Diversity Dynamics Research Articles

Structure in Deep Reinforcement Learning: A Survey and Open Problems

Reinforcement Learning (RL), bolstered by the expressive capabilities of Deep Neural Networks (DNNs) for function approximation, has demonstrated considerable success in numerous applications. However, its practicality in addressing various real-world scenarios, characterized by diverse and unpredictable dynamics, noisy signals, and large state and action spaces, remains limited. This limitation stems from poor data efficiency, limited generalization capabilities, a lack of safety guarantees, and the absence of interpretability, among other factors. To overcome these challenges and improve performance across thesecrucial metrics, one promising avenue is to incorporate additional structural information about the problem into the RL learning process. Various sub-fields of RL have proposed methods for incorporating such inductive biases. We amalgamate these diverse methodologies under a unified framework, shedding light on the role of structure in the learning problem, and classify these methods into distinct patterns of incorporating structure. By leveraging this comprehensive framework, we provide valuable insights into the challenges of structured RL and lay the groundwork for a design pattern perspective on RL research. This novelperspective paves the way for future advancements and aids in developing more effective and efficient RL algorithms that can potentially handle real-world scenarios better.

Comparative analysis of diversification-marketing challenges faced by farmers in North India

This study delves into the dynamics of crop diversification, offers a comparative analysis, and explores the marketing challenges confronting farmers in northern India. Crop diversification has gained prominence as a sustainable agricultural practice necessitated by ecological concerns and market fluctuations. Drawing from a wide array of secondary sources, including government reports, academic literature, and agricultural data, this research investigates the evolution of crop diversification in different regions. We scrutinize the diversification trends in North India, highlighting the shifts in crop choices such as rice, wheat, pulses, and cash crops. In parallel, we address the multifaceted marketing challenges faced by farmers across these regions. This includes the influence of intermediaries, price volatility, logistical constraints, and quality compliance issues. We explore the varying impacts of government policies and schemes in alleviating these challenges. Furthermore, the research reveals that effective marketing solutions are pivotal for guaranteeing equitable returns for farmers diversifying their crops. The role of government interventions emerges as a critical factor in this context.

Revealing hidden diversity and community dynamics of land snails through DNA barcoding: implications for conservation and ecological studies

IntroductionLand snails play a crucial role in maintaining ecosystem sustainability within their habitats. Therefore, understanding the characteristics of their communities is vital for ecological studies and the development of effective conservation strategies. In this study, land snail communities inhabiting the Hyrcanian forest were identified and the variations in their community composition along elevational gradients were investigated.MethodsSnail samples were collected from three distinct elevations in three different forest locations within the Hyrcanian area of Iran. This study utilized DNA barcoding to identify land snail species. By employing statistical analyses such as ANOVA and PERMANOVA, significant differences in the features of snail communities across different elevations were examined. Concurrently, soil samples were collected from each site to assess soil physicochemical parameters about snail presence.ResultThrough this comprehensive analysis, a total of 10 OTUs, were further classified into seven families, and nine genera were identified. Five of these genera had never been reported in the study region before. We observed a decline in OTU richness with increasing elevation; however, the maximum abundance of snails was found at higher elevations. CCA demonstrated that Ca, Mg, and moisture saturation predominantly shape snail community composition.DiscussionThe unique climatic conditions and spatial distribution of precipitation from lowlands to highlands, as well as from west to east, make the Hyrcanian forests an ideal case study area for understanding the dynamics of land snail communities. In summary, this study provides new insights into the land snail communities thriving in the Hyrcanian forests. The findings from our research can contribute to the development of effective conservation management strategies for forest ecosystems. By understanding the factors influencing the distribution and composition of land snail communities, we can make informed decisions to protect and preserve land snails and the balance they maintain within their habitats.

Exploring fish communities in the mud volcano polluted river using environmental DNA metabarcoding

In ecosystems subjected to environmental disturbances such as mud volcanoes, understanding the dynamics of fish communities is essential for ecological assessment and conservation. This study employs environmental DNA (eDNA) metabarcoding for the first time to explore fish communities within a challenging and unique environment—a mud volcano-polluted river. High-throughput sequencing was utilized to assess alpha and beta diversity, revealing distinct patterns in fish community composition in response to mud discharge activity. The results indicate that affected sites exhibit remarkably different communities during active and inactive mud discharge, with the impact extending downstream to the river mouth. Notably, the application of eDNA metabarcoding identified a vulnerable species, Rasbora lateristriata, emphasizing its utility in detecting high-risk species. Despite challenges in species identification and reference databases, the use of longer 16S rRNA fragments offered enhanced taxonomic resolution and interspecific sequence variation. This approach showcases the potential of eDNA metabarcoding in assessing fish diversity and community dynamics in polluted aquatic ecosystems, emphasizing its significance in biodiversity surveys and ecological monitoring. The study underscores the value of eDNA metabarcoding as an efficient and comprehensive tool for studying freshwater ecosystems and highlights the need for expanding reference databases to address genetic coverage gaps, particularly in less-studied environments.

