A Proposal for Improving Pastures in Subsistence Farming Systems on the East India Plateau

The East India Plateau (EIP) experiences deep poverty despite high rainfall (\u3e 1200 mm). Livelihoods, once derived from Sal (Shorea robusta) forest, now depend on agriculture. Subsistence farmers practice monoculture rice-fallow on small, fragmented landholdings (total \u3c 1 ha). Rice in the undulating landscape was traditionally grown in lowland drainage lines (Fig. 1) but population pressure has forced it onto adjacent terraced slopes (medium-uplands) that now comprise \u3e 80% of the rice area (\u3e 50% of land area). Rice is protected from grazing, but the watershed is otherwise grazed as common land with no pasture management. Grazed uplands are often degraded and unproductive, receiving no inputs. Livestock are limited to large animals providing draft power (males) and manure (fuel, compost), and goats for emergency finance. Rainfall is not the primary constraint to production from micro-watershed ecosystems of the EIP-improved rainfed cropping would deliver immediate substantial benefits, without watershed development (Cornish et al., 2015a); although low soil fertility requires attention (Agarwal et al., 2010). The next step in development requires a strategy for poor, risk-averse smallholders to improve grazing land. This paper develops a proposal for evaluation, using a soil fertility survey of seven watersheds combined with botanical observations and published work

An integrated approach to improving rural livelihoods: Examples from India and Bangladesh

This paper presents an overview of work in West Bengal, Andhra Pradesh and SW Bangladesh through a series of projects from 2005 to the present, considering the impact of farming systems, water shed development and/or agricultural intensification on livelihoods in selected rural areas of India and Bangladesh. The projects spanned a range of scales spanning from the village scale (∼  1 km2) to the meso-scale (∼  100 km2), and considered social as well as biophysical aspects. They focused mainly on the food and water part of the food-water-energy nexus. These projects were in collaboration with a range of organisations in India and Bangladesh, including NGOs, universities, and government research organisations and departments. The projects were part funded by the Australian Centre for International Agricultural Research, and built on other projects that have been undertaken within the region. An element of each of these projects was to understand how the hydrological cycle could be managed sustainably to improve agricultural systems and livelihoods of marginal groups. As such, they evaluated appropriate technology that is generally not dependent on high-energy inputs (mechanisation). This includes assessing the availability of water, and identifying potential water resources that have not been developed; understanding current agricultural systems and investigating ways of improving water use efficiency; and understanding social dynamics of the affected communities including the potential opportunities and negative impacts of watershed development and agricultural development.he authors acknowledge funding from the Australian Centre for International Agricultural Research for projects: Water harvesting and better cropping systems for smallholders of the East India Plateau (LWR/2002/100), Impacts of meso-scale Watershed Development (WSD) in Andhra Pradesh (India) and their implications for designing and implementing improved WSD policies and programs (LWR/2006/072), and Promoting socially inclusive and sustainable agricultural intensification in West Bengal and Bangladesh (LWR/2014/072)

Search for eccentric black hole coalescences during the third observing run of LIGO and Virgo

Despite the growing number of confident binary black hole coalescences observed through gravitational waves so far, the astrophysical origin of these binaries remains uncertain. Orbital eccentricity is one of the clearest tracers of binary formation channels. Identifying binary eccentricity, however, remains challenging due to the limited availability of gravitational waveforms that include effects of eccentricity. Here, we present observational results for a waveform-independent search sensitive to eccentric black hole coalescences, covering the third observing run (O3) of the LIGO and Virgo detectors. We identified no new high-significance candidates beyond those that were already identified with searches focusing on quasi-circular binaries. We determine the sensitivity of our search to high-mass (total mass M>70 M⊙) binaries covering eccentricities up to 0.3 at 15 Hz orbital frequency, and use this to compare model predictions to search results. Assuming all detections are indeed quasi-circular, for our fiducial population model, we place an upper limit for the merger rate density of high-mass binaries with eccentricities 0<e≤0.3 at 0.33 Gpc−3 yr−1 at 90\% confidence level

Ultralight vector dark matter search using data from the KAGRA O3GK run

Among the various candidates for dark matter (DM), ultralight vector DM can be probed by laser interferometric gravitational wave detectors through the measurement of oscillating length changes in the arm cavities. In this context, KAGRA has a unique feature due to differing compositions of its mirrors, enhancing the signal of vector DM in the length change in the auxiliary channels. Here we present the result of a search for U(1)B−L gauge boson DM using the KAGRA data from auxiliary length channels during the first joint observation run together with GEO600. By applying our search pipeline, which takes into account the stochastic nature of ultralight DM, upper bounds on the coupling strength between the U(1)B−L gauge boson and ordinary matter are obtained for a range of DM masses. While our constraints are less stringent than those derived from previous experiments, this study demonstrates the applicability of our method to the lower-mass vector DM search, which is made difficult in this measurement by the short observation time compared to the auto-correlation time scale of DM

