逊别拉河流域湿地种子植物组成及区系地理成分分析

逊别拉河流域湿地种子植物共有71 科218 属461 种,植物区系组成中最大科是菊科,其次为毛茛科、禾本科和莎草科;除世界分布科外,温带分布科占第一位;属的地理成分中以北温带(含变型)占优势,有102 属,占总属数的62.04%;种的区系以温带成分(74.15%)占绝对优势.区系特征表现为:优势科现象明显,单种属和寡种...     

黑龙江省细鳞河国家级自然保护区种子植物区系研究

为进一步了解黑龙江细鳞河国家级自然保护区种子植物区系特点,通过实地调查并结合文献资料,对保护区内种子植物的种类组成及区系成分进行了研究与分析。结果表明,保护区内共有种子植物81科274属529种,其中裸子植物1科4属6种,被子植物80科270属523种。大科及较大科共13科,占总科数的16.05%,包含种数达313种,占总种数的59.17%,优势科现象明显。保护区内种子植物区系成分中,属级温带成分占比88.39%,种级温带成分占比90.16%。该保护区内种子植物分布型以温带成分占优势,与寒带及热带有少量交流,整体区系体现出强烈的温带性质。     

黑龙江兰远草原自然保护区种子植物组成及区系地理成分分析

黑龙江兰远草原自然保护区种子植物共有53科177属363种,植物区系组成中最大科是菊科,其次为禾本科和莎草科;除世界分布科外,温带分布科占第1位;属的地理成分中以北温带(含变型)占优势,有69属,占总属数的51.49%;种的区系以温带成分(79.69%)占绝对优势.区系特征表现为:优势科现象明显,单种属和寡种属占据比率较高;地理成分优势性显著,来源较广泛.     

上海市海岛种子植物区系特征分析

上海市海岛共有种子植物314种,隶属于206属69科,其科包含6种分布型,属包含15种分布型。通过对上海市海岛种子植物区系的组成、地理成分、区系特征进行分析,得出主要结论如下：植物区系组成复杂、地理成分多样;广布性成分比例高、呈现出从热带向温带过渡的趋势;滨海植物区系丰富。     

松嫩平原大庆地区 种子植物区系多样性分析

探究了松嫩平原大庆地区种子植物区系多样性及基本特征。根据野外实地考察,初步统计到大庆地区种子植物共有64科212属393种,其中大科(21种以上)占有最大比例(45.29%),单种科数量最多且种数最少;从属的区系成分来看,温带成分占主导(73.46%),并出现了特布现象,说明该区域在植物演替、发展过程中具有一定程度的间断性;生态类型划分显示中生植物占主导(52.66%),旱生植物次之(21.77%),说明植被保留有明显的以中生植物为主体的草原植被特征。为松嫩平原大庆地区植物资源的保护和管理提供基础资料和理论依据。     

温带山地植物区系比较分析

为了揭示温带不同山地之间植物组成的相互联系,以长白山、海棠山和百花山自然保护区的植物名录为数据源,对三个山地植物区系的物种组成、地理成分进行统计分析,并采用Jaccard系数和Ze-hanowski系数,对三个山地间植物区系的相似性进行对比研究。结果表明:长白山与海棠山科、属、种的Jaccard系数分别为55.0%、34.1%和14.7%,Ze-hanowski系数分别为70.9%、50.9%和25.6%;长白山与百花山科、属、种的Jaccard系数分别为69.3%、45.8%和22.0%,Ze-hanowski系数分别为81.9%、62.8%和36.0%;海棠山与百花山科、属、种的Jaccard系数分别为56.2%、42.0%和14.6%,Ze-hanowski系数分别为72.0%、59.1%和25.4%,表明三个山地间植物区系有一定关联,其环境和自然演化史具有共同性特征。     

大兴安岭呼玛县五味子分布区种子植物区系分析

五味子(Schisandrachinensis)为五味子科多年生木质藤本植物,是我国重要的中药材之一,在我国最北分布于大兴安岭呼玛县境内的呼玛河流域及黑龙江沿岸沟谷;其分布区有种子植物60科167属317种;该区系地理成分较复杂,具有14个种子植物属的分布类型,其中属温带分布成分的132个属占总属数的79.04%,为植物组成的主体,形成了与大兴安岭其他地区植物区系特征的差异,表明与五味子在其他分布区的植物区系的联系性。     

