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1.
以2015年库尔勒市森林资源二类调查数据,提取的库尔勒分布面积最大的库尔勒香梨经济林生态系统为研究对象,采用平均生物量法测算了库尔勒香梨的生物量和碳储量,研究了库尔勒香梨经济林种植对当地碳储量的影响,以期对新疆人工林森林碳储量进行分析。结果表明:库尔勒市经济林生态系统碳密度不高,固碳潜力大。2015年库尔勒香梨生物量和碳储量分别为53.94万t和26.97万t,库尔勒香梨碳储量占经济林总碳储量的92.25%;在空间分布上,阿瓦提乡的库尔勒香梨经济林生物量和碳储量最高,分别为11.88万t和5.94万t,经济牧场库尔勒香梨经济林生物量和碳储量最低,分别为0.04万t和0.02万t。 相似文献
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我国柑橘产量已达2000×104t以上。浙江省柑橘面积12×104hm(2180万亩)左右,常年产量约200×104t,主要分布在衢州、台州、宁波、丽水、金华、杭州、温州等地;主栽品种为椪柑、温州蜜柑等?改甑南坌?势表明,随着人们生活水平的提高和柑橘产 相似文献
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通过调查重庆市柑橘产业情况,以生物量回归模型及碳密度分配状况为基础,探讨重庆柑橘林生态系统碳储量的动态变化。结果表明,重庆柑橘林生态系统碳储量随时间的变化规律与重庆柑橘种植面积、产量随时间的变化规律相似;直辖初至2000年果树碳储量、土壤碳储量和总碳储量增幅较小,2000年至2010年增幅较大,为118.4%。重庆柑橘林生态系统碳储量主要集中在10个柑橘生产重点区县,总碳储量为27.348×10^6t,占全市柑橘林总碳储量的88.94%,在全市森林生态系统碳储量中占有重要的地位（占7.23%）;在空间分布上呈现由渝西向渝东北递增的规律。 相似文献
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位于浙江省西南部的丽水是国家级生态示范区,可利用的野生植物有600多种,森林覆盖率达79.1%。丽水市有农村人口212.2万人,占丽水市总人口的84.3%,是名符其实的农业大市。2005年,全市粮食作物栽培面积11.3×104hm2,产量54.9×104t,水果栽培面积3.42×lO4hm2,产量32.36×104t,蔬菜栽培面积5.19×104hm2,产量124.13×104t,袋栽香菇5.1亿袋,产量3.14×104t。全市常年食用菌产量占全国总量的45％左右,为全国最大的食用菌产区,食用菌总产值占全市农业总产值的l/3。 相似文献
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正怀来县果树栽培历史悠久,是有名的林果大县,2000年被国家林业局命名为"全国名特优经济林葡萄之乡",2001年被国家林业局命名为"全国经济林建设先进单位"。2011年全县果树总面积3.8万hm2,果品总产量达到22.5万t。近年来,为适应日趋激烈的市场竞争,在林果产业化发展进程中,牢固树立品牌意识,在强化完善市场体系建设的同时,进一步加大林果专业合作社建设步伐,涌现出很多如"小北川红国光苹果专 相似文献
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辽西地区设施温室果树经济林栽培方兴未艾,但是果树经济林的系统性栽培技术尚未全面推广和应用,是导致经济效益不佳的瓶颈。文章总结辽西地区果树经济林密植高效栽培的优势及关键技术,以期为生产中提供借鉴。 相似文献
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针对经济林果树有机栽培的意义进行简单分析,经济林的种植为时代发展的必然趋势,对现代林业经济的发展,居民生活质量的提升也能够产生重要影响。经济林果树有机栽培期间土壤管理关键技术的应用,能够提升经济林果树有机栽培的整体效果,发挥技术应用的作用价值。 相似文献
10.
北方是我国果树种植的重要产地,因其气候原因,适宜更多果树生长。当然,北方气候对于果树经济林管理也带来了挑战,需要优化配套管理技术,才能保证生产出高产优质的水果,提升经济林生产效益。就北方果树经济林主要配套管理技术进行介绍,并探究提升北方果树经济林配套管理技术的有效途径和方法。 相似文献
11.
