Revising Articles Written on the Land—Commencement Speech at 2022 Graduation Ceremony of the College of Architecture and Landscape,Peking University

This article is the author’s commencement speech at 2022 Graduation Ceremony of the College of Architecture and Landscape, Peking University. Away from the cities, the author observed, experienced, and recorded the changes in vernacular landscapes: pesticide abuse and cutoff and channelized rivers have resulted in soil hardened, loaches, eels, frogs, and other creatures disappeared, and rivers and water sources seriously polluted; while demolishing the vernacular cultural heritage of the ancient town, the reconstructed one is built with a large number of ornamental, ancient-looking structures, and stereotyped symbols, mirroring the shallow understanding of aesthetic, historical, and cultural identities. Metaphorically, the author is so ashamed of these „articles written on the land” and encourages the graduates to revise them in the future with their knowledge of ecology and aesthetics.     

基于生物多样性保育的山区乡村生态振兴模式探索 ——以武陵山区桥头镇为例

山区高环境空间异质性对于生物多样 性维持具有重要支撑作用,生物多样性是乡村 绿色发展的重要基础资源。生态振兴是山区乡 村振兴的重要发展方向,其中生物多样性保育与 可持续利用已成为乡村生态振兴的重要途径。西 南武陵山区是中国生物多样性热点区域,丰富而 独特的生物多样性为武陵山区乡村生态振兴奠 定了良好基础。本文以地处武陵山区的重庆市 石柱县桥头镇为例,基于其“林—草—湿”一体 化的优良生态本底和丰富独特的山地生物多样 性资源,针对山区立体环境特征、生态资源禀赋 和生物多样性现状,在探讨其山地生物多样性 特征的基础上,提出了基于生物多样性保育的乡村生态振兴目标、策略及模式,为山地区域从多空间维度、多时空尺度、多产业层次实现乡村生态 振兴提供借鉴。     

The ecological peculiarities of the testate amoebae population in the Middle Ob flood plain

The biodiversity and distribution of testate amoebae in the Middle Ob flood plain soils have been studied. The biodiversity of Testacea in the soils consists of 83 species and varieties from 12 families. The population of Testacea in flood plain habitats is rich in water forms, especially in the flood plain part of the catena, because of annual floods. The study showed that the density of Testacea in the forest plots is approximately 10 times higher than in the meadow ones. The species diversity of Testacea in the meadows of the flood plain includes 40 species and varieties. It was found that there is an enrichment of the fauna of Testacea in the flood plain meadows with water forms and a decrease in the population of Testacea in the soil according to the depth. The decrease in the diversity and number down the soil profile is related to the decrease in the amount of the oxygen available and general induration of soil. On the whole, the population composition of Testacea in the soils of the pine forest consists of typical representatives of humus substrates with low values of pH, small stock of humus and mineral nutrition. The soils of mature pine forests are rich in Testacea; they have a similar complex of morphological types, mainly because of the moss cover and forest litter thickness.     

城市生物多样性恢复途径与实例研究

城市生物多样性是城市生存与发展的基础,是实现城市生态系统可持续性的保证。本文以相关生态学理论为指导,针对广州市海珠生态城的生态恢复实际,并结合海珠生态城"以万亩果林湿地为核心,打造具有岭南水乡魅力的花城、水城、绿城特色生态城市样板区"的总体定位,提出了该区域的生物多样性恢复目标和规划思路,并重点围绕湿地生境分区、栖息地修复、水环境改善、恢复物种筛选、区域生物多样性构建等方面进行了探讨,建立了海珠生态城湿地生物多样性恢复规划策略。     

Development of a regional food composition table for West Africa

Knowledge of the nutrient content of foods is fundamental for virtually all nutrition-related projects, programmes and policies. Low quality compositional data may lead to inappropriate policies and funds spent unnecessarily. Existing food composition tables (FCT) for most West African countries date back to 1960 and 1970 and contain in general few foods and components without documentation. As a result of the recommendations by the Economic Community of West African States (ECOWAS) Nutrition forum and other high level meetings, FAO/INFOODS, WAHO/ECOWAS and Bioversity International developed the West African FCT. It contains 472 foods and 28 components. Emphasis was given to include data on food biodiversity by incorporating cultivars/varieties and underutilized foods. The West African FCT enables users to address diet-related health problems, strengthen local development, enhance trade and promote biodiversity. In addition it contributes to poverty alleviation in both rural and urban areas. The FCT needs to be updated regularly and it is the most recent example of INFOODS for regional food composition activities.     