Group-Based Interventions in Lifestyle Medicine.

Group-based interventions in health care have demonstrated a positive influence on patient outcomes by strengthening patient-healthcare professional relationships and providing an avenue for patient empowerment through shared experiences and belongingness. Groups have been shown to enhance social and psychological support, improve self-management behaviors, and encourage peer-support. However group settings also present challenges, such as discomforts in sharing within a group context and managing diverse group dynamics. We outline the efficacy and dynamics of group-based activities in health care settings. This includes key behavioral components of groups, such as creating a safe, supportive, and cohesive environment in group activities where confidentiality is paramount. By recognizing principles for group and moderator behaviors, individuals are more likely to maximize the potential of these interventions.

“We don’t separate out these things. Everything is related”: Partnerships with Indigenous Communities to Design, Implement, and Evaluate Multilevel Interventions to Reduce Health Disparities

Multilevel interventions (MLIs) are appropriate to reduce health disparities among Indigenous peoples because of their ability to address these communities’ diverse histories, dynamics, cultures, politics, and environments. Intervention science has highlighted the importance of context-sensitive MLIs in Indigenous communities that can prioritize Indigenous and local knowledge systems and emphasize the collective versus the individual. This paradigm shift away from individual-level focus interventions to community-level focus interventions underscores the need for community engagement and diverse partnerships in MLI design, implementation, and evaluation. In this paper, we discuss three case studies addressing how Indigenous partners collaborated with researchers in each stage of the design, implementation, and evaluation of MLIs to reduce health disparities impacting their communities. We highlight the following: (1) collaborations with multiple, diverse tribal partners to carry out MLIs which require iterative, consistent conversations over time; (2) inclusion of qualitative and Indigenous research methods in MLIs as a way to honor Indigenous and local knowledge systems as well as a way to understand a health disparity phenomenon in a community; and (3) relationship building, maintenance, and mutual respect among MLI partners to reconcile past research abuses, prevent extractive research practices, decolonize research processes, and generate co-created knowledge between Indigenous and academic communities.

The mussel larvae microbiome changes in response to a temperature rise

Ocean warming caused by global climate change influences the function, diversity, and community dynamics of commensal microorganisms, including the hemolymph and the gut microbiota in mussels. However, the microbiota in hard-shelled mussel (Mytilus coruscus) larvae and the effect of temperature on the microbial community structure have yet to be studied. Herein, we investigated the core microbiota of M. coruscus larvae and the impact of acute (4 h) and gradual (4 days) exposure to a rise in seawater temperature from 21 to 25 °C. Eleven core genera were identified in M. coruscus larvae by 16S rDNA gene sequencing: Alteromonas, Brevundimonas, Delftia, Microbacterium, Neptuniibacter, Neptunomonas, Pseudoalteromonas, Rhodococcus, Stenotrophomonas, Tenacibaculum, and Thalassotalea. The microbiota of larvae in the short exposure treatment was similar to the control. However, the abundance of Delftia, Neptunomonas, Pseudoalteromonadaceae, Rhodococcus, and Stenotrophomonas decreased significantly in the long-exposure larvae. In contrast, at the genus level, the abundance of Tenacibaculum increased significantly. Diversity and multivariate analyses confirmed that the microbiota patterns were linked to seawater warming over the long term. Microbiota diversity did not change significantly, regardless of whether the seawater temperature increased quickly or slowly; however, we observed a significant increase in the microbiota species abundance at higher temperatures. Among the altered bacterial genera, Delftia, Neptunomonas, and Rhodococcus function in the degradation of organic compounds; Pseudoalteromonas is closely associated with mussel attachment and metamorphosis, and Tenacibaculum is an opportunistic pathogen that can cause marine mollusk death. The results suggest that marine heat waves caused by climate change may reduce the ability of symbiotic bacteria to degrade environmental toxins, will affect mussel larvae metamorphosis, and increase the abundance of opportunistic pathogens, thereby increasing the risk of disease and death of mussel larvae.

