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1.
和全国其他地方一样,廊坊市在大力推进社会主义新农村建设的过程中,也面临着农村生态环境恶化的困境。为了实现农业生产发展和农村生态环境保护之间的平衡,政府应当加大公共财政支出向农村地区倾斜的力度,坚持规划先行、服务跟进的原则,切实改善人居环境,强化农村生态环境保护法制的实施,把新农村建设成为生态良好的新农村。  相似文献   
2.
This paper will review the potential of a relatively new type of testbed platform for environmental education and research because of the unique advantages resulting from their material closure and separation from the outside environment. These facilities which we term “modular biospheres”, have emerged from research centered on space life support research but offer a wider range of application. Examples of this type of facility include the Bios-3 facility in Russia, the Japanese CEEF (Closed Ecological Experiment Facility), the NASA Kennedy Space Center Breadboard facility, the Biosphere 2 Test Module and the Laboratory Biosphere. Modular biosphere facilities offer unique research and public real-time science education opportunities. Ecosystem behavior can be studied since initial state conditions can be precisely specified and tracked over different ranges of time. With material closure (apart from very small air exchange rate which can be determined), biogeochemical cycles between soil and soil microorganisms, water, plants, and atmosphere can be studied in detail. Such studies offer a major advance from studies conducted with phytotrons which because of their small size, limit the number of organisms to a very small number, and which crucially do not have a high degree of atmospheric, water and overall material closure. Modular biospheres take advantage of the unique properties of closure, as representing a distinct system “metabolism” and therefore are essentially a “mini-world”. Though relatively large in comparison with most phytotrons and ecological microcosms, which are now standard research and educational tools, modular biospheres are small enough that they can be economically reconfigured to reflect a changing research agenda. Some design elements include lighting via electric lights and/or sunlight, hydroponic or soil substrate for plants, opaque or glazed structures, and variable volume chambers or other methods to handle atmospheric pressure differences between the facility and the outside environment.  相似文献   
3.
农业特色产业作为新的经济增长点,并且日益成为目前农村经济发展面临的新课题和拉动内需的新机遇。同时也应该看到,由于长期不合理的盲目开发等原因,农业生态环境恶化和自然资源紧缺的问题日益严峻,生态农业问题的提出是农业经济可持续发展的必然。本文结合河北省农业特色产业的发展现状,总结其存在的问题,分析河北省农业特色产业集群的可行性,进而提出以增长极理论为理论基础,构建生态园型的农业特色产业集群的相关建议。  相似文献   
4.
A mixed crop consisting of cowpeas, pinto beans and Apogee ultra-dwarf wheat was grown in the Laboratory Biosphere, a 40 m3 closed life system equipped with 12,000 W of high pressure sodium lamps over planting beds with 5.37 m2 of soil. Similar to earlier reported experiments, the concentration of carbon dioxide initially increased to 7860 ppm at 10 days after planting due to soil respiration plus CO2 contributed from researchers breathing while in the chamber for brief periods before plant growth became substantial. Carbon dioxide concentrations then fell rapidly as plant growth increased up to 29 days after planting and subsequently was maintained mostly in the range of about 200–3000 ppm (with a few excursions) by CO2 injections to feed plant growth. Numerous analyses of rate of change of CO2 concentration at many different concentrations and at many different days after planting reveal a strong dependence of fixation rates on CO2 concentration. In the middle period of growth (days 31–61), fixation rates doubled for CO2 at 450 ppm compared to 270 ppm, doubled again at 1000 ppm and increased a further 50% at 2000 ppm. High productivity from these crops and the increase of fixation rates with elevated CO2 concentration supports the concept that enhanced CO2 can be a useful strategy for remote life support systems. The data suggests avenues of investigation to understand the response of plant communities to increasing CO2 concentrations in the Earth’s atmosphere. Carbon balance accounting and evapotranspiration rates are included.  相似文献   
5.
