Going with the flow: global warming and the challenge of sustaining river ecosystems in monsoonal Asia

River ecosystems in monsoonal Asia are experiencing human impacts to the detriment of the rich biodiversity they support. Threats include hydrologic alteration, pollution, habitat destruction, overexploitation, and invasive exotic species. Global warming will cause further changes to river ecosystems, and may act synergistically with other threat factors. Significant upward or northward range adjustments by the freshwater biota will be necessary to cope with rising temperatures, but there will be significant constraints upon dispersal ability and availability of suitable habitat for many organisms. Global warming will exacerbate existing impacts of hydrologic alteration because of the adaptive human responses that will be engendered by changes in climate and runoff, particularly dams constructed for hydropower generation, flood protection, water storage, and irrigation. The consequences of further hydrologic alteration and habitat fragmentation will be profound, since almost all ecological processes, material transfers and life-cycle events in the rivers of monsoonal Asia are mediated or controlled by flow. Thus a change in the timing or amounts of flow changes everything. Collaborative research to determine the environmental allocation of water flow needed to maintain ecosystem integrity and sustain biodiversity in the human-dominated rivers of monsoonal Asia should be a priority for ecologists, engineers and water-resource managers.

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Strategies for Restoring River Ecosystems: Sources of Variability and Uncertainty in Natural and Managed Systems

Strategies for Restoring River Ecosystems: Sources of Variability and Uncertainty in Natural and Managed Systems ◽

10.47886/9781888569469.ch4 ◽

2003 ◽

Keyword(s):

Land Uses ◽

Ecological Processes ◽

Human Actions ◽

Ecosystem Integrity ◽

River Ecosystems ◽

Natural Processes ◽

Societal Needs ◽

Hydrologic Regimes ◽

Restoration Strategies ◽

Landscape Scales

<em>Abstract</em>.—River ecosystem integrity is evaluated within a variety of landscape scales. We examine influences of variations in natural processes and human actions on river ecosystems and propose a concept for restoring impaired systems. The ecological structure and function of rivers vary across a hierarchy of landscape scales with different spatial and temporal dimensions. The major linkages within river systems include exchange of water and materials along longitudinal connections from streams to rivers, lateral connections between river and floodplain systems, and vertical surface and subsurface (hyporheic) water exchanges. Strong longitudinal linkages dominate confined river reaches while unconfined floodplain reaches show strong affinities for lateral and vertical exchange. A landscape concept, “the shifting habitat mosaic” (SHM), provides a framework for understanding how these interactions create and maintain the physical and ecological diversity of habitats, biotic communities, and ecosystem integrity. While each river system has unique physical and ecological characteristics, many human actions and ecological effects can be expressed within the SHM concept. For example, societal needs for power generation, transportation, water management, and land uses (e.g., urban and agricultural) often alter natural processes of hydrologic regimes and material transport and deposition. These factors affect interactions between the river channel and the surrounding river–riparian corridor. Restoration strategies can apply the SHM concept by focusing on restoring normative variations to processes (e.g., hydrologic regimes) that contribute to ecosystem integrity. Management practices (e.g., dam hydrologic regimes, flood control facilities, levees, land uses) can be modified to restore natural physical and ecological processes (e.g., thermal regimes, water exchange, and animal migrations).

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Challenges and Opportunities for Terrapene carolina carolina Under Different Climate Scenarios

Remote Sensing ◽

10.3390/rs12050836 ◽

2020 ◽

Vol 12 (5) ◽

pp. 836

Author(s):

Amanda K. Martin ◽

Karen V. Root

Keyword(s):