Participatory ecodesign of crop management based on Life Cycle Assessment: an approach to inform the strategy of a Protected Denomination of Origin. A case study in viticulture

Since the context on environmental issues is challenging, the Cognac protected denomination of origin (PDO) adopted life cycle assessment (LCA) to inform its environmental strategy, initially focusing on vineyard soil management. This study developed a participatory eco-design approach involving stakeholders to inform the PDOs’ strategy for transitioning to less impactful crop management practices. It did this by drawing on literature that emphasises the use of participatory design, serious games, and LCA to foster knowledge sharing, engagement, and sustainability assessment. The approach that was put to the test in the Cognac PDO involved 17 elected officials with varying levels of experience. The participants used the serious game known as Vitigame (a game done for participatory ecodesign in viticulture) to ecodesign a soil management and fertilisation pathway for 2030, with the process guided by the results of the LCA. Exchange dynamics, LCA results, and participant feedback were analysed. The study revealed diverse dynamics and efficient ecodesign strategies among the participant groups, which resulted in a reduction of environmental impacts by up to 51% and raised new questions for the territory. The diversity of participants presented challenges, highlighting the need to improve LCA knowledge sharing. The workshop’s results could inform the PDO’s strategic planning. The interest of this innovative process including a serious game was confirmed, suggesting potential applications to other viticultural PDOs and adaptability to diverse sectors.

Species identification and spatial diversity patterns of the Giant Panda National Park (GPNP) in Ya’an, Sichuan, China

National parks play a crucial role in global biodiversity preservation, with China’s Giant Panda National Park (GPNP) serving as a key stronghold for protecting unique flora and fauna endemic to diverse mountainous regions. This study focused on unraveling the dynamics of diversity within local giant panda populations and their sympatric species in the Ya’an section of the GPNP. Five specific local population patches (LPPs) were selected as subjects, utilizing data from the 4th National Giant Panda Survey. Through identification, classification, and analysis of observed species within each LPP, α and β diversity patterns were revealed, leading to actionable recommendations. A comprehensive record of 34 species spanning 5 orders and 16 families was documented. Notably, 8 species were under the first-class of the National Key Protected Wildlife List in China, and the IUCN Red List has identified 3 species – Rhinopithecus roxellana, Moschus berezovskii, and Ailurus styani – as endangered, showing its high biodiversity and conservation significance. While α-diversity assessment highlighted the DaxianglingA2 (DXLA2) with the highest Shannon-Wiener and Simpson’s indices, the QionglaishanA3 (QLSA3) exhibited greater species richness. However, these differences lacked statistical significance (P > 0.05). The Jaccard similarity coefficient indicated a stronger turnover process compared to nestedness. The dominance of turnover in total β-diversity accentuated the importance of encompassing all five LPPs in conservation strategies. The study underscored the imperative of conservation management for each LPP, with a focus on enhancing habitat connectivity between disparate small LPPs to prevent species extinction by fostering species exchange and gene flow. This pioneering research shed light on spatial utilization patterns and diversity drivers for local giant panda populations and their sympatric species within the GPNP. It provides valuable references to appraise conservation strategy effectiveness and offers scientific backing to optimize biodiversity conservation and management within national parks and protected areas.

Exploring optical soliton solutions in highly dispersive couplers with parabolic law nonlinear refractive index using the extended auxiliary equation method

This study delves into the realm of optical soliton solutions within the intricate framework of highly dispersive couplers integrated with optical metamaterials featuring a parabolic law nonlinear refractive index. Employing the extended auxiliary equation method, the investigation systematically unveils various soliton solutions, including dark solitons, bright solitons, singular solitons, and a distinctive amalgamation of bright and singular solitons. The results illuminate the diverse dynamics of solitons in these complex systems, offering crucial insights into the interplay among dispersion, nonlinearity, and metamaterial characteristics. Beyond enhancing the theoretical understanding of soliton behavior in optical metamaterial couplers, the findings hold practical significance by potentially influencing the design and optimization of optical communication devices and systems.

