Habitat For Fauna Research Articles

Tracking earthworm fluxes at the interface between tree rows and crop habitats in a Mediterranean alley cropping field

Alley cropping is the combination of tree rows and crop alleys. The tree row is covered by an understory vegetation strip (UVS), providing a beneficial habitat for many soil fauna, which could disperse through spillover to the crop alleys. However, such movements have never been directly studied. Our experiment investigated earthworm fluxes in the tree row vicinity using a trap technique, in a Mediterranean agroforestry alley cropping field cultivated with peas and planted with walnut trees. We assessed earthworm density at different distances from the UVS (0 m, 0.3 m, 1 m and 6 m) by hand sorting soil monoliths (25*25*30 cm) in spring 2019, at the start and the end of a two-month experiment. During this period, we detected earthworm fluxes by placing directional traps at 30 cm from the UVS border. Traps consisted of three glued plastic walls placed vertically in the soil. They delimited a soil block of 25*25 cm by 20 cm depth and were open on one side. More epigeic earthworms were found in the UVS and up to 30 cm from the UVS border than in the middle of the crop alley. By contrast, the earthworm Allolobophora chlorotica presented a homogeneous distribution in the plot. Trapped earthworms were mostly of the All. chlorotica species, and 1.6 times more earthworms were found in traps open towards the crop alley than in traps open towards the UVS. These results suggest that in spring, earthworms are moving more from the crop alley towards the UVS than in the other direction, probably using the tree row and its vicinity as a refuge against adverse summer conditions in the crop alley.

Assessment and Characterization of Woji Creek Riverbed in Port Harcourt, Rivers State, Nigeria, Utilizing Side Scan Sonar Technology

Woji Creek plays a crucial role in vessel navigation, supports diverse flora and fauna habitats, and sustains local livelihoods. However, human activities and natural events have led to changes in its riverbed over time. Given its significance for coastal stability and geomorphology, there is a pressing need to classify, evaluate, and ensure its environmental sustainability. The primary objective of this study is to employ side scan sonar technology to classify and assess the riverbed of Woji Creek in Port Harcourt, Nigeria. The study aims to classify the riverbed, analyze water depth variations, evaluate navigational suitability, and determine turbidity levels within the creek. To achieve these objectives, the methodology involved acquiring Side-Scan Sonar (SSS) and Sub-bottom profile data. These datasets underwent backscatter processing to create geocoded backscatter images. Feature points were extracted and matched from these images to derive riverbed classification, depth categories, water volume distribution, and river turbidity analysis. The riverbed classification revealed the presence of three primary sediment types: Clayey Silty Sand, Silty Clay, and Silty Sand, each with distinct implications for navigation. Shallow, Moderate, Deep, and Very Deep areas were identified within Woji Creek, each influencing navigational conditions. Additionally, the water volume distribution analysis provided essential insights into depth limitations and route planning.
 Moreover, the assessment of river turbidity identified low, moderate, and high turbidity zones, reflecting water clarity and suspended particle levels. These findings serve as invaluable decision support tools for navigation planning and management in Woji Creek, offering comprehensive insights into the riverbed, depth suitability, volume distribution, and water quality. Leveraging this data can enhance strategic decision-making processes and contribute to the sustainable management of this vital waterway.

Natural and anthropogenic impacts on mangrove carbon dynamics: a systematic review protocol

The mangrove ecosystem serves as a vital habitat for coastal flora and fauna while playing a crucial role in storing and sequestering carbon as part of global carbon cycles. Therefore, it is imperative to evaluate the carbon dynamics, encompassing storage and sequestration, within mangrove ecosystems and their interconnectedness with natural climate fluctuations and anthropogenic influences, including land-use and land-cover changes (LULCC). Although there has been an increase in monitoring data and literature on mangrove carbon dynamics over the past two decades, there is still limited understanding regarding how climate variability, when combined with anthropogenic drivers, moderates the resilience of carbon storage and sequestration in mangroves. This study aims to build upon and enhance the previous systematic review conducted by Sasmito et al. (2019). Our specific objectives involve collating more recent literature published since 2018 and strengthening the analysis of carbon loss and recovery in tree biomass across different species, as well as its correlation with local and regional climate variations. Additionally, we will explore the impact of various types of land-use and land-cover changes on mangrove forests. Our systematic review will focus on field-based data collected from the Asia Pacific mangrove region, which represents the world’s largest and most diverse mangrove ecosystem and has been extensively studied in comparison to other regions, as indicated by previous systematic reviews. To gather relevant literature, we will conduct comprehensive searches across various databases, including Scopus, Web of Science, and Google Scholar. The structure established by Sasmito et al. (2019) for literature search, screening, and data extraction will be adopted. Data analysis will involve comparing carbon storage and sequestration under locally and regionally varying climatic conditions and anthropogenic influences. Furthermore, we will employ geographical mapping techniques to visualize species distribution and diversity within the Asia Pacific region, while also estimating carbon storage and recovery capacities.

