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Trace element mobility in a contaminated soil two years after field-amendment with a greenwaste compost mulch
2010
Clemente, Rafael | Hartley, William | Riby, Philip | Dickinson, Nicholas M. | Lepp, N. W. (Nicholas W)
Application of greenwaste compost to brownfield land is increasingly common in soil and landscape restoration. Previous studies have demonstrated both beneficial and detrimental effects of this material on trace element mobility. A pot experiment with homogenised soil/compost investigated distribution and mobility of trace elements, two years after application of greenwaste compost mulch to shallow soils overlying a former alkali-works contaminated with Pb, Cu and As (∼900, 200 and 500 mg kg−1, respectively). Compost mulch increased organic carbon and Fe in soil pore water, which in turn increased As and Sb mobilization; this enhanced uptake by lettuce and sunflower. A very small proportion of the total soil trace element pool was in readily-exchangeable form (<0.01% As, <0.001% other trace elements), but the effect of compost on behaviour of metals was variable and ambiguous. It is concluded that greenwaste compost should be applied with caution to multi-element contaminated soils.
اظهر المزيد [+] اقل [-]Beach landscape management as a sustainable tourism resource in Fernando de Noronha Island (Brazil)
2020
Cristiano, Samanta da Costa | Rockett, Gabriela Camboim | Portz, Luana Carla | Souza Filho, José Rodrigues de
The Coastal Scenery Evaluation System was used to analyze the landscape of touristic beaches at the Fernando de Noronha Archipelago, using a checklist with 26 physical and human parameters. The beaches are divided into classes ranging from 1 (extremely attractive natural site) to 5 (unattractive urban areas). The data reflects the natural and anthropogenic characteristics of the coastal Noronha scenery, which have international relevance and are between classes 1–4. Class 3 and 4 beaches are associated with anthropogenic factors/parameters. Seasonal sedimentary stock variation has also contributed to the differences in classes between the seasons at some beaches. The results of this study are useful to create new perspectives for sustainable development based on the singularities of this touristic resource – the landscape. The Fernando de Noronha Archipelago depends on its landscapes for tourism. Therefore, government policies should seek the sustainable management of its beaches, so as to ensure the protection of natural and cultural resources.
اظهر المزيد [+] اقل [-]Characterization and mapping of enset-based home-garden agroforestry for sustainable landscape management of the Gurage socioecological landscape in Ethiopia
2022
Developing strategies that counter the ongoing homogenization trends of home-garden agroforestry systems is required to maintain diversity and sustainability. This study aimed to map and characterize traditional enset-based home-garden agroforestry for managing sustainability in the Gurage socioecological landscape in Ethiopia. We generated plots and land use land cover (LULC) spatial data from orthophotomosaic and collected household survey data of the field. Five home-garden types were identified explicitly through integrating the home-garden composition, functional structure, and agroecological zones. Most home-garden types had similar horizontal functional structures in which perennial crops were planted close to homesteads, annual crops grew in outer fields, and woodlots were located at the end of the parcel. Diverse woody species, crop varieties, and plot sizes were identified in individual household parcels, and these varied across the home-garden types. Enset-based home-garden agroforestry production has been declining in the Ethiopian landscape because of socioeconomic changes and a lack of technological inputs. These challenges may compromise the community’s food security with loss of the product diversity provided by the home-garden system. Thus, technological adoptions and scaling up of agroforestry practices according to the home-garden types are necessary for the continue provision of multiple contributions. This study demonstrated site-specific spatial characterization of the agroforestry systems by considering a holistic approach to reduce the local challenges and support the development of sustainable landscape management in an altering socioecological landscape.
اظهر المزيد [+] اقل [-]Optimal control of nonpoint source pollution in the Bahe River Basin, Northwest China, based on the SWAT model
2021
Li, Shu | Li, Jiake | Xia, Jun | Hao, Gairui
This study conducts in the Bahe River Basin, an agricultural basin in Northwest China. We use the Soil and Water Assessment Tool (SWAT) model to identify the spatial distribution characteristics of non-point source (NPS) pollution and determine the critical source areas (CSA). Then the relationship between landscape pattern and NPS pollution is analyzed by spearman correlation analysis and redundancy analysis (RDA). On this basis, we set up eight landscape management practices in the CSA and evaluate their reduction effects on NPS pollution loads. The results show that the spatial distribution of nitrogen and phosphorus loss intensity has a certain correlation with rainfall and runoff, and the correlation between phosphorus loss intensity and sediment loss intensity is more significant. The NPS pollution load is closely related to the landscape pattern of the river basin, and is affected by the fragmentation, aggregation and complexity of the landscape. Farmland, forest land, and grassland are the main landscape components of the river basin. Farmland is the main source of NPS pollution, whereas forest land and grassland can effectively inhibit the output of NPS pollution, and the reduction effect of forest land is significantly better than that of grassland. The largest patch index (LPI), landscape shape index (LSI), patch density (PD) are the main landscape factors that affect the output of NPS pollution load. Among all the scenarios, the reduction effect of returning farmland to forest land in slopes above 15° is the best, and the reduction rates of total nitrogen (TN) and total phosphorus (TP) loads have reached about 25%. This study provides some reference for the management of NPS pollution in the Bahe River Basin and other similar basins.