Assessing the Floristic Diversity of Hedge Networks: A landscape perspective

The type of land cover adjacent to hedges has been shown to influence the species composition of the ground flora. An assessment of the contribution of hedge networks to the biodiversity of landscapes therefore requires information on the relative lengths of hedge associated with different land covers. In the River Tyne catchment, Northern England, the association between hedges and land cover types differed between four landscapes. Overall, the greatest length of hedge was adjacent to arable crops, improved grasslands and roads. Hedges next to improved grassland and roads were the most species-rich, while those adjacent to arable crops were the least species-rich. Species which were common adjacent to arable crops were also common adjacent to other land covers. Hedges adjacent to improved grassland, roads and semi-natural broadleaved woodland supported species which were not common elsewhere in the hedge network. It was also found that hedges with different land cover on each side supported different floras on each side. When planning landscape-scale surveys of hedge biodiversity, it is important to survey both sides of hedges, and sampling should be stratified to include hedges adjacent to the different types of land cover present.     

FUNCTIONAL CONNECTIVITY ANALYSES AND CONSTRUCTION STRATEGIES OF THE STRUCTURE OF GREEN SPACE NETWORK IN HAIDIAN DISTRICT OF BEIJING

Urban green space structure and pattern have been one of the highlights in Landscape Architecture studies, accompanying with urgent demands of promoting ecological spatial structures in urban construction. Focusing on functional connectivity and construction strategies of the structure of green space network in Haidian District of Beijing, this research builds resistance surface and identifies linkages through habitat quality evaluation of the InVEST Model and the simulation with the Least-Cost Model, while adopting functional connectivity index (NL, NC, IIC, PC, and dIIL) to indicate the structural characteristics of green space network at varied distance thresholds. Results reveal that, on the whole, the distance threshold of 2,200 meters is most appropriate for the structure of the existing green space network of Haidian District, when 10 components and 353 linkages are identified and six important nodes and three important linkages that require a protection priority are further determined. Findings also disclose that the forest network of target tree species and that of water network of target water bird species are highly fragmented. Forest network serves in forms of dominant patch structure, local network structure, and fragmented cluster structure in the western mountainous area, the northern plain area, and the southeastern urban area, respectively. Moreover, the research proves that by introducing ten important linkages, the connectivity of forest network can be improved by 1.7 times, completing the overall structure in multiple directions and helping form a stable and resilient structure of the network. Finally, the research puts forward strategies for urban green space construction, including identifying construction objectives and target species, identifying and protecting important nodes and important linkages, and introducing possible important linkages and improving the structure of green space network, to help efficiently improve urban ecological quality.     

Identification of potential areas for biomass production in China: Discussion of a recent approach and future challenges

A standard methodology is needed to recognize potentially suitable areas for sustainable bioenergy crop production. This facilitates better identification of promising crops and cropping systems, logistical and economic studies, and work needed to meet regulatory criteria. A possible approach is built upon three layers of internationally available spatial data: (1) degrading and abandoned areas, (2) potentially suitable land cover classes, (3) exclusion zones such as nature reserves and areas of high biodiversity. For China, areas identified as potentially suitable range from 1.2 to 6.0% of the national territory, depending on different levels of statistical confidence in degrading area status and allowable limits of terrestrial carbon. Verification on the ground showed that about 60% of points tested conformed to the remote suitability assessment in the scenario, which represents the results for the combination of all degrading areas and a terrestrial carbon stock limit of 200 t ha⁻¹. A top-down approach is useful in framing potentially suitable locations, but a complementary bottom-up analysis is still required to ultimately identify areas for sustainable bio-fuel production.     

Chemical and biological variability of hot pepper fruits (Capsicum annuum var. acuminatum L.) in relation to maturity stage

The aim of the present work was to evaluate the chemical composition and the radical-scavenging and antioxidant activities of hot pepper fruits (Capsicum annuum L. var. acuminatum) at three maturity stages (small green, green and red). GC–MS analysis of n-hexane and chloroform fractions showed a different composition between the three stages of ripening. The first stage of maturation (small green) showed the highest radical-scavenging activity (IC₅₀ of 129 μg/ml). Using the bovine brain peroxidation assay, the methanolic extract of green pepper showed significant antioxidant activity (IC₅₀ of 522 μg/ml). Addition of methanolic extract of red and green pepper inhibited oxidation of linoleic acid. Methanolic extract of red pepper showed greater antioxidative potency than the others (IC₅₀ of 3 μg/ml). The different composition of lipophilic compounds and the various amount of phenolics, showed in the three stage of ripening of C. annuum var. acuminatum fruits, modifies the antioxidant activity.