Integration of Satellite Image Derived Temperature and Water Depth for Assessing Fish Habitability in Dam Controlled Flood Plain Wetland

The present study attempted to investigate the changes in temperature conducive to fish habitability during the summer months in a hydrologically modified wetland following damming over a river. Satellite image-driven temperature and depth data calibrated with field data were used to analyse fish habitability and the presence of thermally optimum habitable zones in some fishes such as Labeo Rohita, Cirrhinus mrigala, Tilapia fish, Small shrimp, and Cat fishes. The study was conducted both at the water's surface and at the optimum depth of survival. It is very obvious from the analysis that a larger part of wetland has become an area that destroyed aquatic habitat during the post-dam period and existing wetlands have suffered significant shallowing of water depth. This has resulted in a shrinking of the thermally optimum area of fish survival in relation to surface water temperature (from 100.09 km2 to 74.24 km2 before the dam to 93.97 km2 to 0 km2 after the dam) and an improvement in the optimum habitable condition in the comfortable depth niche of survival. In the post-dam period, it increased from 75.49 % to 99.765%. Since the damming effect causes a 30.53 to 100% depletion of the optimum depth niche, improving the thermal environment has no effect on fish habitability. More water must be released from dams for restoration. Image-driven depth and temperature data calibrated with field information has been successfully applied in data sparse conditions, and it is further recommended in future work.

Effect of Tillage and Irrigation Methods on the Productivity, Profitability and Nutrient Uptake of Wheat

Tillage and crop establishment method play an important role in the placement of seed at proper depth which ultimately affect germination and crop growth. The selection of suitable crop establishment method for wheat is dependent upon the time of sowing and availability of soil moisture. A field experiment was conducted during Rabi season 2017-18 and 2018-19 to evaluate the effect of tillage and crop establishment methods on productivity, nutrient uptake and profitability of wheat (Triticum aestivum L.). Results revealed that grains, straw and biological yields were significantly higher under treatment T5 (wide bed furrow irrigated) and at par with T2 (furrow irrigated with gated pipe Raised bed) and T8 (zero till flat irrigated by gated pipe Controlled flood irrigation).Total nitrogen, phosphorus and potassium uptake were significantly more in treatment T5 than other treatments. Significantly maximum gross return (97818 ₹ ha-1), was recorded under T5 which was at par with T8 and T2. The maximum net return (61910 ₹ ha-1) and B: C ratio (2.84) were fetched under T8 than all other treatments followed by and T5.

Supplemental Material: Estimating the contribution of tributary sand inputs to controlled flood deposits for sandbar restoration using elemental tracers, Colorado River, Grand Canyon National Park, Arizona

The mean reported concentration and standard error for all elemental XRF data and the proportion of total variance between Glen Canyon and Paria River sand populations explained by the first five principal components in each grain size.

Supplemental Material: Estimating the contribution of tributary sand inputs to controlled flood deposits for sandbar restoration using elemental tracers, Colorado River, Grand Canyon National Park, Arizona

The mean reported concentration and standard error for all elemental XRF data and the proportion of total variance between Glen Canyon and Paria River sand populations explained by the first five principal components in each grain size.

Assessment of the geomorphic effectiveness of controlled floods in a braided river using a reduced-complexity numerical model

Most Alpine rivers have undergone significant alterations in flow and sediment regimes. These alterations have notable effects on river morphology and ecology. One option to mitigate such effects is flow regime management, specifically through the reintroduction of channel-forming discharges. The aim of this work is to assess the morphological changes induced in the Piave River (Italy) by two distinct controlled-flood strategies, the first characterized by a single artificial flood per year and the second by higher-magnitude but less frequent floods. This work involved applying a two-dimensional reduced-complexity morphodynamic model (CAESAR-LISFLOOD) to a 7 km long reach, characterized by a braided pattern and highly regulated discharges. Numerical modelling allowed the assessment of morphological changes for four long-term scenarios (2009–2034). The scenarios were defined considering the current flow regime and the natural regime, which was estimated by a stochastic physically based hydrologic model. Changes in channel morphology were assessed by measuring active-channel width and braiding intensity. A comparison of controlled-flood scenarios to a baseline scenario (i.e. no controlled floods) showed that artificial floods had little effect on channel morphology. More channel widening (13.5 %) resulted from the high-magnitude flood strategy than from the application of the other strategy (8.6 %). Negligible change was observed in terms of braiding intensity. The results indicate that controlled floods do not represent an effective solution for morphological recovery in braided rivers with strongly impacted flow and sediment regimes.

Assessment of geomorphic effectiveness of controlled floods in a braided river using a reduced-complexity numerical model

Most Alpine rivers have undergone strong alteration of flow and sediment regimes. These alterations have notable effects on river morphology and ecology. One option to mitigate such effects is the flow regime management, specifically by the re-introduction of channel-forming discharges. The aim of this work is to assess the morphological changes induced in the Piave River (Italy) due to two different controlled flood strategies, the first characterized by a single artificial flood per year and the second by higher magnitude, but less frequent, floods. The work was carried out applying a 2D reduced-complexity morphodynamic model (CAESAR-LISFLOOD) to a 7 km-long reach, characterized by a braided pattern and highly regulated discharges. The numerical modelling allowed the assessment of morphological changes for four long-term scenarios (2009–2034). The scenarios were defined taking into account the current flow regime and the natural regime, which was estimated by a stochastic physically-based hydrologic model. Changes in channel morphology were assessed by measuring active channel width and braiding intensity. Comparing controlled flood scenarios to a baseline scenario (i.e., no controlled floods) it turned out that artificial floods had small effects on channel morphology. The highest channel widening (13.5 %) was produced by the release strategy with higher magnitude floods, while the other strategies produced lower widening (8.6 %). Negligible change was observed in terms of braiding intensity. Results pointed out that controlled floods may not represent an effective solution for morphological recovery in braided rivers strongly impacted in their flow and sediment regimes.