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1.
The newly formed extensive flooded land associated with the Three Gorges Reservoir hold great potentials to provide ecosystem services (ESs) for surrounding cities and communities. Conflicting values and conventional management strategies may complicate and inhibit broad-scale decision-making for this novel ecosystem. Public attitudes are a crucial influence in the way this process plays out. This study was conducted to assess how the reservoir bank is perceived by the general public of Chongqing Municipality in terms of importance of riparian ESs, and preference for corresponding landscape design styles through photo-questionnaire interviewing. Although Chongqing citizens know little of the “ecosystem services” concept, they do recognise riparian environmental and ecological benefits especially the bank protection and pollution interception functions, while benefits of habitats for wildlife and flood attenuation were of less concern. Recreational values were least appreciated, which is inconsistent with other studies. This may be attributed to a wider, intensive environmental education in various social media in today’s China. But publicity has been dominated by toxic air, water and soil pollution control rather than the benefits of nature conservation and personal contact with nature. In line with recognition of ESs, there is quite strong preference for the forested design scenario and particularly vegetation components across the socio-demographic spectrum. Overall, socio-demographic variables have very low explanatory power for the perceptual responses. Our study also revealed misunderstandings around riparian functions and a gap between public expectations and special abiotic and biotic prerequisites in restoring novel ecosystems. Finally, we discuss the relevance of this research to urban novel ecosystems in general, and implications for raising public awareness, engaging appropriate public values in sustainable design and management of such ecosystems. 相似文献
2.
阜康荒漠绿洲土地利用景观格局受自然分异和水土资源开发利用程度的制约 ,通过划分景观样带和选取景观空间格局指标 ,本文重点揭示该区域景观格局的变化及其影响因子。结果表明 :( 1 ) 1 987年至 1 998年间阜康土地利用景观格局变化主要表现为耕地面积在洪积扇上增加 ,在冲积平原上下降 ;荒地则刚好相反。林地面积在低山丘陵带和洪积扇带下降 ,在冲积平原上没有变化。牧草地面积在低山丘陵带上升 ,其他各带均下降。城镇面积在各样带上都有所增加 ,水域各带基本不变。 ( 2 )低山丘陵带和洪积扇带景观多样性和均匀度下降 ,优势度上升 ;而冲积平原则多样性和均匀度上升 ,优势度下降。景观破碎度有增加的趋势 ,表明了人为影响的不断增强。 相似文献
3.
百脉根单株产量主要农艺性状的相关和通径分析 总被引:3,自引:0,他引:3
通过对百脉根单株的11个农艺性状的相关分析,结果表明:分枝长度(X2)、分枝节间数(X3)、分枝茎粗(X4)、侧枝数(X6)、侧枝长度(X7)、侧枝节间数(X8)、侧枝茎粗(X9)对单株产量(Y)的作用达到极显著水平,分枝数(X1)、自然高度(X11)与单株产量的相关性达到显著水平,而分枝叶柄长度(X5)、侧枝叶柄长度(X10)则与产量的相关性不显著.通径分析结果表明:各性状对产量的直接效应从大到小依次为:分枝长度(1.121 6)>分枝节间数(0.346 3)>侧枝长度(0.114 6)>分枝数(0.106 4)>分枝茎粗(0.084 6)>侧枝节间数(0.034 2)>侧枝茎粗(0.028 9)>侧枝数(0.021 6)>侧枝叶柄长度(-0.043 6)>分枝叶柄长度(-0.065 4)>自然高度(-0.748 2). 相似文献
4.
Landscape modeling requires the delineation of system boundaries and interior features. Quite often, these components are
complex and difficult to accurately represent. A rectangular grid is used to represent the study and adjacent non-study areas
in most cases. When the non-study area occupies a large portion of the grid, computer memory is wasted, and computational
time increases. An elliptical grid generator for non-orthogonal curvilinear coordinates is used to generate a boundary-fitted
grid for a landscape model. In a boundary-fitted grid coordinate system, one coordinate axis follows the landscape domain
boundary and is non-orthogonal to the second axis. The boundary-fitted grid uses elliptic partial differential equations to
distribute grid points inside the landscape domain. Although the boundary-fitted grid follows the domain boundary, the grid
pattern and point allocation remain structured. Thus, a landscape model can use a boundary-fitted grid without changing the
model’s data structure or the computational scheme. In this study, a boundary-fitted grid and a raster-based grid were applied
to the Everglades Landscape Fire Model. Use of the boundary-fitted grid decreased model simulation time by about one fifth
and computer storage by 58% relative to the raster-based grid. Also, the linear characteristics of interior geographical features
such as rivers and airboat trails were preserved by the boundary-fitted grid, but not by the raster-based grid. This preservation
provided a more reasonable base map for simulating ecological processes, such as fire across heterogenous landscapes. 相似文献
5.
Dai Huaguo Song Xiaoling Nanjing Agricultural University Li Jianlong Northeast Forestry University 《林业研究》1993,(2)
Through rearing tests and observations under laboratory conditions,biologicalcharacters and mating behavior of Dahurian casebearer(Coleophora dahurica Flkv.)adultswere studied in this paper.Results discovered that the time of emergense of male adultswas 24h to 36h earlier than that of female adults.The peak of sex pheromone secretion ofthe female adults appeared of 24h to 42h after the emergence.The reaction of male adultson the sex pheromone was most sensitive during 30h to 48h after emerged,so the earlieremergence of the male adults was favorable to mating.The phenomenon of repeatedmating did not exist in female adults,but the male adults could mate for several times,with maximum of 4 times.There was a definite behavioral reaction during the matingperiod of male and female adults,and the certain period of feeding and mating times couldaffect the adults longervity to a certain degree. 相似文献
6.
本文综述了硝酸还原酶与氮素利用的关系及其遗传特性和在作物育种中应用的某些最新进展。氮吸收、利用等性状的生理和遗传特性极其复杂,受环境影响很大,对其进行遗传改良需考虑多种指标。对硝酸还原酶活性(NRA)与品质性状和产量的关系的争论很多,有些研究表明 NRA 可作为品质、产量性状的选择指标,有些则相反。逆境条件下 NRA 的变化非常敏感,NRA 可能与抗逆性有关。 相似文献
7.
8.
近年来,我国的景观植物产业得到了很大发展,但仍存在很多问题,为了解决这些问题,我们开发了景观植物信息查询系统(简称LPIIS)。LPIIS的构建包括后台数据库和管理系统2部分,以Microsoft Access开发后台景观植物数据库,实现各种零散的景观植物数据资料的数字化;采用面向对象的开发语言VB进行信息系统的界面设计和系统集成,实现了人性化的界面,操作更为方便。LPIIS的出现改变了过去景观植物信息管理的手工方式,具有可视化人性化的界面、提供多媒体信息、数据的维护和更新具有继承性、后台数据库可方便的移植于网络等特点。 相似文献
9.
10.