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1.
Urban woodlands provide aesthetic experiences and recreational opportunities for people. The characteristics of vegetation are closely linked to these benefits. However, previous research has primarily focused on the effects of trees on aesthetic preference, while less research has involved the understory. This paper explored the relationship between understory characteristics and aesthetic or recreational preference. Twenty one images were rated for preference by participants (n = 184) on a five-point scale. Except for the original picture, these images were created using the photomontage method that manipulated understory height, the flowers and the path of the original picture. Results indicated that: (1) concerning aesthetic preference, all vegetated images were preferred more than the paved image, but for recreational preference, the paved image was preferred over the vegetated images; (2) the height of understory vegetation had a significant influence on aesthetic and recreational preference; (3) flowers and path increased aesthetic and recreational preference significantly. These results suggest that, in management of woodland, (1) maintaining the understory vegetation in middle height (0.5–1.0 m) or in full-mixed heights (low + middle + tall) (2) increasing shade-tolerance flowers and constructing a winding path in woodland would be preferred by the public.  相似文献   

2.
This paper explores the determining effect of the cognitive and affective antecedents of, satisfaction on the behavioural intentions of visitors to two suburban natural areas in Spain. Specifically, we examine the effect of psychological variables on willingness to pay for the, improvement of the conservation of the area and on visitor loyalty. Using multigroup invariance, analysis, we show how positive disconfirmation and positive emotions play a determining role, in the satisfaction formation process of visitors to the natural areas considered. We also show, that positive cognitive and affective experiences in visitors raise the economic valuation of the, conservation of a natural area and increase the likelihood of a prompt return visit. We discuss, the management implications deriving from the study of this cognitive and affective satisfaction, sequence in the environmental context, and demonstrate the usefulness of these behavioural, models combining economics with other social sciences in the environmental context.  相似文献   

3.
The willingness to pay can be considered as the fiscal dimension of equity in a planning context. The common solution in most western countries for such fiscal inequity is to apply taxation to rebalance; however, there is no equivalent tax category in China, where residential segregation has already occurred and intensified. This paper re-examines the traditional economic aspects of urban green space in relation to size, type and proximity level, and questions whether green fiscal equity appeared in China by exploring how homebuyers in different price ranges value green space services. Specifically, this paper uses the empirical case of Shanghai, China, to test the hypothesis via the quantile hedonic approach. The results show that people at the lowest percentile level paid a higher value for accessing urban public goods than people at the higher income percentiles, and that wealthy people prefer to purchase green space services privately. These results indicate that the traditional social equity problem may not appear in the Chines context, instead urban China’s problem with social quity may be more related to the privatisation of green space provision, which is only accessible to homeowners and the resulting decline of public green space developments, which primarily affects low-income renters.  相似文献   

4.
This study estimated the monetary value of urban forests’ non-priced benefits to tourists. Data collected by a face-to-face self-administered survey of urban tourists in Savannah, Georgia, USA were used to estimate tourists’ willingness to pay (WTP) for urban forests by the contingent valuation method. Individual WTP was found higher among tourists with graduate school education. Results suggested that WTP for urban forests also increased significantly with income and destination loyalty of the tourists. Estimated mean and median WTP values were $11.25 (95% confidence interval: $7.34, $15.16) and $2.10 (95% confidence interval: $1.38, $2.82), respectively. Based on the estimated mean WTP, annual value of urban forests to tourists in Savanna in 2009 ranged from a minimum of $81 million to a maximum of $167 million with a 95% confidence interval. The annual value was $11.55 million (95% confidence interval: $7.59 million, $15.51 million) based on the estimated median WTP and assuming at least 50% of the tourists in Savannah would pay the median amount. As the mean was greatly influenced by extreme WTP values in the data, the annual value based on the median value was a more conservative estimate.  相似文献   

