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In this study, the impacts of changes in land use/ land cover (LULC) and climate on surface runoff are investigated in the Kadalundi river basin, Western Ghats, India. Land Change Modeller (LCM) was applied to project the future LULC scenarios in 2030 and 2050. Climate change scenarios of the future time period of near (2011−2040), mid (2041−2070), and far (2071−2099) were procured for Representative Concentration Pathway (RCP) 4.5 and 8.5 emission scenarios from five different general circulation models of coordinated regional downscaled experiment project. The 1988 and 2000 LULC were used for projection of 2014 LULC and validated with actual 2014 LULC. Further, 2000 and 2014 LULC were used for projection of 2030 LULC, and 2014 and 2030 LULC were used to project 2050 LULC. Changes in LULC from 2000 to 2050 are calculated using the transition matrix approach. The impacts of changes in LULC and climate on surface runoff are investigated by the Soil and Water Assessment Tool (SWAT) model. The results showed a decrease in forest and grassland and an increase in agriculture, and urban areas from 2000 to 2050, with an increase in the mean annual surface runoff. For climate change scenarios assessed, mean annual surface runoff in the near, mid, and far would be decreasing under both RCP 4.5 and 8.5 while RCP 8.5 showing more worse condition than RCP 4.5 in the future. The combined effects of changes in LULC and climate showed a decreasing trend in the surface runoff for the near and mid future. Furthermore, the projected results indicate that the surface runoff would be higher in both RCP scenarios during winter and summer; while the monsoon period largely demonstrates a reverse trend. The analysis of combined impacts reveals that the decreasing of surface runoff under RCP 4.5 and 8.5 would be higher in near compared to mid future. [ABSTRACT FROM AUTHOR]

Land uses are pivotal in global carbon cycles. The native forest lands possess a greater potential to sequester higher carbon, which can directly address soil quality and climate change problems. Unfortunately, the rapid conversion of forests to other land use over the past few decades has significantly declined the concentration of carbon in the soils. Therefore, in order to estimate the impact of land-use change (LUC) on soil carbon status, this present study was attempted under major ecosystems (Forest (FOR), cropland (CRP), tea plantation (TEA)) of Conoor. Results from findings revealed that total organic carbon (TOC) concentration and carbon pools were significantly (p<0.05) higher in FOR than in CRP and TEA. TOC (0-45 cm) recorded in FOR, CRP and TEA was 32.88, 11.87 and 18.84 g kg-1 and it decreased along the depth increment. Carbon stock (t ha-1) in FOR, CRP and TEA (0-45cm) was 68.10, 26.04, 42.42. Microbial biomass carbon (MBC) was higher in FOR (283.08 mg kg-1) followed by TEA (94.64 mg kg-1) and CRP (76.22 mg kg-1). The microbial biomass nitrogen (MBN) followed; FOR > TEA > CRP. These results clearly indicate that the LUC has inflicted a greater impact on soil carbon status and its extent was quantified using the land degradation index (LDI). The LDI (0-45 cm) recorded in CRP (-38.65) and TEA (-61.75) signals the need for immediate implementation of carbon management strategies in the CRP and TEA ecosystem to keep the soils of Conoor alive and prevent land degradation. [ABSTRACT FROM AUTHOR]

Transport infrastructure is said to drive development in a region and affect the land use/land cover (LULC) over time. We employ a difference-in-differences (DID) framework to causally examine transport infrastructure as a driver of land use/land cover change (LUCC) using the case study of the Konkan Railway, one of the largest railway projects in post-independence India. Using multi-period multispectral satellite data, we obtained the basic LULC classes for the DID and spatio–temporal analysis. The findings suggest that the Konkan Railway led to an increase in built-up land cover and open spaces at the expense of the agricultural land cover, but did not adversely affect forest cover. This result is consistent all along the 760 km long railway. The study contributes to the emerging literature on the land use impacts of railways and underscores the importance of implementing environmental management measures. [ABSTRACT FROM AUTHOR]

