Measures Of Species Diversity Research Articles

Slugs Count: Assessing citizen scientist engagement and development, and the accuracy of their identifications

Abstract How accurately can citizen science participants identify species, and can the information they provide be used to calculate accurate estimates of species richness, abundance and diversity measures? In this paper, we address these questions using data from a citizen science project assessing slug species diversity in gardens. Sixty participants were selected from over 2700 applicants across Britain to sample their gardens regularly for slugs following a standardised method. All slugs collected during the 30‐min search were posted to the lead investigator for verification throughout the 12‐month project. The resulting data were analysed to explore how accurate participants were in identifying slugs and whether this improved over the study period. Prior experience in slug identification was evaluated as a predictor of accuracy. Participants overestimated slug abundance and species richness, which led to overestimates in species diversity indices, illustrating the importance of verification in citizen science projects involving identification. Accuracy of slug identifications increased significantly over time in quantitative analysis of ecological data. However, self‐defined prior experience of identifying slugs before participation was not a good predictor of participant accuracy. Participants reported perceived improvement in slug identification skills to an evaluation survey after the project. However, confidence in identifying and explaining identification of slugs was lower than confidence in understanding and explaining other new science topics. This citizen science approach, including expert verification of physical specimens, illustrates how this method can be used successfully to provide accurate data on species' abundance and richness, alongside improving identification skills among the public for an understudied taxon. Continued engagement and feedback for participants is key in retaining citizen science participation in a project of this type, particularly if the taxon is challenging to identify correctly to species. Read the free Plain Language Summary for this article on the Journal blog.

Fish biodiversity in modified ecosystems: a case study of Nigeria's Challawa and Tiga dams in the Challawa and Kano rivers

River impoundment is usually accompanied with consequences of alteration in the hydrological system and change in the biodiversity composition of the ecosystem. This study investigated the impact of the dams built on Challawa (that is, Challawa George-Dam) and Kano (that is, Tiga Dam) on the fish biodiversity of the reservoir and below-dam sections of the two rivers. Fish sampling was done using long lines, Malian traps, cast and gill nets from stations on the reservoir and below-dam sections of the rivers. Ten fish species were identified from the reservoir and the below-dam sections of Challawa River belonging to nine families and four orders. Fish communities of the reservoir and below-dam sections of Kano River consisted of 28 species belonging to 12 families and 7 orders. Results of the Shannon diversity index (H^') indicated that the two reservoirs have relatively higher fish species diversity measures (that is, Challawa=1.948 & Kano=2.294) than the below-dam parts (that is, Challawa=1.833 & Kano=2.247) of their respective rivers. Non-metric Multidimensional Scaling (NMDS) analysis produced two-dimensional maps with stress values of 0.0554 and 0.0537, an indication that the model provided good representation of the original data in reduced-dimensional space. The ordination map indicated wide dissimilarities between fish communities of the impounded and below-dam sections. Furthermore, a one-way analysis of similarity indicated significant difference (P=0.0001) and high dissimilarities (R=0.643) between fish communities in the two sections of Challawa River and also in Kano River (P=0.001, R=0.929). Analysis of Similarity Percentage indicated 74.45% of the dissmilarities between fish communities in the two sections were cummulatively contributed by four species in Challawa River and 72.18% by five species in Kano River. The distinct differences in fish abundance and richness between the two sections is ascribed to increased ecosytem productivity often associated with the inundated portion of dammed river. It is recommended that more water flow across the dams should be encouraged as a mitigating measure to boost basin sizes of the rivers at the below-dam sections. Key words: Diversity, dam, impound, reservoir, community, freshwater and fish species

Species diversity, ecological characteristics and conservation measures of seahorses (<i>Hippocampus</i>) in China’s waters

Species diversity, ecological characteristics and conservation measures of seahorses (<i>Hippocampus</i>) in China’s waters

Implications of irregular shelterwood system on regeneration and species diversity of Sal (Shorea robusta Gaertn. f.) forest in Nepal

