转基因生物对生物多样性的影响

随着转基因生物，尤其是转基因作物的不断推广，转基因生物对生物多样性的影响受到越采越多的关注。其中包括转基因作物潜在的侵袭力、基因漂移、对生物多样性的冲击以及对农业生产的影响等。本文重点论述了近年来转基因植物对农业生态系统生物多样性影响的研究进展，包括转基因植物对遗传多样性的影响。     

农事活动对茶园生物多样性的影响

农事活动如土地利用、耕作、套作、采茶与修剪、施肥、农药、生物防治技术、品种改良等是茶园生产力提高的重要途径，同时也是影响茶园生物多样性的重要因素之一。本文论述农事活动对茶园生物多样性影响以及生物多样性保护对提高茶园生产力作用，启示人们采取合理的农事活动方式，合理管理有害生物，减少农事活动对茶园生物多样性的负面影响。     

园林植物的生物多样性与景观设计的关联性

本研究旨在探讨园林植物的生物多样性与景观设计之间的关联性,并分析其在实践中的重要性和应用价值。园林植物的生物多样性对景观美学、生态功能和可持续发展具有重要影响。通过文献综述和案例研究,本研究系统地分析了生物多样性对景观设计的影响和植物选择、配置、管理等方面的应用策略。研究发现,生物多样性丰富的植物群落可以提升园林景观的观赏价值,增加景观的层次感和丰富度。同时,园林植物的生物多样性也为生态系统提供了重要的服务功能,如水循环调节、空气净化和土壤保持等。因此,保护和增加园林植物的生物多样性对于实现园林景观的可持续发展至关重要。研究结果为园林景观设计和实践提供了有益的指导和借鉴。     

氮营养管理对液体种植马铃薯生物产量分配和氮利用效率指数的影响

国家航空和宇宙管理局开展了一项控制环境条件下利用循环营养薄膜技术——液体系统生产马铃薯的试验，它是人类在长时间宇宙飞行中生存的支撑条件之一。标准营养液管理方法包括用硝酸调节稳定DH值和相当于改良荷格兰德溶液强度一半的电传导率的日调整，其中，硝酸盐是唯一的氮源。虽然这     

城市化对乡土园林植物资源多样性的影响

随着城市化的快速推进,乡土园林植物资源面临前所未有的挑战。海南岛作为一个研究的案例,凸显了这一问题的严重性。曾经盛行于海南的标志性植物椰子树、独特的槟榔园和广泛分布的竹林丛,在城市化的浪潮中面临着消失的危险。海南岛的这些乡土园林植物不仅具有高度的生态价值,还深深扎根于当地的文化和传统中。为了城市的发展,大量的乡土植物被砍伐或替代,导致生物多样性的丧失和生态平衡的破坏。本研究强调了在城市化进程中,对乡土园林植物资源的保护与合理利用的重要性,为未来的城市规划与生态保护提供了宝贵的参考。     

生物炭和氮肥施用量对番茄生长和 水氮利用效率的影响

为探究施用生物炭能否缓解因过量施氮对番茄生长可能造成的负面影响,进行了二因素(氮肥和生物炭)三水平完全随机区组盆栽试验。3个施氮量分别为100,200,400 mg/kg,3个施碳量分别为0,2.5,5.0 g/kg。通过对番茄茎、叶和果实干鲜质量、累积灌溉量、水氮利用效率的测定和分析,获得如下主要结果:与中低施氮量相比,高施氮量处理番茄茎叶干质量和累积灌溉量均显著降低,氮肥利用效率随施氮量的增加而显著降低;与不添加生物炭处理相比,添加生物炭显著提高了番茄叶和果实干质量、累积灌溉量和水氮利用效率。因此,适量施用生物炭,可有效减缓高氮对番茄生长的抑制作用。     