Unraveling the Complex Dynamics of Soil Microbiome Diversity and Its Implications for Ecosystem Functioning: A Comprehensive Review

Soil microbiome diversity plays a pivotal role in shaping terrestrial ecosystems and the myriad functions. This comprehensive review delves into the intricate dynamics of soil microbial communities, exploring their composition, interactions, and responses to environmental factors. By synthesizing findings from cutting-edge research, we aim to elucidate the complex interplay between soil microbiome diversity and ecosystem functioning. We discuss the application of advanced techniques, such as high-throughput sequencing and metagenomic analysis, which have revolutionized our understanding of soil microbial diversity. The review highlights the influence of biotic and abiotic factors, including plant diversity, soil properties, climate, and land-use practices, on the structure and diversity of soil microbial communities. We examine the mechanisms through which soil microbes drive critical ecosystem processes, such as nutrient cycling, carbon sequestration, and plant productivity. The review also explores the resilience and adaptability of soil microbial communities in the face of global change pressures, such as climate change, land-use intensification, and biodiversity loss. We discuss the potential implications of altered soil microbiome diversity for ecosystem functioning and the provision of essential ecosystem services. Furthermore, we identify knowledge gaps and propose future research directions to advance our understanding of soil microbiome diversity and its role in maintaining healthy and productive ecosystems. This review provides a comprehensive framework for understanding the complex dynamics of soil microbiome diversity and underscores its critical importance in shaping the functioning and sustainability of terrestrial ecosystems in a changing world.

Prophage maintenance is determined by environment-dependent selective sweeps rather than mutational availability

Prophages, viral sequences integrated into bacterial genomes, can be beneficial and costly. Despite the risk of prophage activation and subsequent bacterial death, active prophages are present in most bacterial genomes. However, our understanding of the selective forces that maintain prophages in bacterial populations is limited. Combining experimental evolution with stochastic modeling, we show that prophage maintenance and loss are primarily determined by environmental conditions that alter the net fitness effect of a prophage on its bacterial host. When prophages are too costly, they are rapidly lost through environment-specific sequences of selective sweeps. Conflicting selection pressures that select against the prophage but for a prophage-encoded accessory gene can maintain prophages. The dynamics of prophage maintenance additionally depend on the sociality of this accessory gene. Prophage-encoded genes that exclusively benefit the lysogen maintain prophages at higher frequencies compared with genes that benefit the entire population. That is because the latter can protect phage-free "cheaters," reducing the benefit of maintaining the prophage. Our simulations suggest that environmental variation plays a larger role than mutation rates in determining prophage maintenance. These findings highlight the complexity of selection pressures that act on mobile genetic elements and challenge our understanding of the role of environmental factors relative to random chance events in shaping the evolutionary trajectory of bacterial populations. By shedding light on the key factors that shape microbial populations in the face of environmental changes, our study significantly advances our understanding of the complex dynamics of microbial evolution and diversification.

Effects of lianas on forest biogeochemistry during their lives and afterlives.

Climate change and other anthropogenic disturbances are increasing liana abundance and biomass in many tropical and subtropical forests. While the effects of living lianas on species diversity, ecosystem carbon, and nutrient dynamics are receiving increasing attention, the role of dead lianas in forest ecosystems has been little studied and is poorly understood. Trees and lianas coexist as the major woody components of forests worldwide, but they have very different ecological strategies, with lianas relying on trees for mechanical support. Consequently, trees and lianas have evolved highly divergent stem, leaf, and root traits. Here we show that this trait divergence is likely to persist after death, into the afterlives of these organs, leading to divergent effects on forest biogeochemistry. We introduce a conceptual framework combining horizontal, vertical, and time dimensions for the effects of liana proliferation and liana tissue decomposition on ecosystem carbon and nutrient cycling. We propose a series of empirical studies comparing traits between lianas and trees to answer questions concerning the influence of trait afterlives on the decomposability of liana and tree organs. Such studies will increase our understanding of the contribution of lianas to terrestrial biogeochemical cycling, and help predict the effects of their increasing abundance.

Viral Metatranscriptomic Analysis to Reveal the Diversity of Viruses Infecting Satsuma Mandarin (Citrus unshiu) in Korea.

Citrus cultivation plays a pivotal role, making a significant contribution to global fruit production and dietary consumption. Accurate identification of viral pathogens is imperative for the effective management of plant viral disease in citrus crops. High-throughput sequencing serves as an alternative approach, enabling comprehensive pathogen identification on a large scale without requiring pre-existing information. In this study, we employed HTS to investigate viral pathogens infecting citrus in three different regions of South Korea: Jejudo (Jeju), Wando-gun (Wando), and Dangjin-si (Dangjin). The results unveiled diverse viruses and viroids that exhibited regional variations. Notably, alongside the identification of well-known citrus viruses such as satsuma dwarf virus, citrus tatter leaf virus, and citrus leaf blotch virus (CLBV), this study also uncovered several viruses and viroids previously unreported in Korean citrus. Phylogenetic analysis revealed that majority of identified viruses exhibited the closest affilations with isolates from China or Japan. However, CLBV and citrus viroid-I-LSS displayed diverse phylogenetic positions, reflecting their regional origins. This study advances our understanding of citrus virome diversity and regional dynamics through HTS, emphasizing its potential in unraveling intricate viral pathogens in agriculture. Consequently, it significantly contributes to disease management strategies, ensuring the resilience of the citrus industry.