Silvicultural systems are essential for effective forest management and utilize the resources by conserving biodiversity, health, and valuable services forests offer to society. However, Nepal faces a significant knowledge gap due to the limited data on the effect of silvicultural systems and forest management practices on tree diversity and regeneration. Therefore, this study was conducted to assess the effects of canopy opening on natural regeneration and species diversity of Sal (Shorea robusta Gaertn. f.) forest in comparison to managed and control blocks in the southern plains of Nepal under irregular shelterwood systems. The vegetation sampling was carried out by the quadrat method (plot of 10 m* 10 m) for studying 48 plots in both managed and control forest areas. The Shannon-Wiener Index and the Simpson Index were used to measure species diversity, whereas Margalef's index was used to measure species richness. Dominant tree species in both managed and control forest areas were identified through the Important Value Index (IVI). The seedling and sapling density of Sal was found to be significantly higher (p < 0.05) in managed blocks. Seedlings of Sal from the seed origin were notably more abundant in the managed block (p < 0.01), whereas those from coppice origin exhibited higher numbers in the control block (p < 0.01). Sal was found to be dominant species in both managed block (IVI = 199.94) and control (IVI = 108.34). The species diversity and richness were significantly declining in the managed forest (p < 0.01) with higher species dominance in comparison to the control blocks. Our study found a positive correlation of canopy cover with species diversity (r = 0.69, p < 0.01) and richness (r = 0.59, p < 0.01) whereas a negative correlation with seedling (r = −0.43, p < 0.01) and sapling density (r = −0.16, p < 0.01). The application of the irregular shelterwood system in study area has effectively promoted natural Sal regeneration while concurrently reducing species diversity. To strike a balance between timber production and biodiversity conservation in these forests, further research focusing on moderating felling intensity within the irregular shelterwood system is strongly recommended.

Effects of seining effort on estimates of fish diversity in a sand-bed river

Changes in species diversity can be an indicator of ecosystem disturbance, impairment, or recovery. Estimating sampling effort needed to adequately represent stream fish assemblages is necessary for informing conservation actions. Increased sampling intensity can increase species detection, affecting the accuracy and precision of biodiversity indices. Seining is commonly used in fish surveys in sand-bottomed streams of the western USA. Here, we sampled 20, 200-m long stream sites each with 40 consecutive seine hauls to determine how increased within-site effort affected measures of species diversity. An average of 10 seine hauls were required to collect 75% of species present at sites in 40 seine hauls, while 18 seine hauls were required to collect 100% of species observed at a site sampled with 40 hauls. Simpson’s diversity index was highly variable when fewer than 7 seine hauls were performed at each site but stabilized when effort was > 15 seine hauls per site. Total dissimilarity and β-diversity components were variable under low sampling effort and also stabilized when effort reached 15 seine hauls per site. However, sampling with more than 18–20 seine hauls per site yielded few additional species. In shallow, sand-bed streams, we suggest sampling with < 5 seine hauls per 200 m of stream can result in unreliable estimates of α-diversity and variation in β-diversity. Increased effort of 15–20 seine hauls per 200 m of stream captured nearly all species present in 40 hauls per 200 m and stabilized species evenness and β-diversity indices.

Observer error in grassland vegetation surveys: effects on species diversity metrics and species–abundance relationships

AbstractWe investigated the effect of observer error on four commonly used species diversity measures: species richness, Shannon–Weiner diversity, Shannon–Weiner evenness and Simpson’s index of diversity. We also evaluated how observer error affects inferences derived from multivariate analyses of species–abundance relationships as determined by non-metric multidimensional scaling (NMS) ordination. Grassland vegetation was sampled by three different botanists at two national park units in Missouri and Kansas, USA. The same plots were sampled by two of the botanists, who compiled lists of species composition and estimated foliar cover. Differences in the data records were then compared. Pseudoturnover (i.e. apparent turnover due to observer error) ranged from 17.1% to 22.1%, and differences in cover class estimation ranged from 21.5% to 30.5%. The percentage difference in species diversity measures between pairs of observers depended on how data were summarized, but were always &amp;lt;20%, and often &amp;lt;10%. Based on these results, species diversity metrics are affected to a relatively smaller extent by observer error than turnover indices. Turnover indices, however, contain more information because they track individual species, whereas species are interchangeable in most species diversity indices. Thus, less of the error is identified because of how species diversity indices are calculated. NMS ordinations revealed that while the characterizations of some plots by different observers were similar, differences between observers’ records for other plots resulted in greater separation in ordination space. Points representing one observer’s records were often shifted in ordination space in the same direction compared with the other observer.

