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1.
Considerable research has examined the social, cultural, economic, and community benefits of urban gardening. Few studies, however, have empirically assessed factors that influence urban community garden agrodiversity or its relationship to these dimensions of gardening. We conducted an interdisciplinary study of agrodiversity and cultural identity, based certain markers of identity, including how people see themselves with respect to race, ethnicity, or place of origin, in community gardens in Philadelphia, Pennsylvania. We conducted fifty‐six semistructured interviews with gardeners with different cultural identities in eight community gardens on their motivations for urban community gardening during 2014. We conducted plant inventories of the corresponding garden plots and found 104 cultivated edible and ornamental species and 28 varieties representing 34 families. We find that although gardens with culturally diverse gardeners did not have higher species richness, the cultural identity of the gardeners influenced species selection and reason for gardening. Further, the structure, design and species composition of garden plots reflected the identities of garden members. These finding have implications for the recent institutionalization of urban agriculture into city land policies in Philadelphia and other cities in North America.  相似文献   

2.
Horticultural and gathering practices were studied in Comallo and Pilcaniyeu, two semi-rural communities which share a common Mapuche ancestry and occupy similar arid environments in Northwest Patagonia, Argentina. We analyzed cultivation and wild plant gathering using semi-structured interviews. We hypothesized that these activities will be conditioned by access to market economy. Results showed differences in horticultural and gathering patterns in both populations: the community with less access to market economy presented greater richness of cultivated and gathered species and collected more seeds from their own harvests, thus promoting germplasm conservation and higher levels of seed exchange than the community that had more contact with urban centers. In these populations the integration of ancestral and novel knowledge seems to favor flexibility and autonomy, which might help locals deal with change. This could foster greater individual and collective wellbeing, as well as socio-ecological diversity.  相似文献   

3.
About 52% of the world's population now lives in urban areas, and 41% of urban land in developed countries is used for residential areas. The amount and quality of residential green space, an important element in urban residential infrastructure, is closely correlated to city dwellers' quality of life. The quality of green spaces is not only closely correlated to the ecosystem services they provide, but also to their disservices. In order to (i) examine how plant diversity and plant traits vary in different residential areas, (ii) determine the main socio-economic factors driving plant trait variations across different residential areas, and (iii) provide an overview on selected ecosystem services and disservices related to plant diversity, we investigated the flora and socio-economic properties of 83 residential areas in Beijing, China. We found a total of 369 plant species belonging to 99 families and 150 genera. With respect to plant traits, there were 90 annual species, 174 alien species, 169 pollen allergenic species, and 133 species with edible or pharmaceutical value. The number of perennial, alien, ornamental and edible plant species was largest in residential areas completed in the 1990s. The number of allergenic species was highest in residential areas completed prior to 1980. The Simpson, Shannon and Pielou indices for trees and shrubs were highest in areas completed in the 1990s, while those same indices for herbs were highest in residential areas completed prior to 1980. General Linear Model analyses revealed that richness increased with increasing housing price across all groups of species. Principal Component Analysis indicated that housing price and floor-area ratio are the variables that positively correlate with species richness for all groups of species.  相似文献   

4.
ABSTRACT

The Kandyan homegardens, or forest gardens, of central Sri Lanka are diverse, smallholder agroforestry ecosystems that for 2000 years have reflected evolving environmental, economic, and social livelihood needs. An ecosystem services approach interrogated homegarden changes over the last 10 years in 31 Kandyan households. Livelihood strategies favouring homegardens were found to have broader benefits across household, national, and global scales than those favouring commercial simplification or those abandoning cultivation for alternative incomes. Livelihood benefits beyond income included resilience to economic and environmental shocks; food security; and higher stocks of biological and agricultural diversity. This revealed overlooked socio-ecological feedbacks between drivers that frustrated interventions to sustain homegarden livelihoods, including increased wild animal incursions thwarting household climate adaptation and disaster recovery; global organic and fair trade incentives reducing food security and livelihood resilience; and national seed and animal regulations counteracting homegarden sustainability programs. Despite these pressures, households maintained homegarden systems for their cultural, aesthetic and eating preferences. An ecosystem services approach can complement sustainable livelihood approaches by identifying overlooked environmental and cultural benefits; reveal livelihood feedbacks from drivers of ecosystem change; avoid unintended consequences from interventions; and capitalise on synergies between stakeholder priorities.  相似文献   