棉秆和生物炭还田对棉田土壤理化性质及棉花水氮利用率的影响

通过探究棉秆及其生物炭还田对棉田土壤理化性质、硝态氮淋洗及水氮利用率的影响,为干旱区农业资源的合理利用及土壤地力提升提供理论依据。本研究在前期已连续开展了2年(2019—2020年)棉秆及其生物炭还田的基础上进行,试验设置4个处理：不施氮(N0)、施氮(N360)、施氮+秸秆(N360ST)和施氮+生物炭(N360BC);其中氮肥用量为360 kg/hm²,棉花秸秆用量为6 t/hm²,生物炭用量为3.7 t/hm²(与棉花秸秆等炭量)。结果表明：与N0处理相比,N360、N360ST和N360BC处理显著增加土壤孔隙度、全氮、硝态氮淋洗量、棉花株高、总生物量、氮素吸收、籽棉产量和灌溉水利用率;显著降低土壤pH和水分淋洗量。与N360处理相比,N360ST和N360BC处理显著增加土壤总碳、速效钾、速效磷和碳氮比的含量,N360ST处理土壤水分淋洗量和硝态氮淋洗量分别较N360处理增加33.00%和40.16%,而N360BC的硝态氮淋洗量较N360处理降低40.06%。与N360处理相比,N360ST和N360BC处理...     

生物有机肥对苹果幼苗生长、生理特性以及土壤微生物功能多样性的影响

为明确生物有机肥不同施入量对苹果幼苗长势及根际土壤微生物功能多样性的影响,以1年生'烟富8号'苹果幼苗为试验材料,采用盆栽试验,设置4个处理,即鸡粪CK[35 g/(kg·土)]、生物有机肥T1[23.3 g/(kg·土)]、T2[35 g/(kg·土)]及T3 [70 g/(kg·土)].结果 表明,生物有机肥增加苹...     

茶园间作增进生物多样性和提升茶叶品质的研究进展

生物多样性越来越成为全世界关注的热点和难点问题,因为它直接关系到人类的生存环境和生墒质量。茶园的合理间作不但有利于增进茶园系统中生物多样性,也有利于茶叶品质的提高,这为茶叶生产提供了科学的方法和理论依据。     

Nitrogen Fertilization on Rye Pasture: Effect on Forage Chemical Composition, Voluntary Intake, Digestibility and Rumen Degradation

The effects of nitrogen (N) fertilization of a rye pasture (Secale cereale L.) on the chemical composition of forage and its utilization in vivo and in situ were investigated in winter (W) and early spring (S). Half of the paddock to be assayed was spread with 93 kg urea–N ha^?1 (treatment F), and the other half was not fertilized (treatment NF). Each experiment lasted for 17 days; apparent dry matter digestibility in vivo, voluntary dry matter intake (DMI) and digestible DMI were measured on nine rams per treatment. Two rumen cannulated animals per treatment were under the same feeding regime, and used to collect samples of rumen contents. The concentrations of ammonia (NH₃) and short‐chain fatty acids and pH were measured in these samples. The offered forage was also incubated in the rumen of three Holstein–Friesian steers to estimate its degradation parameters in situ. Fertilization with N increased total N and decreased dry matter (DM) and non‐structural carbohydrate concentrations in both periods. DMI was reduced by fertilization. The rumen concentrations of NH₃ were higher in F than in NF in both periods. In both periods, the effective DM degradability of forage was higher in F than in NF. N fertilization affects chemical composition, voluntary intake and rumen digestion of forage from rye pasture.     

Effect of Gibberellic Acid Spray and Basal Nitrogen and Phosphorus on Productivity and Fatty Acid Composition of Rapeseed-Mustard

Two field experiments were conducted during] 994-95 to study the effect of spray of 10⁻⁵ M GA3 at 40 days after sowing on mustard ( Brassica juncea (L.) Czern & Coss.) cv. Varuna grown with basally applied 0, 40, 80 and 120 kg N ha⁻¹ (Expt. 1) and 0,15, 30 and 45 kg P ha⁻¹ (Expt. 2) on pod number per plant, seeds per pod, 1000 seed weight, seed yield, biological yield, harvest index and fatty acid composition of oil. No significant difference between water and GA3 spray was found when basally applied nitrogen was 0 or 40 kg N ha⁻¹. N₈₀ proved to be the best for yield characteristics. In another experiment on phosphorus, GA₃ and 30 kg P ha⁻¹ individually enhanced the yield, but interaction of GA₃ and P remained non-significant. The fatty acid composition of oil in both experiments was significantly affected only by nitrogen and phosphorus treatments for oleic acid and erucic acid. It was found that return in the form of yield was more for every kg applied fertilizer under GA, spray treatment. The response was more for N fertilizer in comparison to P. GA₃ at a low level of fertilization significantly increased the return from fertilization.     

