Macrophyte Diversity Research Articles

Macrophyte stand complexity explains the functional α and β diversity of fish in a tropical river-floodplain

Aquatic macrophytes increase habitat complexity and influence the structure of fish communities. We investigated relations between macrophyte stand complexity and functional alpha and beta diversity of fish. We sampled fish and plants in 30 macrophyte stands with differences in density and diversity in the Parana River floodplain. The functional alpha diversity, measured as functional richness index (FRic), was calculated for each macrophyte stand. The functional beta diversity was examined using pairwise Jaccard dissimilarity as well as its turnover and nestedness components. We also partitioned functional beta diversity into contributions of single sites to overall beta diversity (LCBD) aiming to assess its relationship to macrophyte stand characteristics. We then used beta regressions and generalized dissimilarity modeling (GDM) to examine diversity patterns. As we expected, the greatest FRic occurred in stands with intermediate macrophyte density and high macrophyte diversity. The functional beta diversity responded mainly to the variation in macrophyte density, but the turnover component increased slowly at the beginning of the gradient (low density) and, after a certain point, it started to increase more rapidly. The stands that contributed the most to the functional beta diversity (higher LCBD values) were those with low and high FRic and, consequently, with lower and higher macrophyte density, as well as lowest macrophyte diversity. Our findings highlight the role of macrophytes as environmental filters that select the traits in fish communities, and the variation in fish traits is probably a result of factors such as food availability, shelter from predators and physical space for locomotion.

Wetlands and diversity of angiosperm macrophytes in wetlands of Pune district in Maharashtra, India

The wetlands and wetland macrophytes play crucial role in the ecosystem with direct as well as indirect benefits of uncountable value. A study was undertaken to document angiospermic wetland macrophytes in Pune district, Maharashtra state, India. Results of the study revealed that, there are 11 categories of wetlands in Pune district including seven natural and four man- made. These wetlands harbour 457 angiosperms belonging to 72 families. Of these, 457 taxa, 204 taxa are under different categories as per IUCN, while 253 are not evaluated. Among recorded taxa, one is ‘Critically Endangered’ (Eriocaulon santapaui), three ‘Endangered’ (Iphigenia stellata, Eriocaulon richardianum and Dimeria hohenackeri), two ‘Vulnerable’ (Isachne bicolor and Utricularia albocaerulea) and 198 taxa are ‘Least concerned’. Total 67 Indian endemic taxa are recorded from the wetlands in the study area.

Assessment of Aquatic Macrophyte Diversity and Water Quality from Jhanpa Baor in Jessore District, Bangladesh

Jhanpa Baor is a famous fresh water oxbow lake situated in Jessore district, Bangladesh. The physico-chemical parameters were analyzed from March 2021 to August 2021. Quadrates were ordered randomly and lengthening from boundary towards the lake center. The aquatic macrophytes found in each study site were listed species wise and the information was documented. A total number of 12 aquatic macrophytes were recorded from this area. The macrophytes were categorized into five morphological clusters as floating, submerged, free floating, floating creeper and emergent. The coverage of macrophytes near the periphery was higher than the central region of the lake. A number of physico-chemical analyses were conducted on the collected water samples, viz. pH (7.096 ± 0.06), electric conductivity (0.32 ± 0.01 mS/cm), temperature (32.14 ± 0.28 oC), dissolved oxygen (0.692 ± 0.12 mg/L), salinity (156 ± 8.94 ppm), water depth (10.91 ± 2.58 m), transparency (31.64 ± 3.52 cm) and phosphate (171.6 ± 4.56 µg/L).