Urbanization is one of the main drivers in the conversion of natural habitats into different land use and land cover types (LULC) which threaten the local as well as global biodiversity. This impact is particularly alarming in tropical countries like India, where ~18% of the world's population live, and its ever-growing economy (i.e., industrial development) expanded urban areas by several folds. We undertook this study to examine the impacts of urbanization (i.e., LULC) on terrestrial vertebrates (mammals, birds, reptiles, and amphibians) in the Mumbai Metropolitan Region (MMR), Western Ghats, India. We sampled different habitats ranged from highly disturbed urban areas to less disturbed forested areas. Multiple sampling methods such as quadrat sampling, line transect, point count, and camera trapping were used to quantify the target taxa. We used multi-species occupancy modeling in the Bayesian framework to estimate detection probability and occupancy and to assess the effect of various LULC on different species. All four groups showed a significant negative impact of increasing anthropogenic habitat cover on occupancy. Out of 213 species detected in this study, 96% of mammals, 85% of birds, 93.75% of amphibians, and 69.43% of reptiles showed a negative effect of anthropogenic habitat cover. Evidence suggests that historical and recent human disturbances could have played an important role in transforming this area from semi-evergreen and moist deciduous forest to open, scrubby, dry deciduous, and fire-prone landscape. This might be the reason for the high occupancy of open and degraded forest habitat preferring species in our study area. We recommend species-rich areas in the MMR, e.g., Karnala Bird Sanctuary (KBS) and Prabalgad-Matheran-Malanggad Hill Range (PMMHR), must be conserved through habitat restoration, ecotourism, public awareness, and policymaking. [ABSTRACT FROM AUTHOR]

Background: Anthropogenic pressure in biodiversity hotspots is increasingly recognized as a major driver of the spillover and expansion of zoonotic disease. In the Western Ghats region of India, a devastating tick-borne zoonosis, Kyasanur Forest disease (KFD), has been expanding rapidly beyond its endemic range in recent decades. It has been suggested that anthropogenic pressure in the form of land use changes that lead to the loss of native forest may be directly contributing to the expanding range of KFD, but clear evidence has not yet established the association between forest loss and KFD risk.Methods: The current study sought to investigate the relationship between KFD landscape suitability and both forest loss and mammalian species richness, to inform its epidemiology and infection ecology. A total of 47 outbreaks of KFD between 1 January 2012 and 30 June 2019 were modelled as an inhomogeneous Poisson process.Results: Both forest loss [relative risk (RR) = 1.83; 95% confidence interval (CI) 1.33-2.51] and mammalian species richness (RR = 1.29; 95% CI 1.16-1.42) were strongly associated with increased risk of KFD and dominated its landscape suitability.Conclusions: These results provide the first evidence of a clear association between increasing forest loss and risk for KFD. Moreover, the findings also highlight the importance of forest loss in areas of high biodiversity. Therefore, this evidence provides strong support for integrative approaches to public health which incorporate conservation strategies simultaneously protective of humans, animals and the environment. [ABSTRACT FROM AUTHOR]

Integrated landscape management of key population areas along with the corridors linking them is important for tiger conservation in the Indian subcontinent. Relationships between gene flow and landscape patterns, however, cannot be generalized given that different limiting factors influence movement in different spatial contexts. Here, we study the landscape features affecting tiger gene flow in the Western Ghats, and examine how and why limiting landscape features differ between Central India and the Western Ghats. We also assess whether these landscape features have been altered by land use changes in the last five decades. Our study area covers 30 000 km2 from Bhadra Tiger Reserve to the Nilgiri Biosphere Reserve in India. We used genetic data of 115 tigers and landscape resistance model optimization to create a resistance surface to gene flow in the Western Ghats. Tiger gene flow, both in Central India and the Western Ghats, is primarily related to topographic roughness and secondarily to diffuse disturbance, however these relations are inverted in the two landscapes ‐ in Central India, gene flow correlates with rough terrain, whereas in the Western Ghats, it correlates with smooth, forested terrain with minimal human disturbance. Topographic complexity is an important factor affecting tiger dispersal, but tiger's response to topography seems to be dependent upon interactions with human‐related disturbance. Tigers in Central India favor rough terrain for dispersal primarily because it is the only part of the landscape without heavy human footprint and the last refuge for natural vegetation, whereas in the Western Ghats, forest cover is more extensive in flatter terrain and human footprint is generally lower. [ABSTRACT FROM AUTHOR]

