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991.
Fast economic and social changes in recent years in China have brought massive expansion, redevelopment, and restructuring of cities. These changes offer cities the opportunity to improve environmental quality through urban green spaces (UGSs) and to address the challenges of meeting community aspirations. This study explored peoples’ minds concerning UGSs in Guangzhou city in south China in relation to the following: (1) knowledge and perception of 25 ecosystem services and 8 negative impacts; (2) attitude toward site condition and management; (3) expectation of landscape design; and (4) preference ranking of venues. A questionnaire was designed to solicit opinions from 340 respondents randomly chosen from residents living in the study area. The results indicated widespread recognition of ecosystem services and strong support of UGS programs. Negative responses were weakly expressed. Amelioration of urban microclimate and environmental quality were emphasized. Environmental functions stressed in publicity programs, together with aggravating environmental problems in the city, tended to focus respondents’ attention on UGS benefits. Wildlife habitat, species conservation and other natural ecosystem services drew limited concerns. Awareness of economic benefits was very low. Visual-landscape contributions with strong preference for naturalistic design and recreational benefits were highlighted. Compared with other countries, Guangzhou residents were characterized by visual–scenic–recreation orientation and pragmatic–utilitarian perception of UGSs, reflecting underlying differences in the understanding of inherent ecosystem services of green spaces. Relevant UGS policies and practices could adopt the approaches of market survey, citizen participation, and precision planning in order to meet increasingly mature and refined demands. Citizens’ understanding of high-order ecosystem services could be enhanced to encourage appreciation of nature and their associated benefits.  相似文献   
992.
西安作为汾渭平原地区最大的城市,大气颗粒物污染形势严峻.2017年夏季期间,在西安市浐灞生态园区运用气溶胶化学组分监测仪,对大气亚微米颗粒物中的非难挥发性组分(NR-PM1)进行了在线监测.观测期间NR-PM1的平均质量浓度为(30.1?±?15.4)μg???m?3.其中有机物含量最高,占NR-PM1总质量浓度的63...  相似文献   
993.
Data management is becoming increasingly simple and complex at the same time. The challenge is to effectively use the increasing number of tools available to manage increasing amounts of environmental information for purposes of data capture, analysis, display, sharing and storage. Government is no longer the main collector and provider of data. Community groups possess vast amounts of data collected through daily work of monitoring the environment in their local community. The chief concerns are data access, sharing, integrity and comparability. The capacity of groups to sustain data management is the key to making the sharing possible. The Southeast Environmental Association has been working with Environment Canada to develop a community, on-line database that will be linked to other geo-spatial data sets to allow instant access to geo-referenced data.  相似文献   
994.
People are relaxed (satisfied or well-off) in what is described as comfortable climatic conditions. In such conditions, a person’s energy balance is not disturbed because of stresses from extreme heat or cold. Bioclimatic structure has been well researched and should be a consideration in the planning process for arranging comfortable spaces. It represents the understanding that energy balance is one of the basic elements of a sustainable landscape design. The goals of this study have been to create ideal places for human thermal comfort and to advance objectives focused on the importance of sustainable and ecological landscape planning and design work, along with their accompanying economic benefits. In this study, which focuses on the climate of the Province of Aydin, the most suitable areas for bioclimatic comfort have been identified. The climate values for the Aydin Province have been taken from a total of 22 meteorological stations. Stations at altitudes ranging from 11 to 871 m were used to note the climate changes that occurred. The average temperature, relative humidity, and wind speed from each station, including data collected using Geographic Information System (GIS) software, were transferred. GIS maps were then created from the imported data, and areas of optimal comfort around the city of Aydin were determined. The results show the range that is suitable for a bioclimatic comfort zone in Aydin. The bioclimatic comfort range was determined to be roughly 17 °C for Aydin, and the city of Aydin demonstrated a comfort range between 14 and 19 °C. As a result, the city of Aydin was shown to be a suitable area for bioclimatic comfort.  相似文献   
995.
The present research focuses on estimating forest area change with respect to the ongoing forest land conversion. The study tests the hypothesis that forest land is being converted to the selected land use categories with high growth tendency and controlling deforestation rate to its half of the present level would significantly improve the land cover under forest. The rate of forest land conversion to other land use categories is analyzed and then compared with the total area expanded under three land use classes. We used Systems dynamic modeling approach to estimate forest area by simulating forest land conversion in Pakistan, projecting to 2030. The results show that rangeland, built-up area and cultivated land have increased over time; growth rate of built-up area (9%) is highest followed by rangeland area (1.7%) and cultivated area (0.3%), respectively; rangeland is the dominant category in terms of area expanded (0.74 m. ha). Sensitivity analysis showed that reducing deforestation rate to half of the past level of 1% could not significantly improve forest area; therefore, it is suggested that controlling deforestation alone is not an effective strategy unless drastic measures, e.g., demarcation of forest boundaries, land use control policy and afforestation campaign would be started in the country.  相似文献   
996.