Isotopic insights into the Early Acheulean (1.95 Ma–1.66 Ma) high-elevation paleoenvironments at Melka Kunture (Upper Awash Valley, Ethiopia)

In this paper, we present stable carbon and oxygen isotope analyses of fauna tooth enamel from Garba IVD (1.95 Ma) and Gombore IB (1.66 Ma), two Early Acheulean sites of Melka Kunture (Upper Awash, Ethiopia), and discuss faunal taxonomy and fossil pollen. Our aim is to infer the diet and habitat of the fossil fauna, as well as the environment of both sites, in order to provide a broader paleoecological reconstruction. During the Pleistocene, the vegetation of the highlands of Ethiopia belonged to the Dry evergreen Afromontane Forest and grassland complex, which is distinct from the savanna of lower elevations in eastern Africa. Our carbon isotopic results indicate that all the analyzed faunal taxa were grazers consuming C4 plants, whereas oxygen isotopic results discriminate the taxa according to their semiaquatic or terrestrial habitats. These results are consistent with the taxonomic composition of the faunal assemblages and the palynological results, suggesting extended mountain grasslands in the landscape at Garba IVD. In contrast, the carbon isotopic results do not totally agree with the pollen paleoenvironmental reconstruction at Gombore IB, where the open vegetation was interrupted by forests and bushy vegetation. Stable isotope and pollen data provide different outcomes (feeding strategies vs. nearby plants) and have different temporal and spatial resolutions. This is relevant when reconstructing past environments by using independent proxies. Furthermore, isotopic comparisons with other Early Pleistocene paleontological and archaeological sites from eastern Africa indicate that all the analyzed taxa in common fed on C4 plants and that their dietary strategies were not affected by variations linked to the difference in elevations.

Inventory of Large Mammals in Ujung Kulon National Park, Banten Province

The National Park has a diverse ecosystem for the preservation of flora and fauna, making Ujung Kulon National Park a habitat for endemic and protected fauna. Large mammals are one of the many animals found in TNUK, especially those with protected status. This study aims to determine the diversity of large mammal species in Ujung Kulon National Park. The research was conducted on September 27–29, 2022, in Ujung Kulon National Park, which is located at the western tip of Java Island, precisely in Sumur and Cimanggu Districts, Pandeglang Regency, Banten Province. The method used was the cruising method using exploratory descriptive data analysis. The results showed that there were two types of large mammals, namely ungulate mammals and primate mammals. The number obtained was 10 types of mammal species belonging to 7 different families. Large mammals found include Rhinoceros sondaicus, Muntiacus muntjak, Cervus timorensis, Hyolobates moloch, Presbytis comata, Trachypitecus auratus, Macaca fascicularis, Sus scrofa, Tragulus javanicus, and Bubalus bubalis. Most of the large mammals found are endemic mammals with protected status. Of the large mammals found, the most common were hoofed mammals. With this study, the public has an awareness of the importance of maintaining the diversity of fauna and flora in Ujung Kulon National Park

Microbial communities and mineral assemblages in sediments from various habitats at the Haima Cold Seep, South China Sea

Cold seeps create diverse habitats in the deep sea and play an important role in the global carbon cycling. Anaerobic oxidation of methane (AOM) and biogenic mineralization are essential carbon pathways of methane and carbon transformation in cold seeps, however, the effects of habitat heterogeneity on the processes are still poorly understood. In this study, we investigated the microbial communities and mineral assemblages at distinct habitats in the Haima cold seep and their relationships with environmental factors. These habitats were classified as methane seep site (MS), seep-free faunal habitat (FH), and control site (CS). Bacterial communities were significantly different among the three habitats. ANME-3 archaea, Sulfurovum bacteria, and mineralization-associated microbes (e.g., Campylobacterales) were detected in high relative abundances at ROV2. Mineralogical analysis revealed abundant calcite minerals at the seep site, indicating that authigenic carbonate minerals were formed at highly active seep. Multivariate statistical analysis demonstrated that the concentrations of SO42–, Ca2+, and Mg2+ were significantly correlated with the presence of calcite minerals and bacterial communities. These results suggested that AOM-accompanied authigenic carbonate formation is an important factor influencing the mineral assemblages in seep habitats. This finding improves our understanding of marine microbial carbon cycling.

