Understanding utilitarian and hedonic values determining the demand for rhino horn in Vietnam

We examined utilitarian and hedonic values as motivations for rhino horn use in Vietnam. We also evaluated consumers’ response to consequences of the illegal trade in behavior modification campaigns and the likely outcome of a legalized trade. The most prevalent use was for treatment of hangovers indicating utilitarian values, although difficult to separate from the hedonic value in projecting success in business. A ritualized way of honoring terminally ill relatives represented a hedonic value replacing belief in effective treatment. Demand reduction campaigns need to appropriately reflect all relevant values determining specific uses. The plight of rhino populations, Vietnam’s penal code, and the possible contribution to international crime mattered little to consumers. Horn from wild rhino was preferred over farmed, and respondents would demand more if available in a legalized trade. This suggested that a legalized trade could maintain or even increase demand for poached rhino horn.     

耳背包埋蟾酥和雄黄法治疗猪高热综合征

利用传统中药蟾酥和雄黄进行耳背包埋法,治疗猪高热综合征,结果 7 d左右病猪体温恢复正常,10 d左右耳背包埋药物处痂皮开始脱落,15 d左右23只病猪全部恢复健康。应用此法会造成病猪耳朵的脱落或穿孔,影响动物福利,今后应用中需通过调整用药剂量、筛选赋形剂等途径减轻其副作用,需进一步探讨方法的治疗机理,为更有效治疗猪高热综合征做深入研究。     

熵权分析法在地下储气库设计中的应用

针对地下储气库设计方案优选涉及因素较多的问题,提出基于层次分析法(AHP)和熵权法确定最佳设计方案。采用层次分析法和信息熵方法相结合的组合赋权法确定垫层气量、注气结束时的最大地层压力、注采井数、压气站功率、工程投资和使用寿命等6个评价指标的综合权重,结合层次分析法对各个设计方案与理想解逼近程度的计算,实现方案优劣排序。实例计算结果表明:两种方法结合使用能够同时兼顾主观因素和客观因素的影响,为设计者选择技术上可行、经济上合理的设计方案提供了有效方法,并为优化地下储气库生产运行参数提供辅助决策。     

磷对旱地胡麻氮吸收转运及利用的影响

为研究磷对旱地胡麻氮吸收转运及利用的影响,以胡麻品种‘轮选2号’和‘定亚22号’为材料,4个施磷(P₂O₅)水平(0、45、90、135 kg/hm²)为因素,采用完全随机区组设计,于2017年和2018年在定西进行大田试验。结果表明：磷影响旱地胡麻地上部分氮吸收转运和氮生理利用率,且年份间差异显著;年份、品种和磷互作对花期和成熟期地上部分氮吸收量、成熟期籽粒氮吸收量和分配率,茎叶和其他部分中氮总转运量、转运率、贡献率及氮生理利用率影响显著。与不施磷相比,施磷使旱地胡麻花期和成熟期地上部分氮吸收量平均提高76%和82%;成熟期籽粒中氮吸收量和分配率平均提高127%和25%;茎、叶和其他部分中氮的转运量和转运率分别平均提高556%、102%、237%和16%。‘轮选2号’氮生理利用率随施磷量增加而显著增加,‘定亚22号’氮生理利用率在施磷(P₂O₅)90 kg/hm²和135 kg/hm²间差异不显著。相关分析表明,施磷量与旱地胡麻氮吸收转运和利用显著正相关。     

沙棘象生物学特性及防治的研究

经过几年的调查,我们发现沙棘象对沙棘种实的危害相当严重。1987年延安南泥湾林场沙棘的种实因该虫为害颗粒无收,在榆林、铜川也有类似情况。为此,1987-1989年我们在陇县关山对其生物学进行了研究。一、分布、形态特征及为容(图1) 沙棘象(Curculio hippophes Zhang)分布于陕西省的陕北、渭北和关山等地区,沙棘种子被害率达20-80％。成虫除产卵时在果实上留有产卵孔外,还啃食果皮作为补充营养,使果实失去利用价值。幼虫蛀食种仁并引起大量落果。     

林业的契约性

林业的本质就是人力资本同森林资源的契约。理解林业契约性对于协调人与人之间的关系,协调人与物的关系十分重要。宏观层面的林业契约要尊重自然,反哺于自然,在人类文明与自然演化相互作用中寻找一个最佳结合点;微观层面的林业契约要尊重人力资本的特殊性,产权清晰,激励有效,建立以市场为基础的林业组织形式。     

Effects of soil temperature and elevated atmospheric CO2 concentration on gas exchange, in vivo carboxylation and chlorophyll fluorescence in jack pine and white birch seedlings

