杭州市自然保护地现状与空间分布格局特征分析

为揭示杭州市自然保护地的空间分布特征，探讨本区域自然保护地体系整合方向，以杭州市的自然保护地为研究对象，运用Arc GIS技术，分析自然保护地空间分布特征与交叉重叠情况。结果表明，杭州市共有87处自然保护地，累计面积3 447.86 km²(含重叠面积)，占全市国土面积的20.46%，其中富阳区、桐庐县、建德市和淳安县的50处自然保护地占杭州市自然保护地总面积的80.52%；各类自然保护地交叉重叠面积为858.99 km²，且主要集中于风景名胜区与森林公园之间，其重叠面积达831.87 km²；自然保护地内矛盾用地总面积为612.65 km²，其中人工商品林和永久基本农田最为突出，分别占矛盾用地总面积的40.90%和18.61%。     

云南省发展澳洲坚果生态环境条件的模糊灰色区划

本文应用灰色系统理论中的灰色关联度分析方法［１］，选取与澳洲坚果生长发育关系密切的５个农业气象因子作为区划指标，通过对澳洲坚果最适生长的气象指标与云南热带和亚热带各地区气象条件的关联分析，初步得到云南热区各地与澳洲坚果最适气象指标之关联度；据此进行云南澳洲坚果生态适宜区区划，并对各分区进行评述，以期为云南省澳洲坚果宜植地区划与布局提供科学依据。     

云南省澳洲坚果产业发展现状及对策

指出了云南省澳洲坚果产业已成为云南新兴高原特色生物产业,且种植面积位居全国第一。但目前云南省澳洲坚果总产量较低,经济效益不明显,产业大而不强。基于此,分析了云南省坚果生产模式及现状,针对云南省澳洲坚果发展现状的问题,提出了相应的对策及产业发展建议,以将云南的澳洲坚果资源优势发挥到最大化,助力云南省"大力发展高原特色现代农业,打造绿色食品牌"的战略部署,为云南省澳洲坚果产业的可持续健康发展提供参考。     

气候变化背景下云南沙棘在中国的潜在地理分布

基于云南沙棘在中国的78个种群分布点位数据与22个地理环境变量，利用MaxEnt模型模拟了云南沙棘在当前气候与未来(2050S、2070S)3种不同气候情景(RCP2.6、RCP4.5和RCP8.5)的潜在地理分布，探讨影响云南沙棘分布的主导环境变量，揭示未来气候变化下云南沙棘的变化趋势。结果表明：(1)影响云南沙棘生长的主要环境变量为热量(温度季节性变动系数、等温性、最冷季平均温度)、地形(海拔、坡度)和水文(年降水量),其中海拔、年降水量及温度季节性变动系数对其影响极其显著，累计贡献率为60%;(2)当前气候情景下，云南沙棘的高适宜生境与适宜生境面积分别为5.88×10⁴km²和23.97×10⁴km²,分别占中国国土面积的0.61%与2.49%,适宜种植生境集中分布在我国横断山脉地区；(3)2041—2060年间3种不同气候情景下云南沙棘适宜生境和高适宜生境面积为增长趋势，在2061—2080年间RCP8.5情景下云南沙棘的高适宜生境为减小趋势，适宜生境呈现增加趋势。云南沙棘适宜生境有向西南方...     

基于MaxEnt生态软件划分澳洲坚果的潜在地理适生区

[目的]对澳洲坚果在中国的潜在分布区进行预测,并对其适生区进行分析和划分。[方法]通过收集澳洲坚果的地理信息数据,利用最大熵模型(MaxEnt)与地理信息系统(ArcGIS),综合相关19项气候因子,预测划定澳洲坚果在世界以及我国的潜在地理分布区。[结果]该物种生长区域狭窄,对环境要求苛刻。世界范围内,澳洲坚果的较适宜生长区在澳洲东部、南美洲东南部和马达加斯加岛东部以及亚洲地区23°26'~30°N,73°~122°E范围内。在我国,澳洲坚果适宜分布区主要集中在西藏、台湾、广西、广东和云南等地,其高适宜区面积依次为西藏(15 359km~2),台湾(14 054 km~2),广西(7 372 km~2),广东(6 147 km~2)和云南(3 776 km~2)。刀切法(Jackknife)分析显示,澳洲坚果分布主要受到极端最高温、年均气温变化范围、最干月降雨量、温度季节性变化和等温性等气象因子的影响。[结论]本研究用MaxEnt模拟澳洲坚果的潜在地理分布有一定的准确性,划分出了澳洲坚果基本的地理分布格局和潜在分布区域,并阐明了主导其地理分布的生物气候因子,为澳洲坚果尤其是在我国的引种和推广应用提供了参考。     

