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Temporary and permanent decline in the productive capacity of the land due to natural and human-induced activities such as soil erosion, changing cropping practices and less use of organic matter (OM) has been the greatest challenge faced by mankind in recent years, particularly in the hills and mountains of Nepal. Hence, the purpose of this paper is to examine the effectiveness of sustainable soil management practices to mitigate desertification process in the hills of Nepal.

Promotion of sustainable soil management (SSM) practices through a decentralised agriculture extension approach by involving all the stakeholders in a participatory way.

SSM practices mainly: OM management, fodder and forage promotion, increased biomass production systems, integrated plant nutrition systems, and bioengineering for soil and water conservation are identified as the most appropriate and relevant technologies in mitigating the desertification process without deteriorating land quality, particularly conserving the top-soils effectively and efficiently in the hills and mountains of the country.

This research is focus on the overall effect of SSM practices due to time and budget constraints. There is scope for doing research on the different aspects of SSM practices and the extent of their effect on different soil parameters (chemical, biological and physical).

SSM interventions clearly indicated that there is significant impact in increasing soil fertility, conserving fertile top-soils and mitigating physical, chemical and biologic desertification processes. These are possible through maintaining and improving the soil organic matter, which is the most important indicator for soil health. SSM practices have resulted in an increase of up to 30 per cent in crop yield compared to yields without SSM practices. This might be due to the improvement in SOC which improves soil texture, increases nutrient supply from organic source and conserves water quality, thus, improving soil quality.

This has created awareness among farmers. Hence, farmers are mitigating pH through increased use of organic manures, where there is less availability of agriculture lime and they are far from road access.

SSM practices significantly contributes to combat soil desertification in the hills of Nepal.

This paper aims to construct a simplified distributed hydrological model based on the surveyed watershed soil properties database.

The new established model requires fewer parameters to be adjusted than needed by former hydrological models. However, the achieved stream-flow simulation results are similar and comparable to the classic hydrological models, such as the Xinanjiang model and the TOPMODEL.

Good results show that the discharge and the top surface soil moisture can be simultaneously simulated, and that is the exclusive character of this new model. The stream-flow simulation results from two moderate hydrological watershed models show that the daily stream-flow simulation achieved the classic hydrological results shown in the TOPMODEL and Xinanjiang model. The soil moisture validation results show that the modeled watershed scale surface soil moisture has general agreement with the obtained measurements, with a root-mean-square error (RMSE) value of 0.04 (m³/m³) for one of the one-measurement sites and an averaged RMSE of 0.08 (m³/m³) over all measurements.

In this paper, a new simplified distributed hydrological model was constructed.

The evolution in developed countries has taken a role in global warming and natural disasters such as flash flood, El-Nino, earthquake and groundwater contamination. The underground storage tank leakage problems and spillage of hydrocarbon liquid leading to the contamination of non-aqueous phase liquids (NAPLs) into the groundwater could reduce the quality of groundwater. This chapter is intended to investigate the behaviour and the pattern of NAPL migrations in double-porosity soil under vibration and intact conditions. The experimental model is developed by using kaolin soil type S300 and toluene as NAPLs. The kaolin soil was mixed with 25% of moisture content to produce kaolin granules in the soil column and vibrate under 0.98 Hz of frequency within 60 seconds. As a result, both specimen liquids completely migrated to the bottom of soil column: sample 1 has higher permeability compared to sample 2. This is due to the fracture in double-porosity soil under vibration effect and loosened the soil structure in sample 1 compared to good intact soil sample 2 with stronger and compact soil structure. In conclusion, this study proves that the dangerous hydrocarbon NAPL migration in fractured double-porosity soil has very harmful effect on the environment and groundwater resources.

Problems addressed, in reporting from relevant sources, include population pressure, subsistence agriculture, rural poverty, natural resource depletion with emphasis on deforestation, land degradation, decline in productivity, resource rich/urban biased policies, and gender disparities. Compounded, these problems, which if isolated already pose tough challenges, seem to form an insurmountable barrier in the development path toward sustainable agriculture. Efforts made so far have had impacts below expectations. Recognizing biodiversity as the key stepping stone, the proposition is outlined that prospects will be improved significantly through the recognition of the great potential of diversity in human and technical resources as well. Needed are in‐depth research and thorough multidimensional analyses, to formulate an alternative strategy geared to mobilize the synergy yet hidden in the potential of the three‐pronged resource diversity.

The use of digital-models to communicate civil-engineering design continues to generate debate; this pilot-work reviews technology uptake towards data repurposing and assesses digital (vs traditional) design-preparation timelines and fees for infrastructure. The paper aims to discuss these issues.

Extending (building-information-modelling) literature, distribution-impact is investigated across: quality-management, technical-applications and contractual-liability. Project case-study scenarios were developed and validated with resultant modelling-application timeline/fees examined, in conjunction with qualitative semi-structured interviews with 11 prominent stakeholder companies.

Results generated to explore digital-model data-distribution/usage identify: an 8 per cent time/efficiency improvement at the design-phase, and a noteworthy cost-saving of 0.7 per cent overall. Fragmented opinion regarding modelling utilisation exists across supply-chains, with concerns over liability, quality-management and, the lack of Australian-Standard contract-clause(s) dealing directly with digital-model document hierarchy/clarification/reuse.

Representing a small-scale/snapshot industrial-study, findings suggest that (model-distribution) must emphasise checking-procedures within quality-systems and, seek precedence clarification for dimensioned documentation. Similarly, training in specific file-formatting (digital-model-addenda) techniques, CAD-file/hard-copy continuity, and digital-visualisation software, can better regulate model dissemination/reuse. Time/cost savings through digital-model data-distribution in civil-engineering contracts are available to enhance provision of society’s infrastructure.

