森林可持续经营环境友好型技术转让现状及建议

环境友好型技术转让作为实现全球可持续发展的重要手段之一, 在众多林业相关公约中均有谈及.文中介绍于目前与林业相关的技术转让渠道和现状, 分析技术转让中存在的障碍及改善措施, 讨论我国开展森林可持续经营技术转让的意义, 并对我国开展相关国际合作和进行政策规划提出具体建议.     

再生稻和双季稻田CH4排放对比研究

【目的】 为了探索生态可持续的稻作模式,对比研究了长江中下游地区双季稻和再生稻稻作模式的产量潜力和CH₄排放特征,以此为选取绿色、生态经济可持续的稻作模式提供科学依据。【方法】 于2017—2018年依托湖南省益阳市大通湖区宏硕生态农业农机合作社科研基地,设置了双季稻和再生稻2种模式,对比分析了产量潜力、稻田生育期间CH₄排放动态和稻田生态系统CH₄季节性累积排放规律以及评估了单位产量稻田CH₄排放。【结果】 试验期间,从产量方面来看,双季稻早稻产量为7.37 t·hm ^-2,再生稻头季产量为8.84 t·hm ^-2,头季相比早稻增产19.95%。双季稻晚稻产量为6.82 t·hm ^-2,再生稻再生季产量为3.39 t·hm ^-2,再生季相比晚稻减产50.29%。综合两季,双季稻总产量为14.19 t·hm ^-2,再生稻总产量为12.22 t·hm ^-2;从生育期间CH₄排放动态来看,双季稻在分蘖期和齐穗期左右排放较强峰值,再生稻除了在分蘖期和齐穗期有较强的排放以外,其在施用促芽肥时也出现了小峰值。但总体双季稻的排放范围（- 0.06—1.30 μmol·m ^-2·s ^-1）要高于再生稻的排放范围（- 0.01—0.70 μmol·m ^-2·s ^-1）;从稻田CH₄季节性累积排放来看,双季稻CH₄累积排放要高于再生稻。再生稻头季累积排放范围在23.90—266.59kg·hm ^-2,再生季累积排放范围在0.00—46.14 kg·hm ^-2。双季稻早稻季节累积排放范围在为35.57—251.29kg·hm ^-2,晚稻季节累积排放范围在为10.74—321.59 kg·hm ^-2。双季稻CH₄季节累积排放A-B（两叶一心至分蘖后期）段>B-C（分蘖后期至齐穗期）段>C-D（齐穗期至成熟期）段,且全生育期双季稻累积排放达922.35 kg·hm ^-2。再生稻CH₄累积排放B-C段>A-B段>C-D段,且全生育期CH₄累积排放为609.74 kg·hm ^-2,即相比对照双季稻,再生稻CH₄累积排放降低了33.89%;最后通过评估单位产量CH₄排放可知,早稻单位产量CH₄排放为0.069 kg·kg ^-1,头季单位产量CH₄排放为0.062 kg·kg ^-1,头季相比早稻减少了10.14%;晚稻单位产量CH₄排放为0.061 kg·kg ^-1,再生季单位产量CH₄排放为0.018 kg·kg ^-1,再生季相比晚稻降低了70.49%。综合两季,双季稻单位产量CH₄排放为0.065 kg·kg ^-1,再生稻单位产量CH₄排放为0.050 kg·kg ^-1,再生稻相比双季稻降低了23.08%。 【结论】 从单位产量下CH₄排放角度来看,在长江中下游双季稻的主产区扩大种植再生稻是为良策。     

Influence of suspended particulates on phosphorus loading exported from farm drainage during a storm event in the Everglades Agricultural Area

Purpose

The purpose of this study was to evaluate the influence of suspended particulates on P loading captured during a single storm event. The Everglades Agricultural Area of Florida comprises 280,000 ha of organic soil farmland artificially drained by ditches, canals, and pumps. Phosphorus (P)-enriched suspended particulates in canals are susceptible to transport and can contribute significantly to the overall P loads in drainage water.

