Endemic Ecosystems Research Articles

Anthropogenic threats in the border zone of the Amazon Forest: a case study of land use and land cover in RESEX Ciriaco, Maranhão, Brazil

The state of Maranhão is located in northeastern Brazil and covers three biomes, the Amazon Forest, Cerrado (savannah), and Caatinga (semi-arid), and an endemic ecosystem known as the Mata de Cocais (coconut forest). This study aimed to identify the land use and land cover (LU/LC) in RESEX Ciriaco, located in the border zone of the Amazon Forest of Maranhão, where occurs the Mata de Cocais. The database used in this study was obtained from the Brazilian Annual Land Use and Land Cover Mapping Project (Mapbiomas). The LU/LC in RESEX Ciriaco was carried out across 8,106.7 ha and a buffer zone with a 3 km radius was adopted. A map representing the class changes in the study area was created for the years 1985, 1992, 1999, 2006, 2013, 2020, and 2021. Despite the findings indicate a troubling particularly driven by the presence of pasturelands, the results demonstrate that RESEX Ciriaco has fulfilled its function of guaranteeing the sustainable use of natural resources without deforestation. However, the advancement of livestock and agriculture around RESEX Ciriaco poses a risk to the ecosystem. Creating a buffer zone for RESEX Ciriaco is vital for stopping the advancement of anthropogenic activities in the conservation unit.

Transition to a 100 % renewable power supply in galapagos islands: Long-term and short-term analysis for optimal operation and sizing of grid upgrades

Owing to their remarkable biodiversity and endemic ecosystems, the Galapagos Islands are one of the most important World Heritage sites. However, due to their isolation and remote geographical location, around 83.6 % of the energy supply in Galapagos relies on the use of fossil fuels, which are polluting the air, the land and the sea, therefore requiring an adequate energy planning for the efficient transition towards a more sustainable and environmentally friendly energy sources. Although there were several previous studies of the decarbonization of Galapagos’ energy supply, there is a need for a more comprehensive approach that will combine planning (long-term) and operational (short-term) analysis to evaluate both, the future investment plans and performance of evolving energy supply system, as well as to provide an in-depth evaluation of required system upgrades in terms of locally available renewable energy resources. In order to fill this gap, this paper presents results of two different studies for the optimal decarbonization and transition to a 100 % renewable energy supply of the Galapagos Islands, giving details on the development of modelling tools required for the analysis of different scenarios and various techno-economic constraints. The first study is used for a long-term for analysing and strategic planning of the energy matrix until 2050, starting from existing power plants and following projections for the deployment of new renewable-based energy generation and dedicated energy storage sources to determine the optimal sizing and timing of required grid upgrades. The second study is a short-term annual performance analysis, which considers days of minimum, average and maximum available renewable energy resources to optimize system operation with existing and additional renewable energy generation and storage sources that will minimize, or keep at a certain target level, contributions from diesel generation. The two presented studies complement each other, allowing to evaluate transition to a 100 % renewable energy supply in Galapagos from both the investment/planning perspective and from the operational point of view. The results of two studies are very close in terms of the sizes of required new PV generation and associated energy storage in Baltra-Santa Cruz islands by 2050 (around 50 MW of PV and 145 MW of storage), with the short-term study allowing to identify curtailed PV generation (on average around 140 MWh per day) as an opportunity to connect new controllable loads, and with the long-term study allowing to evaluate interim targets for decarbonization pathways to Net Zero by 2050 through the related techno-economic optimization.

