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91.
中国大型高等真菌生物多样性的关键类群   总被引:14,自引:0,他引:14  
由于生物多样性的关键类群在科学研究、社会经济及生态系统中所处的重要地位,有必要对其进行筛选和确定。在多年的野外考察和有关文献资料分析的基础上,参照植物和动物关键类群的划分原理及方法,结合高等真菌的特点将大型高等真菌划分为3种类型:濒危类群、重大科学价值类群和重要经济类群。其中,濒危类群指在近年的考察和报告中发现的数量急剧减少或由于过度的采集资源明显受到威胁的种类,其中有虫草属(Cordyceps)的中华虫草(C.siaensis)、块菌属(Tuber)的中华块菌(T.sinense)、假下陷块菌(T.pseu—doexcawatum)、喜马拉雅块菌(T.himalayense)、革菌属(Thelephora)的干巴菌(T.ganbajun)、口蘑属的松茸(Tricholoma matsuatke)及其近缘种和蒙古口蘑(T.mongolicum);重大科学价值类群指在真菌系统演化或与动、植物和其它真菌协同进化中的一些重要类群,或在应用研究领域具重要价值的类群,如鸡Zong菌属(Termitomyces)、鹅膏属(Amanita)、腹菌与伞菌的过渡类型如地红菇属(Macowanites)、粉褶包属(Richoniella)、轴腹菌属(Hydnangium)、腹牛肝菌属(Gastroboletus)等、牛肝菌类中的一些特殊单种属和寡种属如圆花孢牛肝菌属(Heimiel-la)、圆孔牛肝菌属(Gyroporus)等;重要经济类群指广为利用的食用菌、药用菌和外生菌根菌,其中主要有虫草属的中华虫草、块菌属的中华块菌、鸡Zong菌属盾尖鸡Zong菌(T.dypeatus)、鸡Zong菌(T.ewrhizus)、球形鸡Zong菌(T.gtoulus)、口蘑属的松茸群及蒙古口蘑、牛肝菌属(Bolaus)的美味牛肝菌(B.edulis)、小美牛肝菌(R.speciosus)、茶褐牛肝菌(B.brunneissimus)等,乳菇的红汁乳菇(L,hatsudake)、松乳菇(L.deliciosus)、多汁乳菇(L.volemus)、红菇属的变绿红菇(R.vir-escens)、蓝黄红菇(R.cyanoxantha)、鹅膏属的红黄鹅膏(A.hemibapha)、隐花青鹅膏(A.mang-iniana)、灵芝属(Ganoderma)的灵芝(G,lucidum)及紫芝(G,sinense)、竹荪属(Dictyophora)、豆马勃属(Pisdithus)的一些种。这些种由于具有重要的经济价值而受到过度的采集,故往往与濒危的种类一致。关键类群的筛选与提出为大型高等真菌的研究、应用和保护提供参考。  相似文献   
92.
Considerable behavioural evidence supports harassment by insects as the most important causal link between warm summer temperatures and low body condition of reindeer Rangifer tarandus , and that insect activity is influenced by weather condition. However, much less is known about the effect of insect harassment on individual performance, measured as reduced weight gain during summer, and the related consequences on both the reindeer pastoral economy and reindeer as a biological resource. Using climatic data, this paper develops a simple index for the analysis of insect harassment that takes into consideration weather variables known to significantly affect insect activity and/or the level of insect harassment. The insect harassment index, which is based on mid-day ambient temperature ≥13 °C, wind speed <6 m/s and cloud cover <40%, is further used to test the hypothesis that insect harassment has a negative effect on reindeer performance during summer in three Norwegian populations. Results show that harassment by insects negatively affects the autumn weight of reindeer calves, most probably through reduced grazing time and increased energy expenditure, but also indirectly by negatively influencing milk production of the dam. Moreover, female calves were more vulnerable to insect harassment than males. Insect harassment may have consequences on future reproductive performance, calving time, calf birth weight and hence neonatal mortality, and thus affect reindeer productivity. The presented index is easy to estimate and may be used to quantify and compare harassment levels on various reindeer summer grazing areas for management purposes. Our results also suggest that the expected temperature increase in the course of global warming may increase the insect-related stress on reindeer.  相似文献   
93.