5.
There has been a transformation of value orientation from an anthropocentric to eco-centric view in Chinese urban park design. Biodiversity enhancement has been increasingly seen as a prioritised park design aim by landscape designers. This promotes the rise of a novel park style with wild, less manicured appearance in cities, which shows strong contrasts to the traditional park style with ornamental, manicured characteristics. However, in this urban park transformation process, people’s opinion has been almost ignored. This research investigated the importance of biodiversity compared with other relevant urban park attributes (i.e., Facilities, Woodlands, Maintenance, and Seasonal views) identified from preliminary focus groups. The research further predicted preferences between wild and traditional urban parks. Conjoint analysis was used to address these questions. Five urban park attributes (i.e., Biodiversity, Facilities, Woodlands, Maintenance, and Seasonal views) were included in the conjoint questionnaire survey. The survey (N = 187) was conducted with the public and ecology/landscape professionals in Hangzhou, China. Results showed that for professionals, biodiversity was the most important attribute relative to others; for the public, both facilities and biodiversity were the most important attributes. Preferences for the two park styles varied between the two groups: professionals preferred wild parks, whereas the public preferred traditional parks. Yet, public preferences for wild parks were enhanced by improving maintenance levels and providing recreation facilities. The study concluded the appreciation of biodiversity among both the public and professionals. Differences in professional preferences for wild parks compared to the public should be considered when professionals design wild parks in the future.  相似文献   

6.
‘San Marzano’ (SM) is one of the most widely known tomato (Solanum lycopersicum L.) cultivars, and is a classic example of a local variety with a premium value. Unfortunately, the original cultivated form is underrepresented in the Protected Denomination of Origin (PDO) area because of the incidence of contaminant and phenotypically similar genotypes. Our aim was to examine the ability of three DNA marker systems (minisatellite, cleaved amplified polymorphic sequence (CAPS) and simple sequence repeat (SSR)) to reveal the genetic diversity of tomato accessions that were, based on a morphological analysis, very similar. The data indicate that both minisatellites and SSRs can be used to genetically distinguish the analysed materials. Furthermore, these two marker systems depict relationships consistent with the hierarchal pattern obtained by the morphological data. As locally cultivated tomato accessions are often characterised by some degree of genetic variability, our results will be valuable in facilitating the purification, management and breeding of tomato germplasms. The differences between the marker systems employed are also discussed in relation to their usefulness in the agro-food chain.  相似文献   

7.
Urban areas have increased greatly in recent decades, which has resulted in habitat loss. However, the promotion of urban green spaces could have a profound effect on biodiversity. Traditional fruit orchards are an important land-use type with the potential to host myriad organisms. Our goal was to determine the most important factors that influence orchard biodiversity in the million city of Prague (the capital of the Czech Republic). We used a multitaxon approach to evaluate the effect of orchard restoration in a landscape context. Restoration had a positive impact on species diversity, specifically, the diversity of orthopterans and butterflies. Moreover, landscape context determined the biodiversity of orthopterans, butterflies, and birds but not that of lichens. Our study underlines the importance of both the internal and external structures of traditional fruit orchards for species richness and composition. The results of our study support the restoration of traditional fruit orchards as a suitable management practice for promoting city biodiversity. Furthermore, orchard restoration can improve the attractiveness of suburban areas. Such areas often lack sufficient urban greening. Thus, restoration in these areas can also increase future recreational value.  相似文献   

8.
In tomato production, salt stress is applied to improve the fruit quality. The change in sensory attributes and organoleptic compositions in salt-stressed tomato fruits have been extensively studied; however, little is known about their interaction with each other. Correlation network analysis provides a visual representation of biological systems and useful knowledge for metabolic data analysis of tomato fruits. The aim of this study is to identify the cultivar differences in sensory attributes and organoleptic compositions of tomato fruits grown under salt stress and to elucidate their interaction among different cultivars using correlation network analysis. Salt stress was applied by adding 100 mM NaCl to the nutrient solution. Fruits were harvested at red-ripe stage and used for the evaluation of sensory attributes such as sweetness, sourness, umami, and tomato like, and organoleptic compositions such as sugar, organic acid, amino acid, and sodium ion contents. Almost all of the sensory attributes and organoleptic compositions of the fruit were significantly high in salt-stressed cultivars compared to non-stressed cultivars, and significant differences were also observed among cultivars. The correlation network analysis of the control fruit showed that compared to other traits, sugar is one of the key traits for improvement of tomato fruit quality based on high connectivity and betweenness centrality. In contrast, a high degree of positive connectivity was not observed between organoleptic compositions and sensory attributes in the salt-stressed fruit network. These results indicate that the relationship between sensory attributes and organoleptic compositions in fruits were different between the control and salt-stressed cultivars, suggesting that the salt-stressed fruit may have a different circuit of relationship compared to control. Furthermore, based on the increase ratio (salt stress/control) network results, we suggest that the increased sugar, organic acid, and amino acid contents may have contributed to the salt stress-induced enhancement of sensory attributes.  相似文献   

