current trajectory towards ‘hothouse Earth’ will require knowledge of how Earth systems have varied throughout the Holocene, and whether and how far we have deviated from past ranges of variability. Such information can inform decisions about where change could be resisted, accepted or where adaptation is inevitable. The need for information on long-term (Holocene) change provides an interface for palaeoecology and sustainability that remains underexploited. In this position paper, we explore this interface, first discussing the need for long-term perspectives and introducing examples where palaeoecology has been used in defining safe operating spaces and constraining limits of acceptable change. We describe advances in quantitative methods for analysis of time-series data that strengthen the contribution of palaeoecology to the concepts of planetary boundaries and safe operating spaces. We consider the importance of issues of scaling from landscape to regional and global scales in operationalising planetary boundaries concepts. We distil principles for this field of research going forward and introduce three case studies which will form the basis of research on these topics.

Humanity has exceeded sustainability boundaries for factors that sustain aquatic ecosystems and so society is operating outside Safe Operating Spaces: those within which society has evolved over the long term. Our inland waterways have suffered through loss and degradation through the industrial revolution. The degree of biodiversity loss in inland waterways exceeds that of the oceans and the land and freshwater vertebrates are at great risk of extinction. The Ramsar Convention was established to arrest the loss and degradation of the world's most significant wetlands. While the Convention has been effective in slowing this trajectory many wetlands have been lost or degraded since it was signed in 1971. The UN Decade of Restoration calls on nations to work to allow our ecosystems to recover from the impacts of industrialised people. This goal require us to identify desirable ecosystem states that act as targets for management. By characterising past, natural variability we can see the planetary boundaries we have exceeded, envision the factors that need addressing and acknowledge the magnitude of the challenge to return to sustainable states. The Society for Ecological Restoration identifies 'appropriate native baseline' as a target for restoration measures. This past condition of our inland waterways is readily identifiable through historical approaches including through paleolimnological techniques. The recognition of this past state is essential in assisting us to rebuild ecosystem resilience in the pursuit of a sustainable future within Planetary Boundaries.

Like nature’s diary, sediment cores record an ecosystem’s history layer by layer, preserving information on past climates, ecological changes, and human activities. These time capsules reveal environmental shifts over thousands of years through fossils like diatoms, single-celled algae that serve as powerful bioindicators of water quality. Diatoms are sensitive to changes in salinity, pH, and nutrient levels and provide insights into past and present aquatic conditions. Changes in species composition within sediment layers highlight ecological transitions, while chemical signals, such as heavy metals and nutrient levels, trace human impacts like industrialization and agriculture. Radiocarbon dating and isotopic techniques establish a timeline of these events, offering guidance for future ecosystem management. Mangrove ecosystems in Demak, Central Java, have faced severe degradation since the 1980s due to agricultural and aquaculture expansion, leading to coastal abrasion. Rehabilitation efforts since 2012 have supported natural regrowth, gradually restoring these critical habitats. This study focuses on Bedono Village, analyzing land-use changes, diatom distribution, and sediment records to understand environmental shifts and promote sustainable coastal management. Diatom analysis revealed freshwater species dominance (49

Lake Balekambang is a water area formed by volcanic activity located in the Dieng Plateau. The lake is facing a threat in the form of sedimentation, so it's important to identify protists to help control the sedimentation and understand the organisms that make up the lake's ecosystems. One efficient method is using environmental DNA (eDNA) to analyze microscopic organisms. In this study, eDNA samples were collected from the lake's sediments and then extracted using the ZymoBIOMICS Fecal/Soil Microbe Miniprep kit. PCR amplification was performed using an 18S rRNA primer, followed by sequencing using Next Generation Sequencing (NGS). Bioinformatic analysis with QIIME 2 and RSTUDIO revealed 14,630 reads, including 179 Amplicon Sequence Variants (ASVs), all belonging to Eukaryotes. The analysis identified 21 families of protists in Lake Balekambang, with 16 families found in both sample locations and 9 families unique to each location, with 4 families common to both. The Diversity Index (H') was calculated to be 4.5 and 3.5, indicating high community diversity and environmental stability, while the Dominance Index (C) values of 0.03 and 0.08 suggest a low level of dominance within the ecosystem.