• A novel framework is presented to simulate baseflow from a 2D groundwater model. • Modelled baseflow shows good fit with baseflow separated using Eckhardt filter. • Baseflow shows a declining trend in the basin but not in the humid region. • A digital filter is used combinedly with the model to simulate baseflow trends. • Basin heterogeneity has caused the distinct hydrologic responses within the basin. A novel framework that integrally uses groundwater and streamflow observations to calibrate a physically based sub surface model to generate base flow on a daily time step is presented in this study. Trend analysis on mean annual base flow time series showed that a declining trend was present in the basin though the upstream humid region was devoid of any trend. GLUE analysis was adopted to the simulation of base flow in the humid region and the most sensitive parameters were identified as the recharge factor (rf) and discharge factor (pd). The model was able to satisfactorily simulate base flow as observed values fell within the 95CI bands for the calibration period. The mean annual BFI values were computed at Muthankera to be 0.236 ± 0.02. The mean seasonal BFI varied from 48 % during post monsoon periods to 21 % during monsoon periods. The base flow simulated by the model was comparable to the output from the Eckhardt filter which has been widely cited to be a suitable baseflow separation method for many river basins. Due to the absence of groundwater level data in the transition region, a combination of model and digital filter was used to calibrate that region. The draft from the groundwater storage computed from the model was found to be highly nonlinear. The rf was seen to be lower and pd to be higher in the transition region than in the humid region. This would imply that in the transition region, the base flow is generated more gradually in comparison to the humid region. This was characteristic of forested basins where the uptake of water by deep rooted trees during evapotranspiration from the unsaturated zone causes delay in the water table response which in turn could result in delay in the base flow generation process. The consequence of the calibration exercise on Kabini basin was establishing that the heterogeneity in terms of precipitation and land use has resulted in the distinct hydrologic responses from the two regions in the basin. [ABSTRACT FROM AUTHOR]

Abstract: Human-modified tropical landscapes under semi-natural or agro-ecosystems often harbor biodiversity of significant conservation value. In the Western Ghats of India, these ecosystems also provide connectivity between protected areas and other remnant forests. We investigated the conservation value of these landscapes and agro-ecosystems using results from 35 studies covering 14 taxonomic groups. Large, conspicuous taxonomic groups and tree-covered land-use types have received much focus in this area of research in the Western Ghats. We computed a response ratio defined as the log ratio of species richness in human land use to species richness in forest control site from 17 studies. In a meta-analysis, we investigated variation of this ratio across studies with respect to three variables: taxonomic group, the land-use type sampled and the extent of forest cover within the study landscape. Higher forest cover within the landscape emerged as a major positive influence on biodiversity in human-modified landscapes for vertebrates and vegetation while no patterns emerged for invertebrates. Our results suggest that loss of remnant forest patches from these landscapes is likely to reduce biodiversity within agro-ecosystems and exacerbate overall biodiversity loss across the Western Ghats. Conservation of these remnant forest patches through protection and restoration of habitat and connectivity to larger forest patches needs to be prioritized. In the densely populated Western Ghats, this can only be achieved by building partnerships with local land owners and stakeholders through innovative land-use policy and incentive schemes for conservation. [ABSTRACT FROM AUTHOR]