9.
我国是番茄生产大国,关于番茄的研究在我国蔬菜科学研究中占有十分重要的地位。以1999—2019 年“中文核心期刊”和“中国科学引文数据库”期刊上刊登的7 190 篇番茄研究文献为材料,使用Java 与python 编程语言实现对文献的计量分析,以期了解进入21 世纪后我国番茄科研的热点和变化趋势,为今后相关科研选题及管理提供参考。研究结果表明:近20 年来番茄研究的发文量,在前10 年间快速增长,随后的10 年间则保持高量稳定状态;文献聚类分析获得13 个研究主题,涵盖了遗传育种、栽培生理与栽培技术、植物保护、贮藏加工等研究领域;通过高频关键词分析发现,“基因”“生长发育”“产量”“品质”和“温室”等的相关研究热度持续不减,“黄化曲叶病毒病”“叶绿素”“幼苗”“樱桃番茄”和“土壤”等相关研究近年来热度明显升高,而“生理”“叶霉病”“贮藏保鲜”“青枯病”和“乙烯”等相关研究文献有所减少。最近10 年每年约有100 种中文核心期刊登番茄研究论文400 多篇。  相似文献   

10.
Urban tree inventories are useful tools to assess the environmental and socio-economic services provided by urban forests. These inventories enable the evaluation of the climate change risk to urban forests, and governments rely on such inventories for urban planning and management. Here, we assessed the future climate risk of Australia and the state of urban tree inventories across 116 local government areas (LGAs), representing 21 % of the country’s LGAs and encompassing 55 % of the national human population. We evaluated projected changes in temperature and precipitation by 2050 for each LGA and conducted a survey to obtain information on the extent and types of data available in existing urban tree inventories. Additionally, we compiled demographic, socio-economic, and geographical data for all LGAs to explore correlates with tree inventory status. Temperature increases in 2050 were predicted in all LGAs, with higher latitude and smaller LGAs identified to undergo greater increases in temperature compared to larger and lower latitude LGAs. Decreases in seasonal precipitation were predicted for 97 LGAs. Seventy-six (66 %) of surveyed LGAs had urban tree inventories, which most commonly included trees along streets and in parks. Sixty-one LGAs record information on tree mortality, while 31 LGAs dynamically update their inventories. The presence of an inventory and the area it covered were positively associated with human population density. More than 30 years ago, in 1988, John Gray wrote that “insufficient statistics were available in Australia to provide an accurate picture of the urban forest estate”. Our research shows there has not been a significant advance in the adoption and use of urban forest inventories over the past three decades. Long-term, dynamically updated inventories are crucial for urban forest management to inform planting choices to support sustainable and resilient cities.  相似文献   

11.
王燕  陈洁  赵华  姚蔚  韩旭  杜敏  张萍  韩李菲 《园艺学报》2018,45(12):2453-2454
对《园艺学报》来稿中试验处理缺少同期对照和试验结论与数据差异显著性结果不符的问题再次讨论,供作者参考。  相似文献   

12.
In July or August of 1988 and 1989 which was approximately 2 or 6 weeks, respectively, after fruit harvest, cultivar ‘Patterson’ apricot (Prunus armeniaca) trees were sprayed with a single spray of either 10, 50 or 100 p.p.m. gibberellic acid (gibberellin A3, GA). GA sprays of 100 p.p.m. applied in early July reduced flower number per centimeter of limb length in the year following treatment. Flower number per centimeter of limb circumference was reduced by sprays of 50 and 100 p.p.m. GA applied in July. Fruit set was not affected by GA sprays. The yield and fruit number of hand thinned trees was equivalent to that found on trees treated with 50 and 100 p.p.m. GA sprays in July. Individual fruit weight (size) was increased by GA sprays of 50 and 100 p.p.m. in July compared to hand thinned trees. Fruit maturity was advanced when yields were reduced by GA sprays. In July, GA sprays of 10 p.p.m. resulted in increased individual fruit weight without reduced total yields per tree compared to non-thinned control trees. Results showed that the use of GA sprays the year before flowering (July) decreased flower numbers, eliminating the need for chemical or hand fruit thinning of ‘Patterson’ apricot.  相似文献   

