Improving the biodiversity benefits of hedgerows: How physical characteristics and the proximity of foraging habitat affect the use of linear features by bats

Within agricultural landscapes, linear features such as hedgerows and tree-lines provide valuable habitat for many species. We use data from 315 transects, completed as part of a national acoustic survey of bat distribution, to examine the incidence of four bat species adjacent to linear features in rural areas. The use of linear features was assessed in relation to hedgerow width, tree density, the presence of water and woodland proximity. To examine the effect of tree density, linear features were classified as either hedgerows without trees, hedgerows with sparse trees (comprising <50% tree canopy) or tree-lines (>50% tree canopy). The use of linear features by Pipistrellus pipstrellus was not affected by tree density; linear features of all types were associated with a similar increase in P. pipistrellus incidence. The use of linear features by Pipistrellus pygmaeus was dependent on both tree density and the proximity of woodland; only linear features containing trees provided an increase in P. pygmaeus incidence regardless of woodland proximity. P. pipistrellus and P. pygmaeus incidence was not affected by hedgerow width or the presence of water. Incidence of Nyctalus noctula and Eptesicus serotinus was unaffected by the density of linear features of any type. Many agri-environment schemes offer financial incentives for the creation and management of hedgerows. Optimising the biodiversity gain provided by linear features will maximise the effectiveness of these schemes. Agri-environment measures that encourage the provision and retention of hedgerow trees will benefit bats in agricultural landscapes.     

利用植物篱防治水土流失的技术及其效益研究综述

随着我国水土流失的日趋严重,植物篱技术已成为一项符合可持续发展原则的水土流失综合治理措施。概述了植物篱的定义、种类,篱笆植物的选择,植物篱的种植模式及其效益评价;根据目前研究状况,指出了当前评价指标体系的不足之处,并提出应建立综合评价指标体系,将所有指标划归为生态、经济、社会三大类;在评价时则要根据实际需要选取合适的指标,采用综合评价方法对植物篱的效益进行系统全面的评价。     

Growth of cassava cultivar TMS 30572 as affected by alley-cropping and mycorrhizal inoculation

The effect of inoculation with Glomus clarum, a vesicular-arbuscular mycorrhiza fungus, and alley-cropping on the growth of the cassava cultivar, TMS 30572, was investigated under field conditions in a low nutrient tropical soil. Cassava was grown either interplanted between two hedgerow tree species (alley-cropped) or sole-cropped. Sub-plots were either inoculated with G. clarum or were not inoculated. No effort was made to destroy the indigenous mycorrhizal fungi. Three months after planting, no significant influence of G. clarum inoculation was observed on the growth of roots, shoots or leaf area index (LAI). However, with time, inoculation and system of cropping enhanced these growth parameters. Nine months after planting, the total biomass of alley-cropped cassava was significantly higher than that of inoculated and non-inoculated sole-cropped cassava. Inoculation had led to an increase in the fresh tuber yield of both the alley- and sole-cropped cassava 12 months after planting. The LAI of both alley- and sole-cropped cassava inoculated with G. clarum increased. Received: 6 December 1996     

不同植物篱模式下土壤物理变化及其减流减沙效应研究

生物措施既能改善景观环境,又解决生态问题,是贵州缓解水土流失及农业非点源污染的重要措施.本文主要研究了植物篱模式与非植物篱模式下的土壤物理变化特征及减流减沙效果,分析了各物理量变化的水土保持机理.研究发现,供试的3种植物篱带均形成一定高度的土坎,有梯化坡地的效果,其微地貌变化大小顺序依次为:黄荆(Vitex neg undo)>新银合欢(L eucaw na leucocep hala)>马桑(Coriaria sinica):不同植物篱模式及不同取样位置的土壤样品体积质量(容重)、饱和导水率、雨水入渗速率及自然含水率均有较大差异,且各物理量之间有紧密关系;不同植物篱模式均有较明显的减流减沙效果,且植物篱对减少土壤侵蚀量的效果比减少径流更明显,其效果依次为免耕覆膜植物篱>植物篱>传统模式.     