Human land use and activity results in the loss of habitat and biodiversity, and alters how animals move through landscapes. Spatially explicit information on where animal movement is affected at large spatial scales is crucial for prioritizing conservation efforts. We evaluated landscape permeability to movement in two conservation priority landscapes in India, the Western Ghats (WG) and Central India (CI). Using an agent-based model we simulated movement and dispersal of five wide-ranging species in WG (elephant, gaur, leopard, sambar and sloth bear) and four in CI (gaur, leopard, sambar and sloth bear). For each species we compared movement in the presence and absence of land-use land-cover, infrastructure and human population to identify areas where movement is impeded and reduced due to high-resistance features; unrestricted due to relatively low-resistance features; and increased and channelled due to surrounding high-resistance areas. In both landscapes, median movement was reduced. Human land-use, human population and high linear infrastructure density contribute the highest to impeded movement for all species. Natural areas constitute only 20–55% and 50–70% of unrestricted, increased and channelled movement areas in WG and CI respectively. This suggests that a large percentage of the landscape crucial for maintaining movement is not completely permeable. Such areas are often neglected in conservation planning. Our spatially explicit results help identify and prioritize areas where restoration or mitigation should be planned to improve permeability to movement for large mammals. Our approach can be used for other landscapes where data on large mammal movement is lacking. • Median permeability to movement for all species in both landscapes was reduced. • Reduced movement is due to human land-use, human population and linear infrastructure. • Natural areas occupy only 20–55% of high permeability areas in WG and 50–70% in CI. • Thus permeability is not complete in areas crucial for movement. • Our spatially explicit results help prioritize restoration and mitigation measures. [ABSTRACT FROM AUTHOR]

• Secondary satellite datasets were considered for developing fire susceptibility maps. • Usage of Susceptibility maps for estimating effects of fire on water balance was proposed. • Highly susceptible sub basins were analysed for variations in lateral and surface flow. • Around 21.16% increase in burnt area was estimated in 2017 when compared to 2005. • Around 30.83% increase in streamflow between pre and post fire scenarios was observed. Sudden and long term changes in the landscape can be attributed to periodic wildfires which, is a cyclic occurrence at Kudremukh national forest in Western Ghats of India. These land-use changes influence the hydrology of landscape, causing disintegration of soil, loss of biodiversity, changes in stream and flooding. To understand and account for these land-use changes, a new approach was implemented by developing fire susceptibility map from topographic, climatic and human-induced factors and validating it with MODIS (Moderate-resolution Imaging Spectro-radiometer) fire points for discretising accuracy. The fire susceptibility map can be used for studying the long-term (year or more) effects of fire on water balance systems. The fire susceptibility map generated for the years 2005 and 2017 was overlaid with MODIS LULC (Land Use Land Cover) for establishing the post-fire scenario whereas MODIS LULC MCD12Q1 (2005 and 2017) was considered as the no-fire scenario to analyse the intensity of the fire and its effect on streamflow and infiltration. These maps along with historical satellite hydro-climatic datasets, were used to assess the effect of forest fire on hydrological parameters using the SWAT (Soil and Water Assessment Tool) model. No-fire and post-fire conditions were established by modifying SCS-CN (Soil Conservation Service-Curve Number) based on previous works of literature to represent the catchment as unburnt and burnt area. The SWAT model was calibrated (2002–2008) and validated (2009–2012) for establishing a baseline scenario. The sensitive parameters obtained from SUFI-2 (Sequential Uncertainty Fitting) algorithm in SWAT-CUP (Calibration and Uncertainty Programs) were used to simulate stream flows till 2017 due to lack of observed streamflow data for the year 2017. It was inferred that the effect of wildfire on flows in recent years (2017) had increased radically when compared to the flows before a decade (2005), diminishing the rate of infiltration and causing the deficit in groundwater to energise. The methodology can further be executed in any forest area for distinguishing fire hazard zones and implementing prior actions in those areas for mitigation of forest fires and maintaining sustainable water balance. [ABSTRACT FROM AUTHOR]