Search for gravitational-lensing signatures in the full third observing run of the LIGO-Virgo network

Gravitational lensing by massive objects along the line of sight to the source causes distortions of gravitational wave-signals; such distortions may reveal information about fundamental physics, cosmology and astrophysics. In this work, we have extended the search for lensing signatures to all binary black hole events from the third observing run of the LIGO--Virgo network. We search for repeated signals from strong lensing by 1) performing targeted searches for subthreshold signals, 2) calculating the degree of overlap amongst the intrinsic parameters and sky location of pairs of signals, 3) comparing the similarities of the spectrograms amongst pairs of signals, and 4) performing dual-signal Bayesian analysis that takes into account selection effects and astrophysical knowledge. We also search for distortions to the gravitational waveform caused by 1) frequency-independent phase shifts in strongly lensed images, and 2) frequency-dependent modulation of the amplitude and phase due to point masses. None of these searches yields significant evidence for lensing. Finally, we use the non-detection of gravitational-wave lensing to constrain the lensing rate based on the latest merger-rate estimates and the fraction of dark matter composed of compact objects

Modeling the Impact of Watershed Development on Water Resources in India

Integrated Assessment of Scale Impacts of Watershed Interventions is the outcome of a multi-disciplinary research team of social scientists, hydrologists (groundwater and surface water), modellers; and bio-physical scientists who have worked together over five years to develop an integrated model of the sustainability of biophysical, economic and social impacts of watersheds. Impacts of watershed interventions are assessed at upstream, mid-stream and downstream locations of two hydrological units that are characterised with differential bio-physical attributes. The editors propose that watershed interventions, when integrated with hydro-geology and bio-physical aspects, have greater influence on the resilience of the socio-ecological system. This book takes these aspects in to consideration and in the process provides insights in to watershed design and implementation

Improving crop production for food security and improved livelihoods on the East India Plateau. I. Rainfall-related risks with rice and opportunities for improved cropping systems

Rainfed transplanted rice (Oryza sativa) is the staple crop of the East India Plateau (EIP), where it is low yielding and drought-prone despite high annual rainfall (>1200 mm). Although grown traditionally on lowlands associated with drainage lines, population pressure has forced rice onto terraced slopes (medium-uplands) that now comprise >80% of the rice area, and the only rice land for many families. Crop monitoring, soil water measurement and soil water-balance modelling in Pogro watershed (West Bengal) were used to explore rainfall-related risks associated with rice-fallow on medium-upland and to examine opportunities for using rainfall more effectively. The analysis was extended to three more EIP locations by using the model with long-term rainfall. Rice depends on sustained ponding for transplanting and good yields, but in Pogro, failure to meet this condition on medium-uplands led to delayed or failed transplanting and/or periodic or premature draining of fields in five years from 2005 to 2011. Modelled ponding duration was more variable than rainfall. Most farmers have adapted to variable ponding by growing medium-duration varieties on medium-uplands, rather than the longer types grown in lowlands. However, the average ponding duration of 65 days over all four locations was well short of the ~90 days required. Even shorter-duration varieties would provide only a partial solution as ponding was 30 mm available soil water). Duration of available soil water was the least variable measure of water security, confirming that perceptions of 'drought' arise from experience with transplanted rice that depends on ponding. We conclude that 'aerobic' (un-puddled) rice culture on medium-uplands should provide food security from this staple crop. Modelling identified opportunities to intensify and diversify cropping systems with manageable climate risk, even without WSD, by opportunistically using residual water after rice, shorter-duration varieties to maximise residual water, and minimal supplementary irrigation from shallow groundwater that apparently is recharged every year. The suggested developments have implications for river basin hydrology and WSD that require research and a reappraisal of policy

A new look at uncertainty in end member mixing models for streamflow partitioning

Chemical and isotope based hydrograph separation methods, such as end member mixing analysis (EMMA1), have been utilized in recent decades because they offer a better explanation of stream chemistry than can be obtained from flow partitions derived usin

Water harvesting and better cropping systems for the benefit of small farmers in watersheds of the East India Plateau

This paper discusses an integrated approach for water resource management to improve rural livelihoods in the East India Plateau. This has involved linking hydrological, agronomic and social aspects to increase access to water, improve water use efficiency and develop capacity within the villages for better decision making regarding use of the available resources. To this end, the research adopted a participatory, action-learning approach, with villagers joining in developing research questions, executing experiments, collecting data and sharing in their interpretation, as well as planning intervention work designed to improve access to water, particularly in the early dry season. The focus of this paper is on the integration of the different aspects of water resource management, with particular emphasis on the social issues. This included working with women's self-help groups and village watershed committees, and specific efforts to engage women in research and related development activities. The result has been an improved capacity within the village for managing water resources, including improved self-perceptions as farmers (especially women), better understanding of the potential resources and any constraints (e.g. soil fertility) and knowledge of how to manage the constraints (e.g. fertilisers), as well as a better understanding of the social capacities within the village