Taxonomic Diversity of Carabid Beetles in the Agricultural Landscape under Hot Semi-Arid Climate in Mandi Bahauddin, Punjab, Pakistan

Ground beetles are recognized as important biological control agents and environmental indicators that inhabit a wide range of habitats. The diversity of carabid beetles in Pakistan has not yet been studied extensively, despite their diversified ecological roles. In the present study, the ground beetle communities from three subdivisions of district Mandi Bahauddin (Phalia, Malakwal and Mandi Bahauddin) were sampled by handpicking and placing pitfall traps from August 2020 to July 2021. A total of 4008 specimens were collected which belonged to 18 species, 11 genera, nine tribes, and five subfamilies. Data were analyzed with Similarities Percentage (SIMPER) analysis and diversity indices were compared among those three croplands. We found that Pheropsophus lissoderus was the most abundant and dominant species in all three study sites whereas Brachinus bilineatus and Galerita lecontei were recorded only in tehsil Phalia, Pheropsophus verticalis, and Dioryche subrecta in Malakwal. Pheropsophus was the most abundant and dominant genus representing six species in all three sites. Overall Shannon index (H:2.545), Simpson index (1-D:0.893), and evenness (e ˄ H/S: 0.709) indicated relatively greater carabid species richness in district Mandi Bahauddin. Comparative values of indices showed similar patterns of species diversity and evenness i.e. Mandi Bahauddin (1-D = 0.902, e ˄ H/S = 0.866), followed by Malakwal (1-D = 893, e ˄ H/S = 0.769), and Phalia (1-D = 0.876, e ˄ H/S = 0.712). Similarity Percentage analysis by using the Bray-Curtiss dissimilarity matrix showed the highest overall dissimilarity between Malakwal and Mandi Bahauddin (42.68%), followed by Phalia, and Malakwal (28.88%), whereas the least dissimilarity was recorded between Phalia and Mandi Bahauddin (26.53%). We conclude that carabid beetles in district Mandi Bahauddin have relatively greater species richness. The study reports Poecilus versicolor for the first time from Pakistan.


INTRODUCTION
T he ground beetles (Carabidae: Coleoptera) also called carabid beetles represent approximately 40,000 described species (Riddick and Capinera, 2008) that inhabit almost all terrestrial habitats, especially in agroecosystems (Della Rocca et al., 2021). Carabid beetles consume several agricultural pests and weeds (De Heij and Willenborg, 2020), and their diversity in agroecosystems is mainly related to the microclimate rather than crop type (Reich et al., 2020). Ground beetles are key species in agricultural landscapes contributing significantly to the ecosystem as natural enemies of many pest species (Piotrowska et al., 2020).
Several beneficial insect species have shown a decline in the population due to agricultural intensification (Forister et al., 2016;Raven and Wagner, 2021;van der Sluijs, 2020;Wepprich et al., 2019). Agricultural intensification (Rusch et al., 2016), climate change (Brandmayr and Pizzolotto, 2016), and habitat fragmentation (Niemelä, 2001) affect carbid diversity. Landscape assessments and consequently re-establishment of semi-natural habitats contribute significantly to detecting and minimizing biodiversity losses, which will be beneficial to agricultural production (Raven and Wagner, 2021;Wang et al., 2021). Extensive works at global, regional and local assessment of carabid beetles assemblages have been made to explore taxonomic diversity in different agroecosystems (Rischen et al., 2021;Rouabah et al., 2015;Zajicek et al., 2021;Zou et al., 2015). The carabid fauna has not been explored from different agricultural zones of Pakistan though some work on diversity were reported from different parts of O n l i n e

F i r s t A r t i c l e
Pakistan (Hussain et al., 2021). Some research work on the distribution and diversity of species was conducted in different parts of the country i.e. carabid fauna segregated from the fauna of British India (Kazi et al., 2016), district Haripur (Bibi and Rehman, 2020), checklist of ground beetles (Azadbakhsh and Rafi, 2017), Mekran Division , Mansehra Division (Mishkatullah, 2018), ecological zones of Sukkur (Soomro et al., 2021), and upper Sindh plains (Sahito et al., 2021). In Mandi Bahauddin, being an agricultural district, baseline data on the carabid diversity has not been explored yet. The composition and density of carabid taxa vary according to environmental conditions like temperature and rainfall, edaphic factors, and the communities. This asserts the assessment of carabid communities at local levels which would be helpful in the analysis of species diversity to evaluate the impact of environment within the habitat concerned. The objective of this study is to explore the community patterns of carabid beetles in the agricultural landscape of district Mandi Bahauddin.