Camptostemon philippinensis, a new record of endangered mangrove species in the Balikpapan Bay, East Kalimantan, Indonesia

Background Camptostemon philippinensis, found in mangrove forests in Indonesia and the Philippines, is listed as endangered on the International Union for Conservation of Nature (IUCN) Red List. It is found primarily in isolated mangrove forests in Kalimantan (Indonesian Borneo) and Sulawesi in Indonesia. Despite significant studies on mangrove biodiversity in this region, the occurrence of C. philippinensis in Balikpapan Bay, East Kalimantan, is not extensively recorded. Methods The study was conducted by exploring the mangrove forests along Balikpapan Bay. The first survey of about 200 km was conducted to observe mangrove vegetation and found one C. philippinensis tree. The second survey focused on the area around the first discovered C. philippinensis tree to census and record its growth stage and distribution. Results The study recorded a population of 527 individuals of C. philippinensis in Pantai Lango Village, East Kalimantan, dominated by seedlings. The high number of seedlings indicates good natural regeneration potential, but the low number of trees indicates intense competition for space in a restricted habitat. This species inhabits a small and restricted area in Balikpapan Bay, in the middle area of Balikpapan Bay, and is associated with other mangrove flora, such as Rhizophora apiculata, Rhizophora mucronata, Sonneratia alba, Avicennia alba, Lumnitzera littorea, Osbornia octodonta, Ceriops tagal, and Xylocarpus granatum. Conclusions C. philippinensis is vulnerable to habitat damage from anthropogenic activities, which could lead to local extinction. Its natural habitat in Balikpapan Bay also has the potential to be under pressure due to the development of Indonesia’s new capital city (Ibu Kota Nusantara/IKN). It emphasizes the need to understand the ecological role of this protected flora in the natural habitat of protected fauna (the proboscis monkey). Documenting the population of C. philippinensis is crucial for conservation efforts, including propagation and understanding its ecological role.

Improvements in the design of nest cavities to attract cephalopods and crustaceans in a green artificial reef unit according to tridimensional hydrodynamic criteria – Application to the Ares-Betanzos estuary

Installing artificial reefs (ARs) on the seabed creates a hard substrate that alters water flow and causes different species to settle. For this reason, by applying hydrodynamics to ARs, a useful tool is created for analysing these reefs so that there is adequate nutrient circulation and a propitious habitat for benthic and pelagic fauna. Using hydrodynamic criteria to characterise the velocity field, the present work aims to propose a methodology for positioning nest cavities within an AR unit in which different species will settle. Biological considerations, such as nutrient supply as well as the most suitable size and shape for the nest cavities, are taken into account. A state-of-the-art 3D shallow water model is validated and applied to the Ares-Betanzos estuary (NW Spain), where the installation of an AR group has recently been proposed. This coastal body, with a complex 3D hydrodynamic structure, was achieved under representative average conditions in absence of winds, which in turn greatly differs both in space and time throughout a spring-neap tidal cycle. A 3D CFD (Computational Fluid Dynamics) tool is applied to model food delivery on the AR. Moreover, the optimal geometry and position of nest cavities are established through a created indicator, ARnest cavity position, in order to provide sufficient nutrient circulation. It was found that the most appropriate shape for the nest cavities is cylindrical and a diameter of 200–300 mm is the most appropriate size. In terms of the ideal positions for the nest cavities, these depend on the orientation of the AR with respect to the current velocity. One of the orientations analysed leads to sufficient nutrient supply to the whole AR, while the other orientation analysed leads to sufficient nutrient supply to the high and mid positions at the front face, mid and low positions at the back face and all positions along the lateral faces.

