混农林业：现状和问题

本文阐述了混农林业的传统模式与建立实践模式两种不同的调查和评价方法,介绍了混农林业类型的划分、组分间关系及与环境相互效应的研究,提出混农林业是解决山区生态环境问题的有效技术之一。     

Soil bacterial communities under slash and burn in Mozambique as revealed by a metataxonomic approach

The slash-and-burn system is a subsistence agronomical practice widespread in tropical areas worldwide. This system has been extensively studied,especially for its impacts on agronomical aspects and soil physicochemical properties; however, knowledge of soil microbial diversity under slash and bum is scarce. In this study, for the first time, soil bacterial diversity of three locations from Central Mozambique, where slash and burn has been practiced for different durations of the forest fallow p...     

重庆璧山5种典型农林混作模式土壤理化性质及水分入渗特性

利用野外调查和室内分析相结合的方法,研究璧山县血橙—红薯、血橙—花生、血橙—玉米、血橙—茄子、血橙纯林5种模式下土壤理化性质及入渗过程.结果表明:不同模式下土壤容重、孔隙度差异均显著,血橙—红薯模式土壤容重最小,孔隙度最大,血橙纯林土壤容重最大,孔隙度最小;不同模式土壤化学指标差异显著,血橙纯林下土壤各化学指标含量均最低,而血橙—茄子模式土壤有机质及速效钾含量最高,血橙—玉米的全氮及碱解氮含量最高,血橙—红薯模式的全磷、全钾含量最高,血橙—花生模式的有效磷含量最高.不同模式土壤入渗过程不同,入渗曲线斜率不同,血橙—红薯模式达到稳渗时间最长,在50～55 min,血橙—红薯模式土壤初始入渗率、稳定入渗率、平均入渗率最大,分别为血橙纯林的4.82,3.88,4.28倍,而血橙纯林的累积入渗量仅为血橙—红薯模式的25.76％;不同模式土壤入渗能力与土壤容重呈负相关,与孔隙度呈正相关,与有机质相关性不显著.采用入渗模型模拟各模式入渗过程,Horton模型拟合效果较好,决定系数最高,模型参数具有物理意义,是分析和预测璧山血橙林与农作物混作下土壤入渗过程的适宜模型.     

A CASE FOR ASSESSING ALLOCASUARINA AND CASUARINA SPP. FOR USE IN AGROECOSYSTEM IMPROVEMENT IN SEMI-ARID AREAS WITH A FOCUS ON CENTRAL ANATOLIA,TURKEY

• Semi-arid ecosystems have been especially impacted by a long history of clearing, cropping and intensified grazing. • Selection of tree species for assessment for agroforestry needs to consider their utility and effectiveness in provision of ecosystem service, but also the wider consideration of preserving biodiversity. • Imperatives of agroecosystem services and biodiversity conservation (or restoration) will impact on species selection for agroforestry. • The potential of Allocasuarina and Casuarina for wider economic and ecosystem needs an endeavor to achieve demonstrable gains. Agroecosystems in water-limited contexts— Mediterranean, semi-arid and arid climatic zones—are too frequently degraded systems that will not provide the needed ecosystem services to ensure a future of sustainable agricultural production. The processes that have created this situation continue and are being accelerated by anthropogenic climate change. Increasing arboreal vegetation in these areas through agroforestry is an important strategy to conserve and improve their agroecosystems. Actinorhizal trees and shrubs in the Casurinaceae have a unique set of adaptations for heat and water stress, and/or infertile to hostile soils. Central Anatolia, Turkey is particularly at risk of increasing aridity and further degradation. Therefore, species of Allocasuarina and Casuarina have been evaluated for their potential use in agroecosystem improvement in semi-arid areas with a focus on Central Anatolia. Based on a semiquantitative environmental tolerance index and reported plant stature, eight species were identified as being of high (A. verticillata and C. pauper) to moderate (A. acutivalvis, A. decaisneana, A. dielsiana, A. huegeliana, C. cristata and C. obesa) priority for assessment, with none of these species having been adequately evaluated for agroforestry deployment in semi-arid agroecosystems in any context.     