Study area
Mandi Bahauddin (32.4105° N, 73.3709° E; 220 m asl) is located in the province of Punjab, Pakistan. It has three subdivisions (Tehsils) i.e. Mandi Bahauddin, Phalia and Malakwal. The district has predominantly agricultural economy. The district is located between two major rivers Jhelum and Chenab and is commonly known as Chajjdoab. Mostly irrigated through Lower Jhelum Canal and partly through Upper Jhelum Canal. The climate of this district is classified as BSh (hot semi-arid climate) by the Koppen-Geiger system (Ranjha et al., 2018). The climate of the district is moderate, hot during summer, and cold during winter. The highest temperature in summer may rise to 48 °C and may fall below 3 °C in winter. Generally, weather reverberates with Islamabad with an average rainfall of 388 millimeters. Most of the land near this town is arable and residents are involved in agriculture. Wheat (Triticum aestivum), rice (Oryza sativa), sugarcane (Saccharum officinarum), corn (Zea mays) and potato (Solanum tuberosum) are commonly cultivated crops. Wild plants include bhakra (Tribulus terrestris), khabal (Cynodon dactylon), baer (Ziziphus jujuba), pipal (Ficus religiosa), kala toot (Morus nigra), Dherak (Melia azedarach) and chibbar (Cucumis melo var. agrestis) (Nisar et al., 2011).

Collection of specimens
Adult carabid beetles were collected fortnightly from August 2020 to July 2021 by hand picking and pitfall traps. Three transects of 500 m length were placed for data collection. Ten pitfall traps were built at 150 m distance along transects in all locations (Andrade et al., 2011;Larsen and Forsyth, 2005). Plastic flasks were used to prepare the pitfall traps and then burrowed into the soil with their edge leveled with soil surface. Vinegar was used as an attractant in pitfall traps and traps were emptied after 72 h (Steward et al., 2017).

Identification of specimens
The morphological characters of preserved samples were identified under dissecting microscope, using available taxonomic identification keys, pictorial keys and online resources (Abdullah and Azmir, 2021;Choate, 2001;Klimaszewski and Watt, 1997).

Statistical analysis
Species richness measures biodiversity by taking into account the number of species in a given area. Margalef's diversity index and Menhinick's diversity indices report species richness whereas Richness-Evenness indices like Shannon-Wiener diversity index, Brillouin index, Fisher's alpha, Pielou index, and Simpson's index (Hussain et al., 2021;Magurran, 2004). We calculated ecological indicator these indices for measuring species diversity by using PAST3 software (Kumar et al., 2022). We also performed similarity of percentages analysis (SIMPER) to identify the species which were contributing the most to differences in communities spatiotemporially (Umar et al., 2022).

Species composition
In our study, 4008 ground beetle individuals were collected, belonging to 11 genera and 18 species and representing five subfamilies, nine tribes. Brachininae (7 species) and Harpalinae (6 species) were two most dominant subfamilies. Genus Pheropsophus (6 species) was dominant genus in the study area (Table I). We considered all those species dominant comprising over 5% were considered dominant species whereas those who showed at least 1% abundance were designated as common species in a given habitat.   Relative abundance Pheropsophus lissoderus (24.33%) was the most abundant species followed by Pheropsophus catoirei (13.17%), Poecilus Versicolor (7.19%) and Pheropsophus africanus (6.89%) whereas the least relative abundance was recorded for Galerita lecontei (0.85%), and Brachinus bilineatus (0.77%) (Fig. 1).