5.
Despite its economic and symbolic importance in the arid regions of the Middle East little is still known about the early cultivation of the date palm (Phoenix dactylifera L.). Besides its numerous uses, this fruit tree constitutes the main species and structural element of the date palm gardens that characterize the hot deserts of the Old World. These agrosystems, perfectly adapted to the specific constraints of the environment, concentrate agricultural production in an artificial and intensively cultivated space depending on irrigation. While the first evidence of the cultivation of date palms in southern Mesopotamia dates to the 5th millennium B.C., oasis agriculture seems to have developed mainly during the early Bronze Age (from around 3000 B.C.) when this type of agrosystem can be reconstructed in different parts of the Middle East: Mesopotamia, southeastern Iran and eastern Arabia. The present paper draws together evidence from different kinds of sources (archaeobotany, texts, iconography) bearing on the early history of oasis agriculture. Questions of particular interest are the organization of past date palm gardens and their irrigation.  相似文献   

6.
The present study aims to use landscape heterogeneity as a predictor of plant species richness in a tropical dry landscape area in the coast of Michoacán, Mexico. To understand the relationship between species richness and landscape, a three-step approach was followed: first, landscape spatial heterogeneity was measured by classifying landscape types according to their attributes (i.e., environmental, soil and topographic variables). Second, several diversity standard indices were used to explore biological diversity and to select the best one explaining the relationship between landscape heterogeneity and plant species richness, for this study area. Third, from the obtained results it was possible to calculate biodiversity values on the basis of landscape heterogeneity. The results indicate that it is possible to predict more than 61% of species richness through an indicator of landscape heterogeneity (H′; Shannon–Weaver diversity index). This procedure may be useful in terms of land use, conservation, and management of protected areas, mainly in areas with high biodiversity but with limited biological data, since it allows to obtain an approximation of the spatial distribution of species richness, even with scarce biological information.  相似文献   

7.
ABSTRACT. This article examines how peasant farmers build and maintain agrobiodiversity in home gardens found in two traditional peasant communities along the Marañón River in the Peruvian Amazon. Data were gathered through household and garden surveys as well as in‐depth interviews with garden tenders in an upland mixed agricultural village and a lowland fishing village. Substantial variations in cultivated plant diversity were encountered in gardens between and within the villages, which are found to be related to differential exchange of seeds, cuttings, suckers, and other planting material as well as to specific garden and household characteristics. Planting material flows along multiple pathways—from gift giving and purchase to inheritance and scavenging—to the gardens, reflecting a complex and often extensive network of exchange that enables the establishment and maintenance of home garden plant diversity in seemingly isolated and small communities. Further research is needed to identify broader geographical and sociocultural patterns of agrobiodiversity in Amazonia.  相似文献   

8.
秦巴山地植物南北变化与过渡模式研究   总被引:1,自引:0,他引:1  
秦岭—大巴山是中国重要的南北地理分界线和生态过渡带,建立秦巴山地南北方向上植物种类组成及重要值的详细变化序列和过渡模式,对于深入认识中国南北过渡带的过渡性、复杂性及暖温带与亚热带分界线具有十分重要的科学意义。本文通过野外实地调查获取秦巴山地东、中、西部3条南北穿越样线163个采样点的植被序列数据,分析了物种丰富度、相对重要值及优势种多度的纬向变化,并将亚热带与温带物种相对重要值的差值(SND-RIV)用于表现南北方物种的优势程度,以分析和归纳植物的空间变化模式。结果表明:① 东部(三门峡—宜昌)、中部(西安—达州)、西部(天水—广元)亚热带物种丰富度及相对重要值自北向南递增,温带物种自北向南递减。东部温带物种丰富度及相对重要值在神农架和伏牛山由于海拔高度的影响出现两个峰值,中部亚热带物种在大巴山地区最高,西部亚热带物种在陇南以南超过温带物种;② 东部南北方物种的交错过渡带最宽,约180 km;中部大约在秦岭南坡至大巴山北坡之间,约100 km;西部交错过渡带偏南,约50~60 km。③ 东、中、西部山地植物纬向过渡模式和驱动因子有明显差异。东、西部自南向北亚热带物种的减少主要与年均降水量减少有关,年平均气温影响较小;中部年平均气温的作用比湿润指数稍大。本文揭示了秦巴山地东、中、西部植物的南北变化及过渡模式,提升了对中国南北过渡带复杂性和多样性的科学认识。  相似文献   