Updated estimates of biotic diversity and endemism for Madagascar—revisited after 20 years

AbstractThe terrestrial and marine biotypes of Madagascar are critical priorities for conservation, with almost unparalleled levels of endemism, species diversity and human threat for a land area of its size. Field inventories and molecular-based research conducted from the mid 1980s to present have greatly expanded knowledge of the country's biota, for some groups with nearly exponential growth in measures of species diversity. I provide updated measures of estimated species diversity between a book with 289 contributors, published in 2003 (The Natural History of Madagascar), and a full-scale update with 539 contributors, published in 2022 (The New Natural History of Madagascar). I compare biodiversity information presented in the new book with data from the earlier book, providing insight into scientific advancements, and revised estimates of species richness and endemism of a range of taxonomic groups.

Composition of Mangroves and Mangrove Associates in Barangay Ata Atahon, Nasipit, Agusan del Norte, Philippines

Mangroves are essential components of the coastal biome and have an extremely productive ecosystem. It provides benefits for both the environment and humans. Valuation of the diversity and species composition plays a crucial role in the conservation and protection. This study aimed to assess the composition of mangroves and mangrove associates in Barangay Ata-Atahon, Nasipit, Agusan del Norte, Philippines. Three sampling stations were established with a 50-meter interval in every station. Transect lines of 50 meters were laid perpendicular to the shoreline. The results show that 19 species of mangroves and 5 mangrove associates were recorded. Ceriops decandra was found to be the dominant species with 303 individuals and constituting 36% of the entire mangroves population. While Camptostemon philippinensis, Rhizophora apiculata, Rhizophora mucronata had the lowest number of individuals and made up a combination of 5%. In mangrove associates, Avicennia rumphiana made up 47% of the population and was followed by Avicennia marina (40%). This implied that the study area is less diverse based on the observed species when compared to the 46-mangrove species found in the Philippines alone. Necessarily, reforestation and conservation efforts must be attained to fill the gaps between the community and mangrove sustainability. Thus, determining the species diversity and composition measures ecological status. Mitigations and ecological management must be enacted by the locality to further conserve the mangrove ecosystem.

Assessing tree species diversity in forest ecosystems: A new approach

The significance of biodiversity research is to understand the structure and function of the community, and then to protect and monitor the community. The metric of biodiversity is the base of biodiversity conservation. Species richness and evenness are the most common descriptors of biodiversity. Whether it is diversity information measure, probability measure or geometric measure, they all express the combination of species richness and evenness in different ways. This study presents a new biologically meaningful measure of species diversity, which evaluates species richness and evenness independently, designated as DRE. The novelty of our method is to use “absolute discrepancy” to express the dissimilarity between the observed community and the uniform distribution community with the same species composition and same abundance of each species, and then measure the species evenness. The logarithmic transformation of the species number is used to measure species richness with values ranging between 0 and 1. We test the performance of this measure using simulated data and observations of natural and planted forests in different climatic zones. The results showed that the new diversity index (DRE) has superior statistical qualities compared with the traditional indices. Especially, in extremely uneven communities, the new measure describes the causes of diversity changes than the traditional DRE. In addition, DRE is more sensitive to the abundance changes of rare species in the simulated community, and the interpretation of the results is more intuitive and meaningful. It is an improved method to evaluate the species diversity of any ecosystem.

