The direct and indirect effects of China's wastewater treatment service on urban household wastewater discharge

Urban household wastewater has surged with the urbanization in China, treatment of which demands attention. Utilizing China’s urban panel data from 2005 to 2015, this article evaluates whether governmental wastewater treatment service changes urban residents’ wastewater-discharging behaviors. The outcomes reveal that: (a) in the short-run when the local government treats more wastewater, the residents discharge more wastewater; (b) this short-run relationship is notably strengthened by household attributes, that is, income and education; (c) in the long-run, the increasing relationship between household wastewater discharge and wastewater treatment service also exists significantly, which calls for immediate attention of policy makers.     

Potential of mixed culture of freshwater prawn (Macrobrachium rosenbergii) and self-recruiting small species mola (Amblypharyngodon mola) in rotational rice–fish/prawn culture systems in Bangladesh

The effects of different stocking densities of freshwater prawn (Macrobrachium rosenbergii) on its growth and production in relation to the presence of small self‐recruiting species mola (Amblypharyngodon mola) were investigated in modified rice fields after rice harvest at Mymensingh, Bangladesh. Keeping the stocking density of mola fixed at 20 000 ha^?1 in each treatment, four densities of freshwater prawn (treatments) were maintained: 10 000, 15 000, 20 000 and 25 000 ha^?1 respectively. The rice plots were limed (CaCO₃) and fertilized with urea, triple super phosphate and cowdung regularly. The prawns were fed daily with commercial pellets. Water quality parameters such as temperature, dissolved oxygen, transparency, pH, total alkalinity, inorganic nitrogen (nitrate, nitrite and total ammonia), chlorophyll a and orthophosphate were determined fortnightly. Numerical analysis of plankton communities was performed monthly. All water quality parameters were found to be within the suitable range for freshwater prawn culture, except high temperature, in the peak summer months. There was a homogenous abundance of plankton communities in all treatments throughout the experimental period. Mola started to breed in the second month of the original stocking with partial harvesting after the second month and continued until the final harvest. The total production of mola ranged between 124 and 152 kg ha^?1 during the 4‐month culture period. The average prawn survival ranged from 49% to 57% without any significant difference among treatments. Freshwater prawn production ranged from 294 to 596 kg ha^?1 with significantly higher production in the treatment where 20 000 ha^?1 freshwater prawn were stocked. This treatment also resulted in a higher net profit margin (74%), indicating that stocking at a combination of 20 000 ha^?1 freshwater prawn and 20 000 ha^?1 mola could be the optimum proposition for prawn–mola culture in modified rain‐fed rice fields after rice cultivation.     

Effects of stocking density, periphyton substrate and supplemental feed on biological processes affecting water quality in earthen tilapia–prawn polyculture ponds

The technical and economic potentials of tilapia, Oreochromis niloticus (L.), and giant river prawn, Macrobrachium rosenbergii (de Man), polyculture in periphyton-based systems are under investigation in an extensive research programme. This article is a combined analysis of data from four experiments exploring the effects of periphyton, fish, prawn and feed on water quality. Factor analysis and ancova models applied to the combined dataset allowed to identify the underlying ecological processes governing the system, and construct conceptual graphic models of the periphyton–environment relationships observed. With the first factor, variability in water quality was due to autotrophic (photosynthesis and nutrient uptake) and heterotrophic (respiration and decomposition) processes affecting water quality in opposite directions. With the second factor, variability was related to decomposition on the bottom and nutrient release into the water column, algae production and sedimentation. The analysis of the relationships between both factors and the growth rates of tilapia and prawn in the different systems allowed a better understanding of the functioning of tilapia–prawn ponds, and indicates that their joint culture is technically feasible and economically viable. Therefore, this technology is recommended for poverty alleviation and nutritional security in rural Bangladesh as well as in other countries of the region.     

