Vol. 9, No. 1 (2021): Regular Issue

Heat pumps are mechanical devices that can be used for the sustainable generation of heating and cooling energy. However their construction generates also environmental burdens. The aim of this manuscript is the identification of the environmental hot spots of a air/water heat pump via means of life cycle assessment. Inventory data were collected by primary sources. The results indicate that the case of the heat pump, made of stainless steel, is the dominant contributor to the environmental impacts generated by the construction of the heat pump. Moreover, the main impact category affected by the heat pump components is that of human toxicity.

The research aims to study the dynamics of soil fertility of agricultural lands of the Northern forest-steppe. For this, in the process of field surveys, soil sections were laid, a description of the morphological structure with the selection of soil samples by genetic horizons. The field stage is carried out by route inspection, according to the coordinates of the previously designated points; sections are laid out with a description of all genetic horizons for the subsequent determination of the name of the soil. Based on the results of field, a digital soil map of agricultural lands was compiled.

Recently, many studies have highlighted the role of urban and peri-urban forests in mitigating environmental pollution and maintaining human quality of life by integrating the concepts of ecosystem services into forest management strategy. To increase the social acceptance and to reduce the conflicts between users, citizens' preferences towards ecosystem services should be included in the decision-making process. In the present study, a structured questionnaire was administered to a sample of 180 citizens and 50 forest managers of the Tlemcen peri-urban forest (Algeria). The collected data was processed to show convergent and different preferences between forest managers and citizens towards the main categories of ecosystem services -- provisioning, regulating, supporting, and cultural services -- provided by the Tlemcen peri-urban forest. The results show that for both groups of respondents the three most important ecosystem services are: tourism and recreation (cultural services), soil erosion protection (regulating services), and biodiversity conservation (supporting services). Conversely, provisioning services (wood and non-wood forest products) are considered marginal by the two groups of respondents. These results are in line with international literature, which highlights in post-modern society an increase in importance of intrinsic values of nature at the expense of instrumental values.

As the government has begun to promote the sharing economy and green travel, shared bikes have wide spread in many cities in China. Bike sharing system (BSS) facilitates people's travel, relieves traffic jams, and mitigates carbon emissions. In this research, a basic method is proposed to measure the carbon emission mitigation of dock-less BSS from the perspective of life cycle analysis (LCA). The method is applied in a typical city of China (i.e., the city of Beijing). The carbon emissions of six models of shared bikes in Beijing are calculated in this paper. The results indicate that: (a) the use process of dock-less BSS has mitigated carbon emissions in the central district of Beijing (9.23 Mt CO$_{\text{2-eq}}$ in 2016 and 9.26 Mt CO$_{\text{2-eq}}$ in 2017); (b) in consideration of all life cycle processes of BSS, the carbon emissions actually has risen with the best scenario of 10% substitute rate (i.e., 33.2 Mt CO$_{\text{2-eq}}$ in 2016 and 80.9 Mt CO$_{\text{2-eq}}$ in 2017); (c) the carbon mitigation effect of BSS is closely related to the processes of production, maintenance and rebalancing. Finally, to promote the effect of carbon mitigation, it is necessary to control the number of shared bikes and increase their utilization rate.

Analyzing the water quality status is one of the most important issues to control the pollution discharged to the river. This helps to obtain the effective environmental management. However, the conventional water quality indices cannot accurately indicate the water quality status, particularly in the presence of the various water quality parameters. In this study 15, water quality parameters of Karun River were categorized based on the similar variation pattern by Self-Organizing Map (SOM) for a 6-year period between 2013 and 2018. Data were then clustered using the k-means nonhierarchical algorithm for determination of the spatio-seasonal pattern of Karun River's water quality and discrimination of the sources of water pollution all along Karun River catchment. The results indicated the dissimilar variation patterns of some water quality parameters which were might due to the different sources of pollutions around the Karun River catchment. Moreover, data clustering by k-means specified 5 different groups collected data. Spatio-seasonal assessment identified the critical stations in the Karun River during a 6-year period. The result of the applied methodology showed an integration of SOM and k-means algorithms gives an insight into the similarities of water quality parameters and analysis of the water quality conditions in critical locations. Therefore, it can be used as a tool for efficient decision making in environmental management.

To assess the effectiveness of the four restoration techniques (one mono-technology, three combined technologies) on a degraded meadow swamp in Three-river Source Region, we developed a Biology-Environment-Service assessment framework that incorporates 12 indicators from plant, soil to ecosystem services. Two years (2018 and 2019) field monitoring and experimental data revealed that a good restoration effect achieved by the ecological restoration project. The average comprehensive restoration index (CRI)of four restoration sites are, respectively, 0.68, 0.89, 0.71 and 0.84, belonging to a level of GOOD or EXCELLENT. Restoration effect of ensemble restoration technologies is about 4.4%-30% better than that of single fencing. The vegetation restoration was about 2.8 times faster than that of soil and ecosystem services under the same restoration technology during research periods. Restoration effect presented significant difference in respond to various restoration techniques. A combination restoration measue (Fencing + water reservation + reseeding) is recommended as a potential effective restoration method for early stage of alpine wetland restoration.

Despite being still little explored, tariff policies have a large potential to foster more efficient management of water resources, mainly in scarcity regions. Therefore, this paper proposes a model of water scarcity pricing (WSP), based on the storage average monthly data and historical average data of the volume of the reservoir between January 1996 and December 2017, besides the fixation coefficients of adjustments for each operational range and zones of accumulation of reservoir Epit\'{a}cio Pessoa. The simulated results point to an annual percentage of significant reductions in water demand, mainly in years of low levels of water stocks in the reservoir, for example, 8% in the years 1998-2001 and almost 13% for 2016-2017. Moreover, it was also verified, through the water budget boundary (percentage of water bill over average residential income), that scarcity prices are accepted as socially just, because this rate is below the affordable index of 5%, as recommended by the World Bank. The WSP model has been created for the Water and Sewage Company that operates in Campina Grande, but might be easily implemented in all other regions that are supplied by surface reservoirs and operate under similar water scarcity conditions.