Assessment of Diversity of Marine Organisms among Natural and Transplanted Seagrass Meadows

Seagrass ecosystems have been declining, and restorations are conducted in many parts of the world to compensate for habitat loss and restore the ecosystem services seagrasses provide. Assessment of transplantation success requires the monitoring of the level of biodiversity between the donor and transplanted sites. In this study, we assessed a seagrass ecosystem after restoration in terms of the diversity of marine organisms using environmental DNA (eDNA) to compare four sites: (1) bare sand, (2) a natural meadow of Cymodocea serrulata, (3) a natural meadow of Halophila ovalis, and (4) a transplanted seagrass meadow. The results showed the presence of 3 domains, 34 phyla, 59 classes, 92 orders, 155 families, 156 genera, and 121 species. Proteobacteria, Actinobacteria, Cyanobacteria, and Bacteroidetes were the dominant bacterial phyla. Among eukaryotes, Phragmoplastophyta/Charophyta (epiphytes), Ascomycota (fungi), Cnidaria (jelly fish), and Arthropoda (Crabs and bivalves) were the dominant phyla. Dugong tails and commercial species (sea cucumber, dog conch, and swimming crab) have been observed in both the natural and transplanted meadows. Relative abundance among the four sites was significantly different. There were no differences in species richness and evenness between the four sites and no differences in species richness and evenness between the natural meadows and the transplanted seagrass meadow. It is possible that transplanted seagrass meadow can be successfully restored and established and can provide habitat for fauna and microbes. Additionally, fauna are not limited in their capacity to move between the natural and transplanted habitats. This study provides an assessment of biodiversity of restored seagrass patches and a better understanding of a seagrass ecosystem after restoration. However, to assess seagrass ecosystem services after restoration and the success of restoration actions, long-term monitoring of marine organism diversity and additional assessments are needed.

First Physico-Chemical and Traditional Characterisation of Lake Tseny, Northwest Madagascar

This study was designed to assess the biophysical structure, traditional practices and water quality of Lake Tseny in northwest Madagascar. The lake was divided into five zones: the central zone and the littoral zones (east, north, west and south). Transects and direct observation were used to estimate submerged tree and vegetation cover. Information on local traditions was collected through interviews with key people and visits to sacred sites. Water quality was assessed during the rainy and dry seasons, 2017–2018. Samples were taken twice a day, in the early morning and evening, at randomly selected points at intervals of 400m. The aquatic vegetation covered over 75% of the lakeshore. Most of the submerged tree trunks were recorded along the western area. Five sacred sites associated with eight forms of traditional taboos to reduce the potential source of water pollution were recorded in and around the lake. The lake is bowl shaped. The water was warm (T° 25.3 - 35.6 °C), slightly alkaline (pH 7.1 - 8.5), well oxygenated (DO 4.63 - 9.6 mg/l ) and less mineralised (EC 71.70 - 122.40 µS/cm). We found a seasonal difference in water quality between the rainy and dry seasons. Results showed spatial variation in water quality between zones. A comparison of the mean values with water quality standards showed that Lake Tseny has good water conditions for domestic purposes and suitable habitats for aquatic fauna throughout the year. These preliminary results provide reference data on the lake's characteristics. Due to the increasing human activities in the area, regular monitoring of water quality and physical characteristics should be carried out.

The Impact of the Resort-Based Borobudur Highland Master Plan as an Integrated Tourism Area

Tourism in Indonesia has quite good potential and is one of the sectors that spurs the economy in Indonesia. Development of Borobudur Highland which is included in the five super priority tourist destinations. One of them is the construction of hotels and resorts in the Menoreh Hills, Purworejo Regency, Central Java. The master plan was made as a tourism area plan under the Borobudur Authority Agency (BOB) covering an area of ​​309 hectares (ha). This master plan consists of five zones, namely the exclusive resort zone, the entry gate zone, the adventure zone, the cultural zone and the extreme zone. There are three themes in the development of this area, namely ecotourism, cultural tourism and adventure tourism. The method used is using descriptive qualitative. Data collection techniques through interviews, observation, and documentation. The data analyzed using the SWOT matrix. The results of this research can increase the existence of tourism objects in the Purworejo and Kulonprogo areas to international class that are sustainable, educative, and provide new breakthroughs that have an impact on investment in employment and local products around the area. The threats that can occur are changes in rainwater catchment areas to become prone to landslides, loss of springs, damage to ecosystems due to logging of trees, and disruption of existing flora and fauna habitats.