Materials and methods

A settling tank experiment was conducted to capture suspended particulates during tropical storm Isaac in 2012 from three farms approximately 2.4 to 3.6 km² in size. Farm canal discharge water was collected in a series of two 200-L settling tanks over a 7-day drainage period, during tropical storm Isaac. Water from the settling tanks was siphoned through Imhoff settling cones, where the suspended particulates were allowed to settle and collected for P fractionation analyses, and compared to intact sediment cores collected from the canals.

Results and discussion

The discharged suspended particulates contained higher organic matter content, total P, and labile P fractions compared to the drainage canal sediments. Based on the equilibrium P concentrations, drainage canal sediments behave as a source of P to the water column. A 7-day continuous drainage event exported 4.7 to 11.1 t of suspended solids per farm, corresponding to 32 to 63 kg of particulate P being lost to downstream ecosystems. Drainage associated to this single 7-day storm event exported up to 61 % of the total annual farm P load.

Conclusions

It is evident from this study that short-term, high-intensity storm events can skew annual P loads due to the export of significantly higher suspended particulate matter from farm canals. Exported particulates rich in P, if captured and replenished back on farmlands, would be a sustainable farming practice that can provide a supplemental source of nutrients.

     

温度胁迫对褐飞虱不同抗性水平水稻 营养生长和生理指标的影响

[目的]研究温度胁迫对褐飞虱不同抗性水平水稻营养生长和生理指标的影响,为抗虫稻种的选育及合理布局提供参考.[方法]分别将处于四叶一心期和拔节期的抗虫稻ASD7、高感稻TN1和感虫稻桂育9号(GY9)置于人工气候箱中,设高温恒温、高温变温、异常低温和对照(CK)4个处理,连续处理5 d后测定水稻叶宽、株高、生物量、株水含率及叶片可溶性糖和可溶性蛋白含量.[结果]四叶一心期和拔节期,不同褐飞虱抗性水平水稻品种的叶宽均以异常低温处理最宽,高温恒温处理最窄;株高、株鲜重及水含率在高、低温胁迫下均较CK有不同程度的降低;水稻株干重、叶片可溶性糖及可溶性蛋白含量在异常低温处理下较CK升高,在高温变温处理下较CK降低.同一温度处理下,GY9的叶宽、株高和生物量最高,且其拔节期的水稻叶片可溶性糖和可溶性蛋白含量也相对较高.[结论]感虫稻GY9在不同温度胁迫下的生长发育较快、生理代谢物质含量较高,对温度胁迫的耐受力相对较强,能够适应广西初夏多变的气候.     

Identification and characterization of an anti-fibrotic benzopyran compound isolated from mangrove-derived Streptomyces xiamenensis

An anti-fibrotic compound produced by Streptomycesn xiamenensis, found in mangrove sediments, was investigated for possible therapeutic effects against fibrosis. The compound, N-[[3,4-dihydro-3S-hydroxy-2S-methyl-2-(4'R-methyl-3'S-pentenyl)-2H-1-benzopyran-6-yl]carbonyl]-threonine (1), was isolated from crude extracts and its structure, including the absolute configuration was determined by extensive spectroscopic data analyses, Mosher's method, Marfey's reagent and quantum mechanical calculations. In terms of biological effects, this compound inhibits the proliferation of human lung fibroblasts (WI26), blocks adhesion of human acute monocytic leukemia cells (THP-1) to a monolayer of WI26 cells, and reduces the contractile capacity of WI26 cells in three-dimensional free-floating collagen gels. Altogether, these data indicate that we have identified a bioactive alkaloid (1) with multiple inhibitory biological effects on lung excessive fibrotic characteristics, that are likely involved in fibrosis, suggesting that this molecule might indeed have therapeutic potential against fibrosis.     