Community diversity
Species richness and the abundance was the highest in Malkwal (16 species and 1969 specimens), followed by Phalia (16 species and 1248 specimens), and Mandi Bahauddin (14 species and 791 specimens). The diversity indices show that maximum diversity has been recorded from Phalia (D = 0.125) followed by Malakwal (D = 0.108) and Mandi Bahauddin (D = 0.098). Shannon (H) index points to that the highest richness of ground beetles was present in Malakwal (2.51) followed by Mandi Bahauddin (2.5) and Phalia (2.4). Highest evenness was observed at Mandi Bahauddin (e^H/S = 0.87) followed by Malakwal (e^H/S = 0.77) and Phalia (e^H/S = 0.72). Similar trend in the values of the other indices were observed (Table II).   (Table III).

DISCUSSION
In this study, 4008 carabid beetles belonging to 11 genera and 16 species were collected, which is comparable to the species recorded in Sukkur (05 species) (Soomro et al., 2021), Haripur (03 genera and 05 species) (Bibi and Rehman, 2020), and Chakwal (21 species and 11 genera; (Mishkatullah, 2018). We recorded 14 species common in all three subdivisions with Pheropsophus lissoderus was most abundant in all three locations. Phalia and Mandi Bahauddin tehsils have extended suburbs with sugarcane, rice and wheat as major crops.
Pheropsophus lissoderus (24.33%) was the most abundant species followed by Pheropsophus catoirei (13.17%) and Poecilus versicolor (7.19%). In Malakwal, we observed only five species which were dominant ≥ 5 % abundance as compared to six in Phalia and ten in Mandi Bahauddin. Agroecosystems are expected to harbor decreased number of ground beetles because of their sensitivity habitat modification and agricultural practices (Rischen et al., 2022). Ground beetle assemblages have shown associations with broad habitat types (Niemelä et al., 1992) and individual ground beetle species affect community structure (Clark et al., 1997). Malakwal showed the higher values of indices (Shannon index: 2.51; Brillouin: 2.486) which may be owed to less anthropogenic disturbance (except for agricultural practices) as compared to Phalia and Mandi Bahauddin. Malakwal, Phalia and Mandi Bahauddin being an agricultural lands with dominant vegetation includes citrus fruits, wheat, sugarcane and rice (Hussain et al., 2020).
In our study area, habitat type at local scale was either crops or field margins surrounded with tree plantation or interspersed citrus plants in all study sites. This has provided favorable microenvironment for the ubiquitous species to be distributed equally in all three sites. Higher diversity was recorded in the heterogeneous habitat which provides diverse niches and more means for resources utilization as compared to homogenous habitat (Liu et al., 2015). However, earlier reported that the isolation from the herbaceous habitats increase carabid species richness and abundance (Uzman et al., 2020). Ground beetles have shown non-significant difference in diversity between forest and agricultural fields (Avgın, 2006).
Predatory ground beetles have limited food options in agricultural landscapes, therefore, track resources around field margins. Ground beetles with a predatory life style were found in greater proportion the crop fields as compared to the grasslands (Hanson et al., 2016). Phytophagous ground beetles are directly affected by the disruption of agricultural landscapes and vegetation (Bommarco, 1998). All these factors contribute to the lower diversity at Mandi Bahauddin which is characterized by more habitat disruption as compared to Phalia and Malakwal where more land is arable and vegetation cover is dense.

CONCLUSION
In conclusion, our results show that ground beetle assemblages in the district Mandi Bahauddin have relatively greater diversity and abundance compared to number of species and their abundance reported from other districts of Pakistan. These results imply that predatorprey relationship have existed in these croplands which suggested that these generalist predator communities. Our results suggest that ground beetle fauna in Mandi Bahauddin could serve as natural biological control agents. Our study reported Poecilus versicolor for the first time from Pakistan.

IBR approval
This study was approved by the Ethical Committee of the University of Gujrat.

Funding
There is no funding available for this research.

Ethical statement
All efforts were taken to minimize pain and discomfort to the animal while conducting this research according to the ethical protocol of the University of Gujrat.

Statement of conflict of interest
The authors have declared no conflict of interest. Zajicek, P., Welti, E.A., Baker, N.J., Januschke, K., Brauner, O. and Haase, P., 2021. Long-term data reveal unimodal responses of ground beetle abundance to precipitation and land use but no changes in taxonomic and functional diversity. Sci.