Diversity and Distribution of Aquatic Macrophytes in Bargi Reservoir on River Narmada in Madhya Pradesh, India

Diversity and Distribution of Aquatic Macrophytes in Bargi Reservoir on River Narmada in Madhya Pradesh, India

Spatio-temporal dynamic of submerged aquatic macrophytes in Lake Sapanca

Aquatic macrophytes are one of the key components of freshwater ecosystems and contribute to ecosystem functioning and environmental sustainability. They are assumed to be an ideal biomonitoring tool in long-term monitoring programs implemented by the EU Water Framework Directive due to their sensitivity to environmental factors. Therefore, this study focuses on the evaluation of the ecological status in Lake Sapanca using macrophyte composition and abundance in order to make future predictions on the health of aquatic ecosystems and to form effective management. Submerged macrophyte assemblages related to environmental parameters were investigated from February to November of 2017. A total of 12 submerged macrophyte species were recorded in the littoral zone of the lake. The main findings on the most dominant 7 species of this community indicated significant differences among stations and seasons. They also revealed that submerged macrophyte density was shaped in relation to environmental variables, particularly temperature and nutrients. Submerged macrophyte assemblages reached their highest species number and biomass value (5312 gm?2) in summer, while no species was recorded in winter. High biomass values of these species corresponded with lower macrophyte diversity. The macrophyte index results demonstrated that Lake Sapanca is at a critical level in terms of nutrient enrichment. More frequent observation of species such as Ceratophyllum demersum and Elodea canadensis, which indicated "massive" nutrient enrichment, revealed that the ecological status of the lake varies from meso- to eutrophic at the local level.

Untangling the determinants of macrophyte beta diversity in tropical floodplain lakes: insights from ecological uniqueness and species contributions

Deconstructing beta diversity patterns into site or species contributions is a modern approach to understand the factors affecting variation in biodiversity. In this context, estimating the Local Contribution to Beta Diversity (LCBD) and the individual Species Contribution to Beta diversity (SCBD) have been shown to be a good approach to improve knowledge of the drivers of beta diversity. We examined the beta diversity of macrophytes surveyed at 49 floodplain lakes in the Pantanal Wetlands in Brazil during the dry season. We found that, unexpectedly, total species richness was not correlated to LCBD values, but the number of rare species per site was possibly related to LCBD values. Three variables from Moran’s Eigenvector Maps (MEM), water transparency and organic matter were the main variables related to LCBD values. The species with highest contributions to beta diversity were those that occurred at approximately half of the surveyed sites. The same patterns were observed when analysing macrophyte data divided by life forms. Of the life forms, floating macrophytes contributed most to beta diversity. The understanding of which factors drive variation in LCBD and which kind of species most contribute to SCBD are fundamental to performing efficient conservation and restoration programs to maintain the structural, functional and ecological diversity of the macrophyte communities in dynamic floodplain ecosystems.

Diversity and distribution of aquatic vascular macrophytes in lake Buluan, Philippines

This study aimed to determine the species composition and distribution of aquatic vascular macrophytes in Lake Buluan in Maguindanao and Sultan kudarat, Philippines. A total of ten (10) macrophytic species in 16 sampling sites were studied. In our observation, a non-native invasive species Eichhornia crassipes found to be dominant with a frequency of 81% occupying 496 hectares. The species diversity is found to be uneven and absence of submerged aquatic vegetation induces stress and disturbance in the lake ecosystem. Photographs of identified vascular macrophytes, study sites, Distribution map were provided. We recommend substantial measures have to be implemented to protect Buluan lake ecosystem against eutrophication and invasion.

Responses of Rotifer Community to Microhabitat Changes Caused by Summer-Concentrated Rainfall in a Shallow Reservoir, South Korea

Empirical studies suggest that the structural heterogeneity of aquatic ecosystem microhabitat is determined by the diversity and abundance of macrophytes. However, excessive accumulation of free-floating macrophytes on the water surface can reduce the biomass of submerged macrophytes, resulting in a relatively simplified habitat structure. We hypothesized that heavy summer rainfall disrupts the growth of free-floating macrophytes covering much of the Jangcheok Reservoir’s water surface, thereby resulting in a more complex habitat structure by allowing development of a more diverse of macrophytic community. We divided long-term (2008–2017) monitoring data (rainfall, macrophytes, and rotifers) into two groups: Rainy and Dry years, corresponding to years with annual rainfall higher and lower than the total annual average, respectively. We found that summer densities of rotifers fell sharply in Rainy years, but increased continuously in Dry years. This trend resulted in greater autumn densities in Rainy relative to Dry years, which we attributed to changes in habitat related to differential macrophyte development. Moderate disturbance of the water surface caused by high summer rainfall can promote growth of submerged macrophytes by creating large areas of open water and therefore a more complex autumnal microhabitat structure, resulting in seasonal variations in rotifer community structures and populations. Moreover, a highly complex microhabitat structure restricts foraging activity of fish (i.e., Lepomis macrochirus) that prey on rotifers. Based on these findings, we suggest that summer-concentrated rainfall plays an important role in supporting the density and species diversity of rotifers.