不同植物篱对石灰性紫色土坡耕地土壤微生物学特性影响研究

以资阳市长期定位试验(10年)小区土壤为材料,研究了种植香根草植物篱、紫穗槐植物篱处理对紫色土坡耕地土壤微生物数量、微生物生物量碳(SMBC)和微生物生物量氮(SMBN)、土壤氨化强度、亚硝化作用和硝化作用强度、土壤脲酶和碱性磷酸酶活性的影响。结果表明,种植香根草和紫穗槐植物篱处理土壤细菌、放线菌、真菌数量分别比对照土壤增加了63.43%和36.63%,47.87%和71.89%,74.60%和43.65%;SMBC和SMBN分别增加了90.02%和83.32%,24.97%和45.04%;土壤脲酶活性和碱性磷酸酶活性分别增加了45.20%和61.86%,26.68%和38.95%;土壤氨化作用强度分别增加了73.28%和75.65%,而土壤硝化和亚硝化强度则分别降低了26.97%和52.96%,6.46%和22.19%。植物篱处理能够较好地改善土壤微生态环境,增加土壤中微生物数量、SMBC和SMBN,提高土壤氮素和磷素的利用效率。     

农业面源污染的植物篱控制技术研究进展

植物篱既是有效的水土保持措施,又是农业面源污染的源头控制技术之一。在介绍植物篱技术的概念、分类与设计的基础上．综述了植物篱控制农业面源效应的国内外研究进展,并对其在我国的研究应用进行了展望。     

水土保持措施对黑土流失区土壤理化性质的影响

针对黑龙江省东南部黑土区坡耕地所采取的4种水土保持措施的土壤进行了理化性质研究,分析了不同水土保持措施之间的差异.结果表明:0～50 cm黑土层有机质平均质量分数排序为植物篱＞谷坊＞退耕还林＞退耕还草,植物篱有机质质量分数115.66 g/kg,而退耕还草为69.43 g/kg;非毛管孔隙大小排序为植物篱(10.56％...     

短枝型苹果篱壁形整枝试验

对乔砧短枝型苹果实行篱壁形整枝，比自由纺缍形结果早、产量高，可有效地改善果实品质。且管理省工，省药，提高经济效益。与国外苹果篱壁形整枝相比，无需拉铅丝，立支柱，大幅度减少了建园投资。     

Patterns of abundance and movement in relation to landscape structure: a study of a common scarab (Canthon cyanellus cyanellus) in Southern Mexico

Few relevant data are available to analyze how landscape features affect the abundance and movement patterns of tropical insects. We used mark-release-recapture techniques to study the effects of landscape structure and composition on habitat preferences and movements of Canthon cyanellus cyanellus individuals, within a complex tropical deciduous forest landscape in South Mexico during 2004 and 2005. In total, 2,460 individuals of C. c. cyanellus were captured, including 1,225 females and 1,235 males, out of which 124 individuals (65 females and 59 males) were recaptured once, and 9 individuals (seven females and two males) were recaptured twice. The abundance of individuals was equally high in large forest fragments, small forest fragments and hedgerows, but the abundance in pastures was less than half of the abundance in the other habitat types. To disentangle the movement behaviour of the species from the spatially and temporally varying sampling effort, we applied a Bayesian state-space modelling framework with a diffusion based movement model. Males showed generally faster movement rate than females, and they moved faster within forests and hedgerows than within pastures. Contrary to the assumption of the diffusion model, individuals did not move in a continuous fashion, indicated by the large fraction of individuals that were recaptured in the site of release. However, the posterior predictive data did not deviate substantially from the real data in terms of the mean and maximum movement distances recorded, and in terms of the dependence of movement distance on time between captures. Our results suggest that an important component of the biota in Mexican agro-pasture landscapes can utilize contemporary landscape elements such as hedgerows or small forest fragments in addition to large fragments of remnant habitat. These habitats are still locally common in semi-natural ecosystems and require less intensive conservation management.     

Effects of Different Tree Species on Growth and Yield of Mung Bean (Vigna radiata (L.) Wilczek) Grown in Hedgerow Intercropping Systems in Sri Lanka

Reduction of crop yields due to resource competition from tree hedges is a serious drawback of hedgerow intercropping. This work quantified the competition of six potential hedgerow tree species ( Calliandra calothyrus , Desmodium ransonii , Flemingia congesta , Gliricidia sepium , Cassia spectabilis and Tithonia diversifolia ) on mung bean ( Vigna radiata ) grown as hedgerow intercrops at Pallekelle in the mid-elevational (367 m above sea level), subhumid (rainfall of 1400 mm year⁻¹) zone of Sri Lanka. Leaf area, total biomass and yield of mung bean in hedgerow intercrops showed a clear reduction closer to the hedgerows, whereas no such reduction was observed in a sole crop of mung bean. At 30 cm from the hedgerow, growth and yield of mung bean were significantly lower than in the sole crop, indicating significant competition from hedgerows. However, growth and yield of mung bean increased with increasing distance from hedgerows so that, at 150 cm, mung bean under Gliricidia and Desmodium showed significantly greater growth and yields than the control. In contrast, even the maximum mung bean yields under the rest of the species did not reach that of the control. The differences in competition with different hedgerow species are discussed in terms of variations between tree species in biomass production, quality of prunings and the possibility of root competition.