Mangrove Health: A Review of Functions, Threats, and Challenges Associated with Mangrove Management Practices

Mangroves stand out as one of the most diverse and biologically significant natural systems in the world. Playing critical roles in maintaining the health and productivity of coastal ecosystems, mangroves provide a range of services and functions, including habitat for local fauna and flora, food and other goods, carbon sequestration, and protection from natural disasters such as storm surges and coastal erosion. It is also evident that mangroves face several threats, which have already led to the gradual depletion of mangrove areas worldwide. Based on the analysis of current and related historical literature and data, this review summarises mangrove functions and the threats and challenges associated with mangrove management practices. Our findings suggest that coastal development, expanded aquaculture, deforestation, climate change, and other associated implications such as eutrophication, diseases, and pollution are the major factors posing threats to mangrove sustainability. We also highlight the various challenges, such as land use conflict, a lack of stringent regulatory actions, inadequate policy and government frameworks, and a lack of community awareness, that underlie ineffective mangrove management. The implementation of inclusive and coordinated approaches involving stakeholders from different backgrounds and interests, governmental and non-governmental organisations, and academia is essential for mangrove restoration and sustainable mangrove management by adapting mitigation strategies.

Yukon ice patches: Bryophyte generation from ancient ice-entombed assemblages

ABSTRACT In Southwestern Yukon, ice patches have shown substantial retreat since the Little Ice Age (1600–1900 AD) in response to warming trends. These ice patches support unique alpine wetlands that have formed habitats for diverse flora and fauna over millennia. With ice retreat, pristine bryophyte populations are exposed beneath accumulated ancient dung. Given that bryophytes have been shown to survive extreme conditions including ice entombment and can regenerate from viable cells, emergent ice margin bryophyte and dung samples from the Granger and Gladstone ice patches were assayed for regrowth potential under growth chamber conditions. Diaspore (spore/fragment) generation of species found in the original subfossil material was indicated in 68 percent of assays, emphasizing the cyclical establishment of ancient ice patch vegetation. One of the oldest samples, dating 4036 calibrated years BP from the Gladstone ice patch margin, showed remarkable bryophyte generation from diaspores in dung. These Yukon ice patches form reservoirs of cryopreserved biota and have a critical role in maintaining alpine diversity, which provides summer refuge for caribou and other alpine fauna. Ice margin fluctuations, which bury and release populations through time, are part of a complex revegetation sequence in alpine regions that has followed deglaciation.

How wide, how much? A framework for quantifying the economic and ecological outcomes of altering riparian width on agricultural land

Creating and managing riparian buffer zones (RBZs) is regarded as a global best-practice management strategy for maintaining and improving waterway health. Agricultural land often utilises RBZs as highly productive pasture, exposing waterways to increased inputs of nutrients, pollutants, and sediment, in addition to reducing carbon sequestration and habitat for native flora and fauna. This project developed a novel approach to the application of multisystem ecological and economic quantification models to the property-scale, at low cost and high speed. We developed a state-of-the-art dynamic geospatial interface to communicate these outputs when switching from pasture to revegetated riparian zone via planned restoration efforts. The tool was developed using the regional conditions of a south-east Australian catchment as a case study but is designed to be adaptable around globally using equivalent model inputs. Ecological and economic outcomes were determined using existing methods, including an agricultural land suitability analysis to quantify primary production, an estimation of carbon sequestration using historic vegetation datasets and GIS software analysis to determine spatial costings of revegetation and fencing. Economic outcomes are presented in raw values of pasture produced and carbon sequestered, and fencing and revegetation costs can be easily altered for enhanced usability and interoperability. This tool can provide property-specific data for almost 16,000 properties in a catchment area of over 130,000 km2 and 19,600 km of river length. Our results indicated that current financial incentives for revegetation rarely cover the cost of giving up pasture, but these costs may be compensated by social and ecological outcomes achieved over time. This method provides a novel way of informing alternative management approaches, such as incremental revegetation plans and the selective harvesting of timber from RBZ. The model provides an innovative framework for improved RBZ management and can be used to inform property-specific responses and guide discussion among stakeholders.

Lakeshore vegetation: More resilient towards human recreation than we think?