Impacts of artificial barriers on the connectivity and dispersal of vascular macrophytes in rivers: A critical review

Abstract Macrophytes play important functional roles in river ecosystems, providing habitat and food, as well as influencing flow, water chemistry, and sediment dynamics. They also represent an important component of river biodiversity. Artificial river barriers have the potential to disrupt macrophyte dispersal, and compromise their distribution and persistence, but little information is available compared to barrier impacts on fish and macroinvertebrates. Here, we review the mechanisms supporting dispersal of river macrophytes in rivers and evaluate the nature of barrier impacts on macrophytes. Hydrochory (dispersal of propagules by water) is the principal mechanism of downstream dispersal, while zoochory (dispersal of propagules by animals) is likely to be the most important vector of upstream dispersal and inter‐catchment transport. Most studies have focused on the impact of large structures such as dams, and the findings indicate the impact is highly context dependent. Slow‐flowing habitats upstream of dams can act as traps to drifting propagules and thereby interrupt hydrochory. However, the consequences of interrupted hydrochory for downstream populations are unclear. River regulation can result in lower macrophyte diversity, although the lentic habitats associated with reservoirs can also favour an increase in the abundance and richness of macrophyte communities. Instream barriers are unlikely to affect zoochory by birds directly, but barriers are well known to restrict fish movements, so there is considerable potential for barriers to disrupt zoochory by fish, although no empirical study has specifically examined this possibility. There is a paucity of studies examining the impacts of low‐head barriers on macrophyte dispersal. Given the influence of macrophytes on river processes, we call for further research into barrier impacts on macrophyte population dynamics in order to gain a better understanding of the consequences of river fragmentation for fluvial communities and ecosystem functioning.

Environmental factors affect macrophyte diversity on Amazonian aquatic ecosystems inserted in an anthropogenic landscape

Abstract Land use is considered one of the most serious drivers of biodiversity change. Aquatic macrophytes are sensitive to changes occurring within their physical habitat and respond at different scales to the effects of land use. Our main objective was to evaluate the effects of multiple land uses on macrophyte diversity. For that, we surveyed aquatic macrophyte richness and cover, in addition to local (water parameters and canopy cover) and landscape (land use and land cover) environmental variables. We evaluated 30 aquatic ecosystems and the results showed canopy cover was negatively correlated with temperature and land use gradient, indicating this parameter reflects land use change within sites. Species richness was affected negatively by canopy cover. Forest cover loss could change macrophyte microhabitats, increasing light resources that favor species that otherwise would not be able to occur there. Species composition was related negatively with canopy cover and water turbidity, and positively related to pH. Three species were selected as indicators of change in canopy cover, which reflects land use change within the sites. Land use change favors mostly emergent and amphibious species, and some species belonging to other life-forms that show adaptations and niche requirements that are benefited by it. Macrophyte communities could be experiencing succession, in which the appearance of invasive species could be the onset of a reduction in diversity as land use consequences become abrasive. We recommend different aspects of macrophyte communities (e.g. species richness, composition, life-form diversity, presence of invasive species, and taxon-specific niche requirements) to be considered when creating indexes of integrity, and when making management decisions regarding the preservation of Amazonian freshwater ecosystems, due to their great potential as indicators, and in order to maintain overall aquatic biodiversity.