扎龙国家级自然保护区的种子植物区系研究

扎龙保护区共有种子植物５２６种,其植物区系是温带性质,组成较丰富,地理成分较复杂。地理联系广泛;属世界分布的植物多。深受华北植物区系的影响,并无特有种。扎龙保护区植物组成中长白植物区系成分占２９．８４％,华北植物区系成分占２７．３２％,蒙古植物区系成分占２３．３３％,大兴安岭植物区系成分占１９．５１％,反映出植物区系组成的混杂性。     

三江平原洪河自然保护区植物多样性研究Ⅰ水冬瓜-丛桦-小叶章沼泽化草甸

水冬瓜-丛桦-小叶章沼泽化草甸是三江平原洪河国家级自然保护区草甸植被的重要类型之一;组成植物62种．隶属于28科45属。其中温带分布属27个．占65．85％,以长白、大兴安岭植物区系成分为主;生活型谱以草本地面芽和地下芽植物占优势。     

三江平原地区杂类草沼泽的植物区系研究

通过对三江平原的野外调查,统计出三江平原杂类草沼泽植物组成中含种子植物47科92属173种。三江平原地区杂类草沼泽的种子植物区系是东亚植物区系北部一个植物区系,该类沼泽植物区系是温带性质,但有较多温带性质的种分布中心偏北,表现了寒温带的特点。     

沂蒙山区的蜜源植物

沂蒙山区主要蜜源植物有 1 3科 ,1 8种 ;辅助蜜源植物有 63科 ,1 46种 ;有毒蜜源植物 2科 ,2种。介绍了其分布、保护和开发利用状况     

水生植物清理工程对越冬鸟类种群的影响

为了给越冬鸟类营造适宜的栖息环境,泗洪洪泽湖湿地国家级自然保护区对核心区水生植物进行了清理,并对清理前后区域内水质、水生植物数量、种类以及鸟类数量、种类进行了调查。结果显示：水生植物清理前,研究区仅观察到约30只越冬鸟类,且均为绿头鸭;水生植物清理后,调查到7种鸟类,隶属2个目2个科,约有9000只,其中数量最多的为绿头鸭Anser platyrhynchos,隶属雁形目鸭科,其次为白骨顶Fulia atra,隶属于鹤形目秧鸡科。在调查过程中还发现了国家稀有物种震旦鸦雀Paradoxornis heudei。     

中国的野生植物所有权制度与野生植物权属管理

中国长期以来没有建立起完善的野生植物所有权法律制度,只是在专门性行政法律法规中规定单位和个人开发利用和经营管理野生植物资源的活动受到保护,并规定对受保护的野生植物的权属进行管理。《物权法》实施后,立法机关应根据《物权法》对《森林法》及其实施条例、《野生植物保护条例》的有关条款修改,对野生植物所有权及权属管理制度做出明确而系统的规定,协调好野生植物开发利用与生态保护之间的关系。     

小陇山林区百合科观赏植物资源及其园林应用

小陇山地处温带南缘与北亚热带的过渡地带,气候温和湿润,适宜林木繁衍生长。作为我国华北、华中、喜马拉雅、蒙新四大自然植被区系的交汇处,植物种类繁多,是温带向亚热带过渡的植物基因库。通过多年的野外实地调查和文献研究,发现该地区约有百合科野生观赏植物23属55种,从资源分布、生态习性、观赏特性、栽培要求等方面对这些植物进行介绍,并对其园林应用做出分析建议。     

Do native and invasive labels affect consumer willingness to pay for plants? Evidence from experimental auctions

Ornamental plant sales have been identified as an important vector for the introduction of invasive plants. Increased concerns about the economic and ecological costs of invasive plants have spawned interest in identifying strategies to curtail introductions. One possible strategy is labeling plants based on whether they are invasive or native. The primary purpose of this paper was to explore how labeling plants based on invasive and native attributes might affect consumer demand. To accomplish this objective, a second price auction was used to elicit the willingness to pay (WTP) for plants with and without labels. On average, we found a $0.35 premium for plants labeled as noninvasive and native and a $1.01 to $1.66 discount for plants labeled as invasive. The size of these premiums and discounts differed in relation to various demographic, attitudinal, and preference‐related factors. Overall, our results suggest that labeling plants as invasive or native could be a viable strategy for reducing the introduction of invasive plants.     

