湘南丘陵区林下间种作物生产量与泥沙流失量的关系研究

通过对湘南丘陵区林下间种农作物和泥沙量的定位测定研究，分别对林下间种的花生、油菜的覆盖度与输沙率和花生、油菜各组成部分的生产量与泥沙量的关系进行了探讨，并建立了林下间种花生、油菜覆盖度的动态变化与输沙率的关系式和花生，油菜各种组成部分生产量对泥沙流失量影响的关系式。     

Taungya in Nigeria: Tree planting time and fertilizer effects on growth and crop yield

The growth of Gmelina arborea, a forest crop tree, and the yields of food crops as affected by tree planting time and fertilizer levels, were investigated in taungya experimental research farms spread over four vegetational zones of southern Nigeria. Yields of food crops were depressed significantly (P < 0.05) when both the tree and food crops were planted at the same time or within a period of less than 1 month. Yield reductions of food crops due to planting time of tree crops were 13%, 25%, and 31% for maize, yam, and cassava, respectively. Early-planted Gmelina seedlings performed markedly well in terms of height and girth increments, probably due to exposure to a longer period of rainfall and soil nutrient availability. Trees planted in May, June and July reached a mean height of 1.97, 1.44 and 0.74 m, respectively, by the following December while the equivalent girths were 17.7, 11.6, and 7.6 cm. Whereas application of 15:15:15 N:P:K fertilizer significantly increased agricultural yields, it tended to depress the girth increment of young Gmelina forest tree crops, possibly due to competition for space and light with the food crop.     

Improving agroforestry in Nigeria: Effect of plant density and interaction on crop production

The performance of Gmelina arborea forest tree crop and the yields of food crops as affected by their planting distances and crop combinations when intercropped in an agroforestry farm were investigated in six different ecological areas of southern Nigeria. The percentage survival and mean height of Gmelina arborea were not significantly affected by the different planting densities of Gmelina and food crops. However, the yields of yams (Dioscorea rotundata), maize (Zea mays) and cassava (Manihot utilissima) depended greatly (P = 0.01) on the planting densities of these food crops. Yams and maize were found to combine adequately with young Gmelina tree crop at spacings of 1 × 1 m and 2.5 × 2.5 m for the food and forest crops respectively in the areas studied.     

Growing environment and container type influence field performance of black spruce container stock

Black spruce (Picea mariana [Mill.] B.S.P.) overwintered container crops produced in four container types spanning a range of container sizes and seedling rearing densities were compared for two consecutive years. In 1989 two growing environments (greenhouse and outdoors) were compared. In 1990 three growing environments (greenhouse, coldframe, and outdoors) and two hardening regimes (short day and natural) were compared. Seedlings were outplanted during the spring of 1989 and 1990 and total height and survival were assessed for five years.The outdoor-grown crop was shorter, smaller in root collar diameter and had less dry weight at time of planting than the crops produced in the greenhouse (1989 study) and in the greenhouse and coldframe (1990 study). Although the greenhouse crops in both studies were larger at time of planting, the outdoor-grown crops (1989 and 1990) and coldframe-grown crop (1990) displayed significantly greater annual height increment in the first two years after planting. The enhanced early height growth of the outdoor-grown crops may be due to the natural acclimation created by their growing environment.Seedlings grown in a large volume container, at a low plant density (441 plants/m²), had significantly larger root collar diameters and total dry weights at time of planting than seedlings grown in a smaller volume container at a high plant density. Stem volume production in the field was greater on seedlings from larger volume containers grown at low densities.     

农林业系统工程与农桐间作的结构模式

国名{造林树种}一’造林方式及生长量}备注日·…::‘“馨双__…一煲忿童筹;嘿哼6万株’当‘产量…力口重物髻翼子矗羹羹、‘材二….按树.….2。竺鬓:;:,收获后萌.芽更‘,年均生长‘…生一 …·…·短轮伐期:伐期l。·,株行足巨3·3。,预计·… 卜、…、卿咖,树高‘sm,年均生长歇。一30ms/ha。{ }}超短轮伐期:伐期l一3年,株行距。.3xo.gm,}用于造纸工业,也适用于 加拿大}白杨{{ }…干物质年均生长量为15t/hao{能源。 {{中短轮伐期’伐翔5一6年,“固氮植物混植,} {{收获后萌芽更新。}一…鬓:羹攫、!方翼二熏轰氨“;!Zt/ha。开展栽植密度、育…     