Structure and diversity patterns of coralligenous cliffs across three ecoregions in the Central‐Western Mediterranean Sea

AbstractAimCoralligenous reefs are the main marine bioconstructions in terms of spatial distribution within the Mediterranean basin. Two distinct reef morphologies can be distinguished based on the surface and topographical features of the seafloor: cliffs developing vertical slopes and banks found on gently steep or horizontal bottoms. Despite their importance for monitoring and conservation efforts, observations regarding the variability of biogeographical patterns are scarce. Here, we aimed to assess the differences in the composition and structure of these cliffs across ecoregions and estimate the relative role of abiotic environmental features, geographic location, and connectivity in shaping diversity patterns.LocationThe study was carried out in the Central‐Western Mediterranean Sea. Samples were collected at 65 sites across the Algero‐Provençal Basin, the Ionian Sea and the Tyrrhenian Sea.MethodsWe assessed the composition and structure of coralligenous cliffs through photographic samplings collected by scuba divers. Patterns in α‐ and β‐diversity were associated with 9 abiotic environmental variables, latitudinal and longitudinal gradients, and connectivity measures using Generalized Additive (GAM) and Conditional Autoregressive (CAR) models.ResultsCoralligenous cliffs were primarily composed of algae and displayed a high degree of variability. The Partition Around Medoids (PAM) clustering method successfully delineated seven distinct clusters with a non‐uniform distribution within the studied ecoregions. The α‐diversity increased in eastern and northern sites and with phosphate concentration, while decreased with temperature, chlorophyll and nitrates concentration. β‐diversity at the site level increased with temperature, while it was negatively affected by northward current speed and chlorophyll concentration. Moveover, β‐diversity increased within connected sites.Main ConclusionsCoralligenous cliff diversity responds both to the physico‐chemical features of the habitat and between‐habitats connectivity. However, our findings suggest that small‐scale abiotic and biotic processes could contribute to explaining the variability observed. These findings can significantly enhance the monitoring and conservation efforts of this Mediterranean endemic ecosystem.

Genofond drvenastih vrsta na području strogog rezervata prirode "Felješana"

Forests of primeval character in Europe usually receive the highest protection status. The importance of these ecosystems is highlighted in the BIO2023 Strategy, which outlines specific guidelines for the identification and protection of primeval forests within the European Union. Endemic ecosystems characteristic of Europe, such as pure beech forests, are facing numerous threatening factors in the context of climate change and are considered one of the most endangered habitats. Efforts to preserve and enhance forest ecosystems, as an initial step, involve conservation and long-term monitoring to gain insight into the adaptation and evolutionary strategies of the present species and ecosystems as a whole. The extremely strict protection conditions prescribed in strict reserves impose very limited human intervention, while non-invasive scientific research is considered a desirable activity. One of the first protected pure beech forests in Serbia is the Strict Nature Reserve "Felješana" which, despite being protected since 1950, has not been thoroughly and systematically studied from the aspect of woody species diversity. The aim of this paper is to provide, for the first time,data on the available gene pool of woody species in the primeval beech forest "Felješana". The field research methodology included recording woody species in the tree, shrub, and ground layers at predetermined monitoring points and identifying and georeferencing target species. For the georeferenced individuals of the target species, height, diameter at breast height, breast circumference, and horizontal crown projection were determined. A total of 27 native woody species were recorded, with 14 species in the tree layer, 25 in the shrub layer, and 19 in the ground layer. Although beech is the dominant species across all three vegetation layers throughout the area, the recorded number of species in the shrub and ground layers indicates the potential for changes in species distribution and composition in this reserve in the future. All recorded species are of native origin, among which six species belong to one of the categories of rare, endangered, and vulnerable species in the forest fund of Serbia. Georeferencing and determining the basic characteristics of the target species individuals have provided a solid foundation for long-term monitoring of the gene pool and the conservation of woody species in SNR "Felješana".