Relationships between absenteeism,conservation group membership,and land management among family forest owners

Absentee landowners, or those who do not live on their forestland, own approximately 117 million acres of private forestland in the U.S. Thus, their land management decisions and activities influence the flow of forest-based goods and services. We explore the question of whether absentee family forest owners are less active land managers than resident landowners and whether membership in conservation organizations is associated with higher levels of land management activity by absentee owners. To examine these questions, we administered a mail survey to randomly-selected family forest landowners in Indiana. While we found some support for the contention that absentee owners are less active forestland managers than resident owners, we also found they are not necessarily inactive landowners. We found absentee owners were less likely to have: inspected their forestland for invasive plants, pulled or cut invasive plants, used herbicides to kill invasive plants, reduced fire hazard, or grazed livestock than resident owners. Absentee owners were more likely to be enrolled in the Indiana Classified Forest and Wildlands Program, a preferential forest property tax program. Absentee owners who are members of a conservation organization were more likely than absentee non-member owners to have undertaken a variety of land management activities, including: undertaking wildlife habitat improvement projects, inspecting their forestland for invasive plants, pulling or cutting invasive plants, enrolling in the Indiana Classified Forest and Wildlands program, and obtaining a management plan.     

黑龙江省森林植物园野生乡土园林植物利用评价

对黑龙江省森林植物园野生乡土园林植物资源进行了实地调查,植物园有观赏价值的野生乡土园林植物133种,根据特点将其分为观赏蕨类、乔木类、灌木类、藤本类、草本类;对其中观赏特性及开发利用价值突出的植物进行重点描述,对该区野生乡土园林植物资源的开发利用提出了建议。     

An Approach to Examining Relative Efficiency in the Canadian Livestock Slaughtering Industry

In order to identify possibilities for enhancing economic efficiency, levels of relative performance in subsectors of the Canadian livestock slaughtering industry are examined. A variant of the transcendental logarithmic profit function is used to compare relative economic, technical and allocative efficiency between groups of plants of different size, and groups of plants with different degrees of product specialization. Large plants are found to be more technically efficient than small plants, and plants producing both fresh and processed products are found to be more technically efficient than those producing only fresh products. All categories of meat processing plants are found to be relatively and absolutely allocatively efficient. Further research is necessary at an individual firm level to establish specific efficiency characteristics. Afin ?identifier les possibilités ?accroissement de ?efficacité économique dans ?industrie canadienne de ?abattage, les niveaux de performances relatives des sous-secteurs sont analysés. Une variante de la forme logarithmique transcendantale de la fonction de profit est utilisée afin de comparer ?efficacité relative, technique et allocative entre groupes ?abattoirs de différentes tailles et de différents degrés de spécialisation. Cette comparaison montre que les abattoirs de grande taille sont techniquement plus efficaces que ceux de taille modeste. Les abattoirs mettant en marché à la fois des produits frais et transformés sont techniquement plus efficients comparativement aux abattoirs spécialisés dans le produit frais. Toutes les catégories de transformateurs sont relativement et de façon absolue allocativement efficients. Une recherche plus poussée est nécessaire afin ?établir les caractéristiques ?efficience individuelles.     

密山县野生维管植物资源的研究

报道了密山县植物资源的初步调查结果．计有维管植物９９科、 ２３０属、 ５７２种;对各类经济植物进行了分析和阐述、提出了一些具有开发利用价值的种类。     

A first-phase screening method for site selection of large-scale solar plants with an application to Italy

Increasing the exploitation of renewable energy sources (RES) is a key element for reducing the detrimental consequences of greenhouse-gases emissions and for satisfying the growing demand for energy. Solar power plays a central role having the potential to completely satisfy the world energetic needs. Locating optimal sites for installing solar plants is therefore an important task deeply affecting the long term profitability of such plants. The present paper proposes a filtering method to select a subset of efficient locations in order to reduce the dimensionality of the original problem when a large territory is screened for locating optimal sites for large-scale solar plants. It is based on the idea of preference relations and Pareto dominance and, avoiding to operate an inter-comparison of different locations’ attributes, it can be considered assumptions-free. Moreover, the paper applies such filtering method, together with an analysis of economic viability, to Italy, a country with relatively high potentials in terms of solar energy that currently lacks an optimal site selection analysis. Once applied, the filter reduces the original set of feasible locations by more than 99%. The resulting Pareto efficient locations, evaluated through five selected criteria, are concentrated in the southern part of Italy and, particularly, in the islands of Sicily and Sardinia, where also the economic viable locations are mostly found.