Mangroves are an important coastal ecosystem in the global cycle of carbon and climate change mitigation. Unfortunately, a significant loss of mangrove forests has significantly increased carbon emissions over recent years. This research aims to measure the carbon stocks and potential carbon storage of the Tuntang Estuary mangrove forest. Sixteen quadrant plots at six sites were used to collect data on above- and below-ground carbon (roots and sediment). Several published allometric formulas were used for estimating the above and below-ground (root) carbon, while the Walkley and Black method was used to analyze sediment organic carbon. This study showed that the potential of total carbon stocks in this mangrove forest was approximately 0.08 × 106 (± 0.02) Mg C or equivalent to 0.29 × 106 (± 0.05) Mg CO2e. The largest average percentage of carbon stocks (62

Mitigating climate change while safeguarding biodiversity and livelihoods is a major challenge. However, rampant afforestation threatens biodiversity and livelihoods, with questionable benefits to carbon storage. The narrative of landscape degradation is often applied without considering the history of the landscape. While some landscapes are undoubtedly deforested, others existed in open or mosaic states before human intervention, or have been deliberately maintained as such. In psychology, a 'fundamental attribution error' is made when characteristics are attributed without consideration of context or circumstances. We apply this concept to landscapes, and then propose a process that avoids attribution errors by testing a null hypothesis regarding past forest extent, using palaeoecology and other long-term data, alongside ecological and stakeholder knowledge.

Ecological and statistical models were developed using freshwater algal assemblages to assess water quality and ecological health of a regulated river. These models were used to inform configuration of flows to maintain or improve environmental conditions of the waterway whilst meeting consumptive water supply commitments. The flow regime of the MacKenzie River, western Victoria, Australia, has been substantially modified since the construction of a water supply reservoir on its upper reach in 1887. Water is withdrawn at several locations downstream of the reservoir, creating a substantially modified flow regime, impacting key environmental values of the river. To assess the impact of the different flow regimes on river health and ecosystem function, ten sites were repeatedly sampled along the river between February 2012 and April 2014. Physical and chemical characteristics of water, including pH, temperature, turbidity, electrical conductivity, dissolved oxygen, total nitrogen, total phosphorous, cations, and anions, were measured. Biological properties of the algal periphyton communities, including dry mass, ash-free dry mass, chlorophyll- a concentration, and species composition, were also measured. Exploration of the algal assemblage and water chemistry data using the computationally unconstrained ordination technique such as principal component analysis principal component analysis (PCA), correspondence analysis (CA), detrended correspondence analysis (DCA), and canonical correspondence analysis (CCA) indicated two strong gradients in the data sets. Furthermore, the quantitative ecosystem response models have been developed as the prototype tool to assist in the future configuration of flows in this river. The empirical data and models showed the lower reaches of the river to be in poor condition under low flows, but this condition improved under flows of 35 ML/day, as indicated by the reduction in green algae and cyanobacteria and improvement. Finally, the results are presented to tailor discharge and duration of water volume by amalgamation of consumptive and environmental flows to improve the condition of the stream thereby supplementing the flows dedicated to environmental outcomes.

Mangrove ecosystems can absorb significant amounts of carbon and help mitigate climate change. However, their existence continues to be endangered by natural and human forces. Therefore, mangrove restoration is regarded as a crucial component of the global climate change agenda. This study aims to estimate the potential total carbon stock of restored mangrove ecosystems in Pasarbanggi, Rembang, Central Java. The above-below-ground (root) carbon stock was calculated using several published allometric equations. The loss-on-ignition method analyzed leaf litter and sediment carbon stocks. This study estimates the Pasarbanggi mangrove ecosystem's total carbon stock potential at 0.02 × 106 MgC, which is equivalent to the potential CO2 emission of 0.08 × 106 MgCO2e, with up to 65% stored in sediments. This study highlights the critical role of restored mangrove ecosystems on the climate change mitigation agenda by reducing the concentration of atmospheric CO2.