基于高通量测序的土壤细菌组成、丰度及多样性分析

研究盐碱地土壤微生物群落结构变化,细菌数量变化可以作为高粱耐盐材料筛选的标准之一,本研究将为高粱耐盐材料的选育及高粱耐盐性研究提供理论依据.试验采用Illumina Miseq高通量测序方法对盐碱地高粱根际菌群结构进行分析,选用10份不同的高粱亲本材料,采集盐碱地高粱根际土壤样品,研究结果表明:耐盐材料OTU数量较多,...     

不同有机物料对土壤基本化学性质及可溶性有机碳氮的影响

通过研究不同有机物料替代对河南潮土化学性质及可溶性有机碳/氮(DOC/N)分布的影响,探讨潮土适宜有机物料替代比例。结果表明:不同有机物料替代较对照明显提高了土壤基本养分的含量。其中,秸秆替代化肥40%处理土壤有机质和土壤碱解氮的含量提高最明显分别达到13.4 g/kg、93.99 mg/kg;牛粪秸秆共同替代化肥30%~40%显著提升了土壤全氮、速效磷、速效钾含量,分别达到0.90 g/kg、2.94 mg/kg、224.97 mg/kg。秸秆单独替代较牛粪秸秆共同替代对土壤DOC提升效果好,其中秸秆替代化肥40%处理DOC含量最高达到15.45 mg/kg;而牛粪秸秆共同替代则提高了DON,其中牛粪秸秆共同替代化肥30%处理的DON含量最大,为12.88 mg/kg。牛粪秸秆共同替代化肥30%处理的可溶性有机质的SUVA254 nm最高[16.24 L/(g·cm)],说明此处理有利于富含芳香环结构的有机质物质的积累。综上所述,其中秸秆替代40%和秸秆牛粪共同替代30%~40%对土壤基本肥力提升相对更明显。     

Chemical Composition and In Vitro Dry Matter and Organic Matter Digestibility of Triticale Forage

Triticale (X Triticosecale Wittmack) cultivars Council and Morrison were planted in mid-September (early planting) and mid-October (late planting) in 1984 at the Alabama A &: M University-experiment station for studying organic matter digestibility. The plants were harvested at the tillering, milk and dough stages and samples were subjected to proximate analyses and in vitro digestibility tests. A 1,100 lb Hereford steer fitted with a permanent ruminal fistula was used as the rumen fluid donor. In vitro dry matter digestibility (IVDMD) and in vitro organic matter digestibility (IVOMD) were determined by Moore's modification of the two-stage digestion technique of T illy and T erry (1963). Triticale cultivar Council was comparable to Morrison for phosphorus (P), dry matter (DM), ceil wall content, IVDMD and IVOMD. Crude protein (CP) and ash content were significantly higher for Morrison than for Council , while gross energy (GE) was significantly higher for Council than for Morrison. Both early and late plantings showed similar levels of DM, GE, P and cell wall constituents. However, CP and ash content were higher for early planting than late planting. The tillering stage was consistently higher than the milk or dough stages for CP, ash, P, calcium (Ca), IVDMD and IVOMD. The results indicate that the milk stage was superior to the tillering or dough stages in DM and cell wall content. Results from this study showed no significant differences in digestibilities for two triticale cultivars and planting dates. Based on the higher DM content at the milk stage, it seems that milk stage in triticale would be more acceptable as a forage than the tillering or dough stage.     

