基于生态位模型的岷江上游典型县域乡村聚落用地适宜性评价

乡村聚落用地适宜性研究不仅有利于揭示人类活动与生态环境、社会经济之间的匹配程度,亦能为乡村聚落重构及国土空间优化提供科学依据。该研究基于乡村地理学、景观生态学及生态位理论方法,以岷江上游典型县域理县为研究区,采用遥感影像、社会经济统计、土地利用现状等多源数据,通过景观格局分析、数理统计分析、GIS空间分析等技术手段,首先判识了理县乡村聚落用地适宜性研究的最佳空间尺度,然后借鉴生态位适宜度测算模型,对理县乡村聚落用地适宜性进行评价。结果表明:1)根据8个乡村聚落景观指数对20种乡村聚落空间粒度的响应变化情况,综合8个景观指数的第一尺度域判识得到理县乡村聚落景观格局及适宜性研究的最佳空间尺度为60 m;2)在60 m最佳空间尺度下,利用GIS空间叠加分析得到理县乡村聚落适宜性土地面积占县域国土面积的4.58%,主要集中分布于东部、东北部乡镇及杂谷脑河下游、317国道沿线;3)理县乡村聚落低度适宜区主要位于水源保护区、生态保护区及地质灾害多发区,不适于人类长期生存发展;中度适宜区在自然资源、区位等方面具有相对优势,特色产业突出,具备现代农业发展潜力;高度适宜区在区位、经济、自然与文化资源等方面具有明显优势,乡村发展功能较齐全,应作为乡村人口和产业的主要聚集区;中、高度适宜区是理县乡村振兴战略的主要支撑空间。     

不同来源海洋弧菌微生物被膜对厚壳贻贝稚贝附着的影响

为探讨广泛存在于近海环境中海洋弧菌和贝类附着的相互作用关系,实验从自然微生物被膜和厚壳贻贝成体肠道内分离了海洋弧菌,测定其种属及亲缘性,调查了这些不同来源弧菌形成的微生物被膜与厚壳贻贝稚贝附着的调控作用。结果显示,测试弧菌形成的微生物被膜密度随着初始细菌密度的增加呈现不同程度的增加。源于自然微生物被膜和贻贝肠道内的10株弧菌均能显著促进厚壳贻贝稚贝的附着,不同菌株形成微生物被膜的诱导活性存在显著差异,附着率变化范围为17%~67%,其中稚贝在Vibrio sp.17微生物被膜上的附着率为67%±2%。微生物被膜对稚贝附着诱导活性与被膜密度呈显著相关性,其中弧菌V.crassostreae ECSMB14106的相关性系数最高,为0.8992。此外,微生物被膜的诱导活性与弧菌的来源无关。本实验初步探明了海洋弧菌对厚壳贻贝稚贝附着的影响,有助于进一步理解微生物被膜调控厚壳贻贝的附着分子机理。     

Development of ceramic settlement devices for coral reef restoration using <Emphasis Type="Italic">in situ</Emphasis> sexual reproduction of corals

A ceramic coral settlement device (CSD) was developed to raise juvenile corals in situ in preparation for transplantation. The CSD is designed to be deployed in the water before mass spawning of corals, allowing larvae to settle and grow on the CSD before it is fixed to the reef structure. CSDs were aggregated and fixed on 0.2-m² frames (either 648 or 720 CSDs per frame) and deployed in the Sekisei Lagoon around the full moons of April and May in 2002. Seven frames were collected in August 2002 and settled corals were counted in the laboratory. The maximum number of coral colonies settled on CSDs in one frame was 617, with 94% belonging to the genus Acropora. The aggregated CSDs successfully functioned as a coral settlement substratum, with more appropriate arrangement of CSDs on the frame, enabling greater exposure to sunlight and currents, which is expected to increase the amount of settlement.     

完善省级农业科研单位资金结算中心的探讨

成立资金结算中心对省级农业科研单位经济的发展具有重要的意义。文章首先对资金结算中心的运作方式进行了介绍,并根据江西省农业科学院的实际情况,阐述了省级农业科研单位成立资金结算中心的目的及取得的成绩;然后分析了资金结算中心存在的问题;最后结合具体情况提出了完善资金结算中心的资金管理和资金融通的管理措施。     