Estimating the Impact of Climate and Vegetation Changes on Runoff Risk across the Hawaiian Landscape

In Hawai’i, ecosystem conservation practitioners are increasingly considering the potential ecohydrological benefits from applied conservation action to mitigate the degrading impacts of runoff on native and restored ecosystems. One determinant of runoff is excess rainfall events where rainfall rates exceed the infiltration capacity of soils. To help understand runoff risks, we calculated the probability of excess rainfall events across the Hawaiian landscape by comparing the probability distributions of projected rainfall frequency and land-cover-specific infiltration capacity. We characterized soil infiltration capacity based on different land cover types (bare soil, grasses, and woody vegetation) and compared them to the frequency of large rainfall events under current and future climate scenarios. We then mapped the potential risk of excess rainfall across the main Hawaiian Islands. Our results show that land cover type has a very large effect on runoff risk as excess rainfall conditions are 234% more likely in bare soil and 75% more likely in grasslands compared to woody forests and shrublands. In contrast, projected shifts in rainfall intensity by end-of-century show little impact on these probabilities and thus, the risk of runoff. This indicates that the probability of excess rainfall is primarily driven by differences in land cover and not by current or potential shifts in rainfall patterns across the Hawaiian landscape. The ability to estimate the risk of potentially ecologically and economically costly runoff based on changes of land cover is useful for managers focused on invasive species control and restoration planning, especially for native and endemic ecosystems unique to the State of Hawai’i.

A Study of Traditionally Managed Khazan Ecosystems of Ponda Taluka, Goa

Khazan lands are reclaimed mangrove areas found in the state of Goa where eco -friendly farming, aquaculture features were practiced by villagers more than work thousands of years. Present study related to khazan ecosystems was carried out by selecting five villages that aims to document the ethnobotanical knowledge involved structure; management strategies; ecological and economical activities; livelihood support received by local people; community participation in protecting khazan ecosystems. Surveys and interviews were carried in five villages from Ponda taluka , from the state Goa . Data were collected through open semi structured interviews with the informants. It was recorded that the structure of khazan ecosystem comprise of estuaries, backwaters, mangrove areas, outer and inner embankments, sluice gates and poiem (depression). This Primitive khazan technology comprises of sluice gates made from wood of Terminalia tomentosa, canoes used in fishing are crafted from wood of Mangifera indica. Villagers managed khazans by forming associations called Bous , by growing traditional salt tolerant rice varieties like korgut , by protecting mangroves, following rituals like offering choru and bali , Mange Thapni (unique way crocodile conservation) for protecting khazans. In all 15 different types of crop plants, 11 true mangroves and 6 mangrove associates were recovered from study sites. Khazan lands have been traditionally source of livelihood for locals. They grow salt tolerant rice varieties, carry out aquaculture activities by equitably sharing the resources. This age old technology needs to be preserved as environmental degradation, change in land-use patterns, tourism, and overexploitation have left many khazans marshy and fallow. This study represents a useful inventory of how these endemic ecosystems were managed and to spread this knowledge.

DIFFERENTIATION IN PHENOTYPIC PLASTICITY TO CLIMATE AMONG ERIOGONUM FASCICULATUM SUBSP. FOLIOLOSUM (POLYGONACEAE) POPULATIONS IN CALIFORNIA

California, a hotspot of plant biodiversity, is projected to experience a significant increase in average temperature by the end of the century, from +1.5°C under low emissions to +4°C under medium-high emissions models. This warming could severely affect unique, endemic ecosystems like the chaparral. Phenotypic plasticity, the capacity of organisms to express different phenotypes in response to environmental cues, may be an important means by which plants adjust to climate change. Here, we examine differentiation in two traits related to climate adaptation, leaf length and trichome density, previously observed to differ qualitatively between coastal and inland populations of Eriogonum fasciculatum subsp. foliolosum (Nutt.) S.Stokes. We quantitatively verify these leaf trait differences, assess whether they are plastic to temperature, and also assess whether coastal and inland populations express this plasticity differently. We performed field collections, established a novel procedure for vegetative propagation of woody cuttings, and grew cuttings and germinated seeds in temperature treatments simulating current conditions and those projected by future climate models. Our results revealed that leaf traits of both populations respond plastically to temperature, and we also found differentiation for the plasticity expressed by the two populations. Population genetic analyses detected limited genetic differentiation and high gene flow between these two populations, indicating that the observed differentiation in plasticity may be locally adaptive. Together, these findings suggest that this system may exemplify genetic accommodation, in which the evolution of plasticity mediates adaptation, and imply that variation in plasticity is relevant to conservation strategies for this plant and other California native chaparral shrubs in the face of climate change.