漳州市果园剖面土壤氮磷有效性研究

为了果园能更加合理的施肥,采用田间调查与室内分析相结合的办法,对漳州地区主要水果品种的果园剖面土壤营养及其结构进行研究。结果表明：各剖面土壤有机质含量的层次性十分明显,都大于对照相同层次土壤有机质含量。不同种类果园剖面不同层次土壤,其有机质差异很大。表层(0~20 cm)和亚表层(20~40 cm),基本表现为龙眼、荔枝园土壤有机质普遍处于比较低水平,而柚园、香蕉园、芦柑、枇杷园土壤有机质水平,处于较高水平。果园土壤可溶磷含量层次性很明显,表现出随着土壤剖面层次的加深而下降,除荔枝园和种质资源圃外,其他果园表层及亚表层土壤可溶磷含量都较高。龙眼园、荔枝园土壤有效磷含量处于低水平,而柚园、香蕉园、芦柑园、枇杷园土壤有效磷含量处于高水平。通过土壤管理或施肥,提高果园土壤碱解氮水平,大部分果园都处于极高状态或高水平;果园剖面各层次土壤N/P值明显低于对照剖面土壤,0.08~0.28倍于对照剖面土壤N/P值。不同剖面,其表层、亚表层土壤N/P值普遍小于中下层土壤。通过耕作、施肥等管理,降低了土壤N/P值。     

不同类型水稻土氮素组成及含量分布特征

研究川中丘陵地区不同类型水稻土氮素组成及含量分布特征,探讨土壤氮素与有机质含量间的相关关系。结果表明,研究区土壤氮素含量总体水平较低,全氮、碱解氮含量分别为（1.08±0.26）g/kg、（33.06±8.07）mg/kg,氨基酸态氮、氨态氮、氨基糖态氮的含量分别为（30.39±15.08）mg/kg、（96.06±13.01）mg/kg、（16.77±11.30）mg/kg;不同类型水稻土全氮、碱解氮与有机氮含量分布特征均为潜育型>渗育型>淹育型;不同类型水稻土中有机氮组分变化为氨态氮>氨基酸态氮>氨基糖态氮;不同类型水稻土全氮与有机质含量存在极显著正相关关系(P<0.01)。     

施氮量对糯玉米产量及土壤氮动态的影响

研究了不同氮肥用量对糯玉米产量、氮肥利用率、铵态氮和硝态氮累积及其土壤剖面分布的影响。结果表明:适量施氮可提高作物产量,过量施氮未表现出增产效果,氮肥利用率降低,糯玉米的氮肥效应方程:Y=13189+28.50X-0.11X2。施氮量可显著影响土壤中硝态氮的累积和分布,但对铵态氮的影响较小。当施氮(N)量达到270kg/hm2水平时,土壤硝态氮累积量远高于其他施氮水平,增加了土壤硝态氮的残留,同时,因降雨或灌溉的作用而向下层土壤移动,造成硝态氮的淋失,对环境造成潜在威胁。     

放牧对土壤理化性状及植被多样性的影响

放牧是家畜饲养方式之一,是草地最简单而又有效的利用方式,但放牧中的家畜家禽通过采食牧草、践踏土壤和牧草以及粪便排泄影响着草地植被和土壤,不同强度的放牧对地下土壤与地上植被的影响不同。本研究综述了近几年来放牧对地下部土壤有机质、氮、磷、钾、土壤容重、有机碳以及微生物多样性的影响,对植被多样性及草群成分的影响等,旨在为今后家畜放牧行为研究以及放牧科学研究提供理论依据。     

NyPa牧草对滨海盐碱地土壤改良效应研究

筛选适宜黄河三角洲滨海盐碱地栽植的高效生态、经济植物并确立其合理建植年限,为盐碱地生物治理提供科技支撑和理论依据.在东营市河口区黄河三角洲军马场基地的重度盐碱荒地上栽植NyPa牧草,并以盐碱荒地为对照,探讨不同年限的土壤改良效应.结果表明:(1)建植3、6、9年的NyPa牧草地与同期的荒草地相比,土壤的理化性能得到极大...