滇中冷凉山区不同播期反季花椰菜产量效益分析

为摸索滇中高海拔冷凉山区反季节栽培花椰菜的最佳播期以集成高效栽培技术推广应用,于2017—2018年选择海拔2250 m的云南省峨山县塔甸镇大西村地块进行9个播期的2年随机区组试验。结果表明,花椰菜生育期随播期推迟而延长,而花球采收期除播期7月10日外随播期推迟而逐渐增长;花椰菜株高、外叶数、开展度、球高、球径和单球重等农艺性状有随播期延迟呈现先逐渐减小而后又逐渐增大的趋势;莲座期黑腐病和霜霉病的病情指数随着播期的延迟呈现先逐渐升高而后又逐渐下降的趋势;花椰菜小区产量随着播期的延迟呈现先逐渐下降而后又逐渐提高的趋势,播期4月20日和4月30日与其余7个播期产量之间的差异达极显著水平。综合花椰菜在冷凉山区反季节栽培的生产实际和各播期产量产值及商品性表现,推荐滇中高海拔冷凉山区反季节栽培花椰菜的最佳播期为4月20—30日。     

黄土低山丘陵及坨甸草原区风蚀规律的研究

本文通过对黄土低山丘陵及坨甸草原区248个风蚀图斑资料的分析,运用线性模型理论,对此地区的风蚀规律进行了研究。获得了下垫面各因素与风蚀量关系的数学模型。找出了影响风蚀的主导因素,并系统阐述了植被覆盖度和土地利用类型对风蚀量大小的影响,且与水蚀规律进行了比较分析。     

三峡库区农村沼气综合利用途径与思考

三峡库区资源丰富,但库区农村存在资源利用不合理、能源紧缺的情况.库区的气候及资源是发展沼气的有利条件.沼气是一项投资少,见效快,一次投资长期受益的好项目;是能够解决库区农村燃料短缺,提高用能品质,促进农民增收节支的有效途径,并且是保护生态改善农村生活环境,促进库区农村生态经济可持续发展的有效举措.     

林木抗旱性生理指标及其在干旱区造林中应用研究

<正> 中国干旱半干旱区面积占全国面积的52.5%,半壁河山是以水分胁迫为主导限制因子的特殊生态区。为了提高这一地区的造林质量,选择旱生和抗旱性强的树种造林是主要造林技术之一。对于如何评价和比较林木的抗旱性,传统方法多采用对林木生态环境因子及对林木生     

Regulation of MMP-2 and TIMP-3 expression by uPA signal transduction system in human bone giant cell tumor

AIM: To study effects of urokinase-type plasminogen activator (uPA) signal transduction on expression of matrix metalloproteinase-2 (MMP-2) and tissue inhibitor of matrix metalloproteinase-3 (TIMP-3) in giant cell tumor of bone (GCT). METHODS: Expression of uPAR, MMP-2 and TIMP-3 in GCT tissue was detected by immunohistochemistry. Phosphorylation level of mitogen-activated protein kinase (p44) in uPA/uPAR signal pathway in cultured GCT cells was detected by immunoprecipitation. The expression of MMP-2 and TIMP-3 in cultured cells after treatment with uPA-ATF or anti-uPAR antibody was also detected by Western blotting. RESULTS: 1) Urokinase-type plasminogen activator receptor (uPAR) was positive on the cell membrane and in cytoplasm of some mononuclear stromal cells (MSCs) and multinucleated giant cells (MGCs); 2) MMP-2 was positive in the cytoplasm and on the cell membrane of almost all of MSCs and some of MGCs. The polar distribution of MMP-2 in the cytoplasm of MGCs was especially obvious; 3) The expression of TIMP-3 of some MSCs and MGCs in GCT was much lower than MMP-2. The positive signal also showed a prominent polarity; 4) After treatment with uPA-ATF, the phosphorylation level of p44 in GCT cultured cells was much higher than the control. Addition of anti-uPAR antibody in the cells remarkably down-regulated the phosphorylation level of p44 as compared with the control group, suggesting that uPA-ATF participates cell signal transduction and this reaction can be inhibited by anti-uPAR antibody; 5) uPA-ATF cell signal pathway up-regulated expression of MMP-2 and TIMP-3, while anti-uPAR antibody down-regulated the expression of MMP-2 and TIMP-3. CONCLUSION: These results demonstrate for the first time that uPA-ATF directly regulates the expression of MMP-2 and TIMP-3 by signal transduction pathway, and the over-expression of MMP-2 and TIMP-3 may play an important role in local osteolysis of GCT.     