以"烟富3号"苹果园土壤为试材,采用人工播种生草栽培方法,研究多年生人工种植草类对黄淮地区苹果园常规养分和微生物数量的影响,以期为构建合理的土壤管理模式提供参考依据。结果表明:在蛇莓、匍枝委陵菜、五皮风、三叶草和黑麦草5种生草处理中,种植三叶草的园区土壤养分含量和微生物数量有最高值,其表层土壤有机质含量23.70 g·kg-1,全氮0.66 g·kg-1,有效磷28.03 mg·kg-1,速效钾19.60 mg·kg-1;底层土壤有机质含量12.31 g·kg-1,全氮0.36 g·kg-1,有效磷4.76 mg·kg-1,速效钾104.05 mg·kg-1;表层土壤细菌数量10.75×106 cfu·g-1,真菌数量4.96×104 cfu·g-1,放线菌数量6.73×105 cfu·g-1。黄淮地区苹果园选择三叶草进行生草栽培更利于土壤的培肥和果树的生长。 相似文献
12.
Nian-Feng Wan Xiang-Yun Ji Lars Pødenphant Kiær Shuang-Shuang Liu Jian-Yu Deng Jie-Xian Jiang Bo Li 《Landscape Ecology》2018,33(5):799-809
Context
Enhancing ground cover vegetation is an important agricultural practice that regulates herbivore and predator insects in agricultural landscapes. However, the effects of ground cover on the spatial distributions of these organisms have scarcely been explored.Objectives
Our goal was to measure the effects of ground cover on the spatial aggregation and association of insect herbivores and predators, which might contribute to the control of herbivorous pests.Methods
We conducted our experiments in peach orchards at two sites in eastern China. The two sites have experimental units with ground cover treatments that created a heterogeneous landscape. We conducted a 2-year experiment to investigate the abundance and distribution of herbivores (leafhoppers) and predators (ladybirds), using geostatistics to analyze their spatial aggregation and association.Results
The abundance of predators increased and that of herbivores decreased in ground cover orchards compared to control orchards without ground cover. The proportion of spatial structure was greater than 0.75 for both herbivores and predators in the control orchards, indicating a lack of spatial aggregation, and less than 0.75 in peach orchards with ground cover, indicating spatial aggregation. The correlation of spatial aggregation between herbivores and predators was significantly positive in the ground cover treatment, indicating association of the two insect guilds. In control orchards, on the other hand, this was not significant.Conclusions
The presence of ground cover increased predator abundance, spatial aggregation of herbivores and predators as well as their spatial association, suggesting a mechanism for more efficient control of herbivorous pests in peach orchards.13.
《Scientia Horticulturae》2005,107(1):17-24
Agricultural practices can play an important role in atmospheric CO2 emission and fixation. In this study, we present results on carbon fluxes in the biomass of two typical Mediterranean orchards indicating that proper canopy management coupled with other agricultural techniques could increase the absorption of atmospheric CO2 and its storage. We also discuss the potential environmental contribution of the orchards to enhancement of both soil and air quality. Trials were carried out in southern Italy on olive (Olea europaea L.) and peach orchards (Prunus persica L.) at different age and plant densities. At the end of each vegetative season, values of fixed atmospheric CO2 were calculated by measuring dry matter accumulation and partitioning in the different plant organs. In the early years, sequestered CO2 was primarily distributed in the permanent structures and in the root system while in mature orchards the fixed CO2 was distributed in leaves, pruning materials and fruit. Significant differences in amounts of fixed CO2 were observed in peach orchards cultivated using different planting and training strategies. The results underline the importance of training system, plant density and cultivation techniques in the absorption of atmospheric CO2 and its storage as organic matter in the soil. 相似文献
14.