This work extends knowledge of 3D-model distribution for roads/earthworks/drainage, and presents empirical evidence that (alongside appropriate consideration of general-conditions-of-contract and specific training to address revision-document continuity), industry may achieve tangible benefits from digital-model data as a means to communicate civil-engineering design.

There is a growing concern that contractors can be motivated for environmental protection through effective fund allocation and proper payment mechanisms. However, an in-depth analysis of environmental hazard-controlling methods and related payments to the contractor in road construction in Sri Lanka is not much popular among the extant literature. Thus, the purpose of this paper is to explore different payment mechanisms that are being used with environmental hazard-controlling methods, to achieve better control in such hazards in Sri Lankan road construction projects.

This research was approached through a mixed research method. Initially, hazard-controlling methods and relative payment mechanisms for the contractor were identified through three exploratory case studies using interviews, observations and document survey. Next, the relative effectiveness of payment mechanisms for contractors for better environmental hazard controlling was identified through a questionnaire survey with a sample of 45 professionals involved in 15 road construction projects.

Based on the findings, a comprehensive list of environmental hazard-controlling methods was derived. Furthermore, four types of payment mechanisms were identified: (A)-payments, where a unit price was assigned; (B)-payments, where a provisional sum was established in the contract; (C)-payments, where fixed amounts (lump sums) were assigned in the contract and (D)-payments made along with some main work item in the contract. Relative effectiveness of these four mechanisms for better control of environmental hazards was varied for each hazard-controlling method being practiced in a road construction project.

These findings would be more beneficial for consultants, project managers, bidders and estimators in the pre-contract stage. This is by identifying cost items for environmental hazard controlling and selecting relatively more effective payment mechanisms to motivate contractors for better control of environmental hazards during project execution.

There has been a general promotion of small and medium sized dams as the solution to supply water for domestic, sanitation and other livelihood purposes in the less industrialised countries of the world. This paper aims to communicate and share ideas and experiences with policy makers and other engineering practitioners in issues related to the sedimentation of, and the development of small and medium sized dams so that relevant issues are taken into account in the planning, design and implementation of such small and medium sized dams.

This paper, which is a viewpoint, utilises the findings of various research work carried out in Zimbabwe and findings from other regional and international literature as a basis for discussion and arriving at some engineering and other developmental policy recommendations. The research work utilised and analysed in this paper is based on actual field work carried out by others as cited.

The paper concludes that the following policy and technical issues should always be borne in mind in the promotion of small and medium sized dams: the predicted increase in rainfall intensities due to climate change/variability requires the review of existing small and medium sized dam spillway capacity designs; an increase in the minimum storage ratios of small and medium sized dams should be made from the current recommended 0.1‐0.3; further research work is required to validate the postulation that rainfall intensities are increasing due to the effects of climate change/variability resulting in increased sedimentation of reservoirs; whilst sediments are required for ecosystem sustenance, they can also be viewed as a pollutant in respect of certain other human water supply needs; do not build small dams on large catchments as such small dams will silt‐up quickly and thereafter pose challenges in the management and disposal of the accumulated sediments and nutrients when decommissioning/rehabilitating them; every dam site, irrespective of the resultant dam size, should be developed to its maximum potential in respect of the dam site's water yield and/or prevailing topography; WHO predicts that road traffic injuries will rise to become the fifth leading cause of death by 2030. The “vulnerable road users” and/or their estates should also receive like attention and timely compensation benefits as advocated for the large dam's “disadvantaged and vulnerable” people.

Every year, about 1 per cent of the world's reservoir capacities are lost to sedimentation. Most researchers postulate that an increase in the intensity of rainfall due to climate change/variability is imminent and will result in increased sediment loads with resultant negative impacts on dam reservoir life‐spans and usefulness. This paper discusses the advantages, disadvantages and efficiency of small and medium sized dams in satisfying the various beneficiary needs in the less industrialised countries of the world. The technical issues that have to be considered in the design and construction of such small and medium sized dams in order to minimise the negative impacts of sedimentation in their development are also presented and discussed. The opinions and conclusions drawn in the viewpoint are those of the author.

This paper reviews the work of E. F. Schumacher, who was a great economist, environmentalist and alternative thinker. He was a seminal influence for the creation of many organisations in the UK that are thriving and increasingly relevant as we appreciate the value of living local, personal, simple, organic, spiritual, integrated and appropriately scaled lives. His influence is considered through four reflective principles (appropriateness, non-violence, spirituality and simplification) and three active ones (local action, simplicity and the integration of the inner and the outer).The consequences of his philosophy are briefly considered in the world of accountancy where mechanisms to include environmental and social factors are often poor. The rise of so-called ‘conscience economics’ may provide ways to redress this imbalance. Can we discover new instruments to complement philanthropy, fair trade, offsetting and other ways to pay the full externalities that are traditionally ignored?

Improved current distribution from suitably selected deep groundbeds may be achieved as compared with conventional surface groundbeds. This is of considerable importance in municipal areas where interference problems with other sub‐soil structures are inevitable. More particularly so where comparatively high current densities are required for the protection of pre‐stressed concrete pipes. Cathodic protection of pre‐stressed concrete pipes poses problems utterly different from those met in the practice of cathodic protection of coated steel pipes and, in view of lack of sufficient experience, protective criteria have yet to be established.

Protects process equipment from aggressive chemical attack. A new type of protective coating based on Du Pont Teflon fluoropolymer is said to extend service life and cut maintenance needs for chemical process equipment exposed to strong corrosives and oxidants, even at high temperatures.