Protected Areas ◽

Human Impacts ◽

Global Climate ◽

Large Population ◽

The United States ◽

Dispersal Ability ◽

Suitable Habitat ◽

Population Declines ◽

Terrapene Carolina ◽

Terrapene Carolina Carolina

An unprecedented rate of global climate change as a result of human impacts has affected both endotherms and ectotherms. This is of special concern for ectotherms, such as reptiles, as these species are suffering from large population declines and lack the dispersal ability of other taxa. There are many protected areas across the United States; however, these areas are fragmented, which hinders dispersal. We examined species distribution and dispersal capabilities for Terrapene carolina carolina, a relatively narrow range, low dispersal, and vulnerable species. We created climatic suitability models to predict changes in suitable habitat and identified important predictor variables. We modeled three time periods using MaxEnt and hypothesized that there would be an increase in northern habitat. We found that most of the suitable habitat changed at the northern end of the range and that mean temperature of driest quarter had the most influence on future predictions. Overall there were relatively moderate changes in suitable habitat, but where these changes occur affects accessibility. As an example, we examined these local scale movements within Oak Openings Region and found that individuals are capable of dispersing to new suitable habitats; however, other physical barriers will hinder movements. In conclusion, there is a critical need to protect this vulnerable reptilian species and our results suggest that T. c. carolina will expand their distribution northward. We suggest that land managers increase connectivity among protected areas to facilitate dispersal, but future studies should incorporate other dynamic ecological factors at finer spatial scale.

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The Impact of Human Pressure and Climate Change on the Habitat Availability and Protection of Cypripedium (Orchidaceae) in Northeast China

Plants ◽

10.3390/plants10010084 ◽

2021 ◽

Vol 10 (1) ◽

pp. 84

Author(s):

Huanchu Liu ◽

Hans Jacquemyn ◽

Xingyuan He ◽

Wei Chen ◽

Yanqing Huang ◽

...

Keyword(s):

Climate Change ◽

Northeast China ◽

Habitat Destruction ◽

Changbai Mountains ◽

Suitable Habitat ◽

Human Pressure ◽

Terrestrial Orchids ◽

The Future ◽

Suitable Habitats ◽

The Impact

Human pressure on the environment and climate change are two important factors contributing to species decline and overall loss of biodiversity. Orchids may be particularly vulnerable to human-induced losses of habitat and the pervasive impact of global climate change. In this study, we simulated the extent of the suitable habitat of three species of the terrestrial orchid genus Cypripedium in northeast China and assessed the impact of human pressure and climate change on the future distribution of these species. Cypripedium represents a genus of long-lived terrestrial orchids that contains several species with great ornamental value. Severe habitat destruction and overcollection have led to major population declines in recent decades. Our results showed that at present the most suitable habitats of the three species can be found in Da Xing’an Ling, Xiao Xing’an Ling and in the Changbai Mountains. Human activity was predicted to have the largest impact on species distributions in the Changbai Mountains. In addition, climate change was predicted to lead to a shift in distribution towards higher elevations and to an increased fragmentation of suitable habitats of the three investigated Cypripedium species in the study area. These results will be valuable for decision makers to identify areas that are likely to maintain viable Cypripedium populations in the future and to develop conservation strategies to protect the remaining populations of these enigmatic orchid species.

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Spatiotemporal Variability in Extreme Precipitation in China from Observations and Projections

Water ◽

10.3390/w10081089 ◽

2018 ◽

Vol 10 (8) ◽

pp. 1089 ◽

Cited By ~ 9

Author(s):

Yifeng Peng ◽

Xiang Zhao ◽

Donghai Wu ◽

Bijian Tang ◽

Peipei Xu ◽

...

Keyword(s):

