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161.
The regional level has been recognized as a good scale for implementing actions towards sustainable development (SD). An important pathway to improve regional sustainability is to locally carry out long-term ecological planning. In order to reduce environmental impacts from fast economic growth, several eastern provinces of China began Ecological Province Construction (EPC) at the end of 1990s. This paper presented a case for analyzing the progress of EPC in China via both qualitative and quantitative methods. We studied Shandong Eco-province Construction (SEPC) and evaluated its outcomes with its pre-set indicators in 2003–2010. A further evaluation with eco-efficiency and de-linking indices was conducted. The results indicated the pre-set indicators could not effectively reflect of the ecological province construction. It was recommended to introduce an evaluated framework combined with eco-efficiency and de-linking indices to indicate ecological planning at the regional scale. 相似文献
162.
Yasuhiro Kimura Marie van der Merwe Stine B. Bering Himabindu Penmatsa Veronica G. Conoley Per T. Sangild Anjaparavanda P. Naren Randal K. Buddington 《Cytotechnology》2015,67(1):39-49
Transformed and cultured cell lines have significant shortcomings for investigating the characteristics and responses of native villus enterocytes in situ. Interpretations of results from intact tissues are complicated by the presence of underlying tissues and the crypt compartment. We describe a simple, novel, and reproducible method for preparing functional epithelia using differentiated enterocytes harvested from the small intestine upper villus of adult mice and preterm pigs with and without necrotizing enterocolitis. Concentrative, rheogenic glucose uptake was used as an indicator of epithelial function and was demonstrated by cellular accumulation of tracer 14C d-glucose and Ussing chamber based short-circuit currents. Assessment of the epithelia by light and immunofluorescent microscopy revealed the harvested enterocytes remain differentiated and establish cell–cell connections to form polarized epithelia with distinct apical and basolateral domains. As with intact tissues, the epithelia exhibit glucose induced short-circuit currents that are increased by exposure to adenosine and adenosine 5′-monophosphate (AMP) and decreased by phloridzin to inhibit the apical glucose transporter SGLT-1. Similarly, accumulation of 14C d-glucose by the epithelia was inhibited by phloridzin, but not phloretin, and was stimulated by pre-exposure to AMP and adenosine, apparently by a microtubule-based mechanism that is disrupted by nocodazole, with the magnitudes of responses to adenosine, forskolin, and health status exceeding those we have measured using intact tissues. Our findings indicate that epithelia prepared from harvested enterocytes provide an alternative approach for comparative studies of the characteristics of nutrient transport by the upper villus epithelium and the responses to different conditions and stimuli. 相似文献
163.
S. O. Ojeniyi 《Plant and Soil》1981,60(3):477-480
Summary The Ca, Mg, S, Mn and Cu contents in leaves ofCoffea canephora trees selected in 64 plots under a 4×4×2 NPK trial were determined after seven years of fertilizer application. It was observed that NPK applications increased Mn uptake, P application increased the uptake of Cu, Ca and S while application of N and K did not enhance the uptake of Cu, Mg, Ca and S. It was shown that as a result of NPK applications, Ca and Mg had become deficient in coffee leaves, which corroborates earlier findings based on soil analysis. 相似文献
164.
Modern human activities greatly disturb substance flows in nature and senselessly discard massive amounts of precious resources to natural waste reservoirs; phosphorus (P) is a good example of this. In this article, substance flow analysis is employed to quantify and explore the temporal evolution of China's P consumption in main metabolic nodes from 1984 to 2008, and then the environmental implications for P flows into both surface waters and natural soil are investigated. Results show that the metabolic nodes of human life and animal husbandry have demanded increasingly more P inputs, while disseminating more and more P wastes, with the waste recycling ratios of these processes dropping, respectively, from 65.9% and 66.1% in 1984 to 50.7% and 40.6% by 2008. These change traits were closely related to national polices including the Household Contract Responsibility System and the Shopping Basket Program, as well as the policy vacuum existing between China's agricultural and environmental administration departments. To achieve high crop yield, increasingly more inorganic P fertilizers have been utilized in China, but their use efficiency has decreased by 46.3%. From 2003 to 2008, the total P load into surface waters was stabilized at about 900.0 kilotons (kt), while the total P load into natural soil increased by more than 3.8 times to 3,131.3 kt P in 2008. City life and the intensive breeding of crops are identified as the main targets for further pollution control and nutrient recycling in China. Some suggestions for achieving environmentally sound practices and resource sustainability in China are proposed at the end of this article. 相似文献
165.