In the light of a circular economy, the Nijhuis Ammonia Recovery system (AECO‐NAR) was developed to not only remove nitrogen from wastewater streams, but also produce ammonium sulfate (AS), used as fertilizer, in a single plant. The goal of this paper was to quantify the environmental impacts of side stream ammonia recovery with the AECO‐NAR system and compares them with the impacts of side stream nitrogen removal combined SHARON (partly nitrification)‐anammox plant. For this, an environmental life cycle assessment was performed with a functional unit (FU) of the treatment of 1 kg of total dissolved nitrogen inflow. Since AS obtained by the AECO‐NAR is a by‐product of the ammonia removal process, allocation was based on system expansion. Foreground inventory data were obtained from a full‐scale plant. ReCiPe2016 was used to determine human health and biodiversity impacts. Results show that due to the production of AS in an integrated water treatment and production system, the AECO‐NAR avoids impacts of current AS production, leading to negative impact scores. Impacts per FU decrease with increasing inflow concentrations of ammonia. Main improvement options are the use of renewable energy and the replacement of the cleaning chemical citric acid with a sustainable alternative. Total impacts of the AECO‐NAR system diminish when comparing the system to the biological SHARON‐Anammox system, due to production of AS fertilizer product. Due to the fertilizer production step being integrated in the side stream treatment, the complete system is beneficial over ammonia recovery and wastewater treatment as separate systems.  相似文献   
94.
王怡然  张大红  吴宇伦 《生态学报》2020,40(8):2793-2801
森林生态安全对于维持生物多样性、促进经济可持续发展、保障人类生存具有重要影响,本文主要探讨森林生态安全的影响因素以及森林生态安全指数时间与空间变化情况,以期为提高浙江省森林生态安全状况提供理论参考。基于DPSIR(驱动力-压力-状态-影响-响应,Driving force-Pressure-State-Impact-Responses)模型,运用专家法、熵权法等确定浙江省森林生态安全指数,从县区角度对浙江省2000—2015年森林生态安全指数进行计算与分析,并通过绘制森林生态安全指数空间分布图观察森林生态安全空间变化状况。研究结果表明:(1)响应指标权重最大,政府政策作用显著,财政支持效果明显。(2)浙江省森林生态安全等级为较安全,森林生态安全指数分布在0.4—0.5之间,呈现波动式上升趋势。(3)状态指标的影响最明显,其次是压力指标、影响力指标、驱动力指标与响应指标;天然林面积减少是造成状态指标作用下降的主要原因;响应指标受其他指标的相互作用,上升趋势明显;经济发展一定程度上抑制了浙江省森林生态安全环境的改善与指数的提高。(4)浙江省森林生态安全指数地区分布不均匀,西南部地区森林生态安全指数高于东北部地区,县区指数差异明显,受自然环境与经济发展的双重影响。针对上述时空变化情况得出,浙江省应加大政策的扶持力度,增加林业生态建设投资;加快产业转型,实行循环经济,延长企业产业链;加强森林保护区的建设力度,制定相关条例规范人们行为的对策建议。  相似文献   
95.
In view of recent studies of the historical development and current status of industrial symbiosis (IS), life cycle assessment (LCA) is proposed as a general framework for quantifying the environmental performance of by‐product exchange. Recent guidelines for LCA (International Reference Life Cycle Data System [ILCD] guidelines) are applied to answer the main research questions in the IS literature reviewed. A typology of five main research questions is proposed: (1) analysis, (2) improvement, and (3) expansion of existing systems; (4) design of new eco‐industrial parks, and (5) restructuring of circular economies. The LCA guidelines were found useful in framing the question and choosing an appropriate reference case for comparison. The selection of a correct reference case reduces the risk of overestimating the benefits of by‐product exchange. In the analysis of existing systems, environmentally extended input‐output analysis (EEIOA) can be used to streamline the analysis and provide an industry average baseline for comparison. However, when large‐scale changes are applied to the system, more sophisticated tools are necessary for assessment of the consequences, from market analysis to general equilibrium modeling and future scenario work. Such a rigorous application of systems analysis was not found in the current IS literature, but would benefit the field substantially, especially when the environmental impact of large‐scale economic changes is analyzed.  相似文献   
96.
Innovative waste recycling through industrial processes such as industrial and urban symbiosis has long been practiced and recently received much attention in the field of industrial ecology, with researchers making efforts to identify key contributing factors to successful industrial symbiosis. By analyzing 88 sample recycling projects in 23 eco‐towns in Japan, this article focuses on the factors of project scale, recycling boundary, and types of waste in relationship to environmental benefits and operational performance. The results showed that larger eco‐towns achieved more savings of virgin materials and higher stability in operation. Large‐scale projects tended to locate closer to the users of recycled products than did small‐scale projects. For treating similar types of waste, projects producing recycled products for special users (e.g., feedstock to a blast furnace for iron production) tended to locate closer to the users than those not producing for special users. The type of waste had a strong effect on the savings of virgin materials and recycling boundaries, while local factors had significant impacts on operational performance. The results also showed that agglomeration did not significantly contribute to the environmental benefits or operational performance of eco‐town projects. Another finding was that national agencies were helpful for facilitating cross‐prefecture transportation and long‐distance transaction of wastes. Implications of the findings are also discussed.  相似文献   
97.