林下经济模式及其产业发展对策

林下经济是一种高效的林业循环经济,是进一步拓宽林业经济领域、促进农民增收和新农村建设的重要途径,也是发展现代林业的必由之路。笔者在概述国内外林下经济发展的基础上,总结了中国林下经济的主要经营模式,分析了中国林下经济发展中存在的问题,提出了林下经济产业发展的对策,以期为促进林下经济的发展提供依据。     

Improving the Traditional Acacia Senegal-Crop System in Sudan: The Effect of Tree Density on Water Use, Gum Production and Crop Yields

The traditional Acacia senegal bush-fallow in North Kordofan, Sudan, was disrupted and the traditional rotational fallow cultivation cycle has been shortened or completely abandoned, causing decline in soil fertility and crop and gum yields. An agroforestry system may give reasonable crop and gum yields, and be more appealing to farmers. We studied the effect of tree density (266 or 433 trees ha⁻¹) on two traditional crops; sorghum (Sorghum bicolor) early maturing variety and karkadeh (Hibiscus sabdariffa), with regard to physiological interactions, yields and soil water depletion. There was little evidence of complementarity of resource sharing between trees and crops, since both trees and field crops competed for soil water from the same depth. Intercropping significantly affected the soil water status, photosynthesis and stomatal conductance in trees and crops. Gum production per unit area increased when sorghum was intercropped with trees in low or high density. However, karkadeh reduced the gum yield significantly at high tree density. Yields of sorghum and karkadeh planted within trees of high density diminished by 44 and 55% compared to sole crops, respectively. Intercropping increased the rain use efficiency significantly compared to trees and field crops grown solely. Karkadeh appears to be more appropriate for intercropping with A. senegal than sorghum and particularly recommendable in combination with low tree density. Modification of tree density can be used as a management tool to mitigate competitive interaction in the intercropping system.     

泥质海岸林农复合经营模式建立与经济效益研究

在辽宁省泥质海岸地区的新植林地或幼龄林间隙地,采用林农复合措施,以林作为屏障,以市场经济为导向,间种农作物,生产粮食食品（玉米、大豆等）、饲草（苜蓿、田菁等）、林产品（紫穗槐、柠条等）、经济作物（蓖麻、月见草等）,并对其经济效益进行分析,建立了多种林农复合型栽培模式。     

Photosynthesis,growth and yield of soybean and maize in a tree-based agroforestry intercropping system on the Loess Plateau

Agroforestry is the most effective way to restore the disturbed lands on the Loess Plateau and to develop the poor local economy. In order to maximize the potential benefits of tree-based intercropping systems, photosynthesis, growth and yield of soybean and corn were studied by measuring photosynthetic active radiation (PAR), plant water deficit and soil moisture in a 4-year-old plantation of walnut (Juglans regia L.) and plum (Prunus salicina) grown at a spacing of 5 m × 3 m on the Loess Plateau. The effects of tree competition significantly reduced PAR, net assimilation (NA), growth and yield of individual soybean or corn plants growing nearer (1 m near tree row) to tree rows. NA was highly correlated with growth and yield of the both crops. These correlations were higher for corn than soybeans, with corn, rather than soybeans being more adversely impacted by tree shading. Plum, rather than walnut had the greatest competitive effect on PAR and NA. Daily plant water deficits were non-significantly and poorly correlated with NA and growth and yield of the both crops. However, soil moisture (20 cm depth) was significantly correlated with biomass and yield of both crops. Possible remediation strategies are discussed to reduce tree competitive interactions on agricultural crops.     

Growth and resource utilization of perennial pigeonpea (Cajanus cajan (L) Millsp.) at the tree-crop interface