Desarrollo de herramientas tecnológicas didácticas para la implementación de un programa de educación ambiental no formal

In Mexico, environmental problems require the intervention of all sectors of society, higher education institutions are an important axis to develop a sustainable society aware of environmental care. The educational community is undoubtedly one of the key sectors in contributing to the improvement of environmental quality, both because of its responsibility in educating citizens and because of the influence it has on the rest of society. Technological tools are new forms of communication and information in both public and private spheres, and must be integrated into educational systems as a didactic resource choice, which is why this document presents a project to use technological tools as part of a non-formal environmental education program, which will serve as a means of learning for environmental awareness and education that allow the regional conservation of the thorny ecosystem, mainly of the reserve that is located in the Mario Molina Technological University Lagos de Moreno Academic Unit. For the selection of the material that the program will contain, 68 children between 6 and 15 years old were surveyed, of which 84% do not know that it is a nature reserve and 90% are unaware of the ecological reserves of Lagos de Moreno; That is why as part of this non-formal environmental education program, one of the tools generated was the design and development of a web page that serves as an environmental education center for the ecological reserve, where it is intended that the Laguense population know the only endemic ecosystem of this municipal head. Another tool that was carried out was the development of didactic software represented by games aimed at obtaining knowledge of the flora and fauna that exist in the thorny forest of the ecological reserve of the Technological Mario Molina Lagos de Moreno Academic Unit, as well as the diversity of other thorn forests in other regions and with this tool strengthen the learning and awareness process about thorn ecosystems.

A NEW SPECIES OF THE AMPHIPOD <i>MELITA</i> LEACH, 1814 (CRUSTACEA: AMPHIPODA: MELITIDAE) FOR THE AZOV-BLACK SEA BASIN

Amphipods of the genus (Melitidae, Amphipoda) were found in the Kerch Strait (Black Sea) in September 2019 and March, July, November 2020. The material was collected in the formations formed by the polychaete (Fauvel, 1923). The depth ranged from 0.1 to 0.2 m. The individuals found in this site do not belong to the species (Montagu, 1804) known in the Black Sea, but they correspond to the morphological characters of the genus Melita . The species discovered is as close as possible to the species Melita setiflagella Yamato, 1988, whose natural range is located in the estuaries of rivers in Japan. Invasive range covers coastal waters of the Atlantic coast of Europe, the Pacific and Atlantic coasts of the United States and the Atlantic coast of Argentina. Presumably, this invader was accidentally introduced into the Black Sea with ballast waters or by transfer with fouling of ship surfaces. M. cf . setiflagella formed a stable self-reproducing population in the Kerch Strait. Therefore, it is important to monitor the distribution of this amphipod in order to predict the consequences for endemic species and local ecosystems.

Saline Soils: A Potentially Significant Geoheritage of the Vojvodina Region, Northern Serbia

Halomorphic (or saline) soils, are characterized by high concentrations of soluble salts or sodium, or both. Saline soils have unfavorable agricultural properties but provide the natural habitats for a variety of highly specialized plants, animals, and other organisms. It is these special interactions that create the typical landscape of saline soils, known as “slatina”. The aim of this study is to assess and evaluate the geotouristic potential of six of the most attractive slatina sites in the Vojvodina region, Northern Serbia: Jegrička, Slano Kopovo, Rusanda, Okanj, Pečena slatina, and Pašnjaci Velike Droplje. Overall, all analyzed sites have significant tourism potential, based on both natural and tourist values. In addition to the tourism potentials, analyzed sites have high value as a natural endemic ecosystem inhabited with highly specialized plants and birds.