Global Warming ◽

Extreme Precipitation ◽

Spatiotemporal Variability ◽

Tibet Plateau ◽

Cmip5 Models ◽

Ecological Processes ◽

The Past ◽

Spatiotemporal Characteristics ◽

Extreme Precipitation Events ◽

Precipitation Events

Extreme precipitation events, which have intensified with global warming over the past several decades, will become more intense in the future according to model projections. Although many studies have been performed, the occurrence patterns for extreme precipitation events in past and future periods in China remain unresolved. Additionally, few studies have explained how extreme precipitation events developed over the past 58 years and how they will evolve in the next 90 years as global warming becomes much more serious. In this paper, we evaluated the spatiotemporal characteristics of extreme precipitation events using indices for the frequency, quantity, intensity, and proportion of extreme precipitation, which were proposed by the World Meteorological Organization. We simultaneously analyzed the spatiotemporal characteristics of extreme precipitation in China from 2011 to 2100 using data obtained from the Coupled Model Intercomparison Project Phase 5 (CMIP5) models. Despite the fixed threshold, 95th percentile precipitation values were also used as the extreme precipitation threshold to reduce the influence of various rainfall events caused by different geographic locations; then, eight extreme precipitation indices (EPIs) were calculated to evaluate extreme precipitation in China. We found that the spatial characteristics of the eight EPIs exhibited downward trends from south to north. In the periods 1960–2017 and 2011–2100, trends in the EPIs were positive, but there were differences between different regions. In the past 58 years, the extreme precipitation increased in the northwest, southeast, and the Tibet Plateau of China, while decreased in northern China. Almost all the trends of EPIs are positive in the next two periods (2011–2055 and 2056–2100) except for some EPIs, such as intensity of extreme precipitation, which decrease in southeastern China in the second period (2056–2100). This study suggests that the frequency of extreme precipitation events in China will progressively increase, which implies that a substantial burden will be placed on social economies and terrestrial ecological processes.

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Dispersal, home-range size, and habitat use of an endangered land snail, the Oregon forestsnail (Allogona townsendiana)

Canadian Journal of Zoology ◽

10.1139/z2012-056 ◽

2012 ◽

Vol 90 (7) ◽

pp. 875-884 ◽

Cited By ~ 5

Author(s):

A.B. Edworthy ◽

K.M.M. Steensma ◽

H.M. Zandberg ◽

P.L. Lilley

Keyword(s):

British Columbia ◽

Home Range ◽

Habitat Use ◽

Land Snail ◽

Home Range Size ◽

Dispersal Distance ◽

Land Snails ◽

Dispersal Ability ◽

Suitable Habitat ◽

Maximum Displacement

Terrestrial molluscs have declined globally, often as a result of habitat loss and fragmentation. Many land snails are poor dispersers and exist in isolated habitat patches. The Oregon forestsnail ( Allogona townsendiana (I. Lea, 1838)) coincides with the most densely populated region of British Columbia and is listed as endangered in Canada. To investigate the dispersal distances and habitat-use patterns of Oregon forestsnails, we tagged and tracked 21 adult snails at Langley, British Columbia, for up to 3 years (2005–2008). The maximum daily dispersal distance for a snail was 4.5 m and the maximum displacement that we observed for a snail was 32.2 m during 3 years. Snails occupied home-range areas of 18.4–404.4 m2, often overlapping both forest and meadow habitat. Their home-range sizes were smaller in habitats with high availability of stinging nettle ( Urtica dioica L.), which may be an indicator of high-quality habitat. Our results suggest that the Oregon forestsnail is a relatively sedentary species with limited dispersal ability in its adult stage. Although Oregon forestsnails are likely unable to colonize suitable habitat independently, remnant forest–meadow mosaic patches such as our study site provide valuable habitat for Oregon forestsnail, which are supplementary to large tracts of intact forest where most of their populations are found.

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Breeding biology and post-fledging dispersal of red-crowned parakeets (Cyanoramphus novaezelandiae) translocated to a fenced mainland sanctuary

10.26686/wgtn.17060039.v1 ◽

2021 ◽

Author(s):

◽

Ellen Irwin

Keyword(s):