Influences of coriolis force and friction on fluid dynamics in specific paraboloid basins

Natural water features, such as rivers, lakes, bays, and straits, exhibit diverse shapes and dynamics. Among these, paraboloid basins, resembling the contours of lakes or closed bays, offer a relatively simple yet intriguing case. This study delves into the dynamics of water waves within two distinct paraboloid basin variations: the parabolic canal and the circular paraboloid. In this investigation, we analyze shoreline movement, considering influential factors such as bottom friction and the Coriolis effect through a mathematical model. The foundation of our analysis lies in the two-dimensional shallow water equations, with the Thacker assumption serving as the basis for deriving an analytical solution. To enhance our understanding, we employ a numerical solution, employing the finite volume method on a staggered grid, to simulate wave behavior within these basin variations. For validation, we compare these numerical findings with our analytical solution. Furthermore, this study conducts a sensitivity analysis of the Coriolis parameter and bottom friction parameter under various conditions. Through this exploration, we gain valuable insights into the interplay of these critical factors in shaping the oscillation of water within paraboloid basins, enriching our understanding of coastal and basin dynamics.

Dynamics of Diversity of Spined Loaches of Genus Cobitis (Cobitidae) of Trans-Caucasus in the Anthropogenic Period According to the Data of Museum Collections. III. Morpho-genetic Variability, Taxonomic Status and Diagnostic Characters of Spined Loaches of the Black Sea Coast North of the Meskheti Ridge of the Lesser Caucasus

Dynamics of Diversity of Spined Loaches of Genus Cobitis (Cobitidae) of Trans-Caucasus in the Anthropogenic Period According to the Data of Museum Collections. III. Morpho-genetic Variability, Taxonomic Status and Diagnostic Characters of Spined Loaches of the Black Sea Coast North of the Meskheti Ridge of the Lesser Caucasus

BioLuminescent OptoGenetics in the choroid plexus: integrated opto- and chemogenetic control in vivo.

The choroid plexus (ChP) epithelial network displays diverse dynamics, including propagating calcium waves and individuated fluctuations in single cells. These rapid events underscore the possibility that ChP dynamics may reflect behaviorally relevant and clinically important changes in information processing and signaling. Optogenetic and chemogenetic tools provide spatiotemporally precise and sustained approaches for testing such dynamics in vivo. Here, we describe the feasibility of a novel combined opto- and chemogenetic tool, BioLuminescent-OptoGenetics (BL-OG), for the ChP in vivo. In the "LuMinOpsin" (LMO) BL-OG strategy, a luciferase is tethered to an adjacent optogenetic element. This molecule allows chemogenetic activation when the opsin is driven by light produced through luciferase binding a small molecule (luciferin) or by conventional optogenetic light sources and BL-OG report of activation through light production. To test the viability of BL-OG/LMO for ChP control. Using transgenic and Cre-directed targeting to the ChP, we expressed LMO3 (a Gaussia luciferase-VChR1 fusion), a highly effective construct in neural systems. In mice expressing LMO3 in ChP, we directly imaged BL light production following multiple routes of coelenterazine (CTZ: luciferin) administration using an implanted cannula system. We also used home-cage videography with Deep LabCut analysis to test for any impact of repeated CTZ administration on basic health and behavioral indices. Multiple routes of CTZ administration drove BL photon production, including intracerebroventricular, intravenous, and intraperitoneal injection. Intravenous administration resulted in fast "flash" kinetics that diminished in seconds to minutes, and intraperitoneal administration resulted in slow rising activity that sustained hours. Mice showed no consistent impact of 1 week of intraperitoneal CTZ administration on weight, drinking, motor behavior, or sleep/wake cycles. BL-OG/LMO provides unique advantages for testing the role of ChP dynamics in biological processes.

The Sequential Direct and Indirect Effects of Mountain Uplift, Climatic Niche, and Floral Trait Evolution on Diversification Dynamics in an Andean Plant Clade.

