新疆农牧区贫困户参与旅游精准扶贫行为

以新疆农牧区贫困户为研究对象,采用计划行为理论模型以及双槛模型的方法,研究了影响贫困户的参与行为,以期提出减贫路径。结果表明:农牧民是否参与旅游精准扶贫的行为前提为是否有一定的参与意愿。贫困户的个人特征中,家庭创业、人均纯收入、通用电对参与旅游精准扶贫产生了正向的促进作用,与村主干路距离、外出务工人员、思想动力不足导致的贫困对参与旅游精准扶贫产生了负面影响;在行为规范中,指令性规范、示范性规范、合作态度对旅游精准扶贫中的前景看好、知觉行为控制力对农牧民参与旅游精准扶贫产生了正面影响。     

Impacts of water resource planning on regional water consumption pattern: A case study in Dunhuang Oasis,China

Water resources are critical for the existence and development of oases in endorheic basins. Thus, to enable sustainable development, it is fundamentally important to understand how to allocate and use these resources in a reasonable way. We therefore simulated and analyzed changes in water consumption pattern within the Dunhuang Oasis of China under three scenarios using a system dynamic model that corresponds to different water consumption pattern. This was done to assess the impacts of regional water resource planning (comprehensive planning of the rational use of water resource and protection of ecosystem services in the Dunhuang Basin) on water consumption pattern within the Dunhuang Oasis. The first of these, Scenario 1, is a baseline in which the status quo is maintained, while Scenario 2 incorporates the comprehensive effects of agricultural water-saving irrigation measures with an inter-basin water diversion project, and Scenario 3 focuses on ecological rehabilitation. In the baseline Scenario 1, the total water consumption within the Dunhuang Oasis increased progressively while agricultural water consumption remained extremely high and threatened overall ecological security. In contrast, Scenario 2 would decrease agricultural water consumption by almost 5.30×10⁷ m³ following the implementation of water-saving practices. The additional water allocated from an inter-basin water diversion project would play an important role in alleviating ecological strain on the oasis. Finally, in Scenario 3, the total irrigated land must be decreased to 20.6×10³ hm² by 2025 assuming that water supply for ecosystem restoration would be at least 50% of the total consumption. Although water resource planning plays a very important role in alleviating the ecological water crisis within the oasis, it is necessary to consider the suitable scale of oasis with regard to current water consumption pattern.     

茶树GGPS基因家族的克隆、生物信息学和表达分析

牻牛儿基牻牛儿基焦磷酸合酶(Geranylgeranyl diphosphate synthase,GGPS)是萜类合成途径的结构酶,对植物生长发育具有重要意义。本研究通过RACE和RT-PCR方法克隆得到5条潜在的茶树GGPS序列,分别命名为CsGGPS1-4和CsGGPS9,其中CsGGPS9存在3条等位基因,分别是CsGGPS9-1、CsGGPS9-2和CsGGPS9-3,在系统进化树上与其他基因分成两支。蛋白质序列分析表明,茶树GGPS家族成员都具有polyprenyl_synt结构域,不存在信号肽序列。亚细胞定位预测结果显示,CsGGPS1、CsGGPS2和CsGGPS4定位在叶绿体上,CsGGPS3和CsGGPS9定位在线粒体上。通过Swiss Model进行三维建模,结合"three-floor"模型对茶树GGPS家族成员的功能进行预测,预测结果显示,CsGGPS1、CsGGPS2和CsGGPS4是GGPS;CsGGPS3是异源二聚体形式的牻牛儿基焦磷酸合酶的小亚基;CsGGPS9的催化主产物是碳链数大于30的异戊烯基焦磷酸。q RT-PCR分析表明,CsGGPS1整体表达丰度较低,仅在一芽二叶中表达量稍高;CsGGPS2在茶树各个组织中均有表达,在花中表达量最高,且花发育过程中表达量先上升后下降;CsGGPS3在叶和幼根中的表达量高于花,花发育过程中表达平稳;CsGGPS4在茶树各个组织中表达量数值相近,在花发育过程中表达量变化趋势与CsGGPS2相同;CsGGPS9的表达量在成熟叶中显著低于幼嫩叶片。     

基于ARIMA模型的我国大豆单产预测分析

在我国大豆单产光合潜力和"农业生态区划"(AEZ)潜力基础上,运用ARIMA(自回归单整移动平均)模型预测了2020年前我国大豆单产。结果表明:我国大豆单产最大潜力为3 400 kg·hm~(-2),而2017、2018、2019和2020年单产将分别为1 899,1 926,1 954和1 982 kg·hm~(-2),分别是最大潜力的55.85%、56.65%、57.47%和58.29%。这意味着:未来提高我国大豆单产尚有较大空间,应保持高产耕地生产力与改良中低产田土并重。研究结果旨在为我国大豆生产提供决策参考信息。     

