侵蚀果园长期植草的生态效益分析   总被引：1，自引：0，他引：1  

罗旭辉  詹杰  王义祥  黄毅斌  黄秀声  王成己  翁伯琦 《草地学报》2011,19(5):729-734

针对山地果园不合理开发引发的土壤侵蚀和土壤退化问题,将适生牧草套种于幼龄侵蚀果园,开展水土流失、土壤肥力及果树生长的定位观测。结果表明:套种平托花生(Arachis pintoi)、圆叶决明(Chamaecrista rotundifolia)1～12年,年地面径流系数0～0.0136,均值为0.007左右,仅为清耕处理的1/10,基本无土壤侵蚀发生;套种11年,套种区0～30 cm土层的土壤pH值比清耕分别提高0.25～0.30个单位,0～15 cm土层土壤有机碳、碱解氮、有效磷质量分数比清耕提高7.595～6.728 g·kg^-1,26.84～31.89 mg·kg^-1,3.57～4.62 mg·kg^-1;轻组有机碳质量分数在0～30 cm土层呈套种平托花生>套种圆叶决明>清耕的变化趋势,重组有机碳质量分数在0～15cm土层亦呈相同变化趋势。套种处理有助改善果肉糖酸比和商品果率,牧草综合利用可明显提升果园建园初期的经济效益,尽管套种处理给果树带来一定的减产。  相似文献   

有机生产模式下牧草粘虫防治方法的初步研究   总被引：1，自引：0，他引：1  

宋高翔  杨胜林  王普昶 《草地学报》2011,19(5):880-883

为探索牧草有机生产模式下的粘虫(Mythimna separata Walker)防治,对有机牧草种植区和非有机牧草种植区的5种牧草,通过生物农药BT、农业防治即时刈割利用牧草和化学合成农药溴氰菊酯、辛硫磷处理,进行草地上的粘虫防治试验。结果表明:生物农药BT防效与常规农药校正防效无显著差异,校正防效达到91.67%～98.59%;其次为即时刈割利用牧草,校正防效达到52.78%～81.35%,该法与有机生产理念高度吻合,可作为有机牧草生产中首选的防治方法之一。  相似文献   

Photosynthetically active radiation use efficiency of <Emphasis Type="Italic">Dactylis glomerata</Emphasis> and <Emphasis Type="Italic">Schedonorus phoenix</Emphasis> along a hardwood tree-induced light gradient     

Charles M. Feldhake  D. P. Belesky 《Agroforestry Systems》2009,75(2):189-196

Photosynthetically active radiation use efficiency (PARUE) of orchardgrass (Dactylis glomerata L.) and tall fescue (Schedonorus phoenix (Scop.) Holub) was determined. Leaf mass was harvested for canopies at different shade levels when each reached 20 cm height with 5 cm residue for regrowth to simulate grazing. Total incident PAR at each site was summed for the growth period (S-PAR). Values for PARUE were calculated from dried leaf mass divided by S-PAR. The more highly shaded plants reached 20 cm at lower S-PAR. While overall leaf mass decreased linearly with shade induced decreases in S-PAR, PARUE increased exponentially. The coefficients for the equations representing this exponential increase vary for forage species and may represent a useful index for characterizing forage response to silvopastoral systems.  相似文献   

Temporal dynamics of forage succession for elk at two scales: Implications of forest management     

D.R. Visscher  E.H. Merrill 《Forest Ecology and Management》2009

Rapid conversion of lodgepole pine (Pinus contorta) dominated landscapes in western Alberta to a mosaic of successional stand ages has long-term implications for elk populations in the region that have not been fully assessed. We developed stand-level models of forage succession using data from 159 cutblocks to simulate forage and cover availability within the home range of an elk under “even-flow” and “pulsed” timber cutting scenarios that are common in this area. We found forage biomass peaked approximately 9 years following felling for both herbaceous (graminoids and forbs) and palatable browse forage. Forage production was determined primarily by the age of the cutblock (time since felling) and to a lesser extent elevation, compound topographic index (a measure of site wetness), and the distance to the nearest deciduous forest patch. Forbs became increasingly abundant as stands matured. Browse composition shifted from palatable species to unpalatable species after approximately 30 years. Within an elk home range (100 km²), we found that simulating an “even-flow” cutting regime resulted in forage availability that was always higher than under the current conditions of 90% forests when more than 10 ha were harvested per year. Further, forest cover (>30$>30$-year-old stands) was never less than the guideline of 60% of the area needed to provide adequate thermal and hiding cover. In contrast, when a “pulsed” harvest scenario was simulated, similar to what occurs for mountain pine beetle control, forage availability changed dramatically over time as a large cohort of harvested timber aged. Without further harvesting the stand conditions in the home range eventually returned to a state of pre-harvest risk for mountain pine beetle outbreak. We demonstrated several additional harvesting scenarios that avoided the potential risk and produced a much higher level of forage than currently exists.  相似文献   

