徐州地区双孢蘑菇覆土中重金属含量测定及其污染评价

为了解徐州地区双孢蘑菇覆土重金属污染状况,选取睢宁县官山镇(SNGS)、泉山区桃园街道办事处(QSTY)、贾汪区江庄镇(JWJZ)、丰县欢口镇(FXHK)4个主栽区,采集48个覆土样品,分别测定其重金属Pb、Cd、As、Hg含量,并进行污染评价。结果表明:QSTY和FXHK覆土中As、Hg含量和FXHK覆土中Cd含量均高于土壤背景值,其中Cd含量达到土壤背景值的2.062倍;4个主栽区覆土中4种重金属的单因子污染指数和综合污染指数分别小于1.0和0.7,显示覆土污染等级为安全;而As含量分别与Pb、Cd含量呈显著和极显著正相关,Pb与Cd含量间呈显著正相关,说明这几种元素存在复合污染的可能,且主要来源于成土母质和农业活动。由此可见,该地区4个双孢蘑菇主栽区覆土重金属质量属于清洁水平,符合无公害食用菌生产条件。     

关于林道开发效率评价的研究

本文在论证和分析影响林道开发效率的主要因子的基础上,提出了用林道开发效率系数来评价林道开发效率的方法。这是评价林道开发效率的一种简单而实用的新方法。研究结果表明,按林道开发效率系数趋近于1时所对应的路同密度来修建林道,可获得最佳的伐区开发效率。     

河南省农业综合生产能力的评价研究

本文建立了农业综合生产能力的评价指标体系，讨论了两种评价方法，并通过计算机测评系统，对河南省农业综合生产能力进行了系统的测算和分析。     

近５０年辽西北半干旱区降水变化与 花生水分适宜性评价

辽宁省花生优势区域的拓展及转移受多种因素制约,且以降水量的制约最为明显。为探讨辽宁花生产业的区域布局及拓展空间,以阜新近50 a的降水变化为例,采用降水保证率、降水变率、土壤水分蒸发量及土壤水分盈亏特征等参数分析辽西北降水规律,并进行花生水分适宜性评价。分析表明,“十年九旱”仍是辽西北基本气候特征,且这种特征可能有继续恶化趋势。该区域4-5月的降水保证率偏低,土壤缺水量达100 mm ,冬春季的降水变率大于110％,发生春旱的机率最大,对花生春播极其不利。而从花生生长季节水分分析,辽西北的降水条件基本能够满足花生生长对水分的需求,且花生生物产量 y与降水量x间显著服从于方程y＝ a＋ bx ,相关系数 r＝0．999。从区域可持续发展角度出发,辽西北花生生产需着重攻克避旱播种、生态防风蚀和避免与粮争地等三个方面的技术难点。     

凤山县耕地地力评价研究

为了弄清凤山县耕地地力等级情况,以凤山县测土配方施肥和第二次土壤普查等数据资料为基础,利用GIS技术和县域耕地资源管理信息系统,对凤山县耕地地力等级情况进行评价研究。结果表明,凤山县耕地地力等级可分为六个等级,一、二级的耕地占耕地总面积的13.15%,是高产稳产耕地;全县耕地地力等级以三至六级为主,占耕地总面积的86.85%,是凤山县粮食、水果和经济作物生产的主要基地,也是主要的中低产耕地。     

桃果实品质评价因子的选择

为了给桃品质评价指标的确定提供理论依据，该文研究测定了北京市郊栽培的水蜜桃、蟠桃、油桃3个品系的19个品种桃的可溶性固形物、可滴定酸、固酸比等主要品质指标，并采用“主成份分析”和“聚类分析”法对各品质指标进行分析。结果表明，在桃多个品质指标变量之间存在着相对独立性和密切相关性，经主成份分析后将许多相关的随机变量压缩成几个综合指标，通过系统聚类分析把多个品质指标分成了5类，最终将品质指标简化为单果重、硬度、水分含量、固酸比和风味5个具代表性的指标；又通过“合理—满意度”和多维价值理论的合并规则进行综合评价，评价结果为，水蜜桃品系中晚蜜、绿化9号和北京38号的表现性较好；蟠桃品系中以瑞蟠1号和碧霞蟠桃品质较优；油桃品系中品质最佳的为瑞光19号。这一结果与感官评价所得结果有高度正相关性。     

福建省开发生产建设项目水土保持监管情况调查与思考

开展开发生产建设项目水土保持监督管理情况调查,掌握水土保持监督执法对象的基本情况,为各地开展水土保持监督执法和水土保持信息化管理工作提供必要的基础信息,提高水保监督执法工作的针对性和有效性。本文就福建省开发生产建设项目水土保持监管情况调查的基本情况和存在问题,做进一步分析和评价,提出了今后如何提高开发生产建设项目水土保持监督管理的工作思路。     

基于数据流的土地适宜性评价系统设计

该文在对面向数据流的系统设计方法介绍的基础上,将该方法运用于土地适宜性评价中。通过对土地适宜性评价系统数据分析获得土地适宜性评价系统数据流模型即分层数据流图;并根据土地适宜性评价系统数据分析结果进行结构设计获得系统结构图;最后根据系统结构实现土地适宜性评价系统。通过面向数据流的系统设计方法,提高了土地适宜性评价设计的效率和准确性。     

Performance of forest groups in achieving multifunctional forestry in Flanders

The forest group is a new policy instrument in Flanders (northern Belgium) to realise multifunctional forest management. This group was introduced in 1995 and organises the various kinds of forest owners, private as well as public, on a local basis (mean working area 751 km²), with voluntary participation (as in all forest owner organisations). This study evaluates forest groups in Flanders through an analysis of their relevance, effectiveness, utility and implementation. The targets of forest groups are relevant to the evolving needs and priorities at the local, regional, national and international level. The effectiveness analysis reveals that most indicators — including the quantity of timber harvest, the number of members, the forest area with an accepted management plan, the area under management and the area with small-scale ecological measures — have been improving between 1995 and 2004. The utility analysis emphasises that the owners are motivated because the forest group provides information and increases knowledge, includes the owner into a collective management plan, offers a platform for sharing management experiences and acts as a union force against the government. However, the forest group is not the solution to introduce multifunctional forest management by all forest owners. The implementation analysis identifies a number of impeding factors, including the imbalance between rights and duties, inconsistencies between various policy aims, and failure of forest groups to act as a common forum for all stakeholders in their working area.     

Evaluation of wheat and emmer varieties for artisanal baking,pasta making,and sensory quality

Identifying varieties best suited to local food systems requires a comprehensive understanding of varietal performance from field to fork. After conducting four years of field trials to test which varieties of ancient, heritage, and modern wheat grow best on organically managed land, we screened a subset of varieties for bread, pastry, pasta, and cooked grain quality. The varieties evaluated were three lines of emmer (T. turgidum L. ssp. dicoccum Schrank ex Schübl) and eleven lines of common wheat (Triticum aestivum L.), including two modern soft wheat varieties, four soft heritage wheat varieties, four hard modern wheat varieties, and one hard heritage wheat variety. A diverse group of bakers, chefs, researchers, and consumers compared varieties for qualities of interest to regional markets. Participants assessed differences in sensory profiles, pasta making ability, and baking quality for sourdough, matzah crackers, yeast bread, and shortbread cookies. In addition to detecting significant differences among varieties for pasta, sourdough, and pastry quality, participants documented variation in texture and flavor for the evaluated products. By demonstrating which varieties perform best in the field, in the bakery, and on our taste buds, these results can support recommendations that strengthen the revival of local grain economies.