轻型屋顶绿化植物栽培基质配方筛选研究

以垂盆草(Sedum sarmentosum)、凹叶景天(Sedum emarginatum)、高景天(Sedum kamtschaticum var.ellacombeanum)等3种景天科植物为供试植物,以堆肥、煤渣、陶粒、河沙等为原料,进行了不同配比的轻型屋顶绿化栽培基质配方试验;并采用聚类分析及投影寻踪综合评价方法,对栽培基质配方理化特性及栽培效果进行了比较,以期筛选出不同植物适宜的栽培基质配方.结果表明:采用投影寻踪综合评价方法可对植物多指标参数进行有效降维处理,是栽培基质筛选研究的良好方法;筛选出的栽培基质配方适宜我国轻型屋顶绿化系统特征,具有较好的推广前景.     

墨脱地区野生白果草莓的性状鉴定及其果实品质分析

采用植物学分析方法对墨脱地区所采集的野生白果草莓进行植物学性状鉴定,并运用对比分析方法对果实质量进行了分析和定量评价。结果表明:所采集的野生白果草莓为西藏草莓(F.nubicola Lindl),与栽培上常用的大果草莓"甜查理"相比,西藏草莓平均单果重、纵径、横径和果形指数等表型指标,以及平均可溶性固形物含量、可溶性糖含量、可溶性酸含量、糖酸比和维生素C含量等果实品质指标均极显著或显著低于对照,而且平均总糖含量也明显低于对照;综合各表型性状和果实品质性状建立投影寻踪(PP)模型进行量化分析,墨脱西藏草莓果实品质函数投影值为0.8751,远低于对照的3.2907。由此说明,在品质上墨脱西藏草莓果实品质与生产上常见的大果草莓品种相距甚远,今后可作为白果草莓育种材料和草莓抗性育种材料。     

不同沙棘品种的抗旱性比较

为明确不同沙棘品种抗旱性,选取15个沙棘品种为试材,测定其叶片自然饱和亏、临界饱和亏、自由水含量、束缚水含量、自束比等生理指标,运用投影寻踪法,对15个品种沙棘的抗旱性进行了综合评价。结果表明:各品种抗旱性强弱顺序为"太阳""阜欧""杂优59号""杂优12号""杂优2号""杂优54号""中俄杂优""阜杂1号""杂优1号""杂优5号""杂优10号""杂优31号""杂优28号""蛮汉山""红霞"。     

林芝地区西藏草莓的果实质量评价

以西藏草莓为试材,以大果草莓"甜查理"为对照(简称栽培草莓),采用对比分析法研究了西藏草莓表型及品质性状,以期为今后西藏草莓的资源利用工作奠定基础。结果表明:西藏草莓平均单果质量、平均纵径和平均横径均低于对照,品种间差异极显著(P<0.01,n=30),但果形指数品种间差异不显著;可溶性固形物含量品种间差异显著(P<0.05,n=5),可溶性酸含量及维生素C含量品种间差异极显著(P<0.01,n=5),可溶性糖含量品种间差异不显著(P>0.05,n=5);综合表型性状和果实品质性状建立投影寻踪模型进行量化分析发现,西藏草莓果实品质函数投影值远低于对照。与对照相比,西藏草莓果实偏酸,风味特殊,但果实综合质量较差,今后可作为风味草莓育种材料来开发利用。     

温光条件对冬茬黄瓜生长发育及产量形成的影响

对冬茬黄瓜生育期间的温度、光照变化以及黄瓜生长发育动态和产量形成规律的观测结果表明：受低温弱光影响，冬茬黄瓜植株节间长，叶片分布稀疏，叶面积受人为落蔓作用，呈波动式变化；结果期间叶面积指数为１～２．４０。１２月中旬至元月中旬黄反果实长成时间平均２７．９天，日增长量仅４．８１ｇ，至４月上旬果实生长量为深冬的３位。投影寻踪回归（ＰＰＲ）分析表明，日照时数、日总辐射量和有效积温对冬茬黄瓜产量影响最大，地温大于气温对产量的影响     

瓜菜种植承租商评价指标体系构建及寻优研究

土地流转过程中,综合实力优越的瓜菜种植承租商可使得流转土地的产出与投入价值比得到较大提升。采用一种改进的CS-PP算法,将布谷鸟搜索算法优异的非线性寻优能力与投影寻踪方法良好的高维数据处理能力结合,通过局部随机搜索技术处理土地流转过程中对瓜菜种植承租商的寻优。结果表明,改进CS-PP算法的Q值大,目标解的寻优能力较强,优于RAGA-PP算法与PSO-PP算法,可应用于土地流转过程中的瓜菜种植承租商寻优尝试。在不改变家庭承包经营制度的基础上,采用土地流转方式将土地交给合适的瓜菜种植承租商运营,可实现第一产业由传统向现代转型,有利于公有制与市场的深度铆合,更深层次地促进集体经济的发展。     