Long-Term Changes in Abundance and Composition of Forest-Floor Small Mammal Communities in a Landscape with Cumulative Clearcutting

Responses of forest-floor small mammals to clearcutting are species-specific with generalists occupying a range of habitats, and specialists persisting on clearcuts for variable periods. We investigated the responses in abundance and species composition of small mammal communities to cumulative clearcutting of coniferous forests on a landscape that had four independent clearcutting events (Periods 1 to 4) over a 42-year interval from 1979 to 2020 in south-central British Columbia, Canada. We ask if the small mammal communities have changed significantly over these decades owing to removal of old-growth forest by clearcut harvesting. Hypotheses (H) predicted that the small mammal community would (H1) increase in abundance, species richness, and diversity on new clearcuts owing to the availability of early seral post-harvest habitats from cumulative clearcutting; and (H2) have higher mean abundance, species richness, and species diversity in clearcut than uncut forest sites, owing to availability of vegetative food and cover. A third hypothesis (H3) predicted that abundance of (i) early seral vegetation (herbs and shrubs) and (ii) small mammal populations, will be greater in ungrazed clearcut sites than in those grazed by cattle (Bos taurus). Mean total numbers of small mammals on new clearcuts declined in Periods 3 and 4, and hence did not support the abundance part of H1. Much of this decline was owing to low numbers of the long-tailed vole (Microtus longicaudus) and meadow vole (M. pennsylvanicus). Two generalist species: the deer mouse (Peromyscus maniculatus) and northwestern chipmunk (Neotamias amoenus), contributed to high mean species richness and diversity in Periods 2 and 3 before these metrics declined in Period 4, and hence partly supported H1. The similarity in mean total numbers of small mammals in Periods 2 to 4 did not support the abundance prediction of H2 that total numbers would be higher in clearcut than uncut forest sites. Higher mean species richness (Periods 2 and 3) and diversity (Period 3) measurements on clearcut than forest sites, particularly in the early post-harvest years, did support these parts of H2. The vegetation part (i) of H3 was not supported for herbaceous plants but it was for shrubs. The small mammal part (ii) of H3 that populations would be higher in ungrazed than grazed clearcut sites was supported for abundance but not for species richness or diversity. The decline and near disappearance of both species of Microtus was possibly related to the reduction in plant community abundance and structure from grazing (at least for shrubs) and potentially from drought effects associated with climate change. Loss of microtines from these early seral ecosystems may have profound negative effects on various ecological functions and predator communities.

Species and functional diversity of direct‐seeded vegetation declines over 25 years

SummaryThe re‐establishment of native vegetation on disturbed land has been adopted widely as a form of ecological restoration in the past few decades. It is often suggested that establishing native plantings will lead to increasing biodiversity at restoration sites over time. However, this prediction has not been tested over long periods. Now that some pioneering projects and monitoring programs have become older, it is possible to quantify the long‐term benefits of native vegetation plantings. We asked how the plant diversity and function of 12 biodiverse native vegetation plantings has changed over approximately 30 years. We found that sites declined in measures of functional and species diversity over time. Shorter‐statured woody species were not as common at older sites. Surprisingly, sites initially seeded with a greater richness of species did not have higher standing richness at any later census period. While all sites produced net native biodiversity benefits relative to the exotic pastures they replaced, ongoing management and monitoring will be needed to ensure they continue to do so. Understanding the relationship between ageing native vegetation plantings and other components of the ecosystem (e.g., mammals, birds, invertebrates, soil, microorganisms) is a priority. Our results suggest that recruitment barriers in ex‐agricultural ecosystems are high and that the biodiversity benefits provided by shorter‐lived species will only be transient without ongoing management of these systems. Research confronting these recruitment barriers is a priority, and managers (and funders) of these kinds of restoration projects may need to be prepared for ongoing management of sites to promote lost components if they are desired as continual features of these ecosystems.