云南辣木种植生态适宜性区划

利用气候环境数据结合辣木8个生态适宜性气候指标,将云南划分出辣木种植的高适生区、低适生区和不适生区,并制作云南辣木适生区专题图。结果表明,云南辣木适生区分布于北纬25°以南海拔1 600 m以下地区和金沙江海拔1 600 m以下峡谷。辣木在云南普洱市、西双版纳州、红河州、临沧市、德宏州等11个州(市)有高适生区面积37 110 km2,占云南省国土面积的9.5%;在全省15州(市)有低适生区面积69 036 km2,占云南省国土面积的16.3%。云南辣木适生区多为干热河谷、山区丘陵,生态环境恶劣,经济落后地区。研究结果将为云南辣木科学种植提供参考。     

基于最大熵模型的气候变化情景下澳洲坚果潜在适宜生境研究

为了研究气候变化情景下澳洲坚果在云南省的潜在适宜生境,采用当前和未来2050年RCP45气候变化情景下的19个生物气候因子及最大熵模型MaxEnt进行澳洲坚果生境模型构建,并进行适宜生境等级划分及空间变化特点分析。结果表明,2050年RCP45气候变化情景下3个等级的适宜生境大体上仍然保持与当前相似的空间分布格局,即高度适宜生境主要分布在云南西南部和南部,中、低度适宜生境分布在高度适宜生境区以北及以东区域。未来气候变化引起高度和中度适宜生境面积小幅度缩减(5.6%和2.4%),低度适宜生境面积增加22.5%。气候变化同时引起高度适宜生境景观格局破碎化。未来气候变化引起的澳洲坚果在云南高、中度适宜种植区总面积略有缩减,虽幅度不大,但空间分布上发生位移,且呈现破碎化趋势,产业规划时应考虑产业生命周期内气候变化造成对适宜生境迁移的影响。     

澳洲坚果在云南热区的开发前景

对澳洲坚果的生物学特性及生态适应性分析结果,云南北热带、南亚热带湿润、半湿润地区属于该树种的适宜和最适宜种植区。其种植原则以优良无性系及多品种混交为主;栽培技术包括种植形式与密度;叶片营养诊断指导施肥及病虫害防治。云南热区引种试种的成功及云南热区的自然资源、土地资源优势为澳洲坚果的开发提供了必要条件,开发前景看好。     

基于GIS的武夷山国家公园生态敏感性分析

于2021年6月,筛选10个评价因子,运用ArcGIS 10.2的空间叠加分析与重分类工具对福建武夷山国家公园的环境资源进行生态敏感性综合评价。结果显示,武夷山国家公园的综合生态敏感性较低,可划分为5个敏感等级区域：极敏感区123.65 km²、高敏感区271.63 km²、中敏感区284.75 km²、低敏感区194.1 km²、不敏感区67.02 km²,所占比例分别为13.14%、28.86%、30.26%、20.62%、7.12%。并根据武夷山国家公园试点的现状,有针对性地提出对策与建议,可为武夷山国家公园后期的规划、管理提供参考。     

澳洲坚果优良品种筛选、繁殖和丰产技术研究通过结题验收

2001年2月9日，云南省科技厅委托云南省农垦总局主持，邀请有关专家7人组成验收委员会，在景洪市 对云南省热带作物科学研究所承担的省科技攻关计划课题《澳洲坚果优良品种筛选、繁殖和丰产技术研究》进行结题验收。课题组成员经过6年试验研究，探索出了澳洲坚果最隹的嫁接和扦插方法，使嫁接成活率达71.7%～ 86.7%，扦插生根率达70%，并成功获得了组培苗。在良种筛选中，掌握了省内8个不同生态环境15个品种的生长性状和初期产量水平，初步选出适宜云南热区推广种植的优良品种4个；初步总结出澳洲坚果速生丰产的栽培管理措施。查实了澳洲坚…     

<Emphasis Type="Italic">Ophiostoma</Emphasis> species associated with bark beetles infesting three <Emphasis Type="Italic">Abies</Emphasis> species in Nikko,Japan

Ophiostoma species were isolated from bark beetles and Abies mariesii, A. veitchii and A. homolepis attacked by the beetles in Nikko, Tochigi, central Honshu, Japan. One to two Ophiostoma species were frequently isolated from each species of bark beetle. Ophiostoma subalpinum was the most common associate of Cryphalus montanus. Ophiostoma sp. B as well as O. subalpinum was a common fungus associated with Polygraphus proximus. Ophiostoma europhioides was isolated from Dryocoetes hectographus and D. autographus as one of the common associates. Ophiostoma sp. J and Ophiostoma sp. S were frequently isolated from D. autographus and D. striatus, respectively. These fungi seem to have specific relationships with particular bark beetles. Ophiostoma sp. B, Ophiostoma sp. J and Ophiostoma sp. S have unique morphological characteristics and appear to be new species. Five trees of A. veitchii, approximately 43 years old, were inoculated with five Ophiostoma species to assess the relative virulence of the fungi. Ophiostoma subalpinum, Ophiostoma sp. B, and O. europhioides had relatively higher virulence than the other species studied.     