观光果园景观质量评价体系的研究

观光果园是以绿色果品生产和生态旅游相结合的新兴产业.景观质量评价对观光果园建设前的方案评估和建成后的优化方案都具有重要的理论和实践指导意义.该研究以观光果园景观质量为总目标,运用层次分析法,从景观、景观元素、景观元素特征的隶属层次,建立了观光果园景观质量的评价体系,得出了各类因子在观光果园景观质量中所占的权重,反映了各因子之间的主次关系.结果表明:观光果园主要以自然景观为主,兼顾人文景观和工程景观,各景观的相对权重为72.6%,17.2%,10.2%;在景观元素层上,应重点考虑以果树为特色的景观,其次要开展以果树资源为独特性的体验活动,再次是结合水体、园林植物、园林建筑、民风民俗、道路、灌溉设施、园墙等艺术处理,科学布局,构建独具风格的观光果园.在此基础上,运用模糊数学,进行综合评判,指导观光果园的设计和优化.     

板栗施硼时应注意的问题

板栗缺硼时会出现大量的空蓬和独粒现象,对板栗的质量和产量造成很大的影响.板栗空苞已成为板栗生产上的主要问题,必须对栗树施硼.在给板栗树施硼时要注意以下几个问题. 1 施硼量不能过多 按树冠投影大小计算,每平方米施硼砂10～20 g为宜.施在树冠投影外围吸收根集中分布的区域.如果每平方米树冠投影施硼超过40g,即发生药害,表现出硼中毒的症状(叶边缘及叶脉间呈现褐色,叶片变脆,叶脉弯曲,叶片抱拢);如果每平方米超过60g,则全树叶片边缘呈红褐色,并向中心发展,叶片逐渐枯萎.顶端幼叶更为敏感.     

生物图玻璃板起稿绘图法

生物图是为生物科学研究和生产服务的科学图。进一步提高绘图水平和工作效率,是绘图工作者的重要任务。而改进绘图技法和器具,是提高绘图水平和效率的重要环节。通常,绘生物图先对标本进行观察了解和构图安排,其次再画出轮廓,按标本的明暗关系,深入细致的描绘。绘图中,初学者普遍采用九宫格实物描绘器、灯光投影法、玻璃折光起稿法和幻灯反光投影法起稿,经修改后描绘成图。     

小陇山高桥林场落叶松叶蜂生态学特性初步研究

在掌握小陇山林区落叶松叶蜂生物学特性的前提下,为进一步了解其生态学特性,在温湿度相差不大的同一地区,采用野外调查,主要从落叶松叶蜂发生与寄主、坡向、坡位、灌草层投影盖度、树势、天敌、人为干扰7个方面的影响进行了研究。结果表明:落叶松叶蜂寄主为日本落叶松(Larix kaempferi(Lamb.)Carr.)和华北落叶松(Larix principis-rupprechtii Mayr.)[1];虫口密度与坡向关系顺序是:阳坡半阴半阳坡阴坡;种群密度是随海拔的升高呈上升趋势;随着灌草层总盖度的增大危害越轻,弱树受害重于强树;幼虫期天敌有蜘蛛、蚂蚁、草蛉、鸟等;人为干扰方面采取间伐措施可明显地降低虫口密度。     

有机基质对番茄穴盘苗生长及根系形态的影响

以腐熟菇渣与等量牛粪混配作为有机基质,常规草炭基质为对照,研究了有机基质对番茄穴盘苗生长及根系形态的影响.试验结果表明,有机基质培育的番茄幼苗茎秆粗壮,植株鲜质量及干质量均显著高于对照处理;与对照相比,叶片叶绿素a含量、根冠比及壮苗指数均显著增大.另外,有机基质还显著促进了番茄幼苗根系的伸长,根系表面积、根系投影面积以及根系体积显著增大,根尖数目显著增加.随着根系直径范围的增加,有机基质培育的番茄幼苗根系总长度及总体积均呈现出逐渐减小的趋势;总表面积及总投影面积均呈现出先增大后减小的趋势,在0.2~0.4 mm直径范围内达到峰值.综合认为,本试验条件下的有机基质配方适宜于番茄幼苗的生长,可培育出性状优良的番茄幼苗.     

