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81.
Phosphorus (P) use in global food and bioenergy production needs to become more efficient and sustainable to reduce environmental impacts and conserve a finite and critical resource (Carpenter & Bennett, Environmental Research Letters, 2011, 6, 014009; Springmann et al., Nature, 2018, 562, 519). Sugarcane is one crop with a large P footprint because production is centered on P‐fixing soils with low P availability (Roy et al., Nature Plants, 2016, 2, 16043; Withers et al., Scientific Reports, 2018, 8, 2537). As global demand for processed sugar and bioethanol continues to increase, we advocate that improving P efficiency could become a key sustainability goal for the sugarcane industry. Here, we applied the 5R global P stewardship framework (Withers et al., Ambio, 2015, 44, 193) to identify more sustainable options to manage P in Brazilian sugarcane production. We show that current inputs of P fertilizer to the current crop area could be reduced by over 305 Gg, or 63%, over the next three decades by reducing unnecessary P fertilizer use, better utilization of recyclable bioresources and redesigning recommendation systems. Adoption of these 5R options would save the sugarcane industry in Brazil 528 US$ million and help safeguard global food and energy security.  相似文献   
82.
The objective of a circular economy (CE) is to maintain the value of products, materials, and resources in the economy by closing material loops and minimizing waste generation. In recent years, the role of public procurement has been recognized as an important, but as yet not fully exploited, opportunity by cities and municipalities in their transition toward circular societies. This study analyzed public procurement opportunities to promote CE. Different approaches and examples of circular public procurement were identified using case studies. In addition, opportunities to promote CE through sustainable and green public procurement policy were identified analyzing predefined sustainable or green public procurement criteria. The study concludes that public procurement can promote CE and related business models by setting criteria and requirements for the extension of product life spans, efficiency and/or intensity of use, and efficient cycling of biological or technical materials, as well as for the securing of clean and nonrisky cycles. Circular procurement can occur through the procurement of better‐quality products in circular terms, the procurement of new circular products, the use of business concepts that support the CE, and investments in circular ecosystems. Several sectors and product groups were identified as having potential for circular procurement, such as construction, waste, and wastewater management, transportation, food, and catering, furniture, and textiles. The study also suggests that the use of certain tools, such as performance‐based procurement, life cycle approach, and life cycle costing, as well as criteria concerning reuse and recycling of materials, could promote circular procurement. Market dialogue and cooperation between procurers and actors in the supply chains are important for the future development of circular procurement.  相似文献   
83.
The implementation of global sustainability has gained worldwide attention in recent years. The Organization Environmental Footprint, which encompasses 14 impact categories, is a multicriteria measure of the environmental performance of goods and services provided by an organization from a life cycle perspective. In this article, the focus is on quantifying the Organization Environmental Footprint of a construction company in Spain. By applying an environmentally extended input‐output approach, its total footprint and impacts along the supply chain from two consecutive years were calculated. The results show that the environmental impacts from the second year of implementation were significantly higher than those from the first year. The impact category climate change was found to have experienced the greatest increase from one year to the other, with a 31% increase. This work provides an overview of 14 environmental impact categories of the company assessed, as well as recommendations for the implementation of this indicator in companies and public procurement. This approach could pave the way to shape organizations’ action plans and meet the European environmental challenges.  相似文献   
84.
Grassland management intensification can greatly influence nitrogen (N) dynamics between aboveground and belowground compartments mainly because of the large amount of available N forms, which are repeatedly added to soils. A better understanding of how chronic fertilisation might affect N use efficiency (NUE) in plants can contribute to reducing N losses from soils and improve the sustainability of managed grasslands. Here we address how NUE might be affected by (1) the addition of key nutrients (e.g. N, P, K, Mg) in different combinations, (2) grazing by rabbits, and (3) liming (i.e. CaCO3 applications) in a 22-year-old permanent grassland experiment established in Berkshire, UK, in 1991. We first calculate seven different NUE indexes, which are known to respond either to changes in soil N availability (i.e. endogenous N inputs from soil N mineralization processes) or to exogenous N inputs (i.e. synthetic N fertiliser). We found that plant NUE calculated as plant biomass produced per unit of N acquired significantly decreased under the chronic addition of multiple nutrients (NPKMg) and was even lower under N-only applications. Most NUE indexes significantly decreased under grazing but greatly increased under liming applications. We found evidence that NUE indexes, which accounted for endogenous N sources decreased at increased rates of soil N mineralization. Finally, we found no significant relationships between any of the NUE indexes and estimates of soil N losses (Mg N ha−1) or N retention in soils (i.e. units of soil N retained per unit of N added) calculated from changes in net soil N budget over 22 years. Our study carried out on relatively acidic sandy soils suggests how liming applications in combination with low levels of multi-nutrient additions (NPKMg) can significantly improve plant biomass production per unit of N added thus contributing to enhance the sustainability of managed grassland ecosystems.  相似文献   
85.
