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Cultivation of crops in salt-affected soils is a major challenge for growers. Despite the use of multiple amendments, salinity stresses adversely affect the crops to some extent. On the other hand, imbalance in the use of boron (B) as a nutrient also creates toxicity. Mismanagement of B fertilizer application decreases the growth and yield of crops. It is necessary to study in depth the adverse effects of salinity and B toxicity. This is why the current research work was conducted in a glass house at Murdoch University, Perth, Australia. The aim of study was to investigate the influence of salinity and B toxicity on carbohydrate partitioning, growth, and ionic composition of two Australian wheat varieties. There were four treatments, i.e., control, high B (15 kg ha−1), salinity (15 dS m−1), and B + salinity. The results showed that the salt-tolerant Halberd (HB) variety accumulated more Na+, B, and Cl− in their leaf sheath and kept the leaf blades free of these toxic ions as compared to the sensitive variety Westonia (WS). Water-soluble carbohydrate (WSC; i.e., glucose, sucrose, fructose, and fructans) concentration increased in response to individual as well as combined constrains of soil salinity and toxic B in the leaf blade of both tolerant and sensitive wheat varieties, but the increase was higher in the tolerant variety as compared to the sensitive one. The concentration of WSCs in leaf sheath of the salt-tolerant wheat variety was increased in response to stress conditions, but those remained low in salt-sensitive ones. Therefore, the salt-tolerant HB genotype was found to be a good source for future wheat breeding programs or to be grown by farmers in B toxic, saline, and B toxic–saline conditions.

Dechlorane Plus (DP) is an unregulated, highly chlorinated flame retardant. It has been manufactured from past 40 years but its presence in the environment was initially reported in 2006. Later, it has been found in various biotic and abiotic environmental matrices. However, little attention has been paid to monitor its presence in Asia. Many studies have reported the occurrence of DP in the environment of Asia, yet the data are scarce, and studies are limited to few regions. The objective of present review is to summarize the occurrence, distribution, and toxicity of this ubiquitous pollutant in various environmental matrices (biotic and abiotic). DP has also been reported in the areas with no emission sources, which proves its long-range transport. Moreover, urbanization and industrialization also affect the distribution of DP, i.e., high levels of DP have been found in urban areas relative to the rural. Tidal movement also incorporates in transport of DP across the aquatic system. Further, bioaccumulation trend of DP in various tissues is kidney > liver > muscle tissues, whereas, blood brain barrier resists its accumulation in brain tissues. Additionally, gender-based accumulation trends revealed high DP levels in females in comparison to males due to strong metabolism of males. Furthermore, methodological aspects and instrumental analysis used in previous studies have also been summarized here. However, data on biomagnification in aquatic ecosystem and bioaccumulation of DP in terrestrial food web are still scarce. Toxicity behavior of syn-DP and anti-DP is still unknown which might gain the interest for future studies.

In Pb-factored soils, soil application of appropriate inorganic amendment along with cultivation of salt-tolerant crop species/genotypes for Pb immobilization can be a good choice. Hence, in saline-sodic and non-saline/sodic Pb-factored soils, Pb immobilization was observed as influenced by exogeneously applied inorganic amendments. Salt-tolerant rice cultivar Shaheen basmati was grown in present study. The current pot study consists of two factors: three inorganic amendments (i.e., gypsum, rock phosphate and di-ammonium phosphate) each with their three increasing rates along with uncontaminated and contaminated controls, and two types of Pb-factored soils (non-saline/sodic and saline–sodic). At harvest maturity, crop was reaped and straw, paddy yields and height of plant were noted. The results showed that Pb induced decrease in rice growth and physiological attributes (i.e., transpiration rate, photosynthetic rate, stomatal conductance, chlorophyll a, b and carotenoids) were significantly (p ≤ 0.05) counteracted by exogeneously applied inorganic amendments. Among the tested amendments, the highest gypsum application rate of 9 me Ca 100 g−1 soil was proved the most effective to improve rice growth, yield, physiological functions, and to reduce Pb concentration in rice both in saline-sodic and non-saline/sodic Pb-factored soils.

