STATUS AND PROSPECTS OF KAREZ IRRIGATION1

ABSTRACT: The karez is a traditional irrigation water source, consisting of hand-dug horizontal wells, that is still used in parts of South Asia, the Middle East, and North Africa. This paper describes the construction, management, and current problems of karez irrigation systems based on investigations conducted in Baluchistan Province, Pakistan. While karezes have served irrigation needs well in the past, they are now threatened by high costs of labor for construction and maintenance, and by the encroachment of tubewells which lower the water tables on which the karez systems depend. Possible methods for improving karez performance and needs for research are discussed.     

Distinct effects of intrinsic motivation and extrinsic rewards on radical and incremental creativity: The moderating role of goal orientations

Previous studies have investigated the role of intrinsic motivation and extrinsic rewards in enhancing employee creativity. However, the possibility that these motivational factors affect the creativity of different types remains largely unexplored, particularly in the organizational settings. Moreover, the potential that personality traits may moderate the function of these motivational factors toward creativity is another underresearched area. By drawing on the person–situation interaction perspective, we propose that both intrinsic motivation and extrinsic rewards predict creativity but of different types. Thus, we diverge from the view that creativity is a uniform criterion domain by adopting the distinction between radical and incremental creativity. Our empirical analysis of 220 independent employee–supervisor dyads confirmed that intrinsic motivation and extrinsic rewards predict radical and incremental creativity, respectively. Moreover, the effects of intrinsic motivation on radical and incremental creativity are more positive for employees with higher learning goal orientation. By contrast, the effect of extrinsic rewards on incremental creativity is more positive for employees with higher performance goal orientation. This study offers elaborate and nuanced perspectives and insights into the role of different motivational processes in the development of different types of creativity.     

Economic valuation of Shadegan International Wetland,Iran: notes for conservation

Wetlands are among the most productive ecosystems on the earth. They produce various market and non-market goods and services, which have a significant role in human welfare. Despite the great opportunities from sustainable development, wetlands all over the world are under serious threat from a diverse range of non-sustainable activities. One of the major reasons for excessive depletion and the conversion of wetland resources is due to underestimating the non-market values of wetlands during development decisions. Shadegan International Wetland (SIW) in southern Iran is one of these wetland areas that is threatened by undervaluation and overexploitation from commercial activities. This study utilizes the contingent valuation method to estimate the economic benefits of SIW from the view point of peoples’ willingness to pay (WTP). The logit model was defined based on dichotomous choice to measure individuals’ WTP. The estimated mean WTP was US$ 1.74 per household as a onetime donation. This study concludes that the benefits of SIW to society could encourage managers to set priorities to ensure that the health of the ecosystem, its integrity, and its uniqueness would be conserved in a proper manner.     

Nexus between corruption and regional Environmental Kuznets Curve: the case of South Asian countries

This study attempts to investigate the presence of a regional Environmental Kuznets Curve (EKC) in selected South Asian countries, namely, Pakistan, India, Bangladesh, and Sri Lanka for the period 1984–2008. In addition, it also intends to inspect the impact of corruption on environmental degradation in this region. The Fixed Effect results confirm the existence of the regional EKC in these countries. Furthermore, the results indicate that corruption do affect environment in the manner that it delays the turning point in EKC. It is found that, in the presence of corruption, the per capita GDP at the turning point is USD 998, which is USD 128 higher from the value that would have been in the absence of corruption. Based on these results, the study suggests appropriate policy measures.     

Pesticides exposure in Pakistan: a review

This is the first systematic review of studies done since 1960, and to give an integrated picture of pesticides exposure to humans, animals, plants, waters, soils/sediments, atmosphere etc. in Pakistan. Authors have extracted data from different departments, published literature in research journals and National reports. Although the wide-spread usage of pesticides in Pakistan has controlled the pests, but like other countries, it has started causing environmental problems in the area. In some areas of Punjab and Sindh groundwater has been found contaminated and is constantly being under the process of contamination due to pesticide use. There is considerable evidence that farmers have overused and misused pesticides especially in cotton-growing areas. It is evident from the biological monitoring studies that farmers are at higher risk for acute and chronic health effects associated with pesticides due to occupational exposure. Furthermore, the intensive use of pesticides (higher sprays more than the recommended dose) in cotton areas involves a special risk for the field workers, pickers, and of an unacceptable residue concentration in cottonseed oil and cakes. The authors have also discussed the merits and demerits of different studies. The review will set the future course of action of different studies on pesticide exposure in Pakistan. Data limitations are still the major obstacle towards establishing clear environmental trends in Pakistan. The authors suggest that a reliable monitoring, assessment and reporting procedures shall be implemented in accordance with appropriate environmental policies, laws and regulations in order to minimize the pesticides exposure.     

Mathematical modeling of sustainable development goals of India agenda 2030: a Neutrosophic programming approach

Environment, Development and Sustainability - Since 2015, the United Nations sustainable development goals (SDGs) agenda 2030 has been designed with 17 goals, 169 targets, and 232 unique indicators...     

Optimizing different adaptive strategies by using crop growth modeling under IPCC climate change scenarios for sustainable wheat production

Environment, Development and Sustainability - Crop production is highly sensitive to climate. It is affected by long-term trends in average rainfall and temperature, inter-annual climate...     

Foliar uptake of arsenic nanoparticles by spinach: an assessment of physiological and human health risk implications

Atmospheric contamination by heavy metal(loid)–enriched particulate matter (metal-PM) is highly topical these days because of its high persistence, toxic nature, and health risks. Globally, foliar uptake of metal(loid)s occurs for vegetables/crops grown in the vicinity of industrial or urban areas with a metal-PM-contaminated atmosphere. The current study evaluated the foliar uptake of arsenic (As), accumulation of As in different plant organs, its toxicity (in terms of ROS generation, chlorophyll degradation, and lipid peroxidation), and its defensive mechanism (antioxidant enzymes) in spinach (Spinacia oleracea) after foliar application of As in the form of nanoparticles (As-NPs). The As-NPs were prepared using a chemical method. Results indicate that spinach can absorb As via foliar pathways (0.50 to 0.73 mg/kg in leaves) and can translocate it towards root tissues (0.35 to 0.68 mg/kg). However, health risk assessment parameters showed that the As level in the edible parts of spinach was below the critical limit (hazard quotient <?1). Despite low tissue level, As-NP exposure caused phytotoxicity in terms of a decrease in plant dry biomass (up to 84%) and pigment contents (up to 38%). Furthermore, several-fold higher activities of antioxidant enzymes were observed under metal stress than control. However, no significant variation was observed in the level of hydrogen peroxide (H₂O₂), which can be its possible transformation to other forms of reactive oxygen species (ROS). It is proposed that As can be absorbed by spinach via foliar pathway and then disturbs the plant metabolism. Therefore, air quality needs to be considered and monitored continuously for the human health risk assessment and quality of vegetables cultivated on polluted soils (roadside and industrial vicinity).

?

     

Self-healing concrete for sustainable buildings. A review

Environmental Chemistry Letters - A total of 12 billion tons of concrete materials are produced annually, about 2 tons per person. More sustainable buildings are thus needed to decrease the carbon...     

Assessment of cobalt in wheat grains as affected by diverse fertilizers: implications for public health

Environmental Science and Pollution Research - Present study was conducted to check the heavy metal content in wheat treated with municipal solid waste, Although municipal solid waste was enriched...