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Soil moisture is an important state variable for land-atmosphere interactions. It is a vital land surface variable for research on hydrology, agriculture, climate, and drought monitoring. In current study, a soil moisture data assimilation framework has been developed by using the Community Land Model version 4.5 (CLM4.5) and the proper orthogonal decomposition (POD)-based ensemble four-dimensional variational assimilation (PODEn4DVar) algorithm. Assimilation experiments were conducted at four agricultural sites in Pakistan by assimilating in-situ soil moisture observations. The results showed that it was a reliable system. To quantify further the feasibility of the data assimilation (DA) system, soil moisture observations from the top four soil-depths (0–5, 5–10, 10–20, and 20–30 cm) were assimilated. The evaluation results indicated that the DA system improved soil moisture estimation. In addition, updating the soil moisture in the upper soil layers of CLM4.5 could improve soil moisture estimation in deeper soil layers [layer 7 (L7, 62.0 cm) and layer 8 (L8, 103.8 cm)]. To further evaluate the DA system, observing system simulation experiments (OSSEs) were designed for Pakistan by assimilating daily observations. These idealized experiments produced statistical results that had higher correlation coefficients, reduced root mean square errors, and lower biases for assimilation, which showed that the DA system is able to produce and improve soil moisture estimation in Pakistan. [ABSTRACT FROM AUTHOR]

Purpose: Salt stress poses a threat to wheat performance that can be managed by silicon application. Therefore, the current short term experiment was aimed to learn the effect of silicon on the defense system, ionic composition and growth of wheat in the presence and absence of salt stress. Methods: In the current experiment, the influence of silicon (6 mM) on anti-oxidative potential and dry matter yield of wheat genotypes (salt sensitive; Fareed-06 and salt tolerant; Inqlab-91) was studied under saline (10 dS/m) and control (2 dS/m) hydroponic solutions. The whole Si was applied to the pots of the Si+ treatment (6 mM) using calcium silicate solution. CaCl2 solution was applied to the pots of the Si-deficient treatment to balance the same total of Ca as in the Si+ treatment to obtain the sole effect of Si. Various ionic, biochemical and growth parameters of wheat plants were recorded after 34 days of transplanting according to standard procedures. Results: Silicon addition to the hydroponic solution increased wheat seedling weight, K:Na with limited Na and enhanced K uptake. Moreover, Si increased chlorophyll chl a/b ratio and promoted the actions of superoxide dismutase (SOD) and catalase (CAT). Conclusions: It can be concluded that silicon supplementation improved the wheat growth and plant defense suppressed by the salt applied. Further, salt tolerant variety gave better performance than the salt sensitive variety. [ABSTRACT FROM AUTHOR]

Climate change over mountainous basins necessitates thorough understanding of present and future temperature and precipitation regimes for better water resource management, cryospheric resources, hydropower generation, natural hazard risk assessment, and ecosystem response. Global and regional climate models (GCMs/RCMs) do not represent valley/ridge scale interactions well. There are inherent model biases due to coarser reorientation of model forcings. The present study is an attempt to use the statistical downscaling model (SDSM) to calibrate and validate Canadian Earth System Model (CanESM2) outputs. The outputs have been compared with corresponding in situ observations available at six meteorological stations within the Kashmir basin in western Himalayas. Daily temperatures and precipitation records during present and future time slices have been considered. The three Representative Concentration Pathways (RCPs) were divided into three future time slices of 2030s, 2060s, and 2090s. Downscaled climate data reveals increase of the mean maximum temperature in the range of 0.3–2.3 °C and the mean minimum temperature increase from 0.3–1.9 °C under different RCPs when compared with the baseline period of 1980–2010. An increasing trend from 2 to 17% at different meteorological stations under different RCPs has been observed in precipitation. Seasonally, autumn shows the highest variability both in temperature and precipitation followed by spring. [ABSTRACT FROM AUTHOR]

In the 1960s, Lake Chad (LC) was one of the largest inland water body on the earth and since then, it has extremely shrunk from a surface area of 25,000 km2 to 2000 km2. The present study determines hydro-climatic changes in the active parts of the Lake Chad basin by using trend analysis and the causes of declining stream flow to LC due to human interventions and climate variability by using a hydrological approach. One approach, which is used to estimate changes in stream flow due to climate variability, is also modified in this study. Trend results showed that mean temperature exhibited very strong increasing trends, with a mean rise of 1.4 °C for 1951–2015, while precipitation presented very weak to strong declining trends, with an overall decline of 15%. Regarding stream flow, all major rivers showed very strong downward trends, resulting in 67% decline. The northern and eastern regions were the most impacted areas in the basin regarding decreasing precipitation and increasing temperature. The hydrological approach showed that decreasing stream flow to LC varied between 34% and 45% in different decades. In general, human activities attributed a 66% decline in stream flow and climate variability 34% for the impacted period (1972–2013) relative to 1951–1971. Only during 1982–1991, climate variability caused most reduction (59% of total) in stream flow because of devastating drought during this period. Since stream flow to LC was mostly affected by human activities, proper water resources planning and sustainable management are necessary but under the umbrella of considering changing climate. Unlabelled Image • Impacts of climate variability and human activities were assessed using hydrologic approach. • Human activities caused more reduction (66%) in inflow to Lake Chad than climate variability. • Climate variability was assesses using Mann-Kendal and Sen's slope methods. • Highly significant increasing trends were observed, with an increase of 1.4 °C/65 yrs. • Moderate signals of decreasing trends were explored, with decline of 15%/65 yrs. [ABSTRACT FROM AUTHOR]