Combined salinity and toxic levels of B are usually found in the soils and ground water of arid and semi-arid regions. A pot study was conducted to evaluate the effect of combined stresses of B toxicity and salinity on the growth, yield, physiological and biochemical processes of wheat. The study comprised of twelve treatments including four levels of B (control, 2.5, 5 and 7.5 mg kg-1 ) and three levels of salinity (control, 100 and 200 mM NaCl). The results showed that at lower level of B i.e., 2.5 mg kg-1 , the growth, yield and physiological attributes of wheat were improved at both levels of salinity. While the higher B levels (5 and 7.5 mg kg-1 ) and salinity together reduced wheat growth, photosynthetic and transpiration rates, stomatal conductance and yield. However, this decrease was higher in sensitive wheat genotype than tolerant one. The activity of antioxidant enzymes increased with increasing salinity and B stresses either alone or in combination. An antagonistic salinityB interaction was observed as the reduction in growth and yield parameters in the presence of combined salinity and toxic B levels was less than the sum of reduction caused by individual salinity and toxic B.

Modern civilization with the rapid growth in population, large scale urbanization and industrialization around the globe, results in deterioration of soil and irrigation water quality. It is becoming necessary to understand the responses of crops towards these environmental issues. Among various abiotic stresses, salinity is considered an important limiting factor for worldwide wheat production. High levels of boron (B) and salinity are a serious constraint to crop production around the world. Cropping on saline and B toxic land is restricted by the low tolerance of agricultural crops to these abiotic factors. Frequently, B and salt occur together, however, it is unknown whether the interactions of B and salt increase or decrease the tolerance of a plant to both of these stresses. Low concentration of B is essential to plant growth and may limit the plant growth and development in excess quantity especially under saline conditions. In this chapter the individual and interactive effects of salinity and boron toxicity on physiological and biochemical process in plants have been reviewed.

XRD and photomicrographs of the low-grade, siliceous bauxite ore samples from the Sultan Mehdi, Chamil More, Niaz and Nadi mines showed that they comprise mainly boehmite, kaolinite and quartz. The samples were first calcined at 750 degrees C and then ground to minus 20 mesh prior to H2SO4 leaching. Filtering of the leached slurry produced a pregnant solution of Al2(SO4)3 which was calcined at 900 degrees. The results from treatment with ethanol to remove iron impurities were not encouraging and this step was omitted from tests. All samples, except that from the Nadi mine, gave reasonable recoveries of alumina from the sulphuric acid process (30.44% to 35.15%)., XRD and photomicrographs of the low-grade, siliceous bauxite ore samples from the Sultan Mehdi, Chamil More, Niaz and Nadi mines showed that they comprise mainly boehmite, kaolinite and quartz. The samples were first calcined at 750 degrees C and then ground to minus 20 mesh prior to H2SO4 leaching. Filtering of the leached slurry produced a pregnant solution of Al2(SO4)3 which was calcined at 900 degrees. The results from treatment with ethanol to remove iron impurities were not encouraging and this step was omitted from tests. All samples, except that from the Nadi mine, gave reasonable recoveries of alumina from the sulphuric acid process (30.44% to 35.15%).

Proactive self-configuration is indispensable for MANETs like ubiquitous sensor networks (USNs), as component devices of the network are usually exposed to natural or man-made disasters due to the hostile deployment and ad hoc nature of the USNs. Network state beacons (NSBs) are exchanged among the key nodes of the network for crucial and effective monitoring of the network for steady state operation. The rate of beacon exchange (F/sub E/) and its contents, define the time and nature of the proactive action. Therefore it is very important to optimize these parameters to tune the functional response of the USN. This paper presents a comprehensive model for monitoring and proactively reconfiguring the network by optimizing the F/sub E/. The results confirm the improved throughput while maintaining QoS over longer periods of network operation.