Impacts by feral goats on critically endangered Crepidiastrum grandicollum (Compositae) endemic to the Ogasawara Islands

AbstractOceanic islands are biodiversity hotspots with highly endemic ecosystems that are vulnerable to invasive alien species. Understanding the status of endangered species and identifying threats have the highest priority for insular biodiversity conservation. The two remaining populations of endangered Crepidiastrum grandicollum on Chichi‐jima Island were studied for 5 years to describe their status and evaluate the impacts of feral goats (Capra hircus). The main cause of population decline was browsing by goats. The populations protected by the exclosures were stable but declined after an exclosure was removed. Even in the protected population, regeneration was limited outside the exclosures and in 1 year of the survey, a high proportion of feeding damage by moth larvae was observed in one population. These facts indicate that exclosures are not a sufficient conservation measure, and eradication of goats and population restoration in novel habitats are necessary to reduce the extinction risk of C. grandicollum.

Changing nutrient cycling in Lake Baikal, the world’s oldest lake

Lake Baikal, lying in a rift zone in southeastern Siberia, is the world's oldest, deepest, and most voluminous lake that began to form over 30 million years ago. Cited as the "most outstanding example of a freshwater ecosystem" and designated a World Heritage Site in 1996 due to its high level of endemicity, the lake and its ecosystem have become increasingly threatened by both climate change and anthropogenic disturbance. Here, we present a record of nutrient cycling in the lake, derived from the silicon isotope composition of diatoms, which dominate aquatic primary productivity. Using historical records from the region, we assess the extent to which natural and anthropogenic factors have altered biogeochemical cycling in the lake over the last 2,000 y. We show that rates of nutrient supply from deep waters to the photic zone have dramatically increased since the mid-19th century in response to changing wind dynamics, reduced ice cover, and their associated impact on limnological processes in the lake. With stressors linked to untreated sewage and catchment development also now impacting the near-shore region of Lake Baikal, the resilience of the lake's highly endemic ecosystem to ongoing and future disturbance is increasingly uncertain.

Evolutionary status of the invasive muskrat Ondatra zibethicus revealed by complete mitochondrial genome

The muskrat Ondatra zibethicus is native to North America, However it has successfully dispersed into most areas of northeast China in the past decades, which may lead to potential impact on endemic eco-system. We determined and annotated the whole mtDNA genome of the muskrat O. zibethicus to better understand the evolutionary relationship of this invasive species with other Rodentia distributed in China. The complete mitogenome is 16,351 bp in length, includes 13 protein-coding genes, 22 tRNA genes, 2 rRNA genes, and a control region. We built the phylogenetic tree of muskrat and other 11 most closely related Rodentia species.

The road to deforestation: Edge effects in an endemic ecosystem in Sumatra, Indonesia

Worldwide, roads are a main driver of deforestation and degradation as they increase forest access along the forest edge. In many tropical areas, unofficial roads go unreported and unrecorded, resulting in inaccurate estimates of intact forested areas. This is the case in central Sumatra, which boasts populations of critically endangered Sumatran elephants (Elephas maximus sumatrensis), tigers (Panthera tigris sumatrae) and other endemic flora and fauna that make the area globally unique. However, maps do not reflect the reality of forest loss in the area. Here we present new maps from 2002 and 2016 of digitized and ground-truthed roads in one of Sumatra’s unique lowland tropical protected areas, Tesso Nilo National Park. Using our newly created roads dataset, we examine the distribution of forest with respect to distance to roads. Our data show >2,400 km of roads within the national park in 2016 –nearly a 10-fold increase from roads known in 2002. Most forest (82–99%) within Tesso Nilo falls within 100 m, 500 m, and 1000 m of road edges. Length of road increased 157% and road density increased from 1.06 km/km2 to 2.63 km/km2 from 2002–2016. Our results suggest that this endemic ecosystem is facing substantial threat from roads and their associated impacts. Without swift management action, such as road closures and increased enforcements by park management, this ecosystem, and its endemic wildlife, could be lost. It is imperative that protected areas worldwide more rigorously consider roads and road effects on ecosystem fragmentation in their conservation plans.