Corey Bragg Sam McKechnie Jamie Newman David Fletcher Henrik Moller Darren Scott 《New Zealand journal of zoology.》2013,40(3):275-289
Abstract Sooty shearwater (Puffinus griesus, titi) abundance, harvest levels and chick mass were monitored repeatedly on Putauhinu Island, south‐west of Rakiura (Stewart Island) between 1997 and 2005. Putauhinu is the second largest of the Titi Islands and has a relatively high density of chicks distributed over most of the island, so it supports what is likely the second‐largest population of sooty shearwaters in the Rakiura region (after Taukihepa, Big South Cape Island). Rakiura Maori harvested chicks from five “manu” (family birding areas) that covered 56% of the 128.4 ha of breeding colony of the island. Chick density was lower on the unharvested area in the interior of the island than on harvested areas. Burrow entrance density was higher where there was more ground cover (mainly fern) vegetation, but these areas had lower burrow occupancy, so overall chick density was similar at different levels of ground cover. Twenty‐six harvesters present on Putauhinu in 2005 took 31 280 chicks in total, equivalent to 8.4% (95% CI = 6.6–12%) of the available chicks on the entire island. Seasonal variation in total chicks harvested (CV 15–22%) was not related to chick abundance or mass. Refuges, including impenetrable patches of vegetated ground within manu, the unharvested centre of the island, and even nearby unharvested islands, will ameliorate localised impacts of harvest if density‐dependent immigration is operating. 相似文献
166.
Food waste (FW) management is a global conundrum because of the rapid population growth and growing economic activity. Currently, incineration and landfill are still the main means for FW management, while their environmental sustainability and economic viability have been in question. Recently, the biological processes including anaerobic digestion, aerobic composting, bioethanol fermentation, feed fermentation etc. have attracted increasing interest with the aims for energy and resource recovery from FW. However, these biological approaches have inherent drawbacks, and cannot provide a comprehensive solution for future FW management. Therefore, this review attempts to offer a critical and holistic analysis of current biotechnologies for FW management with the focus on the challenges and solutions forward. The biological approaches towards future FW management should be able to achieve both environmental sustainability and economic viability. In this instance, the concept of zero solid discharge-driven resource recovery has thus been put forward. According to which, several innovative biological processes for FW management are further elucidated with critical analysis on their engineering feasibility and environmental sustainability. It turns out that is an urgent need for turning current single task-orientated bioprocess to an integrated biological process with multiple tasks of concurrent recovery of water, resource and energy together with zero-solid discharge. 相似文献
167.
C. R. Spehar 《TAG. Theoretical and applied genetics. Theoretische und angewandte Genetik》1995,90(5):707-713
The Brazilian tropical adapted soybeans contains, in addition to superior morphological characters, genetic factors for tolerance to cultivation in acidic, mineral-stressed soils. However, the selection process for these hindrances has been empirical, and information on the genetics of mineral element uptake by the plant is necessary. The objective of this investigation was to identify the mode of inheritance for the absorption of phosphorus, potassium, calcium, magnesium, iron, aluminium, manganese, zinc and copper in a 9 × 9 diallel cross. General combining ability (GCA) was higher than specific combining ability (SCA), with the exception of copper, manganese and zinc, indicating predominantly additive effects. The ratios of GCA/SCA varied between 3.4 (calcium) and 8.5 (magnesium). The regression of covariance (Wr) on variance (Vr) showed that the additive-dominance model explained the genetic differences in this germ plasm. However, the detection of overdominance could be related to possible heterozygosity in the parental varieties for mineral absorption. Broad-sense heritability values were higher than narrow sense heritability values for aluminium, iron, potassium, calcium and magnesium, being in the range of 67.9–86.9% and 42.0–56.6%, respectively. This is an indication that soybeans can be further improved to efficient utilisation of nutrients and to tolerate toxic factors in the soil. 相似文献
168.
Being inspired in the process of teaching and studying on tourism geography and heritage landscapes, the author attempts to broaden the scope of traditional studies in landscape ecology. Upon reviewing the progress, limitations and boundaries of landscape ecology, he criticizes the negligence of waterscapes by academics. The author further examines some waterscape conservation policy programs practiced by different nations. These include 10 National Seashores, 4 National Lakeshores, 4 National Rivers, 13 National Marine Sanctuaries and 1 Marine National Monument in USA, 13 Marine National Parks, 11 Marine Sanctuaries and 4 multiple use Marine Reserves in the State of Victoria, Australia, 3 Marine Nature Reserves and 43 Heritage Coasts in UK, and 272 National Water Parks in China. Based on these explorations, the author proposes a few hypotheses on waterscape ecology. Finally, he concludes that as one among many sub-disciplines of applied ecology, waterscape ecology can only achieve its full-fledged growth through concerted efforts among academics, and the supports from both governments and non-government organizations. Meanwhile, the site-specific policy practices with the rapid increasing social needs will likely facilitate the development of this infant school. Hopefully, the birth and development of waterscape ecology will contribute to the prosperity of global academics and the maintenance of earth level environmental health. 相似文献
169.