AbstractLakes and their shoreline vegetation are rich in biodiversity and provide multiple functions and habitats for fauna and flora. Humans are attracted by the scenic beauty of these ecosystems and the possibilities for recreational activities they offer. However, the use of lakes for recreational activities can lead to disturbance of vegetation, threatening the integrity and functionality of shoreline areas. Recent literature reviews revealed that impacts of the seemingly harmless activities bathing and lingering on the shore on lakeshore vegetation are poorly understood. In this study, we analysed the effects of shoreline use connected with bathing on the structure, composition and diversity of lakeshore vegetation. Vegetation relevés were recorded in 10 bathing and 10 adjacent control sites in the nature park ‘Dahme‐Heideseen’ (Brandenburg, Germany). In addition visitor counts were performed. The species composition and the cover of herbaceous and shrub vegetation differed between bathing and control sites, but all sites had a high percentage of plant species not typical for the community. The vegetation parameters did not correlate with visitor counts. The results indicate that the present visitor intensity in the nature park does not impact the vegetation severely.

Influence of habitat and other factors on Largemouth Bass abundance in Lake Okeechobee, Florida

AbstractObjectiveSubmerged aquatic vegetation (SAV) is an important part of shallow lake ecosystems. It provides protective cover and foraging habitat for age‐0 and juvenile Largemouth Bass Micropterus salmoides and other small fish, creates structure and habitat for macroinvertebrates and other fauna, and can influence the physical environment by stabilizing sediments and reducing water column turbidity.MethodsFor this study, we reviewed annual abundance data for Largemouth Bass collected via electrofishing from 2002 to 2019, along with environmental covariates that included SAV cover (habitat) and turbidity.ResultAll age‐groups of Largemouth Bass were positively correlated with vascular SAV cover. Age‐0 Largemouth Bass were most abundant when SAV cover exceeded approximately 24% (9400 ha) of the littoral and nearshore area, while the juvenile and all‐ages groups were most abundant when SAV cover exceeded 20% and 12% of the area, respectively. Following major storm events, water depth and turbidity increased, SAV cover was reduced to <5% of the littoral and nearshore area, and the abundance of age‐0 Largemouth Bass was reduced more than 90%.ConclusionOnce removed from the landscape and exposed to turbid conditions, vascular SAV will reestablish only if water clarity increases and light is sufficient to support plant growth. Lowering water levels for an extended period has been shown to reduce nearshore turbidity and jumpstart the recovery of SAV in Lake Okeechobee and other shallow lakes globally. Without adequate SAV habitat, recruitment of age‐0 and juvenile Largemouth Bass will likely be suppressed. Maintaining a minimum coverage of vascular SAV (20–35%) in the littoral and nearshore area should increase the abundance of age‐0 and juvenile Largemouth Bass and provide beneficial habitat for adult Largemouth Bass and other lake fauna.

Human-Wildlife Interactions and Community Livelihoods

In developing nations, particularly in Africa, interactions between humans and animals (HWIs) are widespread as local populations heavily rely on natural resources such as forests, which serve as habitats for flora and fauna. This paper draws from a study which investigated human-wildlife interactions (HWIs) in four villages—Mvuha, Mbwade, Milengwelengwe, and Kisaki Gomero— surrounding the Selous Game Reserve (SGR). A mixed methods approach was adopted to aid data capturing from 312 households and 11 key informants. Spatial analysis was employed to depict land use and land cover changes around the SGR over time due to human influence. The results indicated that HWIs were influenced by changes in water and pasture availability caused by two elements of weather: temperature and rainfall. People in WMA-designated villages complained about the lack of employment and unfair distribution of benefits, whereby the main concern of non-WMA-designated villages was on the need for policy review, with emphasis on the holistic conservation approach. Nonetheless, bush lands have increased in recent decades at the expense of woodland due to the proliferation of human interference. The paper concludes that the intersection of community livelihoods and wildlife ecology was the most common HWI pattern observed. However, typical forms of interaction were often hostile and instigated human-wildlife conflicts.