13.
In all major apple producing countries, applications of foliar calcium (Ca) products to increase fruit Ca content and reduce the incidence of bitter pit in apples are used. Calcium nitrate (Ca(NO3)2), Calcimax and Ca acetate were applied, commencing at three different developmental stages (early, mid and late) of fruit growth. Late Ca(NO3)2 (80 days after full bloom (dafb)) applications increased the Ca content of fruit at harvest more than early (six dafb) and mid (40 dafb) applications. There was a trend towards an increase in bitter pit from early to late applications of Ca(NO3)2 and Calcimax, confirming previous results obtained when applying only Ca(NO3)2. In spite of the very low incidences of bitter pit during these seasons (less than 7%), significant differences between treatments were found between Ca(NO3)2 Mid and other treatments in 2004/2005, as well as Ca(NO3)2 and Calcimax Early and other treatments in 2005/2006. Ca acetate applications did not show any trends in fruit Ca content or bitter pit incidence when applied during the three stages. Thus, products may differ in efficiency of Ca absorption and effectiveness in decreasing bitter pit in fruit when applied during different developmental stages.  相似文献   

14.
Rose plants that are flush harvested exhibit episodic growth patterns. During these crop cycles little biomass accumulation occurs immediately following harvest; and as new shoots emerge a period of rapid shoot growth and biomass accumulation occurs. The temporal changes in whole-plant nutrient and carbohydrate distribution during these crop cycles and the role of storage in new shoot growth are not well documented. The objective of this project was to quantify N, P, K, and total non-structural carbohydrates (TNC) distribution in roots, base stems, base leaves, and new shoots during crop cycles in response to light availability. Plants were grown in solution culture under high or low light (mean daily light integral 45.3 or 13.1 mol m−2 d−1, respectively) during 30–35 day crop cycles. Every five days destructive sampling was used to determine biomass and N, P, K, and TNC concentration of rose plant compartments. N and TNC accumulated in base plant compartments during the first ten days of the crop cycles. N, P, K, and TNC in base plant compartments declined during days 10–25 during a crop cycle concurrent with the rapid growth of flower shoots. N, P, and K storage in base plant parts represents 27, 22, and 24% of the potential N, P, and K required by flower shoots under high light; and 19, 21, and 22% of requirements under low light. TNC storage in base plant parts represents 4–10% of the final biomass of flower shoots. Mobilization of N, P, K, and TNC stored from base plant parts appears to be important during the stage of rapid flower shoot growth when absorption by roots or photosynthesis by shoots was insufficient to meet flower shoot demands. Plant carbohydrate status was improved under high light conditions; storage of N and TNC declined under low light.  相似文献   

15.
A two-year field study investigated the possible effects of grain sorghum (Sorghum bicolor [L.] Moench) and uncultivated areas on the abundance of generalist predators in commercially-managed cotton (Gossypium hirsutum L.) fields in Texas, USA. From 63 to 70 fields were sampled for pests and predators over nine consecutive weeks during early stages of cotton development. Additional data on agronomic practices and landscape composition at three spatial scales were also collected for each field. Stepwise regression analyses were used to determine the relationships of landscape, agronomic and prey variables to the abundance of generalist predators. Because the variables most closely linked to predator levels could vary over time, separate regressions were conducted for three time periods corresponding to stages of grain sorghum growth (half-bloom, hard-dough, maturity) in each year. Significant relationships between predator abundance and agricultural landscape composition appear in both years and in all three time periods, but the specific relationships of landscape variables to cotton predator levels differed between and within years. At maturity in 2001, predator levels rose as the amount of uncultivated land from 1.6 to 3.2 km distant and the perimeter shared with grain sorghum increased. During 2002, the area of grain sorghum (half-bloom) and uncultivated land (hard-dough) within 1.6 km of cotton fields were both positively related to predator numbers. Cotton planting dates and the abundance of cotton fleahoppers (Pseudatomoscelis seriatus [Reuter]) were also strongly linked to predator numbers during both years. Results suggest that the total amount of grain sorghum or uncultivated land in an area is more important than the presence of these habitats adjacent to cotton fields, and that landscape composition may sometimes be the most important factor in determining predator abundance.  相似文献   