气力辅助充种式花生精量排种器设计与试验

针对花生播种向精准、高速方向发展过程中高速作业状态下花生种子充种效果差的问题,设计了一种气力辅助充种式花生精量排种器,重点设计了排种器排种盘结构和气力辅助充种结构。针对颗粒尺寸大、质量大的花生种子,通过对花生种子在排种器中堆积现象与充种时间进行分析,得出花生高速排种充种过程需增强充种性能,从而提高充种效率。通过对花生种子进行充种原理分析,阐明花生种子充种过程中种子与排种器的运动关系与受力关系,分析充种过程影响因素。通过设计带有导种槽的排种盘和带有辅助吹种型孔的辅助充种结构,分析计算排种盘吸种孔、导种槽的关键结构参数以及辅助吹种型孔参数与排列方式。以充种合格率和充种漏充率为指标,进行三因素三水平组合试验,对试验结果进行多元回归分析,以最优目标进行优化,确定排种盘最佳参数组合为排种器吸种负压5.156 kPa、花生高速播种机前进速度8.007 km/h、扰动吹种正压1.149 kPa,此时,花生充种合格率为95.84%、漏充率为4.06%,能够实现花生种子有效充种。     

含沙水磁化处理减缓滴头堵塞机理研究

为探究含沙水磁化处理对悬浮泥沙在滴灌管网中沉降的影响,揭示含沙水磁化处理对滴头堵塞的减缓机理,以内镶贴片式迷宫流道滴头为研究对象,设置4种磁化强度(0、0.2、0.4、0.6 T)和4种粒径级配(0～0.100 mm、0.075～0.100 mm、0.038～0.075 mm、0～0.038 mm)的泥沙,泥沙质量浓度...     

Structural Design of the Multi_Purpose Building for the Public Security Bureau,Xin Xiang City Henan Province

This paper introduces the methods of reducing and controlling differential settlement by changing the length and load_bearing capacity of the piles,and other means,rather than setting settlement gaps between the main building and the podium structure.By using these methods,the size of differential settlement observed is only 1mm.Because of the building with a tower 45m high,the earthquake magnification factor is taken as 3 with considering whiplash effect.     

Differing environmental drivers of settlement across the range of southern rock lobster (Jasus edwardsii) suggest resilience of the fishery to climate change

Temporal and spatial trends in settlement of the southern rock lobster, Jasus edwardsii, were examined to identify the influence of environmental variables over different spatial scales. Settlement data were collected from 1994 to 2011 along the Southern Australian and New Zealand coasts. We identified common settlement trends at a regional scale (100–500 km): the magnitude of settlement at sites from South Australia (SA) and Victoria (VIC) were similar, but different to sites in Tasmania (TAS). In New Zealand, three spatial regions were identified: northern (NNZ), middle (MNZ) and southern regions (SNZ). Higher settlement in SA, VIC and MNZ occurred in years with higher rainfall and storms in spring and El Niño conditions. In TAS and SNZ, higher settlement occurred during La Niña conditions. These results suggest that settlement over regional scales is modulated by oceanic processes, but outcomes vary between regions. At a local scale, a higher wave period and wind relaxation were relatively more important than the sea surface temperature (SST) in SA and VIC. In TAS, the current velocity also influenced the strength of settlement. However, much of the local settlement variability was not explained by the models suggesting that settlement in J. edwardsii is a complex process where larval behaviour, biological factors and oceanographic processes interact over different scales. The apparently complex processes affecting settlement showed that environmental conditions that reduced settlement strength in one region of the fishery often increased settlement strength in other regions. This could provide resilience to climate change at the stock level.     

牧民定居后草地畜牧业生产经营优化模式研究

运用系统工程的原理和方法,遵循生态经济规律和资源高效持续利用的原则,研究提出了牧民定居后新的生产方式下新疆天山北坡中段草地畜牧业生产经营优化模式(暖季放牧、冷季舍饲 放牧).该模式能有效缓解草畜矛盾,人均收入比现行系统提高了63.39%,且使天然草地的生产能力、能量转化效率都有大幅度提高.     

岷江上游干旱河谷区退耕还林还草的社会经济影响

利用遥感资料和GIS技术,研究1999-2009年岷江上游干旱河谷区聚落生态位内部耕地、林地和草地变化动态,基于主成分分析法,建立退耕还林（草）的社会经济影响指数,评估1999年以来岷江上游退耕还林（草）的社会经济影响。1999~2009年聚落生态位内部耕地减少38.44%,而草地增长70.30%,林地增长53.20%;不同海拔耕地面积均呈不同程度的减少,海拔2 001~3 000 m退耕较多,占退耕总量的85%;不同坡度的耕地面积均呈减小趋势,耕地减少量随坡度增大而增加;1999~2014年岷江上游退耕还林还草的社会经济影响指数介于-0.70~1.48,整体呈先下降后上升趋势。岷江上游退耕还林还草的社会经济影响日益凸显,对当地的社会稳定和经济发展具有促进作用。岷江上游聚落区具有低阈值粮食流通,高风险粮食危机的显著特征,耕地过度非农化将制约退耕还林还草社会经济效益的持续稳定增长,新一轮退耕还林应警惕耕地过度非农化潜在的粮食安全风险。