The influence of landscape on insect pest dynamics: a case study in southeastern France 总被引：1，自引：0，他引：1
Benoît Ricci Pierre Franck Jean-François Toubon Jean-Charles Bouvier Benoît Sauphanor Claire Lavigne 《Landscape Ecology》2009,24(3):337-349
Managing the spatial distribution of crop and non-crop habitats over landscapes could be used as a means to reduce insect
pest densities. In this study, we investigated whether or not landscape characteristics affected the number of codling moths
in commercial orchards. To do this, we collected overwintering larvae in 2006 and 2007 in 76 orchards over a 70 km2 area in
southeastern France. We analysed variations in the number of larvae using correlation tests and linear models. As independent
variables, we took both characteristics of focus orchards (pear vs. apple, organic vs. conventional orchards) and of their
surrounding landscape (orchard density and hedgerow network attributes) into account in buffers with widths varying from 50
to 500 m. Although the codling moth is specialised on orchards, the number of codling moths was lower in orchards within a
high orchard density area. There was some indication that this effect was mostly due to the density of conventional orchards
and thus to the intensity of insecticide treatments. Conversely, we found no particular effect of abandoned or organic orchards.
In 2006, the number of codling moths was also significantly lower in a focus orchard when the hedgerow network acted as a
protection against the prevailing wind. Finally, major effects of landscape variables on the number of codling moths were
observed for distances of less than 150 m from the focus orchards, suggesting that codling moth management should be organised
over areas of about 16 ha.
Electronic supplementary material The online version of this article (doi:) contains supplementary material, which is available to authorized users. 相似文献
15.
为了探究塞罕坝地区不同典型人工林的碳汇能力,对塞罕坝机械林场3种林分类型,华北落叶松人工林、云杉人工林、樟子松人工林的最大生物碳贮量进行比较。研究结果表明：在平均胸径相同的前提下,华北落叶松的单株生物量及碳贮量最大,其次为云杉林,最小为樟子松林。在胸径小于16 cm时,华北落叶松林总碳贮量最高,其次为云杉林,最低为樟子松林;当胸径在16～28 cm时,总碳贮量由高到低分别为云杉林、华北落叶松林和樟子松林;当平均胸径大于28 cm时,总碳贮量由高到低分别为云杉林、樟子松林和华北落叶松林。各树种碳在各个器官的分配也有明显不同,华北落叶松的叶片和主干中碳所占比例随胸径的增加逐渐减小,侧枝则相反;樟子松叶片及侧枝中碳所占比例则随胸径的增加呈逐渐下降趋势,主干则相反;云杉林叶片中碳所占比例则随胸径的增加呈明显的增加趋势,主干中碳所占比例相反,枝条中碳所占比例则相对稳定。不同人工林生物碳贮量的相对大小与林分的平均胸径有关。 相似文献
16.
为了研究马铃薯在相同种植密度下高产优质最佳的行株距,采用37 500和60 000株 ? hm-2两种密度,通过扩大行距缩小株距,分别设置4个和7个行株距比处理,研究其对马铃薯茎叶干物质积累、光分布、光合特性、叶绿素荧光特性、产量及块茎淀粉、蛋白质、维生素C、还原糖含量的影响。结果表明：行株距比在低密度下为1.5、高密度下为2.5时,可提高茎叶干物质量、叶面积指数、叶绿素含量、净光合速率（Pn）、蒸腾速率（Tr）、气孔导度（Gs）、最大光能转化效率（Fv/Fm）、实际光化学量子效率（PSⅡ）、光化学猝灭系数（qP）、鲜薯产量及其淀粉、维生素C、可溶性蛋白含量,而胞间CO2浓度（Ci）、非光化学猝灭系数（NPQ）和还原糖含量的变化规律与之相反。‘青薯9号’高产优质的行距/株距在37 500和60 000株 ? hm-2种植密度下,分别为63.3 cm /42.2 cm和64.6 cm /25.8 cm。 相似文献
17.