Diversity and distribution patterns of aquatic macrophytes in selected ecosystems of south western Nigeria

AbstractThe present study investigates the macrophytes diversity from selected aquatic ecosystems in South‐Western Nigeria using quadrat method. The survey revealed two major aquatic ecosystem types (mangrove and freshwater swamp) and recorded a total of 83 species belonging to 77 genera and 41 families. Three species (Sacciolepis africana, Ipomoea asarifolia and Commelina diffusa) were found present in all the surveyed areas. However, species such as Acrostichum aureum, Avicennia germinans and Rhizophora racemosa were restricted in its distribution. Poaceae and Ludwigia were the dominant family and genus, respectively. In addition, our study recorded Hallea ledermannii classified as vulnerable by IUCN Red List. Diversity analysis revealed high species richness in all the studied locations especially in Lagos State. Similar diversity pattern was observed for Osun and Oyo States. Further, our results reflect that macrophytes assemblages in South‐Western Nigeria could be influenced by human activities. Hence, we recommend further studies that would test hypothesis on how human activities affect the diversity and distribution of flora in the area. Additionally, conservation of the aquatic environments of the region appears necessary. The findings of this study provide insights on the patterns of macrophyte diversity in South‐Western Nigeria, thus, forms a guideline for initiating effective conservation policies in the area.

Macrophyte Diversity and Complexity Reduce Larval Mosquito Abundance.

The role of aquatic arthropod diversity and community interactions of larval mosquitoes are important for understanding mosquito population dynamics. We tested the effects of aquatic macrophyte diversity and habitat structural complexity in shaping the predator and competitor invertebrate communities associated with mosquito larvae. Experimental mesocosms were planted with live aquatic macrophytes and allowed to be naturally colonized by local invertebrates. Results indicated a positive effect of macrophyte diversity on competitor diversity and a negative effect on predator diversity. In turn, predator diversity negatively impacted mosquito abundance through a direct effect, while competitor diversity showed an indirect negative effect on mosquito larval abundance through its positive effect on predator diversity. The enhancement of aquatic macrophyte diversity and structural complexity has practical applications for the reduction of mosquito populations in managed systems where complete source elimination is not possible.

Diversity and abundance of macrophytes of streams under different anthropogenic influences in the Buea municipality, southwestern Cameroon

Diversity and abundance of macrophytes of streams under different anthropogenic influences in the Buea municipality, southwestern Cameroon

Diversity and abundance of macrophytes of streams under different anthropogenic influences in the Buea municipality, southwestern Cameroon

Macrophytes can occur as submerged, floating or emergent. They provide not only important structural supports in streams and river habitats, but also absorb and sequester pollutants, provide primary food production, nutrients and habitats to a wide range of macro and micro-organisms living in and around lotic sites. Their existence is however threatened by both anthropogenic and natural stresses. This study aimed to document macrophyte diversity and abundance in streams under different anthropogenic influences in Buea, southwestern Cameroon. Floristic surveys were carried out using 500 m long transects laid along the different streams. Plants encountered were identified and confirmed at the Limbe Botanic Garden Herbarium. One hundred and ten species belonging to 38 families and 83 genera were recorded. There were no floating species and only one stream had submerged species (Vallisneria spiralis L and Crinum calamistratum Bogner & Heine). The highest number of families (26), genera (58) and species (70) were obtained in Ndongo while the least of these taxa were obtained in Bulu (16, 35 and 39, respectively). Overall, Asteraceae and Poaceae were the most abundant, suggesting anemophilic dispersals. However, individual species abundances varied with streams. The highest diversity index (0.945) was in Wongangjio while the least (0.760) was in Nange, suggesting that waste discharge from car wash might influence species diversity negatively. The macrophyte composition was made up of obligate and non-obligate species as a consequence of anthropogenic influences. These results constitute baseline data for the area that can be exploited for further research and monitoring.

Comparative study on physicochemical status and diversity of macrophytes and zooplanktons of two urban ponds of Chandannagar, WB, India

Present investigation has made an attempt to assess the variations in physicochemical status of two urban ponds (constructed boundary: Pond A and natural boundary: Pond B) of Chandannagar and also established the variations in the diversity of macrophytes and zooplankton of the study areas during winter (Nov–Dec, 2017). Limnological parameters recorded from two spots collected in three phases, such as temperature, pH, transparency, conductivity, DO, BOD, total dissolved solids (TDS), total suspended solids (TSS), total alkalinity, total hardness and chloride, were evaluated. From this observation, it is reported that there are marked variations in different water quality parameters of two urban ponds during the study period. The value of water temperature in Pond A and B was 22.0 and 21.3 °C, respectively. pH value (7.9) was highest in Pond B. Pond B water was more turbid than Pond A. The highest values of other parameters like conductivity (218.50 µS/cm) DO (8.47 mg/l), BOD (5.69 mg/l), TDS (135.19 mg/l), TSS (67.60 mg/l), total alkalinity (181.15 mg/l), total hardness (145.66 mg/l) and chloride (58.94 mg/l) were found in case of Pond B. Maximum macrophytic vegetations were found in Pond B in comparison with Pond A. The study of the zooplankton community reveals that the maximum occurrence of rotifers in Pond B indicates pollution status.