吉林省半干旱区45年气候变化及基于Hybrid-Maize的玉米品种熟期选择

本研究分析吉林省西部半干旱地区1971~2015年气候要素变化特征,用Hybrid-Maize模型估算该区域品种熟期(GDD)不同玉米品种的产量潜力。结果表明,该区域近45年温度、降水和日照时数年均变化与玉米生长季变化趋势类似,但生长季变幅与年均值变幅差异较大,且生长季时间序列上突变点明显不同,温度和降水具有滞后性,日照时数具有超前性,其中,生长季温度增幅高于全年温度增幅,但突变时间滞后10年;长期年均降水波动性大,而生长季降水较全年呈现明显上升趋势,且2010年以来生长季均为较湿润阶段。生长季日照时数减少比年均减少趋势慢,为其下降速率的40%。以4月30日为适播期,种植密度60 000株/hm~2时,乾安、洮南、前郭推荐熟期相对较长品种(GDD=1656-1672),扶余、镇赉推荐熟期相对较短品种(GDD为1606和1500)。洮南、扶余、前郭玉米R/V值接近1.0,乾安和镇赉R/V超过1.15,利于获得较高产量。     

Drivers of Setaria pumila (Poir.) Roem. et Schult growth and impact on forage quality in lowland Switzerland meadows

Invasive grasses (especially Setaria pumila (Poir.) Roem. et Schult) increasingly threaten meadows and pastures as a consequence of human impact and climate change. We conducted a study in 2012 and in 2013 to better understand the growing cycle and the influence of S. pumila on forage quality of lowland meadows. We observed a rapid increase of S. pumila presence and phytomass on the southern side of the Alps across the growing season. We measured (i) above‐ground phytomass, with a modified Corral‐Fenlon method; (ii) botanical composition using the linear point quadrat method; and (iii) grassland chemical composition by NIRs (near‐infrared spectroscopy) analyses. To test the hypothesis that S. pumila summer growth is related to specific climatic conditions, meteorological data (temperature, precipitation and evapotranspiration) were collected from meteorological stations near the study sites. Total phytomass was sorted into S. pumila and other species. We used a generalized linear mixed models (GLMM) and found the abundance of S. pumila to be inversely correlated with rainfall and the presence of other species, but positively correlated with temperature increase. The increase of S. pumila above‐ground phytomass production was linked to a reduction of forage quality.     

基于生态文明的半干旱区土地资源综合承载力评价研究

土地资源面积的有限性,位置固定性和区域差异性,造成了其供给稀缺性;而土地资源具有养育、支撑、资源和资产等功能,其需求旺盛;土地资源供给的稀缺性与社会需求的无限性之间存在矛盾。笔者运用经济学的总需求-总供给模型(AD-AS模型),立足生态文明角度,从供求方面对区域土地资源承载力进行探讨,以山西省大同市为案例区。研究结果表明:(1)由耕地需求量、建设用地需求量和生态用地需求量构成的土地资源综合承载力总需求,2011—2015年大同市土地综合承载力总需求分别为0.5309、0.5542、0.5770、0.5797和0.6030;其总体趋势增加;(2)由耕地支撑能力、建设用地支撑能力和生态支撑能力构成的土地综合承载力总供给,2011—2015年大同市土地综合承载力总供给分别为1.423、1.466、2.104、1.531和1.509;(3)2011—2015年大同市土地综合承载力处于超载,2013年超载最大,2015年超载最小,说明大同市的土地资源承载力超载现象在改善。运用此方法进行土地资源综合承载力评价,在土地资源承载力研究中更为科学和合理,使得人们更为关注生态文明,为建立社会、经济、生态和谐的人地关系提供了新的依据。     

基于生理发育时间的水稻发育期预测方法

水稻发育期模型研究是开展现代农业气象服务工作的基础。基于作物生理发育时间守恒原理,综合考虑温度和日长因子对水稻发育期的影响,利用云南省12个农气观测站2011—2014年水稻发育期观测和地面气象观测资料,分别构建并验证了适用于籼稻种植区和粳稻种植区的发育期预报模型。结果表明,2套模型在全发育期和各发育阶段的预报值与观测值模拟效果总体较好,平均全发育期RMSE值为7.47,RE值为7.99%,粳稻模型和籼稻模型的RE值分别为6.49%和9.5%,粳稻区模拟效果优于籼稻区。模型生物学意义明确、参数通用性强,适用于农业气象业务服务中水稻发育期预测,具有推广应用价值。