孟加拉无机肥料对几种农林作物生物固氮和种苗生长的影响(英文)

比较了不同浓度无机肥料(尿素和重过磷酸钙)对四种农林作物(楹树、雨豆树、相思树和印度田菁)生物固氮和种苗生长的影响。种子萌发一个月后利用不同浓度肥料(尿素:40kg·hm-2,80kg·hm-2;重过磷酸钙:40kg·hm-2,80kg·hm-2;(尿素 重过磷酸钙)40kg·hm-2和(尿素 重过磷酸钙)80kg·hm-2)处理种苗。结果表明:中等浓度无机肥料促进了种苗的生长,但较高浓度无机肥料也不利于种苗的生长。当施加尿素时根瘤菌的数量大小明显受抑制,但随着增加磷肥(重过磷酸钙)根瘤菌的数量大小增加。本研究有助于农业人员利用无机肥料改善土壤提高农林作物的生物固氮和种苗生长。图2表6参33。     

陇南山区农林复合模式划分与种植结构研究

甘肃省陇南坡耕地占总耕地面积的80.15%。坡耕地及不合理的耕作方式是造成水土流失的主要原因之一,在山坡地及梯田中进行农林复合栽培,可提高土地产出率,有效防治水土流失。根据生产方式和栽培结构将陇南山区农林复合栽培的模式种类划分为林药复合、林粮间作、田间地埂利用、果菜种植、特种林粮复合、庭院经营、小流域综合治理、林草复合等8种农林复合栽培模式,以便在坡改梯、退耕还林等生态工程中较好地应用复合农林业技术。     

Traditional versus improved agroforestry systems in Vietnam: a comparison

Combined with the diverse biophysical and social heterogeneity encountered in the northern mountains, the socioeconomic changes in Vietnam that accompanied the decollectivisation process led to complex agrarian dynamics that today challenge traditional farming and management of natural resources. Data for this study were collected from villages in and around Ba Be National Park (BNP) in the Bac Kan Province located in the northern mountains of Vietnam. Traditional slash and burn cultivation is no longer a sustainable practice in Vietnam. The main challenges in the region are to protect biodiversity, maintain the land productivity and simultaneously support local livelihoods. The study shows that improved agroforestry cultivation could provide significantly higher productivity and income per unit of land, besides decreasing pressure on natural forests. The challenge to protect biodiversity is not met, as improved agroforestry implies less tree species. From an institutional and socio‐economic perspective, it is not easy for local communities to readily adapt to improved agroforestry. New systems must be tailored site‐specific to the diverse local conditions of resource‐poor farmers. Copyright © 2006 John Wiley & Sons, Ltd.     

农林院校文科研究生创新能力培养探析

由于农林院校中有关教学评价、教学方式、学科定位之中存在的问题,导致农林院校文科研究生创新能力缺乏。究其原因,在于培养方式缺失、课程与教学制约、师资队伍缺位及管理模式滞后。为此,需从实践锻炼、课程调整、导师队伍、管理体制方面的优化来提高农林院校文科研究生创新能力。     

基于Probit-ISM模型的农户林农复合经营行为影响因素分析

基于苏北27个村302户林农的调研数据,利用Probit模型和ISM模型,分别探究农户林农复合经营行为的影响因素及各因素间的关联性及层级结构。研究结果表明:户主的年龄、性别、家庭人口规模和对农林业相关政策的了解程度在5%水平上显著;户主的学历水平、家庭年收入、林地面积、是否加入合作社、是否有农技推广站和贷款意愿在1%水平上显著。其中,家庭年收入、是否有农技站和贷款经营意愿是表层直接因素,林地面积和对相关政策的了解程度是中层间接因素,家庭人口规模、户主的学历水平和是否加入合作社是深层根源因素。     

Establishment of Prosopis cineraria (L.) druce in the hot deserts of India

Prosopis cineraria (L.) Druce, commonly known as Jandi, is a deep rooted, nitrogen fixing, multipurpose tree endemic to the hot deserts of India. These trees are the essential component of the agroforestry land use system in these parts of India. The shade-intolerant tree reproduces poorly in nature and is difficult to propagate vegetatively. Germination up to 86.6% was observed after 15 days in seeds soaked in water at room temperature for 72 h. In another treatment, pouring of boiling water twice (at 0 and 6 h) over seeds and germinating after 12 h produced germination rates of 92.6%. Field establishment of containerized transplants in polythene bags (22×10 cm; 150 gauge) gave 90.3% survival after 6 months and 75.4% survival after 24 months. Seedlings were irrigated once during transplanting with 15 1 water. Bare root transplants and manual direct seeding after 6 months had a survival of 30.8 and 45.0%, respectively. Increased levels of nutrients (N, P and K), moisture content and organic carbon were observed under plantations as compared to open areas.