Food availability for blackbuck (Antilope cervicapra) at Lal Suhanra Sanctuary,Pakistan

The Blackbuck has suffered rapid decline at the hand of Man during the last half-century, having been exterminated in many areas in which it was formerly plentiful. However, it is said to occur still fairly widely in small populations within its former range in India. In Cholistan Desert in Pakistan ot was indigenous but has disappeared during the last two decades. Where introduced in Texas it is flourishing. Ten Blackbuck were reintroduced from Texas to a small enclosure in the Lal Suhanra Sanctuary, Pakistan, in April 1970, and more stock is expected to be introduced into a near-by larger fenced enclosure of 518·4 ha. Food habits of Blackbuck were studied and the food was estimated in the latter area on 3–8 April 1971. Out of 22 commonly-occuring plant species in the habitat, 19 were eaten. Of these, four or five were favourite food plants of Blackbuck. The quantity of favourite food was estimated and an idea was formed of the order of magnitude of stocking that could be done in this enclosure.     

Dairy cow reproduction under the influence of heat stress

Dairy farming is vulnerable to global warming and climate change. Improving and maintaining conception rates (CRs) have a paramount importance for the profitability of any dairy enterprise. There is an antagonistic relationship between fertility and milk yield, and intensive selection for milk yield has severely deteriorated reproductive efficiency. Irrespective of geography and husbandry, modern dairy cows experience heat stress (HS) effects leading to fertility declines, but it worsens in tropical climates. The threshold of HS experience among modern dairy cow has lowered, leading to decreased thermal comfort zone. Studies show that this threshold is lower for fertility than for lactation. HS abatement and robustness response to lactation yield lead to negative energy balance, and cow's reproductive requirements remain unfulfilled. The adverse effects of HS commence from developing oocyte throughout later stages and its fertilization competence; the oestrus cycle and oestrus behaviour; the embryo development and implantation; on uterine environment; and even extend towards foetal calf. Even cows can become acyclic under the influence of HS. These harmful effects of HS arise due to hyperthermia, oxidative stress and physiological modifications in the body of dairy cows. Proper assessment of HS and efficient cooling of dairy animals irrespective of their stage of life at farm is the immediate strategy to reduce fertility declines. Other long- and short-term mitigation strategies to reduce fertility declines during HS include feeding care, reducing disease and mastitis rates, using semen from cooled bulls, timed artificial inseminations (AI), allied hormonal interventions and use of embryo transfer technology. Ultimate long-term solution should be well-planned breeding for fertility improvement and HS tolerance.     

Crossability of tetraploid and hexaploid wheats with ryes for primary triticale production

Summary Crossability of wheat and rye was investigated during thirteen crop cycles in two contrasting locations to 1) evaluate tetraploid and hexaploid wheat parents in crosses with rye, 2) identify genotypes with high crossability and 3) assess the impact of environment on seed development. The majority of the tetraploid wheats crossed with rye had seed set around 20%, but very low embryo viability. Several wheat genotypes with seed set above 50% were identified. The hexaploid wheats crossed with rye showed poor seed set, but plant recovery was relatively high. The majority of the hexaploid wheats with highest seed set (20–30%) were from China. The results suggest differences in crossability between the rye populations, and wheat species by rye interactions. The crossability of the tetraploid and hexaploid wheats was affected by climate in the two locations.     

Impact of Land Uses,Agrophysical Variables and Altitudinal Gradient on Soil Organic Carbon Concentration of North‐Eastern Himalayan Region of India

In the fragile hilly ecosystem of North‐eastern Himalayan Region (NEHR) of India, interaction of land use change and soil organic carbon (SOC) holds significance in sustaining land productivity. However, because of limited data, the effect of land use on SOC inventory at regional level is poorly quantified. The present study assessed the influence of seven major land uses and agrophysical variables (soil texture, bulk density, annual rainfall and mean temperature) on SOC concentration and stock across altitudinal gradients (6–3,500 masl) of NEHR of India. Results revealed that non‐agricultural land uses (grasslands and forests) registered significantly higher SOC concentration (2·20 to 2·51%) and stock (35·2–42·1 Mg ha⁻¹) compared with agricultural (shifting and settled‐up and lowlands), plantation and horticultural land uses (SOC, 1·44 to 1·63%; stock, 27·4–28·4 Mg ha⁻¹). Principal component analysis exhibited that the variation in SOC concentration among the land uses was mostly contributed by finer fractions of soil separates (silt and clay contents), and altitudinal gradient led variation in climatic variables (rainfall and temperature). Trend analyses depicted that SOC increased with an increase in rainfall and clay content but decreased with mean temperature and soil bulk density. Along the altitudinal gradient (6 to 1,000 masl), an inconsistent increase in silt + clay, annual rainfall, SOC concentration, and stock was also observed. However, beyond 1,000 masl, the corresponding increase was linear. The wide variability in SOC concentration and stock, therefore, resulted from the interaction of land uses, altitudinal gradients, textural gradients and climatic variables Copyright © 2015 John Wiley & Sons, Ltd.     