Negative correlations between native macrophyte diversity and water hyacinth abundance are stronger in its introduced than in its native range

AbstractAimWe tested the hypothesis that the diversity and abundance of aquatic macrophytes are negatively related with Eichhornia crassipes abundance in its introduced range, but not in its native range.LocationUpper Paraná River Floodplain, Brazil and Southeast China.MethodsWe sampled aquatic macrophytes patches in Brazil (native range) and China (introduced range) along a biomass gradient of E. crassipes. For each patch, we obtained values of species richness and aquatic macrophytes percentage cover, as response variables in regression models. We also used species accumulation curves to quantify the total plot diversity in dominated and non‐dominated plots for both countries. Finally, we compared the influence of E. crassipes dominance on community composition and beta diversity with Permanova and Permdisp, respectively.ResultsThe regression analyses revealed a negative correlation between macrophyte richness and cover and E. crassipes biomass only in the introduced range. The cumulative number of species decreased at a higher extent in plots dominated by E. crassipes in China, compared with Brazil. Also, species composition changed and beta diversity decreased in the dominated plots in China, but not in Brazil.Main ConclusionsThe reduction of all diversity attributes related to E. crassipes probably results from its engineer species role, which decreases littoral region habitat heterogeneity and affects rare species in the introduced range. Differences between countries may be associated with impacts of water hyacinth on native macrophytes as this plant grows very fast and is highly competitive. Although less probable, biotic resistance at the establishment phase of water hyacinth in sites with higher number of native species is also a possibility. Regardless of the main mechanism explaining our patterns, it is suggested that invasion by water hyacinth is a cause for concern for its higher impacts in the introduced ranges than the native ranges.

Aquatic macrophytes: ecological features and functions

The article is devoted to the analysis of current data on the ecological features and functions of the aquatic macrophytes which are important components of aquatic and wetland ecosystems across the globe. Macrophytes comprise a taxonomically diverse group of macroscopic plants including representatives of vascular aquatic plants, bryophytes, as well as green macroalgae and charophytes. An assemblage of macrophytic vegetation consists of emergent species whose vegetative parts emerge above the water surface, submerged and floating species, with each ecological group having specific features in morphology and physiological processes. A wide range of the adaptive mechanisms developed by aquatic macrophytes at the morphological, physiological, and biochemical levels enables them to inhabit various types of freshwater, brackish-water, and marine habitats. Macrophytes are an important component of aquatic food webs and perform a host of ecological functions in water ecosystems. The main ones are synthesis and storage of organic compounds and oxygen release, absorption and accumulation of chemical elements, water filtration and detoxification of pollutants, release of biologically active compounds involved in interspecies communications, provision of food, shelter and feeding places for aquatic animals, impact on the hydrological regime of water bodies, etc. A wide array of macrophyte species aresed in various human activities, including bioindication of water quality, phytoremediation of contaminated water bodies and wastewater treatment. However, human activities leading to surface water pollution, eutrophication and global warming have led to a concomitant decrease in macrophyte diversity in many freshwater ecosystems and in marine environment. Therefore, proper management of aquatic and wetland ecosystems, including their monitoring and control, is a prerequisite for a successful conservation of habitats and species richness of the aquatic macrophytes.