Air quality and the visitor experience in parks and protected areas

Air pollution is one of the greatest environmental health risks facing people worldwide. The transboundary nature of air pollution may place park and protected area (PPA) resources, as well as visitors, at risk of exposure to the same harmful pollutants that plague urban populations. Despite our knowledge of the various impacts of air pollution on endemic species, ecosystem functions, and human health, there exists a gap in our understanding of the affective, behavioral, and cognitive role of air pollution in the visitor experience in PPAs. We reduced this deficit by conducting a scoping review of existing empirical social science literature focused on the social and psychological effects of degraded air quality in and around PPAs. Using a systematic scoping process, we assessed peer-reviewed, empirical social science articles (n = 458), for evidence of human dimensions of air quality scholarship in International Union for Conservation of Nature (IUCN) protected area sites. Results suggest a relative dearth of peer-reviewed social science scholarship explicitly focused on the visitor experience of air quality in PPAs worldwide. Descriptive analyses illustrate a consolidation of scholarship in specific publications, as well as geographic concentration of scholarship in North American protected areas and IUCN Category II (National Parks). Subsequent inductive analyses yielded five emergent themes—ecosystem services, visitor impacts, transit, measurement of behavior, and variable importance—evident in human dimensions of air quality literature, as well as variety of implications for future human dimensions of air quality scholarship and PPA management.

Climate variability and forest fires in central and south‐central Chile

AbstractThis paper evaluates the relationship between fire occurrence (number and burned area) and climate variability (precipitation and maximum temperatures) across central and south‐central Chile (32°–43° S) during recent decades (1976–2013). This region sustains the largest proportion of the Chilean population, contains ecologically important remnants of endemic ecosystems, the largest extension of forest exotic plantations, and concentrates most of the fire activity in the country. Fire activity in central Chile was mainly associated with above‐average precipitation during winter of the previous year and with dry conditions during spring to summer. The later association was particularly strong in the southern, wetter part of the study region. Maximum temperature had a positive significant relationship with burned area across the study region, with stronger correlations toward the south. Fires in central Chile were significantly related to El Niño–Southern Oscillation, through rainfall anomalies during the year previous to the fire season. The Antarctic Oscillation during winter through summer was positively related to fires across the study area due to drier/warmer conditions associated with the positive polarity of this oscillation. Climate change projections for the region reveal an all‐season decrease in precipitation and increases in temperature, that may likely result in an increment of the occurrence and the area affected by fires, as it has been observed during a multi‐year drought afflicting central Chile since 2010.

Visual Discrimination and Large Area Mapping of Posidonia Oceanica Using a Lightweight AUV

Controlling and quantifying the presence of Posidonia Oceanica (P.O.) in the Mediterranean sea is crucial for the conservation of these endemic ecosystems and to underscore the negative impact of many anthropogenic activities. These activities, which include uncontrolled leisure anchoring or illegal drag fishing, directly affect the tourism and fishing industries. Nowadays, the control and quantification of P.O. is done by divers, in a slow and imprecise process achieved in successive missions of a duration limited by the capacity of the oxygen scuba tanks. This paper proposes the application of robotic and computer vision technologies to upgrade the current P.O. control methods, building large scale coverage maps using the imagery provided by an autonomous underwater vehicle endowed with a bottom-looking camera. The process includes four main steps: 1) training a classifier based on two different Gabor filter image patch descriptors and a support vector machine ; 2) detecting P.O. autonomously, both on-line and off-line , in each individual image; 3) color photo-mosaicking the area explored by the vehicle to obtain a global view of the meadow structure; these mosaics are extremely useful to analyze the structure and extension of the meadow and to calculate some of the biological descriptors needed to diagnose its state; and 4) building a binary coverage map in which the classification results of areas with image overlap are fused according to four different strategies. The experiments, performed in coastal areas of Mallorca and Girona, evaluate and compare the proposed descriptors and fusion techniques, showing, in some cases, accuracies and precisions above 90% in the detection of different patterns of P.O., from video sequences at different locations, in different seasons and with different environmental conditions.