为了解红厚壳(Calophyllum inophyllum)的抗逆特性,对西沙群岛自然生长的红厚壳叶片的形态解剖、生理生态、以及叶片和适生土壤的元素含量进行了研究。结果表明,红厚壳是阳生性植物,其上表皮厚,海绵组织发达且栅栏组织排列紧密,气孔排列松散且密度小(24.40 mm~(-2)),有利于叶片保水抵御干旱。叶片的叶绿素a、b含量低(分别为0.87和0.43 mg g~(-1)),表明红厚壳具适应强光环境的能力。叶片的MDA含量低(13.46 nmol g~(-1)),PRO含量高(127.89μg g~(-1)),SOD活性高(149.42 U g~(-1)),总抗氧化能力高(388.60 U g~(-1)),显示红厚壳能通过提高自身的抗氧化能力抵御膜脂过氧化伤害。红厚壳自然生长的珊瑚岛土壤较为贫瘠、营养元素含量低,但红厚壳植株体内具有较高的营养元素含量,表明红厚壳营养元素利用率高,对于贫瘠土壤具有很好的适应能力。因此,红厚壳具有较高的抗氧化胁迫能力和耐受干旱的能力,适宜生长在热带珊瑚岛等土壤贫瘠的生境,可以作为热带珊瑚岛防风固沙和植被恢复的工具种。  相似文献   
86.
再论可持续性科学: 新形势与新机遇   总被引:3,自引:0,他引:3  
近10年来,可持续性科学蓬勃发展,已成为21世纪全球普遍关注的一个重要的新科学领域.然而,在大力提倡可持续发展和生态文明建设的中国,可持续性科学尚未引起科学家和实践者的足够重视.为促进可持续性科学在中国的发展,2014年邬建国等曾撰文介绍什么是可持续性科学.本文进一步探讨了这一问题,并补充阐述了可持续性科学与可持续发展研究的关系、可持续性科学的科学范式及其8个基本论题.基于对可持续性科学发展动态的分析,作者认为,一方面,可持续性科学已进入系统推进的成熟发展期;另一方面,虽然我国可持续发展研究、实践与教育的热情高涨,但在可持续性科学领域起步较晚,落后于主要发达国家和南非.为此,本文在文献综述的基础上,提出促进中国发展可持续性科学的“三位一体”策略:一是“请进来”以服务中国实践;二是“走出去”以贡献中国智慧;三是“中西医结合”以引领学科发展.  相似文献   
87.
A conceptual framework is developed and used for improving the livelihood of Sub-Saharan communities faced with multiple stresses resulting from adverse environments, vector-transmitted diseases, and limited food. Ecosocial systems are the units for management. The accumulation of ecological, economic, and social capital is the objective of management, the reduction of maintenance costs is the key strategy, and technologies must satisfy ecological, economic, and social criteria. Interacting social system components are communities, facilitators, scientists, and political as well as administrative organizations. An adaptive approach to management allows flexibility in human and financial resource allocation and results in changes in knowledge and efficacy of management operations. The implementation strategy at two sites in Ethiopia relies on a two-stage procedure. In Stage 1, human and cattle health management set the conditions for development. In Stage 2, the ecosocial system is kept on a trajectory to enhanced ecological, economic, and social capital. In each stage, the assignment of responsibilities leads to four implementation phases. In Stage 1, successful precision targeting of tsetse and drug-based Trypanosoma spp. control increased the economic and social capital at the Luke site in southwestern Ethiopia but threatened the ecological capital because of overstocking and land degradation. In Stage 2, a women’s group living in the outskirts of Addis Ababa (Ethiopia) transformed barren land into a horticultural enterprise to enhance ecosystem service provision, including production of horticultural goods, and increase soil fertility expressed by nutrients and water availability. This article reviews concepts on human livelihood improvement in Sub-Saharan Africa and identifies principles that became important during project execution.  相似文献   
88.
In Iran, mangroves are located in the south of the country, where they fulfill essential ecosystem functions, but some parts of them have been destroyed for various reasons in recent years so that it seems necessary to have a management plan consistent with the conservation of this ecosystem. But, it needs knowledge of the trend of and reasons for the degradation of these forests. So, the primary idea of this research was to discover the factors involved in the degradation of these forests and how to manage them. So, the research first used the remote sensing technique to determine the rate of their degradation over the last 20 years. Then, using the Delphi technique, 45 factors were identified for the degradation of these forests and they were classified into five categories including climatic and environmental, anthropogenic, socioeconomic, psychological, and policymaking and legal. Finally, the analytic hierarchy process (AHP) was used to rank these factors within two management paradigms of remediability and preventability so that the ecosystem can be soundly managed by classifying these factors. Overall, the results can provide policymakers with new insights into forest management and the policies presented here can contribute to the sustainability of this ecosystem.  相似文献   
89.
The global trade in ornamental fish involves c. 125 countries worldwide and is worth c. US $15–30 billion each year. This total is dominated (90%) by freshwater fishes, most of which are sourced from breeding facilities located in developing countries, typically in Asia or South America, but also in Israel, USA and Europe. Some fish are still obtained from natural (wild) sources, but the exact percentage of wild-caught fish is difficult to quantify given a lack of reliable data. Although c. 1000 species of freshwater fishes are widely available (from a total of > 5300 on sale), the most dominant freshwater fishes in the market comprise only 30 species from the orders Cyprinodontiformes, Perciformes, Characiformes and Siluriformes. In this perspectives review paper, illustrative example case studies of wild-fish collecting (Barcelos and Rio Xingu, Brazil) and breeding projects (Java, Indonesia) are described. In addition, wild-collecting expeditions to West Papua, Indonesia are discussed, focused on discovering novel species of rainbowfish (Melanotaeniidae) for breeding in captivity. Sustainability of the aquarium industry is considered in its broadest sense. The aquarium industry has been portrayed as both a major threat to natural ecosystems, but also as being part of the solution in terms of helping to maintain species when they have gone extinct in the wild or offering an income to impoverished citizens who might otherwise engage in much more destructive practices.  相似文献   
90.
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