One-year-old jack pine (Pinus banksiana Lamb.) and current-year white birch (Betula papyrifera Marsh.) seedlings were grown in ambient (360 ppm) or twice ambient (720 ppm) atmospheric CO2 concentration ([CO2]) and at three soil temperatures (Tsoil = 7, 17 and 27 degrees C initially, increased to 10, 20 and 30 degrees C two months later, respectively) in a greenhouse for 4 months. In situ foliar gas exchange, in vivo carboxylation characteristics and chlorophyll fluorescence were measured after 2.5 and 4 months of treatment. Low Tsoil suppressed net photosynthetic rate (Pn), stomatal conductance (g(s)) and transpiration rate (E) in jack pine in both CO2 treatments and g(s) and E in white birch in ambient [CO2], but enhanced instantaneous water-use efficiency (IWUE) in both species after 2.5 months of treatment. Treatment effects on g(s) and E remained significant throughout the 4-month study. Low Tsoil reduced maximal carboxylation rate (Vcmax) and PAR-saturated electron transport rate (Jmax) in jack pine in elevated [CO2] after 2.5 months of treatment, but not after 4 months of treatment. Low Tsoil increased actual photochemical efficiency of photosystem II (PSII) in the light (DeltaF/Fm') in jack pine, but decreased DeltaF/Fm' in white birch after 4 months of treatment. In response to low Tsoil, photosynthetic linear electron transport to carboxylation (Jc) decreased in jack pine after 2.5 months and in white birch after 4 months of treatment. Low Tsoil increased the ratio of the photosynthetic linear electron transport to oxygenation (Jo) to the total photosynthetic linear electron transport rate through PSII (Jo/J(T)) in both species after 2.5 months of treatment, but the effects became statistically insignificant in white birch after 4 months of treatment. High Tsoil decreased foliar N concentration in white birch. Elevated [CO2] increased Pn, IWUE and Jc but decreased Jo/J(T) in both species at both measurement times except Jc in white birch after 2.5 months of treatment. Elevated [CO2] also decreased g(s) and E in white birch at high Tsoil, Vcmax in both species and triose phosphate utilization in white birch at low Tsoil after 4 months of treatment, and DeltaF/Fm' in white birch after 2.5 months of treatment. Elevated [CO2] also increased foliar N concentration in both species. Low Tsoil caused no permanent damage to PSII in either species, but jack pine responded and acclimated to low Tsoil more quickly than white birch. Photosynthetic down-regulation and a decrease in photosynthetic electron transport to photorespiration occurred in both species in response to elevated [CO2].     

Effects of soil temperature on parameters of a coupled photosynthesis-stomatal conductance model

To examine the effects of soil temperature on a coupled photosynthesis-stomatal conductance model, seedlings of trembling aspen (Populus tremuloides Michx.), jack pine (Pinus banksiana Lamb.), black spruce (Picea Mariana (Mill.) B.S.P.) and white spruce (Picea glauca (Moench) Voss) were exposed to soil temperatures ranging from 5 to 35 degrees C for 4 months. Light and CO(2) response curves of foliar gas exchange were measured for model parameterization. The effects of soil temperature on four key model parameters, V(cmax) (maximum rate of carboxylation), J(max) (maximum rate of electron transport), alpha (energy conversion efficiency or quantum efficiency of electron transport) and R(d) (daytime dark respiration), were modeled using two third-order polynomial equations and a modified Arrhenius equation. In all species, V(cmax) and J(max) increased with soil temperature up to an optimum, and then decreased with further increases in soil temperature. In the conifers, alpha showed a similar response to soil temperature as V(cmax) and J(max), but soil temperature had no significant effect on alpha in aspen. Soil temperature had no significant effect on R(d) in any species. The three equations described the relationships between soil temperature and the model parameters reasonably well, but performed best for V(cmax) and worst for alpha. No significant relationships were identified between soil temperature and the parameters of the stomatal conductance model.     

陕北黄土高原区日光温室蔬菜产业发展的几点思考

阐述了陕北黄土高原区日光温室蔬菜产业发展的优势和现状，通过深入到陕北蔬菜生产和销售的第一线就其日光温室蔬菜生产等方面的问题进行了调查研究，综合分析陕北黄土高原区日光温室蔬菜产业发展的制约因素。结果认为，主要存在着无公害蔬菜标准化生产和消费的社会意识和氛围不浓，产品质量和生产效益相对较低；蔬菜“优质优价”的市场机制还未建立，蔬菜质量监督检测机构尚未形成；日光温室蔬菜无公害标准化生产的推广服务体系尚未建立，产业化组织机制发育不健全；日光温室蔬菜生产规模小，品牌产品缺乏；农民文化水平偏低等五个方面的制约因素。并就陕北日光温室蔬菜产业可持续发展提出了相应的对策，包括充分发挥气候资源优势，合理规划设施布局；实施品牌战略，推行无公害生产；增强科技意识，提高市场竞争力；科学管理，提高生产水平；加强组织领导，走产业化之路等几个方面。     

烟蚜危害对烟草生理及生长发育的影响

１９８７￣１９９２年在网室内进行了烟蚜危害烟草的试验研究，结果表明：苗期开始受害的烟草，现蕾期叶片过氧化物同工酶活性加强，种类增多，随烟蚜侵害水平的提高，烟草叶片叶绿素含量下降，净光合强度减强，总氮和蔗糖含量升高，还原糖含量略有增加；株高降低，叶片数减少，现蕾期推迟８￣１５天。