Perennial pigeonpea (Cajanus cajan (L) Millsp.) was grown as a multipurpose tree species in strips or blocks with annual crops (sorghum, sunflower and chickpea) on a shallow Vertisol from 1987 to 1989. The interaction between the perennial pigeonpea and annual crops was measured at the tree-crop interface (TCI) by comparing the plants at the interface (I) and in the middle of the block planting (N).Perennial pigeonpea I plants had significantly more branches and bigger stems than N plants at the onset of the following rainy season. The greater number of flowers and grains of the I pigeonpea plants was partly due to a better lateral light level and partly due to a better access to water. On the other hand the negative effect on annual crops at the TCI extended to 1.5 m during the rainy season and to 2.5 m during the post-rainy season. Significant reduction in the growth of annual crops occurred at 30–40 days after sowing and was associated with the shading by the taller pigeonpea. Measurements of root profile of pigeonpea at the interface indicated that competition for moisture was the major cause for yield reduction of chickpea during the post-rainy season but an allelopathetic effect may also be involved. The results are compared with other TCI studies especially with Leucaena leucocephala in the semi-arid crops and the possible mechanisms for moisture interaction at the TCI are discussed.Submitted as ICRISAT Journal Article No. 1176 for Agroforestry Systems.     

农防林胁地发生规律及防治对策

农田防护林可防风固沙,蓄水保土,调节气候,防止自然灾害气象因素等危害,为农作物生长、高产、稳产创造适宜条件.但是,农田防护林带对邻近农田作物产生不利影响,即所谓的“胁地”,造成农作物减产.通过对四子王旗农防林胁地规律的研究,提出相应对策.     

太行山区浆水镇土地资源优化配置研究

山区土地资源优化配置的主体核心是确定各种农作物、林果、牧草资源的占地比例及规模。装水镇土地资源优化配置利用方向,在于建设发展以板栗、苹果为主的林果生产基地,畜牧养殖业在于发展以消耗饲草为主的大牲畜(主要是牛)和山羊,另外,种植在5级地上的粮食作物,应以旱作为主。     

Eucalyptus in agroforestry: its effects on agricultural production and economics

The economics of eucalyptus in agroforestry and its effects on agricultural crops have been studied with the help of observations made during the harvests in agricultural fields and from the information supplied by progressive farmers. Three rotations of eucalyptus in agroforestry were selected for comparative study of its returns and relative loss to the crops, in order to ascertain the optimum rotation: i.e. the one giving the maximum internal rate of return with minimum loss to agricultural crops.     

Tree crop based agroforestry in Nigeria: a checklist of crops intercropped with cocoa

A survey of cocoa farmers in Bendel, Ogun, Ondo and Oyo States of Nigeria, carried out in 1985, showed that almost all the farmers intercropped other crops with cocoa. The intercrops included food crops such as plantain (92.3), cocoyam (85.7%), cassava (51.3%), yam (41.3%), maize (38.9%), melon (31.4%), cowpea (28.6%) and pineapple (26.0%) and tree crops such as oil palm (71.5%), kola (67.3%), coffee (41.0%), coconut (7.9%) and citrus (7.2%). Other crops are ewe-iran (Sarcophrynium brachystachys) and ewe-gbodogi (Megaphrynium macrostachyum) (45.2%), african walnut (Tetracarpidium conophorum) (42.2%), aligator pepper (Aframomum melegueta) (31.6%), and iyere (Piper guinense) (20.2%). Guava, mango, pawpaw and vegetables such as celosia, okra and solanum occur in cocoa plots at rather low frequencies. As many as six or more other crops can be intercropped with cocoa at the same time.     

云南保山地区杉木的混农林模式及效益分析

云南保山地区农村用杉木为主的用材林树种与农作物间作的造林方式对村社林业的发展起着积极的促进作用, 并能够长期、稳定地发挥着良好的社会、经济和生态效益, 其主要间作模式有杉木＋ 农作物、杉木＋ 茶叶＋ 农作物。本文在对主要杉木混农组合类型介绍的基础上, 对其效益进行了分析。     

Effect of adult age and insect density of <Emphasis Type="Italic">Dicyphus tamaninii</Emphasis> Wagner (Heteroptera: Miridae) on progeny

The polyphagous predator Dicyphus tamaninii is widely used in IPM programs on horticultural crops in the Mediterranean basin, where it is commonly found in natural populations. The development of a mass-rearing protocol is necessary to ensure the permanent availability of this predator for potential introductions into crops. Introductions occur mainly in those periods of the year when the predator is not present in enough quantities to spontaneously colonize the crops, as well as to guarantee its presence in IPM horticultural crops. The effects of two different adult ages and three densities (number of individuals/cage) on mortality and production of D. tamaninii were evaluated in order to develop a mass-rearing protocol. The adult age had an effect on mortality but did not affect the final production (number of adults + nymphs/female/day). On the contrary, the increased number of adults in the cages had a strong increasing effect on mortality while reducing final production. These results are of highly important for the development of a mass-rearing protocol for this natural enemy.     