Diagnostic tools to evaluate a spatial land change projection along a gradient of an explanatory variable

This paper proposes a method to quantify the goodness-of-fit of a land change projection along a gradient of an explanatory variable, by classifying pixels as one of four types: null successes, false alarms, hits, and misses. The method shows: (1) how the correctness and error of a land change projection are distributed along the gradient of an explanatory variable, (2) how the gradient of the explanatory variable relates to the stationarity of the land transition processes, and (3) how to use the insights from the previous two points to search for additional explanatory variables. The paper illustrates the method through a case study that applies the model Geomod in Central Massachusetts, USA. Results reveal that the model predicts more than the observed amount of change on flat slopes and less than the observed amount of change on steep slopes. One reason for these types of errors is that the land change process during the calibration interval is different than the process during the prediction interval with respect to slope. The method allows modelers to use the validation step as a diagnostic tool to search for potentially influential missing variables and to gain insight into land transition processes. The technique is designed to be applicable to a variety of types of land change models.     

Population dynamics and habitat connectivity affecting the spatial spread of populations – a simulation study

In this paper we show how the spatialconfiguration of habitat quality affects the spatial spread of apopulation in a heterogeneous environment. Our main result is thatfor species with limited dispersal ability and a landscape withisolated habitats, stepping stone patches of habitat greatlyincrease the ability of species to disperse. Our results showthat increasing reproductive rate first enables and thenaccelerates spatial spread, whereas increasing the connectivity has aremarkable effect only in case of low reproductive rates. Theimportance of landscape structure varied according to thedemographic characteristics of the population. To show this wepresent a spatially explicit habitat model taking into accountpopulation dynamics and habitat connectivity. The population dynamicsare based on a matrix projection model and are calculated on eachcell of a regular lattice. The parameters of the Leslie matrix dependon habitat suitability as well as density. Dispersal between adjacentcells takes place either unrestricted or with higher probability inthe direction of a higher habitat quality (restricted dispersal).Connectivity is maintained by corridors and stepping stones ofoptimal habitat quality in our fragmented model landscape containinga mosaic of different habitat suitabilities. The cellular automatonmodel serves as a basis for investigating different combinations ofparameter values and spatial arrangements of cells with high and lowquality.This revised version was published online in May 2005 with corrections to the Cover Date.     

Predicting canopy and trunk cross-sectional area of silver linden (Tilia tomentosa) in confined planting cutouts

Urbanized land is characterized by the dominance of paved surfaces. Increasing tree canopy in urbanized areas has been identified as an effective way to reduce stormwater runoff, sequester carbon, improve air and water quality, and otherwise mitigate the environmental impacts and increase the livability of cities. However, attaining sufficient tree canopy in urban areas remains an elusive goal. Site design characteristics such as cutout size may limit urban tree growth and complicate efforts to predict future canopy, especially in highly paved systems such as parking lots. We studied 25 silver lindens (Tilia tomentosa Moench) grown for 14 years at one site, in pavement cutouts of various sizes. Regression analysis, even on these limited data, indicated a strong relationship between tree size and canopy projection area and unpaved soil surface area, but not soil depth. Cutout size explained 70% of the variability in tree canopy projection area and 77% of the variability in trunk cross-sectional area. The addition of other variables, such as soil bulk density, did not improve the model. Trees growing in parking lot cutouts <5.3 m² attained only limited size, regardless of the level of soil compaction. In larger cutouts, however, increases in soil bulk density from 1.1 to 1.5 Mg/m³ were associated with a 70% reduction in trunk cross-sectional area. In order to create urban sites with a sustainable tree canopy, site design must provide large areas of uncompacted soil for trees and protect this soil from compaction during use. Urban tree growth models that incorporate cutout characteristics are needed to predict future canopy area with confidence.     

新疆野苹果居群年龄结构及郁闭度研究

对新疆巩留与新源2地的新疆野苹果居群年龄结构及郁闭度进行测定和分析,旨在为新疆野苹果资源的保护保存提供依据。结果表明,在随机选取的200个单株中,巩留居群Ⅰ级幼树为0,而且Ⅱ级小树数量也极少,仅2株,只占1%,年龄级构成有下降性特征,存活曲线呈断点凸型,故年龄结构应属老衰类型,郁闭度为0.47;新源居群有Ⅰ级幼树,10株占5%,Ⅱ级小树达26株占13%,年龄级构成有稳定中略有上升的特征,存活曲线呈弧形凸型,故年龄结构应属稳定类型,郁闭度为0.80。上述结果显示,巩留新疆野苹果居群破坏严重,亟待加强保护,而新源新疆野苹果居群保存较完好。     

Landscape-level interactions between topoedaphic features and nitrogen limitation in tallgrass prairie

Transects across watersheds with varying fire histories and remotely-sensed data were used to study vegetation-resource interactions in a tallgrass prairie in Kansas. Paired plots (fertilized, control) were established along these transects and sampled for grass and forb biomass during the 1989 and 1990 growing seasons. Fertilization resulted in significant production responses in grass and total biomass on the west slopes of the annually burned (ID) and infrequently burned (N4) watersheds for both years (p = 0.05). In 1989, fertilization also produced a significant increase in grass biomass on the west slope of the unburned transect (p = 0.05), however, total production was not significantly increased. East slopes were insensitive to nitrogen additions. Differences in production response along these transects were assessed by testing the interaction between fertilization response and slope position. Significant interactions occurred on both 1D and N4, but only in 1990.Production data for both years were also compared to Normalized Difference Vegetation Index (NDVI) values derived from thematic mapper (TM) images for 1989 and 1990. When differences among transects or watersheds were statistically different, a positive relationship between NDVI and biomass was observed. NDVI values accurately reflected the spatial patterns of production along these transects for both years although not necessarily the magnitude.     