沙棘微繁育苗产业化试验研究——水培沙棘茎段插穗不定根发生的机理

本文用水培方法研究了沙棘短茎段插穗生根的机理。结果表明,在用外源激素处理、控温控湿条件下,沙棘可以用极短的茎段(1～3芽段)插穗产生不定根,进而形成新的植物。沙棘插穗不定根形成有两种方式:一是茎段切面先产生愈伤组织,然后再分化为不定根;二是直接由茎皮层内分生组织产生不定根;且不定根产生具"茎多部位生根效应"。沙棘插穗不定根形成属于"温度敏感型",最适温度为16℃～26℃。外源激素对沙棘短茎段插穗生根表现出良好的诱导效应,而且对插穗苗的生长发育一定的影响,ABT优于GGR;"壮根素"效果优于生根粉,不仅促进发根,而且促进成熟不定根的早期结瘤。     

丁酸钠对鲫鱼生长和肠细胞增殖的影响

以初始体质量(6.02±0.16) g的鲫鱼(Carassius auratus)为研究对象, 在鲫鱼基础饲料中分别添加0.0 g/kg、1.0 g/kg、2.5 g/kg、5.0 g/kg、7.5 g/kg的包膜丁酸钠, 配制5种等氮等能的实验饲料, 研究不同浓度包膜丁酸钠通过促进鲫鱼肠细胞增殖对其生长作用的影响。实验在室内养殖系统中进行, 每水族缸饲喂30尾, 每处理组3个重复, 以鱼体质量3%~5%投喂量, 日投喂3次, 试验持续7周。实验结果表明: 在饲料中添加丁酸钠对鲫鱼有明显的促生长作用, 显著提高了鲫鱼前肠绒毛高度/隐窝深度的比值以及肠道细胞增殖因子CREB和CDX2基因的表达。当丁酸钠添加量为2.5 g/kg时, 鲫鱼增重率、特定生长率、蛋白质效率和肥满度最高, 显著高于对照组(P<0.05), 比对照组分别提高了25.76%、16.46%、28.91%和8.37%; 与对照组相比, 丁酸钠添加量达到2.5 g/kg时, 鲫鱼干物质与蛋白质表观消化率、前肠绒毛高度、肠道CREB基因和CDX2基因的相对表达量显著升高, 分别比对照组提高8.36%、6.21%、34.22%、51.11%和42.13%(P<0.05)。上述研究表明饲料中添加适量的丁酸钠可能通过显著提高鲫鱼肠绒毛高度和肠道细胞增殖因子CREB和CDX2基因的表达量, 从而促进其生长, 适宜添加量为2.5 g/kg。

     

基于图像处理的棉红枯病染病程度研究

为了有效地对棉红枯病的染病程度进行度量,首先运用综合阈值方法从背景图片中分割出叶面区域,根据棉红枯病的染病特点,在RGB颜色空间上提取叶面区域的红色和绿色分量;然后计算其平均值,将两个平均值相除得出红绿比。采用此方法分别对健壮叶面、染病叶面以及重染病叶面进行处理,得出各染病程度的红绿比取值范围并验证。研究表明,利用此方法进行染病程度的度量是可行的,为有目的地对棉花进行处理提供了理论依据。     

鸡蛋蛋壳裂纹敲击振动功率谱信号特征参数筛选和分析

运用自行研制的禽蛋裂纹检测装置,可以采集并分析敲击鸡蛋产生的响应信号,检测裂纹蛋。提取敲击响应信号功率谱的10个特征参数,并采用逐步回归法和遗传算法进行优化和筛选,以期选取更有效的特征参数,提高模型检测精度。结果表明,遗传算法筛选结果明显优于逐步回归法。当采用遗传算法筛选的4个特征参数(功率谱信号的第1共振峰对应的频率点、第1共振峰的功率谱与其前4个频率功率谱的方差、前3个共振峰功率谱方差、中低频段功率谱能量比)作为判别模型的输入向量,模型能取得最优结果,预测集判别率可达到97.2%。     

Quantifying morphological and genetic variation of sympatric populations to guide conservation of endangered,micro‐endemic springsnails

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