Botriosphaeria dothidea分生孢子在苹果表皮和非生物表面的吸附作用(英文) 总被引：1，自引：0，他引：1
通过对Botriosphaeria dothidea分生孢子在6种非生物表面及苹果果面上的吸附作用的研究,发现在各种非生物表面上分生孢子表现出不同的吸附特性。封口石蜡膜、载玻片和凡士林包衣载玻片易于吸附孢子,其中石蜡膜最易被孢子吸附,而聚丙烯带和石蜡包衣载玻片不易被孢子吸附。在石蜡膜上滴加孢子后20 min即可达最大吸附,而在载物玻片,塑料膜,石蜡包衣载物玻片,凡士林包衣载物玻片和聚丙烯膜上需40～60 min才能达到最大吸附。在果实皮孔处,孢子吸附随孢子浓度及吸附时间增加而增加。孢子浓度在2．0×104-5．0×104／mL范围内,孢子在皮孔处的吸附数量无显著差异。但是在非皮孔处,孢子浓度至少需4×104／mL而且需吸附20～30 min后才能达到最大吸附。伴刀豆蛋白A(Conncavaline A)是孢子吸附的一种高效抑制剂,甚至在100μg/mL的浓度即足以抑制孢子吸附。 相似文献
18.
AIM: To investigate the hypothesis that low-molecular weight heparin (LMWH) regulates in vitro cytotrophoblast invasiveness and production of metalloproteinases-2 (MMP-2), tissue inhibitor of metalloproteinas-2 (TIMP-2). METHODS: Chorionic villi tissue of normal 6-8 weeks pregnancy was obtained. Trophoblastic cells were collected by trypsin-collagenase digestion and Percoll gradient centrifugation. The cytotrophoblastic cells were cultured for 24 h and divided into 4 groups according to the concentrations (1.0×102 IU/L, 1.0×103 IU/L or 1.0×104 IU/L) of LMWH adding into the medium. The contents of MMP-2 and TIMP-2 in cell culture supernatants were measured by the method of ELISA. Cytotrophoblast invasiveness was determined by Transwell chamber assay. RESULTS: With the increasing concentrations of LMWH, the invasion activity of cytotrophoblastic cells and MMP-2 secretion were increased. At concentration of 1.0×103IU/L, LMWH greatly enhanced cytotrophoblast invasiveness and the expression of MMP-2 (P<0.05). The levels of TIMP-2 were decreased after intervention with LMWH. At concentration of 1.0×103IU/L or 1.0×104 IU/L, LMWH induced a significant decrease in TIMP-2 expression. No significant difference between group 1×103IU/L and group 1.0×104 IU/L was observed (P>0.05). CONCLUSION: LMWH might regulate cytotrophoblast invasiveness in vitro by influencing the expression of MMP-2 and TIMP-2 in cytotrophoblastic cells. 相似文献
19.
The area of land occupied by exurban residential development is significant and has been increasing over the past several decades in the United States. Considerable attention has been drawn to the measurement of regional-scale patterns of land-cover change and assessment of its environmental and socioeconomic consequences. Yet little is known about the quantity of land-cover change within individual exurban residential parcels, which reflect homeowner preferences, land-management strategies, and the ecosystem services they generate. Similarly, little is known about the spatial autocorrelation of land cover among parcels and how it may change over time. Using a dataset delineating land-cover change within exurban residential parcels in southeastern Michigan from 1960 to 2000, the quantity and composition of land cover and carbon storage are examined. The spatial similarity of land-cover quantity among neighboring parcels is evaluated using local indicators of spatial association. Results show, among other findings, that (1) the number of exurban residential parcels, the quantity of tree cover, and amount of carbon storage increased steadily from 1960 to 2000; (2) the distribution of parcel sizes remained relatively constant and dominated by small parcels; (3) an increasing proportion of parcels were significantly similar to their neighbors; and (4) using a benefits transfer approach, new exurban parcels are estimated to store ~15,000–29,000 kg C over the study period. The measured changes in land cover and carbon storage improve our understanding of how ecosystem services may change in human-dominated landscapes and provide evidence that policy opportunities are available to increase carbon management. 相似文献