Wulf-Peter Schmidt 《The International Journal of Life Cycle Assessment》2006,11(5):315-322
Background, Aim and Scope
Sustainability is a well recognised goal which is difficult to manage due to its complexity. As part of a series of sustainability
management tools, a Product Sustainability Index (PSI) is translating the sustainability aspects to the organization of vehicle
product development of Ford of Europe, thus allocating ownership and responsibility to that function. PSI is limiting the
scope to those key environmental, social and economic characteristics of passenger vehicles that are controllable by the product
development organisation.
Materials and Methods:
The PSI considers environmental, economic and social aspects based on externally reviewed life cycle environmental and cost
aspects (Life Cycle Assessment, Cost of ownership / Life Cycle Costing), externally certified aspects (allergy-tested interior)
and related aspects as sustainable materials, safety, mobility capability and noise. After the kick-off of their product development
in 2002, the new Ford S-MAX and Ford Galaxy are serving as a pilot for this tool. These products are launched in Europe in
2006. The tracking of PSI performance has been done by engineers of the Vehicle Integration department within the product
development organization. The method has been translated in an easy spreadsheet tool. Engineers have been trained within one
hour trainings. The application of PSI by vehicle integration followed the principle to reduce the need for any incremental
time or additional data to a minimum. PSI is adopted to the existing decision-making process. End of 2005, an internal expert
conducted a Life Cycle Assessment and Life Cycle Costing (LCC) study for verification purposes using commercial software.
This study and the PSI have been scrutinized by an external review panel according to ISO14040 and, by taking into consideration
the on-going SETAC, work in the field of LCC.
Results:
The results of the Life Cycle based indicators of PSI as calculated by non-experts are fully in line with those of the more
detailed expert study. The difference is below 2%. The new Ford Galaxy and Ford S-MAX shows significantly improved performance
regarding the life cycle air quality, use of sustainable materials, restricted substances and safety compared to the previous
model Galaxy. The affordability (Life Cycle Cost of Ownership) has also been improved when looking at the same engine types.
Looking at gasoline versus diesel options, the detailed study shows under what conditions the diesel options are environmentally
preferable and less costly (mileage, fuel prices, etc.).
Discussion:
The robustness of results has been verified in various ways. Based also on Sensitivity and Monte-Carlo Analysis, case study-specific
requirements have been deduced defining criteria for a significant environmental improvement between the various vehicles.
Only if the differences of LCIA results between two vehicles are larger than a certain threshold are the above-mentioned results
robust.
Conclusions:
In general terms, an approach has been implemented and externally reviewed that allows non-experts to manage key environmental,
social and economic aspects in the product development, also on a vehicle level. This allows mainstream functions to take
ownership of sustainability and assigns accountability to those who can really decide on changes affecting the sustainability
performance. In the case of Ford S-MAX and Galaxy, indicators from all three dimensions of sustainability (environment, social
and economic) have been improved compared to the old Ford Galaxy.
Recommendations and Perspectives:
Based on this positive experience, it is recommended to make, in large or multinational organizations, the core business functions
directly responsible and accountable for managing their own part of environmental, social and economic aspects of sustainability.
Staff functions should be limited to starting the process with methodological and training support and making sure that the
contributions of the different main functions fit together. 相似文献
170.
Daisy H. Dent Robert Bagchi David Robinson Noreen Majalap-Lee David F. R. P. Burslem 《Plant and Soil》2006,288(1-2):197-215
The extent to which plant communities are determined by resource availability is a central theme in ecosystem science, but patterns of small-scale variation in resource availability are poorly known. Studies of carbon (C) and nutrient cycling provide insights into factors limiting tree growth and forest productivity. To investigate rates of tropical forest litter production and decomposition in relation to nutrient availability and topography in the absence of confounding large-scale variation in climate and altitude we quantified nutrient fluxes via litterfall and leaf litter decomposition within three distinct floristic associations of tropical rain forest growing along a soil fertility gradient at the Sepilok Forest Reserve (SFR), Sabah, Malaysia. The quantity and nutrient content of small litter decreased along a gradient of soil nutrient availability from alluvial forest (most fertile) through sandstone forest to heath forest (least fertile). Temporal variation in litterfall was greatest in the sandstone forest, where the amount of litter was correlated negatively with rainfall in the previous month. Mass loss and N and P release were fastest from alluvial forest litter, and slowest from heath forest litter. All litter types decomposed most rapidly in the alluvial forest. Stand-level N and P use efficiencies (ratios of litter dry mass to nutrient content) were greatest for the heath forest followed by the sandstone ridge, sandstone valley and alluvial forests, respectively. We conclude that nutrient supply limits productivity most in the heath forest and least in the alluvial forest. Nutrient supply limited productivity in sandstone forest, especially on ridge and hill top sites where nutrient limitation may be exacerbated by reduced rates of litter decomposition during dry periods. The fluxes of N and P varied significantly between the different floristic communities at SFR and these differences may contribute to small-scale variation in species composition. 相似文献