Diversity-productivity relationships in forests of the southeastern United States: Leveraging national inventory data and tree functional traits

Numerous studies have evaluated the relationship between tree species diversity and productivity, with general trends suggesting a positive relationship. While most studies only use species richness, this study also analyzed how productivity changes with functional diversity and Shannon-Wiener's diversity index, to compare the impact of these different indicators of tree species diversity. This study used data from the USDA Forest Service Forest Inventory and Analysis (FIA) database collected in Alabama, Louisiana, and Mississippi to estimate plot-level productivity and diversity. Structural equation modeling was used to determine the strength of the relationship between different measures of tree species diversity and forest productivity directly and indirectly. This study found that species richness had the greatest influence on forest productivity, but it was largely an indirect effect mediated by stand density. Functional diversity did not have a substantial relationship with productivity while Shannon- Wiener's diversity index was negatively related to productivity when modeled with the other diversity indicators and mediated through stand density. The methodology of this research provides a framework for a similar analysis expanded spatially to other regions of the US to include more forest types for comparison of trends with the use of FIA data.

Comparison of the predictive ability of spectral indices for commonly used species diversity indices and Hill numbers in wetlands

The development of near-Earth remote sensing platforms, such as unmanned aerial vehicles (UAV), have provided new opportunities for wetland plant diversity monitoring. Most previous studies on the relationship between spectral and species diversity have focused on the development and use of spectral indices. However, commonly used species diversity indices may not be the best choice for spectral-species diversity research. In this paper, high spatial resolution multispectral images of freshwater marsh were obtained based on UAV in Sanjiang National Nature Reserve, Northeast China, and the commonly used species diversity indices (Richness, Shannon, and Gini-Simpson) and Hill numbers were calculated based on 135 quadrats information obtained from field surveys. The mean value of NDVI (NDVIMEAN), its standard deviation (NDVISD) and coefficient of variation (NDVICV) of each quadrat were calculated based on multispectral imagery as a proxy for the spectral indices of the quadrats. The univariate and multivariate linear models were employed to test the predictive ability of NDVI-related indices for commonly used species diversity indices and Hill numbers. The results showed that the predictive ability of NDVIMEAN for species diversity indices was limited, and the combined use of NDVIMEAN and NDVISD significantly improved the predictive ability of species diversity. The predictive ability of NDVI-related indices to Hill numbers is better than that of commonly used species diversity indices. Commonly used species diversity indices can only represent one or several “point” of the community species diversity, the Hill numbers provide a continuous measure of community species diversity, which can balance the inconsistency between the abundance and coverage of species in the community. Previous spectral-species diversity studies might not have shown the real predictive ability of species diversity based on NDVI-related indices. Our study provides innovative ideas for the selection of species diversity indices in future spectral-species diversity studies.

Grassland type and seasonal effects have a bigger influence on plant functional and taxonomical diversity than prairie dog disturbances in semiarid grasslands.

Prairie dogs (Cynomys sp.) are considered keystone species and ecosystem engineers for their grazing and burrowing activities (summarized here as disturbances). As climate changes and its variability increases, the mechanisms underlying organisms' interactions with their habitat will likely shift. Understanding the mediating role of prairie dog disturbance on vegetation structure, and its interaction with environmental conditions through time, will increase knowledge on the risks and vulnerability of grasslands.Here, we compared how plant taxonomical diversity, functional diversity metrics, and community‐weighted trait means (CWM) respond to prairie dog C. mexicanus disturbance across grassland types and seasons (dry and wet) in a priority conservation semiarid grassland of Northeast Mexico.Our findings suggest that functional metrics and CWM analyses responded to interactions between prairie dog disturbance, grassland type and season, whilst species diversity and cover measures were less sensitive to the role of prairie dog disturbance. We found weak evidence that prairie dog disturbance has a negative effect on vegetation structure, except for minimal effects on C4 and graminoid cover, but which depended mainly on season. Grassland type and season explained most of the effects on plant functional and taxonomic diversity as well as CWM traits. Furthermore, we found that leaf area as well as forb and annual cover increased during the wet season, independent of prairie dog disturbance.Our results provide evidence that grassland type and season have a stronger effect than prairie dog disturbance on the vegetation of this short‐grass, water‐restricted grassland ecosystem. We argue that focusing solely on disturbance and grazing effects is misleading, and attention is needed on the relationships between vegetation and environmental conditions which will be critical to understand semiarid grassland dynamics under future climate change conditions in the region.