大熊猫放归计划框架与操作程序初探

本文依据IUCN/RSG关于物种放归的标准,借鉴麋鹿、普氏野马和扬子鳄等物种放归的成功经验,提出了大熊猫放归的基本内容和程序,即:足够的生物学和生态学的知识;适宜栖息地的选择;充足的释放动物种源;在实验的基础上,经过有效的工作小组的分析和综合,从潜在的栖息地的评估和选择,到小规模的释放试验性项目,长期监测,发展到正式放归项目实施。     

野外放归大熊猫肠道菌群变化的研究

对四川卧龙中国保护大熊猫研究中心的一只野外放归亚成体大熊猫肠道菌群的组成和季节变化规律进行了研究,同时与其圈养双胞胎兄弟的肠道菌群进行了比较。从放归大熊猫粪便中分离出17种肠道菌,优势菌群为肠杆菌、肠球菌和乳杆菌。与圈养大熊猫相比,放归大熊猫肠道菌群中优势菌群的种类未发生改变,但是肠球菌数量增加,肠杆菌和乳杆菌的数量减少。研究发现放归大熊猫肠道菌群中的肠杆菌和肠球菌的数量随季节变化有较大波动,乳杆菌的数量随季节变化波动不大;而圈养大熊猫三种优势菌的数量随季节变化波动都不大。     

The value of vegetation cover for ecosystem services in the suburban context

Latin-American cities can be characterized by dynamic processes of urbanization that encroach upon the natural and semi-natural surrounding landscapes. Our study presents the effects of landscape development, transformed from semi-natural conditions into a mostly disperse suburban settlement. We explore the impact that this transformation has had on this context by three ecosystem services that regulate rainwater runoff, enhance microclimate conditions and help to improve air quality by monitoring vegetation cover. We have designed a spatio-temporal hierarchical analysis which employs remote sensing techniques to capture the structural changes of this landscape over long, medium and short term scales on two spatial levels. This methodological approach was tested in the Metropolitan Area of Santiago (MAS) as case study area. Despite of the increase in impervious surfaces due to urban processes, there has also been an increase in vegetation cover, which has led to an improvement in the provision of the above-mentioned ecosystem services. Hence, if diverse urbanization processes continue and they are coupled with an increase in vegetation cover, the provision of ecosystem services could also expand. This phenomenon can be observed in some areas, where public and private green spaces are created and maintained. Our data analyses give evidence that certain types of suburban areas which increase the share of vegetation cover can provide daily ecological benefits for urban neighborhoods, and beyond, for adjacent areas. Moreover, suburban development can successfully provide ecological benefits to citizens. Such processes can only be ecologically sustainable if the composition of vegetation is well-adapted to the regional climatic conditions.     

甘肃黄河三峡景区旅游资源空间结构研究

旅游空间结构是旅游系统功能组织方式在空间上的投影或表象,其空间结构是否合理直接影响到旅游目的地旅游业的发展态势。黄河三峡景区凭借其丰富、独特的资源优势,已成为黄河流域最著名的景区之一。受河谷地带的基础性影响,其资源类型、空间结构、游览线路等表现出典型的空间特征,深刻影响着景区旅游空间格局。借助Arc GIS空间网络分析模块和Excel平台,对黄河三峡景区旅游资源空间结构进行定量分析,发现旅游资源空间分布呈集聚态势,基尼系数高达0.755,分布均匀度仅为0.245;采用最邻近指数和Voronoi多边形的变异系数分析空间分布类型;用地理集中指数和基尼系数分析空间分布均衡性,运用β指数、γ指数和α指数刻画空间连接度。结果表明:景区内旅游资源的空间分布均匀度低,呈多中心集聚分布。这既有利于景区内各景点之间的整合和旅游规模效应的产生,又可以减弱区间屏蔽作用等外部不经济性。景区内各景点之间的交通网络密度低,空间联系较弱,通达性较低。各景点之间的直接连接较少,旅游路线多为单线往返,缺少串联各个景点的环形线路。     

地表火对宝天曼栎类森林生态系统服务功能的影响研究

2008年4月至2010年6月采用时间序列代替空间序列的方法,对宝天曼栎类森林生态系统服务功能受地表火影响在不同时间的涵养水源、保育土壤、固碳释氧、生物保育、积累营养物质、负离子提供和森林病虫害防治等7个方面进行了初步评估。结果表明,地表火干扰造成宝天曼栎类森林生态系统服务功能损失的价值在时间序列上依次为1年是24.95万元.hm-2,5年是11.68万元.hm-2,10年是4.91万元.hm-2,15年是0.68万元.hm-2;各项服务功能价值量损失排序为保育土壤>涵养水源>病虫害防治>固碳释氧>积累营养物质>净化大气>生物保育,其中保育土壤和涵养水源两项的损失占总损失量的70%左右,这表明地表火主要影响宝天曼栎类森林生态系统中的保育土壤和涵养水源功能。