Wetlands provide a wealth of ecosystem services to people, including ecological, economic, and socio-cultural benefits. However, more than 30% of freshwater species are threatened with extinction, and freshwater biodiversity is declining faster than that observed in oceans or forests. When it comes to the management of wetlands, it often occurs too late and when ecosystem services to people are at risk of being lost. It is easy to observe and monitor the recent impacts of people on wetland systems, but the changes we see today are a product of hundreds, even thousands of years of direct and indirect human impact. Without a deeper understanding of the long-term context of human impacts on wetland systems, it is impossible to manage the problems they experience (such as changes in hydrology, nutrient loading, acidification, and salinisation). Despite the 20th century being the period in which humans have exerted the greatest impact on wetland systems, it was also the period in which we developed a greater appreciation of wetlands as anthropogenically altered landscapes, and, maybe paradoxically, the benefits that accrue from healthy wetlands. Palaeolimnological approaches allow an understanding of wetland system variability over millennial scales, providing background context for anthropogenically forced change. This palaeo-perspective enables a deeper understanding of the long-term context of human impacts on wetland systems and can provide a fresh perspective when managing impacted systems.

Predicted increases in fire frequency and extent are being realised across Australia, bringing changes to the fire regime which may influence the availability of essential resources required by birds. However, few studies have examined either the impacts of fire frequency on birds or the impacts from both wildfire and planned burns, com bined. Birds were surveyed eight times across 84 sites in heathy dry forests in central Victoria, south-east Australia, from 2012 to 2014. Fire history records were retrieved from the 1970's onwards, the time from which accurate planned burn records were kept. We developed mixed models to investigate how birds responded to time-since-fire and fire frequency, analysing total bird abundance, ten foraging guilds and 30 individual species. We found distinct responses by all modelled guilds and species to time-since-fire, along with evidence for responses to fire frequency. The greatest shifts in species' abundances occurred during the first ten years post fire, with bird species commonly present across the stages greater than ten years since fire. For total bird abundance there was no statistically detectible difference between recently burnt forest (0-6 months) and other age classes. However, some guilds showed a significant drop in abundance in newly burnt vegetation (e.g. bark foragers, damp ground insectivores, those that feed on seeds close to the ground, tall shrub foragers). It is with guild and species' responses that more differences across vegetation age classes became apparent. Significant increases in abundance were apparent in both the regrowth and new growth vegetation age classes, compared with older habitat (e.g. canopy foragers, damp ground insectivores, tall shrub foragers); open ground foragers were espe-cially common in post-fire regrowth but then significantly declined. Other responses were more complex, with species' preferences reflecting their foraging ecology. Some birds showed preferences across two age classes: sites that were young post-fire regrowth (6 months-2.5 years since fire) along with sites of old habitat (>35 years since fire), (e.g. Crimson Rosella, Scarlet Robin, Sulphur-crested Cockatoo), while some ground-foraging species became scarce in dense new-growth vegetation that appears 2.5-10 years post fire (e.g. Australian Magpie, Laughing Kookaburra and White-winged Chough). Such species may deserve specific management strategies to maintain populations in forests where substantial areas are burnt by wildfire or planned burns, over short periods of time. The model for total bird abundance showed a significant fire frequency response with birds preferring sites twice burnt within 35 years (e.g. bark and canopy-foraging guilds). Four guilds demonstrated a preference for sites frequently burnt, increasing in abundance as number of burns increased (nectarivores, open-ground foragers, seeds in trees foragers, tall shrub foragers). In contrast, two species appeared to prefer sites that had experienced low fire frequencies, a response not common to their guilds. Laughing Kookaburra (carnivore) and White-winged Chough (forages on open ground among trees) generally declined in abundance with increasing fire frequency.