Assessing Ecological Recovery of Reclaimed Well Sites: A Case Study From Alberta, Canada

Empirical evaluations of reclamation success are critical for understanding the speed of ecosystem recovery and improving best practices. In this study, we provide a quantitative evaluation of the effectiveness of past (pre-1995) and current (2010) reclamation criteria in creating functioning forest ecosystems on former industrial sites in boreal Alberta, Canada. We compared ecological indicators of ecosystem recovery (vegetation structure and soil properties) on mineral surface leases (MSLs) certified to the pre-1995 or 2010 reclamation criteria with nearby reference areas recovering from harvest (CUT) or fire (FIRE) disturbances. Six CUT and FIRE sites were chosen to compare six 1995MSLs and five 2010MSLs. Averaging 8 years since reclamation, most of the 2010MSLs were characterized by many of the same vegetation structure and soil properties as the FIRE and CUT sites. The 1995MSLs tended to support more agronomic species, notably grasses and non-native forbs, and fewer shrubs, trees, and native forbs than CUT or FIRE sites. Sites with the greatest coverage of herbaceous species (native and non-native grasses as well as non-native forbs) were the most ecologically impaired sites, based on the extreme deviation from reference site conditions. Based on these results, 2010 reclamation criteria appear to be more effectively promoting ecosystem recovery on reclaimed industrial sites than the pre-1995 criteria. While this case study illustrated the potential benefits of straightforward changes to reclamation criteria in terms of including metrics around soil quality and conservation, woody stem requirements and native plant coverage, there is ultimately always room for improvement. For jurisdictions where the objective of the criteria is to restore a forest ecosystem, including criteria geared toward tree establishment would likely be of value in ensuring the speedy return to a forest canopy state. Adding criteria with measures of native plant species diversity may also be of utility as it is well understood that having plant diversity is also a beneficial metric in creating a more resilient vegetation community.

Calculating forest species diversity with information-theory based indices using sentinel-2A sensor's of Mahavir Swami Wildlife Sanctuary.

Tropical forest serves as an important pivotal role in terrestrial biological diversity. The present study makes an attempt to identify the concentration of species among tree diversity in Mahavir Swami Wildlife Sanctuary, Bundelkhand, India. Four important ecological indicator indices namely Shannon-Weiner index (H'), Simpson's diversity (D), Margalef index (SR) and Pielou's (J) indices were make the most for species diversity measurement. The research outcomes revealed that Shannon-Weiner diversity index (H/) was found to be the best index for assessing species richness while Simpson's diversity (D) index was more suited for determining species diversity. The Shannon-Weiner index value calculated for different transects not only represent the species richness but also the species evenness in each transect. The potential application of forest diversity can be used a mechanism for forest management. The methodology will retrofit better policy implementation for maintaining the health of forest species in Mahavir Swami Wildlife Sanctuary and can be applied on other reserve forest of socio-ecological significance.

Methods and development trend for the measurement of plant species diversity in grasslands.

Plant species diversity is one of the critical factors for maintaining multi-function and stability of terrestrial ecosystem. We reviewed the traditional methods for measuring plant species diversity of grassland (PSDG), and then introduced the new ideas and methods used for PSDG monitoring. Traditionally, PSDG monitoring depended heavily on ground-based investigation, which usually required large amounts of time, labor, and cost, and therefore was only suitable for small scale investigation. Grassland plant species were typically small in size and highly mixed. It was difficult to identify and measure by remote sensing due to the limitation of resolution. Consequently, most studies on PSDG were based on remote-sensing retrieval or habitat simulation. Characterized with high spatial-temporal resolution, flexible and low cost, the unmanned aerial vehicle (UAV) technology was regarded as the bridge between ground-based investigation and satellite remote sensing. It could be the breakthrough for monitoring PSDG accurately at large scales. In the future, we should establish PSDG monitoring network by combining the fixed monitoring sites and dynamic monitoring sites of UAV and satellite remote sensing, and integrating UAV and automatic target recognition organically.