9.
为研究岷江干旱河谷的豆科植物物种多样性及其在纬度和海拔梯度上的分布格局,在从四川汶川到松潘的干旱河谷两岸选择了7个地点,通过204个样方 (2 m×2 m) 调查,分析了不同纬度和海拔豆科物种组成、高度、盖度与根系结瘤的空间分布特点.结果表明:(1) 在所有样方中共出现乡土豆科植物16属,38种,其中灌木7属19种;草本植物7属17种,1或2 a生草本 6种,多年生草本11种.仅刺槐 (Robinia pseudoacacia L.) 和葫芦巴 (Trigonellae foenum-graecum L.) 为栽培物种.灌木在该地区豆科植物中占较大优势,50%以上灌木的频度与盖度均>10%,尤其白刺花 (Sophora davidii)、小马鞍羊蹄甲 (Bauhinia brachycarpa var.microphylla)、岷谷木蓝 (Indigofera lenticellata) 等灌木频度>20%,而所有草本植物的频率及盖度都<10%. (2) 豆科植物丰富度及生长具有较为明显的空间差异,干旱河谷核心地区的干热、贫瘠环境中,总物种丰富度较高,但是其盖度与高度较小.随着纬度升高,灌木丰富度和频度均减少,草本丰富度与和频度增加.随着海拔上升,灌木丰富度与总物种丰富度都减小,草本植物丰富度变化不明显;植物平均高度与盖度高度也无明显的垂直变化规律.(3) 植物根系结瘤能力很低,66%物种未结瘤,并且幼苗结瘤能力显著大于成株.这一结果可为豆科植物资源的保护和开发利用提供科学依据.  相似文献   

10.
ABSTRACT

Gardens in Australia are considered an important site of heritage maintenance and negotiation for their capacity to materialise transformations in everyday life, design, lifestyles, demographics, environment, as well as social and cultural practices. In the case of conservation areas, gardens tend to be valued in terms of their closeness and potential to preserve specific historical elements. Plants in these gardens are cultivated to evoke period designs, such as Federation (c.1890–1915) and cottage gardens. In this article we turn to gardens and gardening to make sense of entanglements between cultural, historical and environmental elements, and we ask: what role do plants play in shaping our understanding of suburban heritage? To answer this question, we draw on oral histories, archival research and ethnography in Haberfield, the first model garden suburb in Australia. We show how plants channel and mediate multiple concerns that contest and extend ideas of heritage circulating in public discourse. Foregrounding the centrality of plants, this article contributes a dynamic definition of heritage that includes the entanglement of environmental stewardship and individual and collective heritage.  相似文献   

11.
How species diversity–productivity relationships respond to temporal dynamics and land use is still not clear in semi-arid grassland ecosystems. We analyzed seasonal changes of the relationships between vegetation cover, plant density, species richness, and aboveground biomass in grasslands under grazing and exclosure in the Horqin Sandy Land of northern China. Our results showed that in grazed and fenced grassland, vegetation cover, richness, and biomass were lower in April than in August, whereas plant density showed a reverse trend. Vegetation cover during the growing season and biomass in June and August were higher in fenced grassland than in grazed grassland, whereas plant density in April and June was lower in fenced grassland than in grazed grassland. A negative relationship between species richness and biomass was found in August in fenced grassland, and in grazed grassland the relationship between plant density and biomass changed from positive in April to negative in August. The relationship between the density of the dominant plant species and the total biomass also varied with seasonal changes and land use (grazing and exclosure). These results suggest that long-term grazing, seasonal changes, and their interaction significantly influence vegetation cover, plant density, and biomass in grasslands. Plant species competition in fenced grassland results in seasonal changes of the relationship between species richness and biomass. Long-term grazing also affects seasonal changes of the density and biomass of dominant plant species, which further affects the seasonal relationship between plant density and biomass in grasslands. Our study demonstrates the importance of temporal dynamics and land use in understanding the relationship between species richness and ecosystem function.  相似文献   