Nothofagus pumilio regeneration failure following wildfire in the sub-Antarctic forests of Tierra del Fuego, Argentina

Abstract Wildfires on the island of Tierra del Fuego in southern Argentina are not considered to have been a historic driver of forest dynamics. However, dramatic increases in the human population of the island over the last half-century have greatly increased fire ignition sources and thus the frequency of wildfires in the region. Lenga (Nothofagus pumilio (Poep. et Endl.) Krasser) forests support diverse ecosystem services by providing habitat for endemic flora and fauna and also represent a valuable timber resource for the forest industry of Tierra del Fuego. Evaluating the impact of forest fires on lenga regeneration is important not only because lenga is a native, slow-growing species that seems to lack adaptations that would allow it to recover rapidly after fire, but also because low tree species diversity on the island of Tierra del Fuego means lenga post-fire regeneration failure may lead to ecosystem state shifts. To determine how site characteristics and fire-impacted variables modulate post-fire regeneration densities and spatial patterns in lenga forests, we installed 192 plots (160 burned, 32 unburned) in which we measured site-characteristic (e.g. aspect, elevation) and fire-impacted (e.g. basal area, canopy cover) variables and tallied seedlings and saplings. Regeneration densities were significantly lower in burned than unburned plots. This was exacerbated with increasing distance from the unburned forest edge. Increasing distance to live trees that either survived fire or were outside the burned area negatively impacted regeneration as well. Time since fire negatively affected sapling, but not seedling counts. We concluded that lenga regeneration in the interior of burned areas is largely absent, delaying and potentially preventing forest recovery. These interior areas of burned lenga forests are unlikely to regenerate closed-canopy tree cover through passive restoration alone. Active restoration may be needed in these critical areas where live legacy trees are not present.

Sensitivity Analysis of Parameters Affecting Wetland Water Levels: A Study of Flood Detention Basin, Colombo, Sri Lanka

Wetlands play a vital role in ecosystems. They help in flood accumulation, water purification, groundwater recharge, shoreline stabilization, provision of habitats for flora and fauna, and facilitation of recreation activities. Although wetlands are hot spots of biodiversity, they are one of the most endangered ecosystems on the Earth. This is not only due to anthropogenic activities but also due to changing climate. Many studies can be found in the literature to understand the water levels of wetlands with respect to the climate; however, there is a lack of identification of the major meteorological parameters affecting the water levels, which are much localized. Therefore, this study, for the first time in Sri Lanka, was carried out to understand the most important parameters affecting the water depth of the Colombo flood detention basin. The temporal behavior of water level fluctuations was tested among various combinations of hydro-meteorological parameters with the help of Artificial Neural Networks (ANN). As expected, rainfall was found to be the most impacting parameter; however, apart from that, some interesting combinations of meteorological parameters were found as the second layer of impacting parameters. The rainfall-nighttime relative humidity, rainfall-evaporation, daytime relative humidity-evaporation, and rainfall-nighttime relative humidity-evaporation combinations were highly impactful toward the water level fluctuations. The findings of this study help to sustainably manage the available wetlands in Colombo, Sri Lanka. In addition, the study emphasizes the importance of high-resolution on-site data availability for higher prediction accuracy.

Transient shifts in composition of degraded temperate native grassland following grazing exclusion

AbstractQuestionsGlobally, grassy ecosystems are threatened and are still declining in extent in many areas. Improving the management of degraded native temperate grasslands that are grazed by livestock is important to the conservation of this critically endangered ecosystem. Questions remain about the role of grazing in the management of such grasslands, particularly in the face of climate change and given the sensitivity of these systems to inter‐annual rainfall variability. Here, we investigate the effect of livestock exclusion on grassland composition.LocationTemperate grassland, Victoria, Australia.MethodsOver 9 years (2009–2017), we monitored plant functional groups in plots open‐to‐grazing or ungrazed exclusion plots within five fields of degraded native temperate grassland on private land.ResultsIn the years after grazing had been excluded, we found significant differences in cover between grazed and ungrazed plots for some functional groups (e.g. native perennial graminoids) in some years, but we did not observe long‐term divergence in cover or composition of the treatments. At the final monitoring point there were no significant differences in native or exotic species richness between the grazed and ungrazed plots. We show that the years in which differences were observed correspond with the 2010–2011 La Niña high‐rainfall event, suggesting that grazing exclusion effects are mediated by rainfall, and are likely to be evident only under certain conditions.ConclusionIn grassy ecosystems already degraded by long‐term grazing, excluding grazing has limited potential to shift plant species composition in favour of native dominance. Such grasslands may persist in the medium term in a stable but degraded state with or without continued light to moderate livestock grazing pressure. Hence, managed livestock grazing need not be incompatible with the conservation of degraded temperate grasslands particularly where biomass management is important for the maintenance of faunal habitat. However, improving the function and diversity of these degraded grasslands will seemingly require additional management, including seed addition and experimentation with alternative disturbance regimes.