The soil characteristics are critical for crop health and its yield and therefore for agriculture. The soil properties are spatially variable and therefore soil resources should be managed as per location-specific requirements. An integrated spatial analysis of the soil resources of Mewat district was conducted to identify the soil resource management zones to develop site-specific soil management plan which might lead to sustained and enhanced crop yield. Spatial analysis of soil resources was conducted by modeling soil fertility and erosion which determines the crop productivity in the region. Soil fertility of the region was modeled using weighted overlay approach using 10 soil parameters, namely nitrogen, phosphorus, potassium, sulfur, iron, zinc, manganese, organic carbon, electrical conductivity, and pH. Each parameter was assigned weights based on their relative importance to agricultural productivity. The modeled soil fertility was classified into three fertility zones, low, medium, and high. Soil fertility was found to be low to moderate in 65% of the area, largely because of the low nitrogen, soil organic carbon, phosphorus concentration, and excessive salinity. Soil erosion was modeled using the universal soil loss equation (USLE) model by estimating rainfall erosivity factor (R), the soil erodibility factor (K), the topographic factors (L and S), cropping factor (C), and the conservation practice factor (P). Soil erosion problems were limited to areas having high elevation with barren land and areas with minimal management practices. The severity of soil erosion was found high in 15% of the region, while the remaining 85% showed low to moderate erosion. Soil fertility and erosion were integrated using the multivariate clustering method to identify soil management zones. The region was delineated into three soil management zones. Zone I (29%) which covers majorly Tarou block, was characterized by high soil fertility and low soil erosion. Zone II (18%) with medium soil fertility and high erosion covers villages of Taoru, Nuh, Nagina, FP Jhirka, and Punhana, which are located in the foothills of Aravalli ranges. Zone III represents the major part of the region, covering Nuh, Nagina, and FP Jhirka blocks (54%) with low soil fertility and erosion conditions. Thus, within the study area, the soil management domains are spatially variable in terms of fertility and soil erosion, and thus zone-specific soil management measures are required to improve the soil condition in order to sustain and improve agriculture production. The study would help the policy makers to design site-specific planning for identified soil resource management zones.  相似文献   
997.
Provision of drinking water is considered to be an essential public service. Ensuring adequate water supply remains a challenge in Indian cities that are experiencing rapid growth and often exhibit a mismatch between increasing demands and inadequate supply infrastructure. This study quantifies the existing inequality in water supply within Indian cities through Lorenz curve, Gini coefficient as well as Theil indices. Two types of Theil indices are estimated to gain different perspectives: water supply and population-weighted. Both the Theil indices are disaggregated, according to economic and regional categorisation of the cities, to explore the within- and between-group inequality. The water supply and population-weighted Theil indices provide different outlook of the inequality amongst the cities. But the population-weighted index is often better and pragmatic. Further, the inequality in access to tap water in India is studied by estimating modified Lorenz curves and Theil indices. Again, the Theil indices are decomposed into within and between components according to economic and regional grouping of states. The results suggest that there is disparity in supply of water in India, and infrastructure has to be boosted to meet the growing demand. This study is a step towards quantification of water supply inequality. The approach used in the study can contribute to monitoring of water supply equity as well as in formulating sustainable and equitable water policies.  相似文献   
998.
This study investigates consequences of future changes to the provision of ecosystem services (ES) in the Romanian Carpathians. Two 2040 forest management scenarios were compared, using two indicators to describe the gains and losses of ES. Changes in landslide regulation potential were defined as changes to landslide susceptibility. High nature value grasslands characterized biodiversity support. The business as usual scenario results in a 8% lower loss of landslide regulation potential compared to the alternative scenario. It also results in a 29% higher regional net gain of landslide regulation potential. Both scenarios result in the loss of biodiversity support due to their prevalent transition of forest expansion. This type of information is crucial for informing decision makers on the locations of potential gains and losses of future development.  相似文献   
999.
A new composite has been developed from natural rubber and chrome-tanned leather waste for use in footwear and textile industries. The contribution of this material to environmental quality and sustained development should be highligh because chrome tanned leather wastes, a major environmental problem, can be recycled. However, the safety of this new material for human use is questionable, as it is already well reported in the literature that chromium, particularly in its hexavalent oxidation state, can be genotoxic and carcinogenic to living beings. Thus, the aim of this study was to evaluate in vitro biocompatibility of this composite material for possible use in the footwear and textile industries, through cytotoxicity, cell adhesion, and genotoxicity tests. Inductively coupled plasma optical emission spectrometry (ICP-OES) was used to measure both concentrations of total and hexavalent chromium. Based on the findings, it was concluded that the composite exhibits low levels of cytotoxicity and genotoxicity, and possesses favorable properties for initial cell adhesion. Furthermore, it was verified that the composites released low concentrations of chromium and that the predominant species released would be trivalent chromium. The results of the present study open the possibility of the incorporation of solid residues of tanned leather into chromium without necessarily the chromium contained in these residues influences the toxicity and genotoxicity of this new material.  相似文献   
1000.
Environmental literacy is a key concept to promote individual behavioral changes toward a more sustainable lifestyle to consciously react to environmental challenges such as climate change. Promoting knowledge, attitudes and behaviors provides a reasonable basis to prepare adolescents for their future. A recently proposed environmental literacy model comprises three-dimensional knowledge, environmental attitudes and pro-environmental behavior. The present study applies this model by implementing an intervention focusing on tropical rainforests and climate change in a botanical garden, combining student-centered activities with self-dependent learning. Data from 283 10th graders quantify individual knowledge, attitudes and behavior scores. Knowledge acquisition, a positive development of the Inclusion of Nature in One's Self concept and increasing pro-environmental behavior intentions were found by comparing an intervention group with a test–retest group. In conclusion, our botanical garden’s intervention evidently furthered appreciative tendencies and even encouraged environmental literacy.  相似文献   
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