The Ramsar Convention on the conservation and wise use of the World's wetlands was agreed in response to widespread recognition of the declining condition of wetlands and the impact of this on wetland habitats and associated fauna. Since 1971, over 2000 wetlands have been listed as internationally important by 172 countries and covering more than 2,000,000 km2. There have been considerable advances in the scientific understanding of wetlands, and today, the monitoring of these systems draws on multiple disciplinary approaches. The Convention itself has responded to these advances and the ongoing challenge to conserve the world's wetlands. Importantly, signatory nations regularly report on the condition of wetlands, update listings, and have adopted a framework to ensure wise use of all wetlands. In turn, healthy wetlands are increasingly seen to afford considerable ecosystem services to human communities that rely on them for the provision of food and water and recreation and for their cultural and aesthetic values. Whilst the Convention has now passed its 50th anniversary, it is increasingly recognised that wetlands continually change over many time scales and that direct human pressures are merely one of the drivers that affect wetlands. The monitoring of these changes continues to allow the Convention and signatory nations to amend the framework to reflect emerging understanding of wetland change. These advances enable the Convention to encourage, and better allow, signatory nations to pursue social and economic outcomes whilst continuing to contribute to the pursuit of conserving the natural assets accommodated within the global network of significant wetlands.

Click to increase image sizeClick to decrease image size Disclosure statementNo potential conflict of interest was reported by the author(s).

Mangrove ecosystems have many functions for coastal areas, including ecological, social, and economic services. These functions have a systemic impact on the environment of other coastal ecosystems and human life. The mangrove ecosystem covering an area of 197.92 ha in Bedono, Demak Regency, Central Java was threatened due to the wave abrasion and high tides. Some parts of Bedono Village had become inundated and flooded permanently, zink as part of the ocean. This research was conducted to quantify water pollution in the mangrove ecosystem of Bedono Village using the Storage and Retrieval (STORET) method and the pollution index (PI). The fieldwork was conducted June 2022, by collecting water samples for laboratory analysis tests and in-situ water quality measurement. The parameter of the water quality that exceeded threshold of the Government Regulation of the Republic of Indonesia Number 22 of 2021 are the dissolved oxygen (DO) ranges between 4.39-8.78 mg L-1, BOD ranges between 30-32.4 mg L-1, phosphate ranges between 0.063-0.074 mg L-1, ammonia ranges between 0.148-0.48 mg L-1, Cr ranges between 0.071-0.21 mg L-1, and Pb ranges between 0.071-0.21 mg L-1. Based on the STORET method, the water quality in the mangrove ecosystem was found to be in the category of moderately (-16, for harbor function) - heavily polluted (-80, for tourism and-90, marine biota), whereas based on the PI index it was lightly polluted (1.77-4.12, for harbor function) - moderately polluted (11.06-13.83for tourism, and 9.96-11.85, marine biota).

AbstractEcological and statistical models were developed using freshwater algal assemblages to assess water quality and ecological health of a regulated river. These models were used to inform configuration of flows to maintain or improve environmental conditions of the waterway whilst meeting consumptive water supply commitments. The flow regime of the MacKenzie River, western Victoria, Australia, has been substantially modified since the construction of a water supply reservoir on its upper reach in 1887. Water is withdrawn at several locations downstream of the reservoir, creating a substantially modified flow regime, impacting key environmental values of the river. To assess the impact of the different flow regimes on river health and ecosystem function, ten sites were repeatedly sampled along the river between February 2012 and April 2014. Physical and chemical characteristics of water, including pH, temperature, turbidity, electrical conductivity, dissolved oxygen, total nitrogen, total phosphorous, cations and anions were measured. Biological properties of the algal periphyton communities, including dry mass, ash-free dry mass, chlorophyll-aconcentration and species composition were also measured. Exploration of the algal assemblage and water chemistry data using the computationally unconstrained ordination technique such as principal component analysis principal component analysis (PCA), correspondence analysis (CA), detrended correspondence analysis (DCA) and canonical correspondence analysis (CCA) indicated two strong gradients in the data sets. Furthermore, the quantitative ecosystem response models have been developed as the prototype tool to assist in the future configuration of flows in this river. The empirical data and models showed the lower reaches of the river to be in poor condition under low flows, but this condition improved under flows of 35 ML/day, as indicated by the reduction in green algae and cyanobacteria and improvement. Finally, the results are presented to tailor discharge and duration of water volume by amalgamation of consumptive and environmental flows to improve the condition of the stream thereby supplementing the flows dedicated to environmental outcomes.

