Sachit Rajbhandari

Mr. Sachit Rajbhandari

orcid

Research Focus & Metrics

Academic Career Length

20Years (2007-Present)

(Calculated once Scilit publication data is synced: current year − year of first publication + 1)

Representative Publications

View All Publications
1 May 2025 in Environmental DNA
Verified
Journal Article
Open access
MTMiwa Takahashi
Miwa Takahashi
TFTobias Guldberg Frøslev
Tobias Guldberg Frøslev
JPJoana Paupério
Joana Paupério
BTBettina Thalinger
Bettina Thalinger
KKKaty Klymus
Katy Klymus
OBOliver Berry
Oliver Berry
The success of environmental DNA (eDNA) approaches for species detection has revolutionized biodiversity monitoring and distribution mapping. Targeted eDNA amplification approaches, such as quantitative PCR, have improved our understanding of species distribution, and metabarcoding‐based approaches have enabled biodiversity assessment at unprecedented scales and taxonomic resolution. eDNA datasets, however, are often scattered across repositories with inconsistent formats, varying access restrictions, and inadequate metadata; this limits their interoperation, reuse, and overall impact. Adopting FAIR (Findable, Accessible, Interoperable, and Reusable) data practices with eDNA data can transform the monitoring of biodiversity and individual species and support data‐driven biodiversity management across broad scales. FAIR practices remain underdeveloped in the eDNA community, partly due to gaps in adapting existing vocabularies, such as Darwin Core (DwC) and Minimum Information about any (x) Sequence (MIxS), to eDNA‐specific needs and workflows. To address these challenges, we propose a comprehensive FAIR eDNA (FAIRe) Metadata Checklist, which integrates existing data standards and introduces new terms tailored to eDNA workflows. Metadata are systematically linked to both raw data (e.g., metabarcoding sequences, Ct/Cq values of targeted qPCR assays) and derived biological observations (e.g., Amplicon Sequence Variant (ASV)/Operational Taxonomic Unit (OTU) tables, species presence/absence). Along with formatting guidelines, tools, templates, and example datasets, we introduce a standardized, ready‐to‐use approach for FAIR eDNA practices. Through broad collaboration, we seek to integrate these guidelines into established biodiversity and molecular data standards, promote journal data policies, and foster user‐driven improvements and uptake of FAIR practices among eDNA data producers. In proposing this standardized approach and developing a long‐term plan with key databases and data standard organizations, the goal is to enhance accessibility, maximize reuse, and elevate the scientific impact of these valuable biodiversity data resources.

1 May 2012 in Journal of Integrative Agriculture
Verified
Journal Article
Open access
SRSachit Rajbhandari
Sachit Rajbhandari
JKJohannes Keizer
Johannes Keizer

1 January 2012 in International Journal of Metadata, Semantics and Ontologies
Verified
Journal Article
Open access
CCCaterina Caracciolo
Caterina Caracciolo
ASArmando Stellato
Armando Stellato
SRSachit Rajbhandari
Sachit Rajbhandari
AMAhsan Morshed
Ahsan Morshed
GJGudrun Johannsen
Gudrun Johannsen
YJYves Jaques
Yves Jaques
The AGROVOC multilingual thesaurus maintained by the Food and Agriculture Organisation (FAO) of the United Nations is now published as linked data. In order to reach this goal AGROVOC was expressed in Simple Knowledge Organisation System (SKOS) and its concepts provided with dereferenceable URIs. AGROVOC is now aligned with ten other multilingual Knowledge Organisation Systems (KOS) related to agriculture, using the SKOS properties exact match and close match. Alignments were automatically produced in Eclipse using a custom-designed tool and then validated by a domain expert. The resulting data is publicly available to both humans and machines using a SPARQL endpoint together with a modified version of Pubby, a lightweight front-end tool for publishing linked data. This paper describes the process that led to the current linked data AGROVOC and discusses current and future applications and directions. This paper extends a shorter version presented at MTSR 2011.

21 May 2015
Verified
Book Chapter
Closed access
PDF file
ASArmando Stellato
Armando Stellato
SRSachit Rajbhandari
Sachit Rajbhandari
ATAndrea Turbati
Andrea Turbati
MFManuel Fiorelli
Manuel Fiorelli
CCCaterina Caracciolo
Caterina Caracciolo
MPMaria Teresa Pazienza
Maria Teresa Pazienza

1 March 2019 in Remote Sensing
Verified
Journal Article
Open access
PDF file
SRSachit Rajbhandari
Sachit Rajbhandari
Jagannath AryalJagannath Aryal
Jagannath Aryal
JOJonathan Osborn
Jonathan Osborn
ALArko Lucieer
Arko Lucieer
RMRobert Musk
Robert Musk
Ontology-driven Geographic Object-Based Image Analysis (O-GEOBIA) contributes to the identification of meaningful objects. In fusing data from multiple sensors, the number of feature variables is increased and object identification becomes a challenging task. We propose a methodological contribution that extends feature variable characterisation. This method is illustrated with a case study in forest-type mapping in Tasmania, Australia. Satellite images, airborne LiDAR (Light Detection and Ranging) and expert photo-interpretation data are fused for feature extraction and classification. Two machine learning algorithms, Random Forest and Boruta, are used to identify important and relevant feature variables. A variogram is used to describe textural and spatial features. Different variogram features are used as input for rule-based classifications. The rule-based classifications employ (i) spectral features, (ii) vegetation indices, (iii) LiDAR, and (iv) variogram features, and resulted in overall classification accuracies of 77.06%, 78.90%, 73.39% and 77.06% respectively. Following data fusion, the use of combined feature variables resulted in a higher classification accuracy (81.65%). Using relevant features extracted from the Boruta algorithm, the classification accuracy is further improved (82.57%). The results demonstrate that the use of relevant variogram features together with spectral and LiDAR features resulted in improved classification accuracy.

Verified
Journal Article
Open access
PDF file
SRSachit Rajbhandari
Sachit Rajbhandari
Jagannath AryalJagannath Aryal
Jagannath Aryal
JOJonathan Osborn
Jonathan Osborn
RMRob Musk
Rob Musk
ALArko Lucieer
Arko Lucieer
In Geographic Object-based Image Analysis (GEOBIA), identification of image objects is normally achieved using rule-based classification techniques supported by appropriate domain knowledge. However, GEOBIA currently lacks a systematic method to formalise the domain knowledge required for image object identification. Ontology provides a representation vocabulary for characterising domain-specific classes. This study proposes an ontological framework that conceptualises domain knowledge in order to support the application of rule-based classifications. The proposed ontological framework is tested with a landslide case study. The Web Ontology Language (OWL) is used to construct an ontology in the landslide domain. The segmented image objects with extracted features are incorporated into the ontology as instances. The classification rules are written in Semantic Web Rule Language (SWRL) and executed using a semantic reasoner to assign instances to appropriate landslide classes. Machine learning techniques are used to predict new threshold values for feature attributes in the rules. Our framework is compared with published work on landslide detection where ontology was not used for the image classification. Our results demonstrate that a classification derived from the ontological framework accords with non-ontological methods. This study benchmarks the ontological method providing an alternative approach for image classification in the case study of landslides.