Improving the evaluation of multiple-dowel-type connection strength

Our study focuses on predicting the ultimate short-term load carrying capacity of timber-to-timber connections with dowel-type fasteners. The wide range of possible configurations in practice makes the resolution of these values by tests unrealistic. Moreover, different current regulations do not consider some specific failure mechanisms. In many countries, the reduction of resistance involved by this phenomenon is taken into account by considering an effective number of dowels (n_ef) smaller than the actual number of dowels (n) in the connection. However, these different regulations disagree on the values of n_ef and on other points (spacing, partial coefficient of security, formulas). These discrepancies in design rules invite the fundamental research on this topic and, therefore, new methods are sought in order to estimate the load carrying capacities of the connections. In the light of these, our approach consists of predicting the load carrying capacity with the neural network numerical tool. The results obtained by this analysis tool are satisfactory, although the model remains complex. Subsequently, we focus on the simplification of this numerical model with classical regression techniques in order to implement it in a design code.     

Parasitic Ichneumonoidea on the horse chestnut leaf miner, Cameraria ohridella (Lepidoptera: Gracillariidae) in Slovakia

Parasitic Hymenoptera from the suprafamily Ichneumonoidea attacking the horse chestnut leafminer Cameraria ohridella Deschka & Dimic (Lepidoptera: Gracillariidae) were studied in southwest Slovakia during 2000 and 2001. The search for such species resulted in the determination of eight ichneumonid species, Gelis agilis (Fabricius), Itoplectis alternans (Gravenhorst), I. clavicornis (Thompson), I. maculator (Fabricius), Scambus annulatus (Kiss), S. brevicornis (Gravenhorst), Zatypota percontatoria (Müller), Adelognathus sp. and a braconid Colastes braconius Haliday. The most abundant species was S. annulatus. All these species recorded are polyphagous and often facultative hyperparasitoids, except C. braconius, which departs from this norm in not being hyperparasitic. The presence of more diversified native parasitoids and hyperparasitoids from the Ichneumonoidea predicate a slow successive adaptation of the parasitoid fauna to the invasive host, Cameraria ohridella.     

Insecticidal activity of certain medicinal plants

The methanol extracts of eight species of medicinal plants were tested for insecticidal activity in third instar larvae of Egyptian cottonworm (Spodoptera littoralis). All extracts showed a certain degree of larval toxicity. The extracts of Ocimum basilicum, Origanum majorana and Salvia officinalis appeared to be highly toxic. The extracts significantly affected the growth indexes [relative growth rate (RGR), efficiency of conversion of ingested food (ECI), efficiency of conversion of digested food (ECD)].     

A new norlignan from Taxodium ascendens

A new norlignan, (2R,3R,4S,5S)-2,4-bis(4-hydroxyphenyl)-3,5-dihydroxy-tetrahydropyran (1), together with 9 known compounds were isolated from the branches and leaves of Taxodium ascendens. Their structures were mainly determined on the basis of MS, IR, 1D and 2D NMR spectral evidences. Methanol extract showed inhibitory activity on carbonic anhydrase II with an IC₅₀ value of 4.27 µg/ml, acetone extract and methanol extract inhibited activity of cathepsin B with IC₅₀ values of 2.12 and 3.71 µg/ml, respectively.     

Decomposition and nutrient loss from prunings of different contour hedgerow species in tea plantations in the sloping highlands of Sri Lanka

Contour hedgerows of multipurpose tree species in the sloping tea lands of Sri Lanka are expected to reduce soil erosion and also add significant amounts of plant nutrients to the soil via periodic prunings. The objective of this experiment was to characterize the biomass decomposition pattern and quantify the amount of nutrients added through prunings of six tree species (Calliandra calothyrsus, Senna spectabilis, Euphatorium innulifolium, Flemingia congesta, Gliricidia sepium and Tithonia diversifolia) currently being used in hedgerows associated with tea. Withered leaf and stem prunings (50 g) were enclosed in 2-mm litter bags, placed at 5-cm depth and retrieved after one, three, six, nine and 12 weeks. Loss of initial dry weight, N, P and K was measured. Single exponential decay function adequately described both dry weight and nutrient loss. Tree species differed significantly in their rate of breakdown with decomposition constants (k) varying from 0.0299 to 0.2006 week⁻¹ for leaves and from 0.0225 to 0.0633 week⁻¹ for stems. Gliricidia showed the highest k for leaves with the rest in the following descending order: Senna > Tithonia ≥ Euphatorium > Calliandra > Flemingia. A similar pattern was observed for loss of all nutrients with Calliandra and Flemingia always having lower k values than the rest. Although N immobilization was not observed, immobilization of P and K was observed during the first week of incubation in some species, particularly in stem prunings. Annual biomass of prunings differed significantly between tree species in the following descending order: Calliandra > Senna > Flemingia > Tithonia > Gliricidia > Euphatorium. Calliandra added the greatest amount of nutrients annually to the soil with Euphatorium adding the least. Calliandra prunings provided the annual total K requirement and 49% of the N requirement of mature tea. However, none of the species provided more than 5% of the P requirement. It is concluded that among the tree species tested, Calliandra and Flemingia are the most suitable for contour hedgerows in tea plantations of this agroclimatic region because of their higher soil nutrient enrichment capacity and slower decomposition rates which would minimize leaching losses. This revised version was published online in June 2006 with corrections to the Cover Date.     