以福建省云霄县作为探讨案例,根据存在的生态环境问题,并结合土地利用现状,提出创建环境友好型土地利用模式、大力加强生态建设、加强区域环境整治力度三点建议,从而探讨县域土地利用与生态环境协调发展的可行性。  相似文献   
6.
Processes which produce slow changes in air composition in a closed ecological system (CES) may not be noticed if the leak rate of the CES is significant. Dilution of the system’s air with outside air can mask these processes. A tightly closed CES provides the opportunity for slow changes to accumulate over time and be observed and measured. Biosphere 2 (volume 200,000 m3) had a low leak rate of less than 10 percent per year. Oxygen declined slowly at varying rates reflecting seasonal influences, which averaged to about 140 ppm per day during the first 16 months of the two-year closure. Computer simulations of the observed rate of oxygen loss combined with other hypothetical leak rates suggest that the decline would have been hidden by a leak rate as low as one percent per day. Sealing Biosphere 2 involved rigorous design specifications and inclusion of two expansion chambers (called “lungs”) to accommodate expansion/contraction of the atmosphere, which enabled limiting the pressure difference between inside and outside atmospheres to the range of ±8 Pa (0.08 mBar). Measurement of leak rate was by two methods: the first, measuring the rate of deflation of the lungs while holding a constant elevated pressure differential enabled calculation of an estimated leak rate within the usual operating pressure differential range; the second was to measure the progressive dilution of trace gases spiked into the atmosphere. Both methods confirmed leakage to be less than 10 percent per year. Operational data from the 40 m3 Laboratory Biosphere is used to illustrate how normal variations of temperature, humidity and barometric pressure would combine to force leakage and rapidly dilute the internal atmosphere if it were not equipped with a lung. It is demonstrated that very high degrees of closure for a CES enable experimental observation of small imbalances in atmospheric cycles or slow accumulation of trace gases that could otherwise be masked by dilution with atmosphere external to the CES.  相似文献   
7.
着力抓好“发展环境”和“生态环境”建设,是河北省委和廊坊市委作出的重大战略部署,意义重大。廊坊市的“两个环境”改善工作要以十八大精神为指导,不断加大基础设施建设和工业园区的建设力度,提高机关行政办事效率和服务水平;同时要建设良好的生态环境,发展绿色循环经济,加强城市绿化和农业生态建设。  相似文献   
8.
中部地区可持续发展存在的问题与对策   总被引:3,自引:0,他引:3  
由于长期以来存在的落后观念、粗放的经济增长方式和传统管理体制带来的弊端,我国中部地区可持续发展面临着自然资源对经济和社会发展的支撑能力下降、资源浪费严重、环境污染突出、自然灾害频繁、人口增长过快、总体素质较低等问题。因此,中部各省必须以科学发展观为指导,增强可持续发展意识,推行绿色改革,加强制度建设,大力发展循环经济,提高可持续发展能力,从而实现可持续发展。  相似文献   
9.
文章根据生态足迹成分法的基本原理和计算模型,通过调查南昌航空大学前湖校区2008年的能源(天然气、电力)、食物、垃圾、纸张、水和校际交通六个方面的消费情况,以此计算与评价了南昌航空大学前湖校区2008年的校园生态足迹和生态效率,并提出保持措施。研究结果表明,南昌航空大学前湖校区2008年总生态足迹为10763.19hm2,人均生态足迹为0.592hm2/生,人均生态效率为1.689hm2/生,与全国人均生态足迹1.5hm2/人相比较,学校的生态状况比较乐观。  相似文献   
10.
农业特色产业作为新的经济增长点,并且日益成为目前农村经济发展面临的新课题和拉动内需的新机遇。同时也应该看到,由于长期不合理的盲目开发等原因,农业生态环境恶化和自然资源紧缺的问题日益严峻,生态农业问题的提出是农业经济可持续发展的必然。本文结合河北省农业特色产业的发展现状,总结其存在的问题,分析河北省农业特色产业集群的可行...  相似文献   
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