The spatial and temporal effects of paulownia intercropping: The case of northern China

We present a financial analysis and further statistical tests of the spatial and temporal effects of intercropped paulownia (Paulownia elongata) trees on crop yields. The results provide evidence that growing paulownia trees in farm fields can either increase or decrease crop production, depending on the manipulation of the tree density and rotation length. A 60–100% reduction of crop yields can result from a higher tree density and/or a later stage of the rotation, but the pattern of reduction is different for the first (wheat) and second crops (corn, bean or cotton). However, the reduction in crop yield is accompanied by gains of timber, fuel, fodder, and other goods and services. Thus, although the accumulated net returns from crops decline as tree density increases, the combined net returns of crops and trees are generally higher than those of the control, ranging from 50% to 100%. This revised version was published online in June 2006 with corrections to the Cover Date.     

公路土壤重金属污染对农作物的影响

探讨了公路旁土壤重金属污染对农作物的质量和产量的影响,土壤中重金属含量与农作物中的重金属含量之间的关系以及重金属在农作物不同器官的积累分布等,旨在对公路重金属污染的防治及公路旁农作物的种植提供科学依据。     

Land suitability evaluation for multiple crop agroforestry planning using GIS and multi-criteria decision analysis: A case study in Fiji

We present novel methods that use geographic information systems (GIS) and multi-criteria decision analysis (MCDA) to evaluate land suitability for a set of seven agroforestry crops, with the aim to differentiate relative land suitability and its potential to achieve different benefit goals for the Sigatoka Valley, Fiji. Our first model (Land Suitability) identifies optimal areas for each crop based on readily available edaphic and environmental cultivation criteria and common GIS datasets. The second model (Weighted Maximum) uses objective approaches for weighting the relative importance of target crops to derive a multi-crop suitability map. We use the analytical hierarchy process (AHP) technique (a form of MCDA) to identify the relative importance of five benefit types (i.e. agroforestry initiative goals/AHP Objectives). AHP criterion weights were used to map the most important crops for different agroforestry goals. Our methods are unique among GIS-MCDA applications of land suitability analysis in that our aim was to investigate and spatially evaluate land use suitability for multiple crops on a per-crop basis, whereas the aim of most GIS-MCDA land suitability analyses is to evaluate relative suitability (e.g. low, medium, high), evaluate potential for different land uses (e.g. production, intensive, or multifunctional) or land suitability for a single crop. We conclude that the methods described can be adapted to agroforestry initiatives and other similar land use suitability applications in the Pacific region and other geographical settings.

     

Productivity status of traditional agrisilviculture system on northern and southern aspects in mid-hill situation of Garhwal Himalaya, India

The productivity of traditional agrisilviculture system (agricultural crops + trees) was investigated in the northern and southern aspects of mid-hill situation in Garhwal Himalaya, Uttarakhand, India during the 2004-2006. A total of 19 tree species were studied in both northern and southern aspects, out of which 17 tree species were selected in northern aspect and 12 tree species in southern aspect for phytosociological characteristic analysis of trees in agrisilvicultural system. The most dominant tree species are Grewia optiva, Celtis australis and Melia azedarach and successively grown under traditional agrisilviculture system. The results show that the annual productivity of all tree species was 3775 kg·ha-1·a-1 in northern aspect (site-N) and 3101 kg·ha-1·a-1 in southern aspect (site-S). G. Optiva had the highest productivity in both site-N and site-S among the tree species, followed by M. Azedarach, Quercus leucotrichophora and C. Australis. The dominant agricultural crops were Eleusine coracana in summer cereals, Phaseolus vulgaris in summer pulses-oilseeds and Triticum aestivum in the winter season in the area. The average biological productivity of agricultural crops in northern aspect was about 16% higher than that in southern aspect under traditional agrisilviculture system. The sole agricultural crop productivity (without trees) in northern aspect was also higher than that in southern aspect. An obvious difference in annual productivity of trees and agriculture crops was observed between northern aspect and southern aspect. The overall productivity in traditional agrisilviculture system (crop + tree) was 24% (in northern aspect) and 21% (in southern aspect) higher than that in sole cropping system.