The functional groups of plants that characterize different phases of succession are expected to show differences in root distribution, fine‐root traits and degrees of association with arbuscular mycorrhizal (AM) fungi. The relationship involving fine‐root traits and AM fungi that regulate the nutrient acquisition potential among different plant functional groups are still not well understood. We assessed fine‐root morphology, AM fungal variables and soil fertility in grassland, secondary forest and mature forest in Atlantic, Araucaria and Pantanal ecosystems in Brazil. Soil cores were collected at 0–10 and 10–20 cm depths. Fine roots were extracted from soil by sieving and root morphological traits and AM colonization were determined. The AM spores were extracted from soil and counted. In all ecosystems, soil fertility, fine‐root mass and root diameter increased with the succession, while root length, specific root length, root‐hair length, root‐hair incidence, AM colonization and AM spore density decreased. These results suggest that plant species from early stages of tropical succession with inherent rapid growth invest in fine roots and maintain a high degree of AM colonization in order to increase the capacity for nutrient acquisition. Conversely, fine root morphological characteristics and low degree of AM colonization exhibited by plants of the later stages of succession lead toward a low nutrient uptake capacity that combine with their typical low growth rates. Abstract in Portuguese is available at http://www.blackwell‐synergy.com/loi/btp .  相似文献   
98.
中国产业共生发展模式的国际比较及对策   总被引:2,自引:0,他引:2  
石磊  刘果果  郭思平 《生态学报》2012,32(12):3950-3957
产业共生和生态工业园区已经成为世界范围内产业生态化转型的重要手段之一。在厘清产业共生发展模式内涵的基础上,借鉴商业模式的划分准则辨识了世界范围内6种产业共生模式:丹麦卡伦堡模式、美国模式、英国模式、日本模式、韩国模式和中国模式。从关键参与者、核心能力以及资金流3个维度对这些模式进行了辨识,重点比较了我国产业共生与其他模式的差别。研究表明,我国产业共生实践数量众多,在关键参与主体、核心能力培育和资金流等方面存在丰富的多样化,虽然形成了一定的中国特色,但并没有形成固定的"中国模式"。可以说,我国的产业共生实践还停留在初级阶段,下一步可持续的发展必须要建立合理的管制架构、形成稳定的资金支持机制和培育核心竞争能力。初级提出了我国产业共生和生态工业园区建设的政策建议。  相似文献   
99.
This review provides a contemporary account of knowledge on aspects of introductions of non‐native fish species and includes issues associated with introduction pathways, ecological and economic impacts, risk assessments, management options and impact of climate change. It offers guidance to reconcile the increasing demands of certain stakeholders to diversify their activities using non‐native fishes with the long‐term sustainability of native aquatic biodiversity. The rate at which non‐native freshwater fishes have been introduced worldwide has doubled in the space of 30 years, with the principal motives being aquaculture (39%) and improvement of wild stocks (17%). Economic activity is the principal driver of human‐mediated non‐native fish introductions, including the globalization of fish culture, whereby the production of the African cichlid tilapia is seven times higher in Asia than in most areas of Africa, and Chile is responsible for c. 30% of the world's farmed salmon, all based on introduced species. Consequently, these economic benefits need balancing against the detrimental environmental, social and economic effects of introduced non‐native fishes. There are several major ecological effects associated with non‐native fish introductions, including predation, habitat degradation, increased competition for resources, hybridization and disease transmission. Consideration of these aspects in isolation, however, is rarely sufficient to adequately characterize the overall ecological effect of an introduced species. Regarding the management of introduced non‐native fish, pre‐introduction screening tools, such as the fish invasiveness scoring kit (FISK), can be used to ensure that species are not introduced, which may develop invasive populations. Following the introduction of non‐native fish that do develop invasive populations, management responses are typified by either a remediation or a mitigation response, although these are often difficult and expensive to implement, and may have limited effectiveness.  相似文献   
100.
采用分解袋法,研究了长白山次生针阔混交林内9种树种叶凋落物34个月的分解过程.结果表明:在次生针阔混交林中,不同树种叶凋落物的初始N和P浓度存在很大差异,叶凋落物分解速率(k)与初始N浓度和C/N显著相关.有机物剩余百分率与C剩余百分率呈显著的线性正相关关系,与N和P剩余百分率之间呈显著的二项式回归关系. N和P剩余百分率在初期阶段随有机物分解而增加,达到峰值后逐渐降低. 随着有机物剩余百分率的下降,C/N和C/P均呈逐渐降低趋势,各种叶凋落物之间C/N和C/P的差异逐渐减小,分解末期分别趋近于23和350. 随有机物剩余百分率的降低, N/P变化不明显,当有机物剩余百分率低于25%时,不同树种叶凋落物之间N/P差异显著下降. 有机物剩余百分率可用来预测C、N和P的剩余百分率.   相似文献   
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