12.
北固山湿地植物群落特征及其物种多样性研究   总被引:15,自引:4,他引:15  
北固山湿地位于镇江市东北,由长江携带泥沙长期沉积形成,植被属原生裸地演替,植物种类丰富。但近年由于污染排放及渔民围网捕鱼,植被受到破坏,生态功能被削弱。采用样方法调查了镇江北固山湿地植物群落的组成,种类和外貌,并分析了其物种的多样性差异,从而为湿地的生态修复提供理论和技术依据。试验结果表明:群落物种组成较为丰富,有15科28属33种,但仅限于草本植物,生活型以地面芽植物和一年生植物占优势,物种出现频度上以D、C两个级别为主,表明群落内物种的分布较为均匀。从季相动态上看,季相明显,群落的优势种2~4月前是虉草(Phalarisarundinacea)单优种群,4~6月是虉草-芦苇(Phargnitescommunis)共优种群,6~11月是芦苇-酸模叶蓼(Polygonumlapathifolium)共优种群。随着基底高程的变化,植物呈现明显的平行于堤岸的带状分布,并形成区别明显的三个区域。其中,物种的丰度、多样性指数、群落的均匀度以及生物量均随基底高程的增加而增加,而生态优势度却随基底高程的增加减小。物种多样性指数受立地环境和人为因素的共同影响。其中,一定程度的人为干扰虽降低物种丰度,但由于其对优势种芦苇破坏较为严重,降低了群落的生态优势度而相应提高了群落的均匀度,最终对物种多样性指数有增加效应。在以上研究的基础上,提出了禁止污染排放及围网捕鱼等措施,并在裸露或物种稀少区域人工栽培土著物种以增加湿地生态系统物种的多样性和稳定性。  相似文献   

13.
In this study we describe the biogeographic patterns of the endemic cacti from the Atacama Desert to the Mediterranean area of Chile. Our goals were: (1) to identify areas of high endemism, (2) to test Rapoport’s rule, (3) to test the geometric constraints hypothesis, (4) to explore temperature and precipitation as explanatory variables of species richness. We used a list of 72 species of cacti, ranging from 18° to 36° S and from 0 to 4500 m.a.s.l. A Bayesian analysis of Endemicity (BAE) was used to evaluate hierarchical relationships of endemism between different latitudinal bands. Rapoport’s rule was evaluated by examining the relationships between latitudinal/altitudinal mid-point, latitudinal/altitudinal range extent and species richness. The geometric constraints hypothesis was tested by examining the existence of mid-domain effect. The BAE indicated two areas of endemism: (1) the northern area between 18° S and 26° S, and (2) the southern area between 27° S and 36° S. The shape of the latitudinal gradient is non-linear, supporting the geometric constraints hypothesis. Altitudinal patterns, however, support Rapoport’s rule; a peak of endemism was found at low altitudes. The explanatory variables were elevation, minimum temperature of the coldest month, mean temperature of wettest quarter and annual precipitation.  相似文献   

14.
The intense urbanization of the Mediterranean coast as a result of the development of residential-tourist activities since the 1960s, especially from the mid-1990s to 2008, has generated new urban environments associated with extensive urban typologies. These include gardens linked to houses with outdoor spaces that are shared between all of the residents of the residential developments. The aim of this study is to determine the main characteristics of these new urban green spaces and their effect on domestic water consumption in Alicante (Spain). To do this, we analysed the characteristics that define these types of gardens (surface area, density, plant species and irrigation system) and determined their water needs using the Water Use Classifications of Landscape Species method. The main conclusions are that the increase in paved areas is one of the strategies to reduce water consumption in spaces where turf grass is the most common plant species. This is due to increased water prices and lack of water resources.  相似文献   

15.
16.
The Mapuche people have a deeply rooted tradition of wild plant use for their subsistence. In this study we evaluated whether plant selection by the Mapuche is influenced by environmental constraints. Selection patterns of wild plant richness were compared in two Mapuche communities sharing the same traditions and beliefs but inhabiting different environments. Similarities and differences in the use patterns of wild medicinal and edible plants were quantitatively analyzed by using concepts derived from ecological theory. The Cayulef community is settled in the NW Patagonian (herbaceous) steppe while the Curruhuinca community is established near the Andean temperate forest, 100 km away from each other. Free-listing and semi-structured interviews were conducted with 32 families in Cayulef and 39 in Curruhuinca corresponding to 80% and 40% of each population, respectively. Data were analyzed by means of the Jaccard similarity index and statistical tests. The main results of this study showed that the home environment is a determinant factor that influences which plant species are utilized, as is the anthropic environment (with its high exotic species richness) in each community. However, similar patterns were found with respect to plant families, ways of utilization, plant parts and life forms utilized irrespective of where the communities are settled. In addition, in both populations, wild plant richness was significantly higher for medicinal than for edible species. Our results showed that the use of wild plants is primarily based on the utilization of species belonging to the nearest ecological environments that have both therapeutic and dietary functions.  相似文献   