Aquatic macrophyte diversity, distribution, and control in coastal Southern Ghana, with priority on non-native invasive species

Abstract. Ernest A, Ameka GK. 2019. Aquatic macrophyte diversity, distribution, and control in coastal Southern Ghana, with priority on non-native invasive species. Ocean Life 3: 87-93. Southern Ghana has been the focus of research into the variety and distribution of aquatic macrophytes, focusing on invasive species. Greater Accra, the Central Region, the Ashanti Region, the Eastern Region, the Volta Region, and the Western Region were all included in the study. Voucher specimens were obtained from 44 locations and submitted to the Ghana Herbarium. Sixty-two species of aquatic macrophytes were found, representing 48 genera and 30 families. All the aquatic macrophytes seen were classified into two groups, those that were invasive and those that were not; these were further divided into their respective families. With nine species, the Cyperaceae family emerged as the contender. IUCN (2004) criteria were used to determine if a species met the definition of an invasive. Because of this, the observed aquatic macrophytes were classified as invasive or noninvasive. Fifty-two aquatic species were found to be noninvasive, whereas eleven were found to be invasive. The aquatic macrophytes' life histories were also analyzed. There were 41 emergent species (67%), 11 free-floating species (17%), eight submerged species (13%), and two floating-leaf species (3%). Eleven types of invasive aquatic plants were found, and distribution maps were made for each. In the southern region of Ghana, Pistia stratiotes were found in seven different locations, making it the most widespread invasive aquatic plant in the region. All 62 invasive and noninvasive species were recorded in a database. Among these were the species' scientific and colloquial names and their genus and family, description, reproduction, habitat, distribution, and uses. Each method of control for invasive aquatic macrophytes was reviewed to make advantage of the most effective strategies for their management and eradication.

CHARACTERIZATION OF THE BIOTIC (MACROPHYTES AND MACROINVERTEBRATES) AND ABIOTIC FACTORS OF PANTANAL PONDS IN THE MIRANDA RIVER FLOODPLAIN

The Pantanal has an exuberant biodiversity that is constantly regulated by the dynamics of the climate and by the flood pulses. The objective of this work was to characterize and evaluate the biotic (macrophytes and macroinvertebrates) and abiotic factors (pH, temperature, dissolved oxygen, conductivity, total dissolved solids, water turbidity, chlorophyll a and pheophytin-a) of Pantanal ponds depending on the dry or rainy season. Therefore, five ponds with different characteristics were analyzed and five samples of water were collected during the dry and rainy season. For sampling of the macrophytes and collection of the macroinvertebrates we used hand nets (area of 0,09m2, opening of 5000 μm). This was done in order to observe seasonal difference in pH, chlorophyll-a and pheophytin-a and spatial differences between dissolved oxygen, electrical conductivity, turbidity, chlorophyll a and pheophytin-a was observed. The aquatic macrophyte Eichornia azurea ( Commelinales, Ponteridaceae) showed high dominance and relative vegetation cover in at least three ponds, which was also related to higher values of macroinvertebrate biomass. On the other hand, the ponds that presented low dominance or absence of E. azurea presented high diversity of aquatic macrophytes. However, these intrinsic biological characteristics of the ponds altogether with the abiotic parameters demonstrated that there are distinct patterns in the dynamics of these ecosystems during the drought and flood regimes.

Bridging population genetics and the metacommunity perspective to unravel the biogeographic processes shaping genetic differentiation of Myriophyllum alterniflorum DC.

The degree to which dispersal limitation interacts with environmental filtering has intrigued metacommunity ecologists and molecular biogeographers since the beginning of both research disciplines. Since genetic methods are superior to coarse proxies of dispersal, understanding how environmental and geographic factors influence population genetic structure is becoming a fundamental issue for population genetics and also one of the most challenging avenues for metacommunity ecology. In this study of the aquatic macrophyte Myriophyllum alterniflorum DC., we explored the spatial genetic variation of eleven populations from the Iberian Plateau by means of microsatellite loci, and examined if the results obtained through genetic methods match modern perspectives of metacommunity theory. To do this, we applied a combination of robust statistical routines including network analysis, causal modelling and multiple matrix regression with randomization. Our findings revealed that macrophyte populations clustered into genetic groups that mirrored their geographic distributions. Importantly, we found a significant correlation between genetic variation and geographic distance at the regional scale. By using effective (genetic) dispersal estimates, our results are broadly in line with recent findings from metacommunity theory and re-emphasize the need to go beyond the historically predominant paradigm of understanding environmental heterogeneity as the main force driving macrophyte diversity patterns.