• First study generated naturalized streamflow and assesses environmental flow for all tributaries of the Amudarya River. • The estimated environmental flow ranged from 25 to 46% of naturalized mean annual flow (MAF) for all tributaries. • Current environmental flow (2–5% of MAF) is extremely lower than the estimated one for the delta region. • Environmental conditions are severely damaged in the middle and lower reaches. The Amudarya River (ADR) is the largest source of freshwater in Central Asia providing livelihood to millions of people by extracting water for agriculture. However, the over-exploitation has created some critical environmental issues. For example, almost no water for the delta and the Aral Sea, which was once the 4th largest lake in the world. The present study focused on the assessment of environmental flow requirements (E-flows) in the basin. However, the main challenges in the accomplishment were the unavailability of natural streamflow, which is necessary for E-flow assessment, and sparse and limited hydroclimatic data. A hydrologic model was configured to simulate naturalized streamflow using the meteorological data from the Climate Research Unit. Four hydrological methods (i.e., Tennant, low flow index (7Q 10), flow duration curve analysis (Q 90 , and Q 95), and flow duration curve shifting (FDCS)) and all-method mean were applied to estimate E-flows at 34 sites on all tributaries of the ADR. According to FDCS, 7Q 10 , Q 90 , and Q 95 , E-flows should be 46%, 37%, 30%, and 25% of naturalized mean annual flow (NMAF), respectively, and on average, it should be 35% of NMAF, assessed by the all-methods mean. For low-flow (October–March) and high-flow (April–September) months, E-flows were determined to be 20–30% and 40–98% of NMAF, respectively. E-flow evaluation with the current environmental conditions showed very serious concerns because no sites met the environmental flow requirements below Kerki. This study will be guidelines to improve the riverine ecosystem and for future sustainable development in the region. [ABSTRACT FROM AUTHOR]

Abstract The behavior of a cell can be described through tissue morphogenesis, which involves the migration, division or death of tissue, and is regulated with the molecular scale. Automated cell detection from microscopy image has become an important step in cell-based experiments. We have developed a method to detect abnormal behavior of the cell through real-time images. Our method consists of pixel classification using K-Means and Bayesian classification. It is based on the combination of gray level threshold. Furthermore, Fast Fourier Transfer (FFT), covariance coefficient and verification of cell variation were applied to investigate the cells after drug injection. We have considered different types of confocal microscopy images. The images were taken after every five min. The NL1 compound has high fluorescent, which selectively targets the mitochondria, and mitochondria are sensitive to the environmental changes. Identification of cells in a TPEF probe test is very important for determining cell abnormalities. Detection of abnormal cells is very crucial in the early stage diseases, and it is beneficial for mitochondrial microenvironment related diseases. [ABSTRACT FROM AUTHOR]

Boron (B) is an important micronutrient required for plant growth. In this study, the importance of B application at different developmental stages was investigated to see its impact on grain yield, plant vigor and quality parameters of fine grain rice cultivars. The experimental soil was light textured (loam), and was very low in soil organic matter and soil B contents. Boron was applied as i) soil application (7.5 kg ha-1), ii) foliar application (1.5 g B L-1 of water) at booting stage, and as iii) soil + foliar application, with untreated control. The results indicated that B application substantially improved the paddy yield. In this regard, dual application of boron proved to be the most effective for improvement in morphological, yield and quality parameters (milling recovery and cooking quality) of rice. Dual application of B (soil application + foliar application) improved the paddy yield by 18.5% in Super Basmati and 30.2% in Basmati 515. B application also reduced the panicle sterility in rice. In conclusion, B should be applied as basal + foliar treatment to improve the grain yield, milling recovery, cooking quality, and to reduce the panicle sterility in rice. [ABSTRACT FROM AUTHOR]

We present the climate change impact on the annual and seasonal precipitation over Rajang River Basin (RRB) in Sarawak by employing a set of models from Coupled Model Intercomparison Project Phase 5 (CMIP5). Based on the capability to simulate the historical precipitation, we selected the three most suitable GCMs (i.e. ACCESS1.0, ACCESS1.3, and GFDL-ESM2M) and their mean ensemble (B3MMM) was used to project the future precipitation over the RRB. Historical (1976-2005) and future (2011-2100) precipitation ensembles of B3MMM were used to perturb the stochastically generated future precipitation over 25 rainfall stations in the river basin. The B3MMM exhibited a significant increase in precipitation during 2080s, up to 12 and 8% increase in annual precipitation over upper and lower RRB, respectively, under RCP8.5, and up to 7% increase in annual precipitation under RCP4.5. On the seasonal scale, Mann-Kendal trend test estimated statistically significant positive trend in the future precipitation during all seasons; except September to November when we only noted significant positive trend for the lower RRB under RCP4.5. Overall, at the end of the twenty-first century, an increase in annual precipitation is noteworthy in the whole RRB, with 7 and 10% increase in annual precipitation under the RCP4.5 and the RCP8.5, respectively. [ABSTRACT FROM AUTHOR]