New distribution records of Pteronura brasiliensis (Zimmerman, 1780) (Mammalia, Carnivora) in Roraima, northern Brazilian Amazonia

A survey of the Giant Otter, Pteronura brasiliensis (Zimmerman, 1780), in the state of Roraima, northern Brazilian Amazonia, is presented. We include 52 new records, increasing the total geographic coordinate points for the species in this area by 360%. Additionally, this study reports the first occurrence of the P. brasiliensis in the lavrado region, a unique and endemic ecosystem of South America with high biodiversity, which claims for protection and adequate land use planning.

Response of a coastal hydrogeological system to a rapid decline in sea level; the case of Zuqim springs – The largest discharge area along the Dead Sea coast

Summary The almost instantaneous response of a natural on-shore groundwater system to an extremely rapid drop in the level of an adjacent lake is described in this study. The study is focused on the Zuqim (Feshcha) spring complex located on the northwestern shore of the Dead Sea, which exhibits a drop of tens of meters in its water level over the last few decades. In this exceptional “field lab”, fluctuations and trends in the flow regime are recognized, as well as the contemporaneous geochemical variations. Lithological facies variations have a pronounced effect on the underground flow regime. The following main processes were recognized: (a) slight shifting of the long-standing springs eastward, following the retreating shore; (b) extension of the hydrologic system southward without significant change in the total discharge of the entire spring complex. The new seepages are characterized by high variability in salinity; and (c) continuous refreshing of the spring water as a result of prolonged flushing of old trapped brines. The water of the Zuqim springs lie on mixing lines between two local brine types and diluted brine of the Lisan Lake – the precursor of the Dead Sea. Based on our findings, future development processes in the spring complex are predicted, which is essential because of their impact on the endemic ecosystem that relies on this water. In addition, continuation of the rapid drop in lake level is expected to cause intensification of erosional processes, such as deepening of flow gullies. Shifting of the entire hydrological system southward and migration along with the retreating shore is also expected to continue, as well as the continuous decrease in the water salinity.

Changes in invertebrate assemblage structure as affected by the flow regulation of a páramo river

Flow regulation can alter the structure and dynamics of lotic communities, especially in rivers with unpredictable high-flow events, such as those flowing through the Paramo, an endemic ecosystem of the high-altitude Neotropical Andes. This study evaluated how flow regulation affects invertebrate assemblage structure in a Paramo river. In both the wet and dry seasons, the study assessed flow history, water chemistry and mesohabitat characteristics in their relation to assemblage structures upstream (undisturbed reach) and downstream (disturbed reach) of a water diversion structure. The elimination of spates through flow regulation did not lead to a complete change in the assemblage components at the disturbed reach. Instead, it led to an assemblage structure with a greater genera-richness, a lower genera-evenness and a greater occurrence of certain genera, e.g., Pristina , Alotanypus , Polypedilum and Austrolimnius . These genera lacked resistance-resilience adaptations, which would allow them to survive in mesohabitat conditions resulting from increased hydromorphological stability, namely higher fine sediment retention, higher benthic organic matter (BOM) and lower hydraulic stress. Overall, the results of this study reinforce the assertion that, in Paramo rivers, the temporal dynamics of the natural flow regime significantly control the structure of invertebrate assemblages. Thus, to preserve these rivers' biotic assemblages, it will be necessary to implement new regulation plans that mimic their natural flow histories.