Trophic consequences of postfire logging in a wolf–ungulate system     

M. Hebblewhite  R.H. Munro  E.H. Merrill 《Forest Ecology and Management》2009

Controversy surrounds postfire logging, often because of negative effects on snag-dependent wildlife species. Few studies, however, have examined effects on early-seral species that may benefit from postfire logging, nor effects on trophic relationships. We studied the effects of postfire logging on trophic dynamics between wolves (Canis lupus), three ungulate species and ungulate forage biomass during the first 3 years in a large burn in the Canadian Rockies, Alberta, Canada. We examined plant biomass and ungulate responses to two treatments (post- and prefire logging) compared to a burned but unlogged area (control). We evaluated resource selection for the three treatments by elk (Cervus elaphus) using radiotelemetry and for deer (Odocoileus spp.), moose (Alces alces), and, secondarily, elk using pellet counts. Elk resource selection was modeled as a function of the trade-off between wolf predation risk and herbaceous forage biomass to test for trophic impacts of postfire treatments. Postfire logging had transient effects on total herbaceous biomass; while forb biomass was reduced, increases in graminoid biomass more than compensated by the third year. Prefire logging areas were dominated by a few species, but had generally higher forage biomass by the third year. Ungulates avoided postfire and prefire logged areas despite greater herbaceous biomass. Only when we considered elk resource selection as a function of both forage and wolf predation risk was the extent to which trophic interactions affected by postfire logging revealed. Wolves selected proximity to roads and the higher forage biomass associated with postfire logging in open logged areas. This translated to the highest predation risk for elk in postfire logged areas. Thus, ungulates avoided postfire logged areas because of human alteration of top-down predation risk despite enhancements to bottom-up forage biomass. Managers should consider trophic consequences of postfire logging on the interactions among species when gauging logging effects on terrestrial ecosystems. Making use of existing roads, minimizing the construction of new roads, and managing road removal following postfire logging will help mitigate the negative effects of postfire logging on terrestrial ecosystems.  相似文献   

CIMMYT牧草DNA导入普通玉米后植物学形态变异研究     

张兴端  霍仕平  向振凡  张健  晏庆九  余志江  张芳魁  何平  秦世明 《中国农学通报》2009,25(16):8-12

本研究以CIMMYT牧草和4个普通玉米自交系为遗传交配材料,比较研究了CIMMYT牧草和4个杂交（回交）后代的植物学形态特征及其与普通玉米的差异。结果表明,CIMMYT牧草能将其生长繁茂、分蘖力强、生物产量高的特性遗传给杂交后代,并有较强的世代传递能力;该牧草幼苗、植株及其生长习性、花器官、种子特征等与普通玉米差异明显,其与普通玉米的杂交后代基本保持了它的生长发育特性,但花器官和种子特征更偏向于普通玉米;回交后代除保持了一定的分蘖特性、明显的多穗和返祖现象外,其余特征特性与普通玉米基本没有区别。  相似文献   

甜高粱饲用品质性状与形态性状的相关分析   总被引：6，自引：0，他引：6  

罗峰  孙守钧  裴忠有  高建明  李子芳 《华北农学报》2009,24(6)

以相关分析法研究了28个甜高粱品种饲用品质性状与形态性状的相关关系.相关分析和通径分析表明:株高和鲜质量对饲用品质性状的直接作用最大,其次是分蘖数和茎粗,节数的直接作用最小.饲用品质性状间也存在相关关系:锤度与粗纤维呈显著正相关,相关系数为0.411 9,与粗蛋白和蜡粉呈显著负相关,相关系数分别为-0.547 5和-0.632 2;粗蛋白与粗纤维呈极显著负相关,相关系数为-0.883 7.因此,在甜高粱品种选育过程中,应充分考虑这些饲用品质性状间的制约关系.  相似文献   

威宁芜菁甘蓝栽培利用技术要点   总被引：4，自引：0，他引：4  

熊先勤  李富祥 《农技服务》2009,26(8):32-32,74

对威宁芜菁甘蓝的特征特性和栽培利用技术进行了介绍,以加快在生产上对其推广应用,充分发挥其品种生产潜力和优势,促进贵州草地生态畜牧业冬春季节饲草料短缺问题的解决,支撑贵州草地生态畜牧业的健康发展,保障农民增收。  相似文献   

饲用高粱品种品质性状的比较及评价     

崔凤娟  田福东  王振国  李岩  徐庆全  呼瑞梅  李默  邓志兰  周福荣 《草地学报》2012,20(6):1112-1116

为筛选出适宜通辽地区种植的饲用高粱(Sorghum bicolor)品种,2011 年对8个饲用高粱品种进行了田间比较试验,系统测定并分析了与动物生产性能相关的粗蛋白、中性洗涤纤维、酸性洗涤纤维的含量,及鲜草产量、干草产量、干鲜比。结果表明:大力士和甜格雷兹品质性状均优于其他6个品种,且品种间差异均达到极显著水平(P<0.01),通甜1号草产量最高,而品质略低于大力士和甜格雷兹,因此大力士、甜格雷兹适合作青饲利用,通甜1号适合作青贮利用,这3个品种在通辽地区均具有推广价值。  相似文献   

施肥和播种量对扬州地区苜蓿生长特性和产草量的影响     

潘玲  魏臻武  武自念  张栋  郑曦  陈斐  刘倩  李伟民 《草地学报》2012,20(6):1099-1104

用裂区试验设计研究扬州地区苜蓿(Medicago sativa)不同播种量和施肥水平对产草量及生产性能的影响。结果表明:江淮地区苜蓿推荐播种量为18.75 kg·hm^-2,氮、磷、钾推荐施用量分别为23,113,68 kg·hm^-2时,此时苜蓿的理论产草量可达22858.25 kg·hm^-2。单独施用氮、磷、钾肥时,在一定范围内对苜蓿产草量有促进作用,但当超过最大施用量时,对苜蓿的生长反而造成抑制。建议氮肥施用量不超过30 kg·hm^-2,磷肥施用量不超过130 kg·hm^-2。氮、磷、钾共同施用时苜蓿产草量才能达到最大值;氮肥在苗期、分枝期和初花期对苜蓿植株生长均有一定的促进作用;磷肥促进苜蓿主枝数的增加,氮钾肥有利于苜蓿侧枝数的生长。  相似文献