The Earth has been subjected to cyclical climatic variations that are attributable to a range of forces that have return times ranging from days to many millennia. Most of the world’s wetlands were formed since the last glaciation, yet they have varied greatly in condition even through the relatively stable climates of the Holocene. Many wetlands listed under the Ramsar Convention have experienced conditions that are different than those observed at the time they were listed. Cyclical changes that drive natural variation will continue to influence wetlands. These natural drivers, however, will combine with anthropogenic influences that will alter the natural ecological character. As many wetlands change, Ramsar reporting will be faced with assessing changes in condition and accommodating the expectations of nations to provide guidance that can help manage these driving forces.

Across time society has been confronted with a wide range of crises that have required measured responses. The COVID-19 pandemic was widely forecast, but governmental preparation was lacking. Even when it was spreading, its risks to society were downplayed in some quarters. The climate change crisis has also been widely forecast, and preparation has been slow, with vested interests also denying the science or downplaying the risk. The pandemic is an acute crisis with rapid onset and highly visible impacts on human life and wellbeing. Through vaccine technology, however, there is a short term and likely effective management measure available. Climate change is a diffuse crisis with long lead times. In contrast to Covid, it has momentum and, once thresholds are exceeded, measures to reverse the change will have limited effectiveness. While the implications of carbonising our atmosphere were known over 50 years ago, the socio-economic response is only now taking hold. The slow nature of this crisis has subdued the political response, and the Earth is now committed to considerable impacts, even if we collectively act decisively now. The gradual nature of this crisis, its opaque direct impacts on humanity, and the scale of its complexity render it a 'wicked' problem that will persist through this century and beyond. Scenarios of impact across multiple quarters assure us that the costs of unabated climate change will result in a global scale crisis, played out in many individual locations for many decades. Aware of this, society is already investing in adapting to the changes that are foreseen while also beginning the process of mitigating carbon emissions to limit the scale of the challenge. In some places, this may mean preparing economies for drier climates, while in others, it may mean a managed retreat from the present coastline. Providing refuge from heatwaves will be a widespread adaptation measure. For nature, its capacity to adapt will be strengthened if the pressure from humans is also mitigated. © 2023 Author(s).

The effective management of wetlands requires a sound policy foundation that recognises the full range of states through which a wetland may pass, the drivers of change and their periodicity, and the trajectory of present change relative to past conditions. A management plan should suit the local requirements, and be as large or complex as is required for any specific site. While the format and presentation of a management plan can vary, the process comprises six steps to implement actions to achieve the management goals, namely: Why are we here? What have we got? What are the important features? What are the important influences? What do we want? What must we do? Based on general requirements for effectiveness tracking in protected areas, a specific Ramsar Site Management Effectiveness Tracking Tool (R-METT) has been formally adopted by the Ramsar Convention. This is designed to be simple and rapid to assist site managers and to facilitate wide uptake of the approach. The evaluation questions in R-METT were designed to be easily answered by the management authority without any additional research or intense and costly data collection.

Wetlands worldwide are in trouble. Their area and condition have been, and are, in continuing decline. Through drainage and conversion to other land uses, the area of natural wetlands is decreasing, although the extent of losses is uncertain: since 1700 AD loss is likely to be less than 87% but more than 21%–36%. Although more wetlands are currently reported to be in good than poor ecological character state, more are deteriorating than improving in state, and deterioration is becoming increasingly widespread. There continue to be challenges in making quantitative assessments of wetland state and trends in state, including in defining baseline and reference conditions. Longer-term palaeoecological records can help separate change from variation, and inform establishing appropriate baselines for wetland assessment and management.

In the face of global-scale decline in the extent and state of the world's wetlands, the Ramsar Convention has mobilised most of the world's nations to support the conservation and wise use of wetlands. Whilst wetlands continue to be lost and their condition overall continues to decline, the Convention has played a significant part in assisting nations to mitigate pressures and preserve values and ecological assets. The pressures on wetlands will continue, and the Convention could continue its valuable contribution by increasing the awareness of the value of, and risks to wetlands, assisting Contracting Parties to plan for and accommodate change in wetland state, including that driven by climate change, recognising wetlands as socio-ecological systems, and refining the practice of wetland restoration. There remains much opportunity to extend the technical and management capacity that can be catalysed by the Convention to all nations to address the conservation and wise use of wetlands across the globe.