<Emphasis Type="Italic">Bursaphelenchus mucronatus</Emphasis> (Nematoda: Aphelenchoididae) vectored by <Emphasis Type="Italic">Monochamus </Emphasis><Emphasis Type="Italic">urussovi</Emphasis> (Coleoptera: Cerambycidae) in Hokkaido,Japan

Bursaphelenchus mucronatus Mamiya et Enda has been recovered for the first time from adults of the cerambycid beetle, Monochamus urussovi (Fischer), in Hokkaido, Japan. The nematode was also recovered from the inner bark of Picea jezoensis (Siebold et Zuccarini) Carrière and Abies sachalinensis (Fr Schmidt) Masters infested with M. urussovi larvae. PCR–RFLP analysis indicated that B. mucronatus in Hokkaido is the European type.     

Potential to harness superior nutritional qualities of exotic baobabs if local adaptation can be conferred through grafting

Baobab leaves form an important part of the local diet in Sahel countries and elsewhere in Africa. Existing leaf nutritional data and agroforestry performance information are based solely on Adansonia digitata L., the baobab of continental Africa. The introduction potential of Adansonia species from the center of diversity in Madagascar and from Australia remains untapped. To assess this potential, the mineral contents and B₁ and B₂ vitamin levels of dried baobab leaves were determined for five-year old trees of A. digitata, A. gibbosa (A. Cunn.) Guymer ex D. Baum, A. rubrostipa Jum. & H. Perrier (syn. A. fony Baill.), A. perrieri Capuron and A. za Baill. grown in an introduction trial in Mali. Nutritional data were evaluated against survival and vigor to identify promising germplasm. Leaf vitamin and crude protein contents were highest in the Madagascar species, especially A. rubrostipa (B₁ 88 mg 100 g⁻¹, B₂ 187 mg 100 g⁻¹, protein 20.7% dry weight). However, the local species far outperformed the introductions in survival, tree height, basal diameter and resistance to termites. We suggest grafting as a way of harnessing the vigor of well-adapted local baobab varieties to the superior nutritional profiles of A. rubrostipa and others. Cross-species grafting tests in Adansonia were successful, thus creating new agroforestry possibilities with different scion/rootstock combinations.     

Trees and shrubs as sources of fodder in Australia

Experience with browse plants in Australia is briefly reviewed in terms of their forage value to animals, their economic value to the landholder and their ecological contribution to landscape stability. Of the cultivated species only two have achieved any degree of commercial acceptance (Leucaena leucocephala and Chamaecytisus palmensis). Both of these are of sufficiently high forage value to be used as the sole source of feed during seasonal periods of nutritional shortage. Both are also leguminous shrubs that establish readily from seed. It is suggested that a limitation in their present use is the reliance on stands of single species which leaves these grazing systems vulnerable to disease and insects. Grazing systems so far developed for high production and persistence of cultivated species involve short periods of intense grazing followed by long periods of recovery. Similar management may be necessary in the arid and semi-arid rangelands where palatable browse species are in decline.     

Rehabilitation of diseased cacao fields in Peru through shade regulation and timing of biocontrol measures

The objective of this case study was to test the effectiveness of biocontrol for the rehabilitation of abandoned, diseased (moniliasis, witches' broom and black pod) cocoa and to develop testable hypotheses regarding the effect of shade and biocontrol timing. Three trial fields differed in their shade regimes. Biocontrol was administered starting either at flowering or pod filling. Disease incidence and yield were compared with cultural control alone. Biocontrol reduced moniliasis from 49% to 25%, independent of the shading regime and application time. Witches' broom was most severe without shade and unaffected by biocontrol. No significant effects on black pod were observed. Although biocontrol increased percentage healthy fruit independent of shading and timing, only the shaded plot with biocontrol from flowering onwards responded with increased yield. Our hypothesis is: 'In the rehabilitation of abandoned cacao, only fields under sustainable shade management and early onset of biocontrol can realise their production potential.' This revised version was published online in June 2006 with corrections to the Cover Date.