اظهر المزيد [+] اقل [-]Relationship between tourism number and air quality by carbon footprint measurement: a case study of Jiuzhaigou Scenic Area
2021
Yuan, Hong | Nie, Kun-xi | Xu, Xiao-ya
Both the environmental and the ecological protection are key issues in the sustainable development of tourism. As a well-known world natural and cultural heritage, intensive study about the environment of Jiuzhaigou scenic spot has been launched since China’s natural landscape protection. The field of low-carbon tourism is starting to be explored in China, and this article uses the life cycle assessment theory to evaluate the footprint of Jiuzhaigou. We find that the air quality is closely related to the number of tourists. Therefore, to maintain the environment of Jiuzhaigou, the number of tourists is proposed to restrict. The contribution of this paper is to provide pricing theory for attracting potential tourists and to give a theoretical basis for controlling the number of tourists in Jiuzhaigou Scenic Area.
اظهر المزيد [+] اقل [-]Labor productivity of small-scale agriculture and its influence on agricultural landscape conservation in mountainous areas in China: a case study of rice farming in Hani terraced region
2020
Zhang, Yongxun | He, Lulu | Liu, Longteng | Min, Qingwen
Small-scale agriculture (SA) is regarded as unsustainability because of its low benefit. To protect traditional agricultural landscapes like terraces through SA will be difficult. However, in China, terraces are still maintained well by smallholders now. This study takes the family as a basic unit and SA in Hani terraced region as an object to explore its sustainability from the perspective of labor productivity (LP) through the questionnaire method. The findings are that peasant households work on both farm and non-farm jobs. They get a low income (3854.5 yuan RMB) from hybrid-rice-cropping and a high income (44,665.8 yuan RMB) from non-farm jobs but spend a small part of labors (34.23 person•days) in growing hybrid-rice and expended lots of labor (522 person•days) for non-farm jobs. In conclusion, LP of hybrid-rice-cropping is 1.32 times that of non-farm jobs for a household. The result shows SA in Hani terraced region has a higher return of labor investment than non-farm jobs. It is different from the common impression of the low benefit of SA and also explains why SA still continues to exist in the mountainous area in China now. However, SA in Hani terraced region also faces challenges with salary level rise of non-farm jobs and part-time farmers’ requirement for living quality improvement. In the future, promoting industrial integration development in this region to add local employment for improving farmers’ income is a feasible approach to protect terraced landscapes.
اظهر المزيد [+] اقل [-]Possibilities for increased carbon sequestration through the implementation of rational forest management in Russia
1997
Shvidenko, Anatoly | Nilsson, Sten | Roshkov, Vjacheslav
Huge areas of the Russian forests suffer from insufficient forest management. A scenario has been developed for an improved management program that would be implemented over the next 40 years. Possible options have been aggregated into three interlinked groups: increase in forest productivity through improvement of the forest conditions and the structure of the Forest Fund, decrease of carbon release by mitigation of disturbance regimes, and improvement of landscape management. One prerequisite in developing this scenario was that the cost of sequestering one ton of carbon should not exceed US$3 (1992 dollar value). In this article a simple model is described to illustrate the following possibilities for increased carbon fixation by improved forest management: large-scale reforestation and afforestation, replacement of stands with low productivity and replacement of so called soft deciduous species and “climax” stands, and implementation of rational silviculture (thinning). The results indicate a potential for an increase in carbon fixation in Russian forest ecosystems of 24.4 Pg over 100 years, after the first year that the actions discussed are implemented. The net sink of carbon was determined to be 16.5 Pg in the “low” estimate and 42.5 Pg in the “high” estimate. There are, however, many uncertainties in the data and there are difficulties in adequately modeling the possibilities for implementation under current conditions in Russia. In spite of these uncertainties, we conclude that there is great potential for economically justified increased carbon fixation through improved forest management in Russia.
اظهر المزيد [+] اقل [-]Variations in sulphur and nitrogen foliar concentration of deciduous and conifers vegetation in Slovakia
1997
Maňkovská, Blanka
The foliage contents of Sₜₒₜₐₗ and Nₜₒₜₐₗ were determined in 405 Permanent monitoring plots in four National Parks and sixteen Landscape Protection Areas and were compared with 1483 Permanent monitoring plots on Slovakia. The foliage content of S ranged from 0.72 to 6.77 g kg⁻¹ in hardwoods and from 0.98 to 4.3 g kg⁻¹ in softwoods. A critical increase was determined in one National Park and in four Landscape Protection Areas. The foliage content of N ranged from 9.7 to 48.7 g kg⁻¹ in softwoods, and from 7.8 to 51.4 g kg⁻¹ in hardwoods. An insufficient level of N was determined in one Landscape Protection Area and a critical increase in four Landscape Protection Areas. The sulphur to nitrogen ratio ranged from 0.08 to 0.176 in softwoods, and from 0.078 to 0.253 in hardwoods. The foliage surface on hitherto explored four National Parks and sixteen Landscape Protection Areas in network 4×4 km was covered by all categories of rigid fallout particles. Fly-ash from coal combustion were observed each of National Parks and Landscape Protection Areas by scanning electron microscopy. Mycelia and spore, mineral matters, sand and soil particles were present on all National Parks and Landscape Protection Areas. Particles derived from aluminium production were observed at three Landscape Protection Areas. Particles derived from cement production and from lime works were observed at two National Parks and six Landscape Protection Areas. Particles derived from ferrous metals industry were observed at each of National Parks and Landscape Protection Areas and particles typical for other technologies were present in three of National Parks and twelve Landscape Protection Areas.
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