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Throughout Australia thousands of volunteers are engaged in Landcare projects that should help rehabilitate degraded landscapes. Many of these projects involve tree planting, but their seed is not necessarily of local provenance. Based on a survey of 85 Landcare groups working in the Hawkesbury–Nepean catchment, data were collected about Landcare groups' knowledge of their seed source, understanding of local provenance and the ecosystem in which they were planting trees and the source of funding for their projects. The findings from the study indicate that about one in five (21%) of the groups surveyed that introduced plant material were not aware of local provenance issues. Indirect indications were that a large number of Landcare groups state-wide may be doing more harm than good to the landscape while trying to rehabilitate it. The data also showed that one in seven (13%) of the groups funded by the Australian Government through the Natural Heritage Trust (NHT) had limited awareness of local provenance issues. With millions of dollars being spent on 'works on the ground', it would be prudent to allocate some funds to document and monitor current Landcare activities, so that the environmental outcomes can be quantified and more effective Landcare policies can be developed in the future. 相似文献
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对崇信县甘薯气候适应性分析发现,在栽苗到封垄期温度偏低,而封垄前覆膜可解决热量不足问题;水分条件基本能满足甘薯生长需要。采用适当种植技术,可使甘薯获得较高产量。 相似文献
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王小军 《沙漠与绿洲气象(新疆气象)》2020,14(1):138-143
为探求绿洲棉区膜下滴灌条件下不同种植密度棉田蒸散发规律,运用大型称重式蒸渗仪对膜下滴灌棉田蒸散过程连续监测,结果表明:在不同种植密度条件下,棉花的日蒸散量曲线都表现为单峰曲线,不同生育时期一膜六行(30株/m2)种植的棉田蒸散量比一膜四行(20株/m2)大,花铃期棉田的蒸散发强度最大,一膜四行、一膜六行分别为4.76mm/d、5.94mm/d。同时,一膜六行种植的叶面积指数大于一膜四行种植,株高小于一膜四行种植。花铃期棉田的蒸散发量与日平均气温(p<0.01)和空气相对湿度(p<0.01)具有很好的相关性,与日平均风速和日平均水汽压的关系不大。 相似文献
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湖泊是对环境变化响应敏感的地理单元,湖泊消长与响应机制研究对维持区域生态系统稳定具有重要意义。基于1999—2018年Landsat、气象、水文和农业种植面积等多种数据,在ArcGIS平台中利用改进归一化差异水体指数(MNDWI)及目视修正方法提取了乌兰布和沙漠东南缘湖泊群空间信息,运用统计学方法对主要驱动因子与湖泊消涨的关系进行了分析。结果表明:1999—2018年乌兰布和沙漠东南缘大湖泊(面积大于100 hm2)在面积上占优势,小湖泊(面积小于100 hm2)在数量占优势。趋势分析表明大湖泊面积和数量呈显著性减少趋势(相关系数分别为R=0.624 > R18,0.01=0.561和R=0.648 > R18,0.01=0.561);小湖泊减少趋势不显著。在空间分布格局上,研究区中部是大湖泊稳定分布区,大湖泊数量11~23个,面积2 208~4 581 hm2。研究区湖泊消长主要受到年实际引黄水量、农田面积和地下水埋深的影响。其中,实际引黄(河)水量影响所有湖泊(P≤0.01),而农田面积和地下水埋深分别对大湖泊(P≤0.01)和小湖泊(P≤0.05)影响显著。用这3个因子分别构建的多元回归模型显示,在大、小湖泊面积和数量预测方面,精度分别达到75.7%和60.5%以上。 相似文献
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利用遥感技术,使用eCognition软件的面向对象分类技术,对RAPIDEYE卫星影像进行分类识别,从而快速、准确的监测小麦种植面积,为冬小麦财政补贴提供数据和技术支持。以兖州市为例,行政区面积6.501 9万hm2,小麦监测面积3.1715万hm2,小麦面积监测精度达到了90.5%。 相似文献
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《Geografisk tidskrift / udgivet af Bestyrelsen for Det Kongelige danske geografiske selskab》2012,112(2):135-143
Abductive causal eventism (ACE) is an analytical methodology based on a pragmatic view of research methods and explanation that places at the center of research inquiry the answering of ‘why’ questions about events, including human actions or environmental changes of interest. When used in human–environment research, the methodology entails constructing causal histories of interrelated social and/or biophysical events backward in time through a process of eliminative inference and reasoning from effects to causes, called abduction. ACE encourages an eclectic use of methods, models, and theoretical ideas. It fosters integrative, interdisciplinary analysis without being committed either to systems as ontological entities or to holistic analytical frameworks. By not privileging particular theories or explanatory factors in advance, ACE enables researchers to interrogate the plausibility of different causal influences, including local environmental changes that may be related to much wider changes in climate. Likewise, behaviors or practices that may be of value in light of anticipated environmental changes can be studied without their presuming to be caused by these changes or by changes in climate per se. Research on coastal mangrove planting for storm protection in the Philippines and upland tree planting in St. Lucia are used to illustrate these arguments. 相似文献
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金燕平 《沙漠与绿洲气象(新疆气象)》2012,6(3):66-69
利用青河县历史气象资料,通过对比分析青河县与大果沙棘原引种区气候条件,指出青河县适宜种植大果沙棘。在归纳分析青河县种植大果沙棘有利和不利的气候条件基础上,提出了相应的气象服务措施。 相似文献
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