Carbon storage in a peri-urban neotropical forest: Assessing its potential and patterns of change over half a century

Forest ecosystems are associated with environmental regulation services, such as carbon storage, which is an outstanding service. Carbon fluxes in cities are difficult to estimate due to the scale at which they are addressed, particularly at the local level. In this work, we were interested in determining the carbon stored in the aboveground biomass of the tropical montane cloud forest tree species located on the western periphery of the city of Xalapa, Veracruz, Mexico. With these data, we interpolated the storage and sequestration over five decades through image satellites and aerial photography of this unique forest. Additionally, to assess this potential as a basis for a biodiversity contribution to city resilience, we conducted phytosociological sampling. Native species such as Quercus xalapensis, Liquidambar styraciflua var. mexicana and Q. lancifolia showed the most significant values of 72.92, 58.79, and 49.14 Mg ha⁻¹, respectively, of carbon. We used phytosociological sampling to better understand structural and functional features of urban forest biodiversity that can contribute to management practices for adaptation to climate change. In addition, the native species currently studied offer an opportunity for the city to implement better-targeted reforestation and ecological restoration programs for integrated landscaping in urban planning. Our results suggest that between 1966 and 2022, there was a forest recovery of 52.4 ha and an increase in urban areas of 63.4 ha, which is equivalent to an increase from 7,700.86 Mg ha⁻¹ in 1966 to 12,620.00 Mg ha⁻¹ in 2022. In this context, it is possible to both recover the vegetation cover and expand the city, thus avoiding part of the loss of ecosystem services that urbanization usually implies. This should be promoted among decision-makers and citizens in urban planning. Recovery processes can take place successfully in some cases even as urban areas expand. This possibility is relevant due to the many contributions that vegetation provides to citizens, including carbon storage. The opportunity to study five decades allows us to know the history, monitor the processes and make a projection to conserve the vegetation and improve management.     

Activating effect of astragalus saponin on mouse peritoneal macrophages in vitro

AIM: To investigate the immunomodulatory effect of astragalus saponin (AS) on macrophages and explore the mechanism of its immunomodulation. METHODS: By adding different concentrations of AS into cultured mouse peritoneal macrophages in vitro, the influence of AS on the synthesis of nitro oxide (NO) was detected by NO kit (enzymatic method). MTT assay was used to determine the cytotoxicity of macrophages induced by AS. The morphological changes of macrophages were observed under transmission electron microscope. LSCM and specificity fluorescent probe Fluo-3/AM were applied to observe the change of Ca2+ in macrophages induced by AS. RESULTS: AS significantly increased NO synthesis, enhanced the effects of mouse peritoneal macrophages on killing carcinoma cells. Cell surface projection exhibited multiplication, becoming thickening and growth longer via transmission electron microscope. Increase in intracellular Ca2+ in macrophages was also observed. CONCLUSION: AS enhances the immune function of macrophages by increasing NO synthesis and enhancing cytotoxicity. The increased intracellular Ca2+ may be the mechanism of immunomodulatory effect of AS.     

Beliefs about urban fringe forests among urban residents in Sweden

The aim of this study was to examine predictors of beliefs about urban fringe forests among urban residents in Sweden (n = 586). Based on a cognitive hierarchical model, the study investigated how socio-demographic variables, as well as different values and beliefs, were related to the more specific beliefs urban residents have about urban fringe forests. Results demonstrated that the urban fringe forest was perceived to be essential for personal wellbeing, but preservation and accessibility to the forest were also important. Certain differences between socio-demographic groups were identified; for example, the importance of urban fringe forests for personal wellbeing was emphasized more by women, older people and those with a university degree. However, the importance of socio-demographic variables was modest compared with the influence of people's values and beliefs. More specifically, results showed that urban residents’ basic values and ecological worldview, as well as forest values and beliefs (i.e., concerning forest qualities and forest requirements), were important in explaining their beliefs about urban fringe forests. Overall, the study revealed that urban residents are characterized by a heterogeneous set of beliefs concerning urban fringe forests. Recognizing these multiple beliefs in urban fringe forest development processes may help mitigate future conflicts between forest visitors, urban planners, forest owners and forest managers, thus enhancing our way toward good urban living environments.