Genotypic variability in plant water status of French bean under drought stress

Seven genotypes of French bean (Phaseolus vulgaris L.) were evaluated under semi-controlled conditions at the Bangabandhu Sheikh Mujibur Rahman Agricultural University, Bangladesh to analyze genotypic variability in leaf water status under water stress. The plants were grown under two moisture regimes, viz. 80% field capacity (FC) and 50% FC throughout the growing season. The genotypes showed significant variation in water relation traits. Genotypes BB24 and BB43 maintained higher relative water content (RWC), but lower turgid weight/dry weight ratio (TW/DW) and water uptake capacity (WUC). When drought susceptibility index (DSI) among the genotypes was considered, BB24 was found the most tolerant to drought and BB04 was the most susceptible one. A close positive relationship between leaf TW/DW and DSI under drought was recorded (R ² = 0.627). Leaf TW/DW was decreased considerably due to water stress by 10% in genotype BB24 followed by BB43 (13%), and both BARI bushbean-2 and BB04 (19%). Stomatal aperture and whole plant transpiration rate were found minimal in the BB24 and BB43 compared to that of BB04 and BARI bushbean-2. Considering these water relation traits, genotypes BB24 and BB43 may be considered as relatively tolerant to tissue dehydration. The study also revealed that the TW/DW, WUC, stomatal aperture, and whole plant transpiration rate was negatively and significantly associated with yield; however, the RWC was positively correlated with yield under water stress conditions.     

Gibberellin producing Neosartorya sp. CC8 reprograms Chinese cabbage to higher growth

Gibberellins production by soil fungi received little attention, although substantial work has been carried out on other growth promoting aspects of soil borne fungi. We investigated gibberellins production and growth promoting capacity of a novel fungal strain of Neosartorya, which was isolated from the roots of Chinese cabbage (Bassica rapa L. ssp. pekinensis). Fungal culture filtrates (CF) obtained from pure cultures of 16 endophytic fungi were bioassayed on Waito-C, in order to investigate plant growth promoting capacity of these fungi. The fungal isolate CC-8 induced maximum shoot length of Waito-C (13.0 cm) as compared to control treatments. In a separate experiment, the CF of fungus CC-8 significantly promoted plant length and biomass of Chinese cabbage. The fungal CF also increased endogenous bioactive GA₁ and GA₄ contents of Chinese cabbage. Gibberellin analysis of CF of CC-8 showed presence of both physiologically active and non active gibberellins in higher concentrations (GA₁, 1.42 ng/ml; GA₃, 5.93 ng/ml; GA₄, 11.36 ng/ml; GA₇, 3.25 ng/ml; GA₉, 0.79 ng/ml; GA₁₅, 1.18 ng/ml). The culture filtrate of CC-8 produced higher amounts of GA₃, GA₄, GA₇ and GA₉ than wild type Fusarium fujikuroi, a well known gibberellins producing fungus. The fungal isolate CC-8 was later identified as a new strain of Neosartorya species on the basis of traditional and advance molecular techniques.     

Long-term manure application increased soil organic carbon and nitrogen mineralization through accumulation of unprotected and physically protected carbon fractions

Soil organic carbon(SOC) and nitrogen(N) mineralization are important biogeochemical processes associated with soil fertility. These processes are influenced by physically, chemically, and biologically stabilized SOC fractions, the mechanisms of which are not well known. The present study was conducted to evaluate the combined effect of manure and mineral fertilizers on the contents of SOC fractions to promote the mineralization of SOC and N.Treatments included: i) no fertilizer control(CK); ii)...