17.
Climate and grazing are the main drivers of plant community composition and species richness in arid environments. This study aimed to examine the vegetation response to a spatial precipitation gradient, interannual rainfall variability, and grazing pressure in Mongolia. To examine the effect of a spatial precipitation gradient, we compared species richness among six sites. To investigate the effects of interannual rainfall variability and grazing pressure, we compared species richness for 2 years at two sites, in desert-steppe and steppe areas. The regional gradient in annual precipitation showed positive and negative relationships with grass richness and shrub richness, respectively, although total species richness did not vary significantly. The proportions of the different functional groups were affected by grazing pressure and rainfall variability in both zones. In the desert-steppe zone, species richness was lower in the drier year but did not vary with grazing pressure. In the steppe zone, species richness varied significantly with grazing pressure but did not vary between years. Precipitation would be more important than grazing pressure on vegetation changes in drier areas with high rainfall variability.  相似文献   

18.
Warm deserts world-wide provide habitats for rich lizard species assemblages; North American deserts are no exception, however the desert regions of the US and Mexico are experiencing increasing habitat changes from multiple anthropogenic sources. Our objective here was to document current lizard species richness patterns across the North American deserts within the existing network of conservation areas. We identified 110 lizard species occurring across one or more of the 19 sites we analyzed. Three species richness hot spots were identified; a northern Baja California faunal extension into southern California in the US, and in Mexico, two sites within the state of Coahuila, as well as high endemism in the Cape Region of Baja California Sur. Species richness was associated with sites where desert ecoregions overlap and with insular isolation. Our uncertainty regarding how species will respond to the multifaceted aspects of global change is such that large protected natural areas with complex topography may be the most effective strategy for protecting desert lizards along with overall biodiversity. The 19 sites we analyzed represent the cores of a more robust conservation network that will be needed for the protection of biodiversity across North American Deserts.  相似文献   

19.
Medicinal plant cultivation and gathering can play a vital role in the course of livelihood diversification for the marginalized population living in remote areas. However, this requires an integration of the respective production networks that allows the producers a fair and reliable income and does not endanger rare plant species. This paper analyses the situation within the Indian state of Uttarakhand, and identifies structures and entities hindering medical plant cultivation and its potentials. Based on the broad network understanding of the Global Production Network approach, the case study focuses on the middlemen and their hidden embeddedness. It shows how governmental organizations and in particular non‐governmental organizations and farmers' institutions can help to overcome clandestine structures of illegal trade and contribute towards a redesign of the medicinal plant network in a more equitable and transparent way.  相似文献   

20.
Grazing effects on patchy dryland vegetation in northern Patagonia   总被引:1,自引:0,他引:1  
In this study the spatial patterns and dynamics of vegetation patches along a grazing gradient in the steppe ofLarrea divaricataandStipaspp. in NE Patagonia (Argentina) are described. A general effect of grazing is the reduction of total plant cover resulting from the decrease in cover of perennial grasses (Stipa speciosa, Poa ligularis, Stipa tenuis) and some tall shrubs (Chuquiraga hystrix, Bougainvillea spinosa, Lycium chilense). Dwarf shrubs (Nassauvia fueguianaandJunellia seriphioides) increase their cover under medium and/or high grazing pressures. Plant species are spatially grouped into patches which alternate with areas of bare soil. Eleven types of vegetation patch differing in the dominant plant functional type or species, floristic richness and size were identified with different relative frequency along the grazing gradient. Based on these results, it is postulated that grazing forces the replacement of large patches dominated by tall shrubs with high species richness, byLarrea divaricatapatches or small dwarf shrub patches with low species richness and the extinction of grass patches. This results from: (1) disruption of local balances of species deletions and additions; (2) fragmentation of large patches; and (3) formation of new vegetation patches. These changes lead to differing plant spatial organization and heterogeneity along the grazing gradient which may be described by characteristic arrays of vegetation patches.  相似文献   

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