Why and how organismal lineages radiate is commonly studied through either assessing abiotic factors (biogeography, geomorphological processes, and climate) or biotic factors (traits and interactions). Despite increasing awareness that both abiotic and biotic processes may have important joint effects on diversification dynamics, few attempts have been made to quantify the relative importance and timing of these factors, and their potentially interlinked direct and indirect effects, on lineage diversification. We here combine assessments of historical biogeography, geomorphology, climatic niche, vegetative, and floral trait evolution to test whether these factors jointly, or in isolation, explain diversification dynamics of a Neotropical plant clade (Merianieae, Melastomataceae). After estimating ancestral areas and the changes in niche and trait disparity over time, we employ Phylogenetic Path Analyses as a synthesis tool to test eleven hypotheses on the individual direct and indirect effects of these factors on diversification rates. We find strongest support for interlinked effects of colonization of the uplifting Andes during the mid-Miocene and rapid abiotic climatic niche evolution in explaining a burst in diversification rate in Merianieae. Within Andean habitats, later increases in floral disparity allowed for the exploitation of wider pollination niches (i.e., shifts from bee to vertebrate pollinators), but did not affect diversification rates. Our approach of including both vegetative and floral trait evolution, rare in assessments of plant diversification in general, highlights that the evolution of woody habit and larger flowers preceded the colonization of the Andes, but was likely critical in enabling the rapid radiation in montane environments. Overall, and in concert with the idea that ecological opportunity is a key element of evolutionary radiations, our results suggest that a combination of rapid niche evolution and trait shifts was critical for the exploitation of newly available niche space in the Andes in the mid-Miocene. Further, our results emphasize the importance of incorporating both abiotic and biotic factors into the same analytical framework if we aim to quantify the relative and interlinked effects of these processes on diversification.

From problem to progress: Rodent management in agricultural settings of sub-Saharan Africa and calling for an urban perspective

In sub-Saharan Africa, agricultural intensification and urbanization have increased the risk of proliferation of rodents in rural and urban habitats. Management of rodent populations is a challenge in terms of food security and public health. However, conventional efforts to manage rodents are currently reactive and based on the inadequate use of synthetic chemical rodenticides, including first- and second-generation anticoagulants and acute rodenticides. This approach carries substantial environmental and health risks and has yielded limited success in terms of reduction of rodent populations sustainably. In this paper, which is the second part of a diptych, we advocate for a shift towards more sustainable and environmentally friendly approaches, such as Ecologically-Based Rodent Management (EBRM), as a realistic alternative to synthetic rodenticides. This method is based on a good knowledge of habitat use, species diversity and population dynamics of major rodent pests, and involves community-based interventions aimed at reducing rodent abundance to economically and hygienically acceptable levels in the long term. We present for the first time a comprehensive compilation of published and unpublished information derived from observational field studies conducted in Ethiopia, Niger, Nigeria, Benin, Mali, Mauritania and Senegal with the aim to provide an overview of EBRM case studies in these countries of sub-Saharan Africa. This paper intends to serve as a catalyst for change, encouraging the transformation of rodent management practices towards sustainable methods. We aim at stimulating further research and interventions that promote EBRM in Africa, ultimately fostering more environmentally conscious and effective solutions.

Monitoring the Diversity of Lizards and Snakes (Reptilia: Squamata), Along the Boyong-Code River Area, Province of Daerah Istimewa Yogyakarta

A reptile is a group of animal consists of testudines, crocodiles, lizards, and snakes. Most reptiles are capable of occupying wide range of habitats with different environmental conditions. One of the preferred habitats for reptiles is a river. Boyong-Code River is one of the rivers that flow across the Province of Daerah Istimewa Yogyakarta (DIY). Research on the diversity of lizards and snakes in the Boyong-Code River has been done in 2012. This research aims to acquire new data on the diversity of herpetofauna in the Boyong-Code River and compare it with 2012 data research. The comparison purpose is to monitor the species diversity dynamics after 5 years. The data of herpetofauna diversity were acquired using a combination of several methods, i.e., VES (Visual Encounter Survey), riverbank cruising, and transect. Sampling areas in 2012 and 2017 were divided into three locations, i.e., upstream, midstream, and downstream. Species diversity of lizards and snakes in the Boyong-Code River in 2017 consists of eight species of lizards (lacertilians: squamates: reptiles) and four species of snakes (serpents: squamates: reptiles). Species diversity dynamics were equal for lizards in 2012 and 2017; meanwhile, there were more species of snakes in 2012 compared to 2017.
 Keywords: monitoring, diversity, lizards, snakes, reptiles, squamates, boyong-code river, Daerah Istimewa Yogyakarta