16.
Urban green spaces (UGS) provide important contributions to people. Yet, UGS planning requires better understanding of by whom and where such contributions are being valued or missed. Based on a mixed-methods online survey and choice experiment with residents of Wellington in Aotearoa New Zealand, we analyse how much and why residents value UGS and their benefits when deciding where to live and how socio-economic and spatial factors might impact nature orientation and opportunity for satisfactory local UGS. We find that local UGS are an important residential choice criteria for the majority of respondents, especially in the context of Wellington’s intensification plans. However, we show that socio-economic and spatial factors significantly impact whether someone values and is satisfied with UGS in proximity to their place of residence. Our findings call for careful scoping of a city’s population and spatial structure when planning for equitable UGS provision. More holistic approaches to green space planning are needed to address contextualities and the complex interdependencies between nature orientation and opportunity and to plan for green space distributions that provide opportunities now and help shaping nature orientation for future generations.  相似文献   

17.
Our refuge design strategy involves a landscape approach formulated to complement existing management efforts and employ restoration in the heavily degraded Kankakee River watershed in northeastern Indiana and northwestern Illinois. The watershed historically contained an approximately 400,000 ha wetland (Grand Marsh), a diverse riverine system, oak savanna, and prairie. Today only fragments of these habitats remain. The U.S. Fish and Wildlife Service developed a preliminary project proposal (PPP) during the summer of 1996 to protect and restore habitat within the watershed by establishing the Grand Kankakee Marsh National Wildlife Refuge. The Indiana and Illinois Gap Analysis projects provided the resources to move beyond the expert workshop approach to a data-driven method for initial reserve design. Using visual analysis of various Gap Analysis data layers, we established Focus Areas that formed the basis for the Environmental Assessment and the Economic Impact Study required under the National Environmental Policy Act (NEPA). We have initiated Phase II of the reserve design analysis using preliminary results of the Indiana Gap Analysis project and C-Plan software in conjunction with the New South Wales National Parks and Wildlife Service.  相似文献   

18.
Despite problems of low fruit set, small fruit size and alternate bearing, the Hass cultivar dominates commercial avocado production worldwide. To increase yield and fruit size, gibberellic acid (GA3) (25 mg L−1) was applied at different stages of ‘Hass’ avocado tree phenology: (i) mid–late April (flower abscission), end of June–beginning of July (fruit abscission and beginning of the exponential phase of fruit growth), and mid-January (beginning of pre-harvest fruit drop); (ii) end of June–beginning of July; and (iii) mid-September (near the end of the major fruit abscission period; period of exponential fruit growth). In both years of the research, applications of GA3 in April and June–July were within the periods of intense flower and fruit abscission, respectively; fruit abscission was low in September and January. Maximum air temperature was not related to flower or fruit abscission. In the on-crop year (391 fruit per untreated control tree), a single application of GA3 at the end of June–beginning of July significantly increased total yield (kilograms only) and yield of commercially valuable fruit (178–325 g/fruit) (as kilograms and number per tree) compared with the control (P < 0.0001). GA3 applied in September increased total yield (kilograms only) and yield of commercially valuable fruit (kilograms and number per tree) to values intermediate to and not significantly different from all other treatments, except trees receiving multiple applications of GA3. This treatment reduced total yield and yield of commercially valuable fruit (kilograms and number per tree) relative to all treatments (P ≤ 0.0002). In contrast, during the off-crop year (32 fruit per control tree), no GA3 treatment had a significant effect on yield or fruit size compared with the control and all other GA3 treatments. For ‘Hass’ avocado, there was no negative effect from applying GA3 at the end of June–beginning of July in both the off- and on-crop years; 2-year cumulative total yield and yield of commercially valuable fruit were increased by 27 kg (128 fruit) and 22 kg (101 fruit) per tree, respectively, above the yield of untreated control trees (P < 0.0001).  相似文献   

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