种子大小在森林更新过程中的生态学意义

就种子大小与个体发育、种群动态和群落组成、结构与动态的相互关系进行综述,着重阐述了不同大小的种子在个体发育过程中的生态学意义。     

Eco-environmental benefit assessment of China''''s South-North Water Transfer Scheme——the middle route project

IntroductionInordertoalleviateseverewatershortagesinnorthChina ,ChinesecentralgovernmenthavestartedtoimplementtheSouth NorthWaterTransferScheme(SNWT) ,whichwilltransferwaterfromYangtzeRiverbasininthesouthtoHuang Huai Hai(YellowRiver ,HuaiheRiverandHaiheRi…     

Spatial analysis of plant detritus processing in a Mediterranean river type: the case of the River Tirso Basin,Sardinia, Italy

The river continuum concept represents the most general framework addressing the spatial variation of both structure and function in river ecosystems.In the Mediterranean ecoregion,summer drought events and dams constitute the main sources of local disturbance to the structure and functioning of river ecosystems occurring in the river basin.In this study,we analysed patterns of spatial variation of detritus processing in a 7th order river of the Mediterranean ecoregion(River Tirso,Sardinia0Italy)and in three 4th order sub-basins which were exposed to different summer drought pressures.The study was carried out on phragmites australis and Alnus glutionsa leaf detritus at 31 field sites in seasonal field experiment Detritus processing rates were higher for Alnus glutionsa than for Phragmites australis plant detritus.Processing rates of Alnus glutionsa leaves varied among seasons and study sites from 0.006d^-1 to 0.189d^-1 and those of Phragmites australis leaves ranged from 0.0008d^-1 to 0.102d^-1,with the lowest values occurring at sites exposed to summer drought.Seasons and sites accounted for a significant proportion of such variability.Alder detritus decay rates generally decreased with increasing stream order,while reed detritus decay rates generallyincreased on the same spatial gradient.Summer drought events affected these spatial patterns of variation by influencing significantly the decay rates of both plant detritus.The comparisons among and within sub-basins showed strong negative influence of summer drought on detritus processing rates.Similarly,in the entire River Tirso basin decay rates were always lower at disturbed than at undisturbed sites for each stream order;decay rates of reed detritus remained lower at those sites even after the end of the disturbance events,while alder decay rates recovered rapidly from the summer drought perturbations.The different recovery of the processing rates of the two leaves could also explain the different patterns of spatial variation observed between the two leaves.     

浅谈生态平衡的破坏和重建

通过列举古今中外实例 ,从生态学角度 ,阐述生态平衡的重要性及深远意义 ,警示世人大自然法则不容破坏 ,保护和重建生态平衡就是保护人类的生存与发展。     

生态系统调节水量的价值评估——兴山实例

根据植被类型、坡度和土壤类型，分析了兴山县集水区内不同植被地块调节水量的能力。并且根据水能学的原理，分析了枯水期和洪峰期葛洲坝水电站的发电量与水流量的关系，建立了水流发电模拟模型。在上述分析的基础上，评估了兴山县境内生态系统调节香溪河等河流的水量，改善长江全年来水的均匀度，提高葛洲坝水电站发电效率的经济价值。     

生态治理工程对锡林郭勒草地生态系统文化服务感知的影响研究

锡林郭勒近年来草地退化趋势严重,一系列生态治理工程陆续开展。基于问卷调查法,探究草地文化服务牧户感知情况及其影响因素,对比分析不同治理工程区牧户对草地文化服务感知的差异。结果表明：（1）牧户对草地文化服务的感知受其民族、年龄、文化水平的影响（P<0.05）。蒙古族对生理和精神健康、美学价值的感知高于汉族;年龄较高的群体对生理及精神健康服务、教育及研究价值感知较高,对休闲娱乐的感知较低;高文化水平群体对教育及研究价值感知较高。（2）生态工程影响草地文化服务的牧户感知,“草畜平衡+休牧+禁牧”区牧户对草地多项文化服务（生理及精神健康、灵感、精神及宗教信仰、地方感、休闲娱乐）的感知低于其他治理工程区。     

黑龙江省生态功能区划研究

在生态环境现状评价、生态环境敏感性评价、生态系统服务功能重要性评价基础上,根据区划原则,采用定性和定量分区相结合的方法,将黑龙江省划分成6个生态区,13个生态亚区,45个生态功能区,并且给出各类重要生态功能区的数量、位置和面积.     

The ecosystem and autonomy: A reconsideration of the ecosystem concept (I)

A critical review of the development of the ecosystem concept is presented in this paper. An attempt to define the concept is discussed in details with reference to autonomy.     

洞庭湖区灾后重建的流域生态管理学思考

洞庭湖中上游水土流失加剧,导致湖区调蓄能力下降,垸高田低,灾害频率上升。为抗御洪水,堤防越筑越高,造成洪水位抬高等副作用。对此,提出流域生态管理对策：①将长江流域生态安全列为国家安全战略体系的重要内容之一；②将非蓄洪性质的围垦调整为蓄洪性质的围垦,正常年份耕种,大洪水时用其蓄洪；将封闭式围垦种植改造成为半封闭型的养殖与留湖调蓄；③环境移民城镇安置,缓解人口对土地、湖泊的压力；④进行避洪、耐渍型生态设计,建立适应水体、湖洲和低湖渍害田的复合高效生态工程；⑤调整丘岗地利用结构与重建山区植被是减灾的治本措施。量大、面广的水土流失发生在丘陵坡地     

What Matters Most: Are Future Stream Temperatures More Sensitive to Changing Air Temperatures,Discharge, or Riparian Vegetation?

Simulations of stream temperatures showed a wide range of future thermal regimes under a warming climate — from 2.9°C warmer to 7.6°C cooler than current conditions — depending primarily on shade from riparian vegetation. We used the stream temperature model, Heat Source, to analyze a 37‐km study segment of the upper Middle Fork John Day River, located in northeast Oregon, USA. We developed alternative future scenarios based on downscaled projections from climate change models and the composition and structure of native riparian forests. We examined 36 scenarios combining future changes in air temperature (ΔT_air = 0°C, +2°C, and +4°C), stream discharge (ΔQ = ?30%, 0%, and +30%), and riparian vegetation (post‐wildfire with 7% shade, current vegetation with 19% shade, a young‐open forest with 34% shade, and a mature riparian forest with 79% effective shade). Shade from riparian vegetation had the largest influence on stream temperatures, changing the seven‐day average daily maximum temperature (7DADM) from +1°C to ?7°C. In comparison, the 7DADM increased by 1.4°C with a 4°C increase in air temperature and by 0.7°C with a 30% change in discharge. Many streams throughout the interior western United States have been altered in ways that have substantially reduced shade. The effect of restoring shade could result in future stream temperatures that are colder than today, even under a warmer climate with substantially lower late‐summer streamflow.