Reproductive Success ◽

Human Impacts ◽

Release Site ◽

Habitat Destruction ◽

Breeding Biology ◽

Food Sources ◽

Lifetime Reproductive Success ◽

Species Dispersal ◽

Dispersal Patterns ◽

Mammalian Predators

<p>With human impacts like habitat destruction and climate change contributing to range contractions in species, translocations stand out as an important tool for conserving species suffering from these effects. However, an understanding of the life history of many threatened species prior to translocation is often lacking, but critical for translocation success. For example, dispersal away from the release site—particularly when a protected release site is surrounded by unmanaged habitat—can result in translocation failure, and therefore successful translocation practice must include an understanding of a species’ dispersal patterns. I conducted a study examining the breeding biology and post-fledging dispersal of a population of red-crowned parakeets Cyanoramphus novaezelandiae), or kakariki, recently translocated to a mainland sanctuary in Wellington, New Zealand. The sanctuary, ZEALANDIA, is fenced to exclude invasive mammalian predators; however, birds can and do leave. Approximately one-third of juveniles that dispersed outside the sanctuary were killed by predators. Kakariki post-fledging dispersal was male-biased, possibly driven by inbreeding avoidance, and distance dispersed decreased with increasing body condition. Parental age may have also influenced offspring dispersal. In addition, I found that kakariki reproductive success may be affected by age, and estimated lifetime reproductive success was >30 fledglings by age five. Conservation initiatives could work on controlling predators in currently unprotected reserves and around food sources that kakariki targeted, particularly in summer and autumn when many plants are fruiting and recently fledged juveniles are more active. Future translocations should consider selecting younger birds to translocate to take advantage of their high lifetime reproductive success and therefore improve viability of populations.</p>

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The mismatch between location of protected areas and suitable habitat for the Vulnerable taruka Hippocamelus antisensis

Oryx ◽

10.1017/s0030605317001740 ◽

2018 ◽

Vol 53 (4) ◽

pp. 752-756 ◽

Cited By ~ 1

Author(s):

Cristina Mata ◽

Nicolás Fuentes-Allende ◽

Juan E. Malo ◽

André Vielma ◽

Benito A. González

Keyword(s):

Protected Areas ◽

Protected Area ◽

Species Distribution Model ◽

Human Impacts ◽

Atacama Desert ◽

Distribution Model ◽

Suitable Habitat ◽

Core Habitat ◽

Preferred Habitat ◽

Educational Programmes

AbstractProtected areas help to decrease human impacts on threatened mammals but do not always include species’ core habitats. Here we focus on the Vulnerable taruka Hippocamelus antisensis near the Atacama Desert, Chile, a population that is mainly threatened by interactions with local human communities. We develop a species distribution model for taruka and assess the contribution of protected areas to safeguarding its preferred habitat. From sightings (collected during 2004–2015), absence records (collected in 2014), and environmental variables, we determined that taruka habitat is scarce, highly fragmented and limited to humid areas. Only 7.7–11.2% of the taruka's core habitat is under protection. We recommend the establishment of a protected area in the south of Arica-Parinacota district, an area without settlements that lies within the taruka's core habitat, along with educational programmes, fencing of crops, and inclusion of communities in decision-making in areas where farmer–taruka interactions are negative.

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Anthropogenic and Climate Effects on a Free Dam Tropical River: Measuring the Contributions on Flow Regime

Sustainability ◽

10.3390/su122310030 ◽

2020 ◽

Vol 12 (23) ◽

pp. 10030

Author(s):

Verônica Léo ◽

Hersília Santos ◽

Letícia Pereira ◽

Lilia Oliveira

Keyword(s):

Climate Change ◽

Flow Regime ◽

River Flow ◽

Human Impacts ◽

Global Climate ◽

Rate Of Change ◽

Hydrologic Alteration ◽

Tropical River ◽

Range Of Variability Approach ◽

Flow Components

The demand for freshwater resources and climate change pose a simultaneous threat to rivers. Those impacts are often analyzed separately, and some human impacts are widely evaluated in river dynamics—especially in downstream areas rather than the consequences of land cover changes in headwater reaches. The distinction between anthropogenic and climate on the components of the flow regime is proposed here for an upstream free dam reach whose watershed is responsible for the water supply in Rio de Janeiro. Indicators of hydrologic alteration (IHA) and the range of variability approach (RVA) combined with statistical analyses of anthropogenic and climate parameters indicated that (1) four river flow components (magnitude, frequency, duration, and rate of change) were greatly altered from the previous period (1947 to 1967) and the actual (1994 to 2014); (2) shifts in the sea surface temperature of the Atlantic correlated with flow magnitude; (3) the cattle activity effects on the flow regime of the studied area decreased 42.6% of superficial discharge; global climate change led to a 10.8% reduction in the same river component. This research indicated that climate change will impact the intensification of human actions on rivers in the southeast Brazilian headwaters.

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