The recovery of functional diversity with restoration

Ecological restoration aims at recovering biodiversity in degraded ecosystems, and it is commonly assessed via species richness. However, it is unclear whether increasing species richness in a site also recovers its functional diversity (FD), which has been shown to be a better representation of ecosystem functioning. We conducted a quantitative synthesis of 30 restoration projects and tested whether restoration improves FD. We compared actively and passively restored sites with degraded and reference sites with respect to four key measures of FD (functional richness, evenness, dispersion, and turnover) and two measures of species diversity (richness and evenness). We separately analyzed longitudinal studies (which monitor degraded, reference, and restored sites through time) and space-for-time substitutions (which compare at one point in time degraded and reference sites with restored sites of different ages). Space-for-time studies suggested that species diversity and FD improved over time. However, replicated longitudinal data showed no sustained benefits of active or passive restoration for FD measures, relative to degraded sites. This could suggest that the positive results in space-for-time designs may have been unreliable, but the relatively short duration of longitudinal studies suggests a need for longer-term longitudinal research to robustly demonstrate the absence of any effect. These differences across study designs may explain the variable results found in recent studies directly measuring the response of FD to restoration. We recommend that future assessments of ecological community dynamics include control sites in monitoring, to ensure that the consequences of treatments, including but not limited to restoration, are correctly partitioned from unassisted temporal changes.

Measuring the Efficiency of Alternative Biodiversity Monitoring Sampling Strategies

Monitoring is a crucial tool for measuring the progress and success of environmental policies and management programs. While many studies have evaluated the effectiveness of biodiversity sampling methods, few have compared their efficiency, which is crucial given the funding constraints present in all conservation efforts. In this study we demonstrate how existing analytical tools can be applied to (i) assess the relationship between sampling effort and resulting confidence in biodiversity metrics, and (ii) compare the efficiency of different methods for monitoring biodiversity. We tested this methodology on data from marine fish surveys, including: roving surveys within permanent areas, randomly placed belt transects, and randomly placed transects conducted by citizen scientists using a reduced species list. We constructed efficiency curves describing how increasing effort spent on each method reduced uncertainty in biodiversity estimates and the associated ability to detect change in diversity. All programs produced comparable measurements of species diversity for all metrics despite substantial differences in the species being surveyed by each method. The uncertainty of diversity estimations fell faster and reached a lower level for the roving diver method. Strikingly, the transect method conducted by citizen scientists performed almost identically to the more taxonomically resolved transect method conducted by professional scientists, suggesting that sampling strategies that recorded only a subset of species could still be effective, as long as the excluded species were chosen strategically. The methodology described here can guide decisions about how to measure biodiversity and optimize the resources available for monitoring, ultimately improving management outcomes.

Diversity of Agroforestry Species and Uses in Two Ecological Regions: A Case from Central Nepal

Multiple benefits of the agroforestry systems attract the attention of the global community and are being practiced in Nepal from time immemorial. However, there is minimal evidence of the diversity of species and the use value of plants and their comparative analysis in ecological regions. This study compares the diversity and use value of plants grown in the agroforestry system (home garden) in two separate ecological regions in central Nepal. The frequently used diversity indices were used to measure species diversity. A total of 130 and 99 species, 96 and 69 genera, and 50 and 40 families were reported from home gardens in the Terai and midhill ecological regions, respectively, where 58 species were common for both. The findings reveal Terai farmer prefers ornamental plants over fruit and fodder in the midhills indicating that horticulture and livestock-based livelihood could be enhanced in the hilly region. The diversity indices indicate a higher diversity of plants in the Terai region than in midhills. However, Mann–Whitney U test showed an insignificant difference in species diversity between the regions. Moreover, the chi-square test revealed that there is no significant variation in the use diversity for the regions. The results demonstrate similar plant diversity in the home garden despite the difference in ecological regions and species varieties. The finding assists in understanding the composition of biodiversity in agroforestry systems in specific areas of two different ecological zones and provides insight into the agroforestry for species preferences and use-related decisions. Future research with established management procedures may be required to confirm these findings and provide agroforestry establishment criteria for agricultural sustainability.