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41.
The establishment of the forest eco-compensation mechanism could realize the value of the forest ecosystem services partly or thoroughly, stress the equality of the stakeholders, encourage public participation in forest ecosystem tendering, and strengthen the capacity of sustainable management. Taking the Hainan province as an example, this study focuses on the analysis of major socioeconomic and ecological impacts of forest eco-compensation in the Qiongzhong County and Lingshui County, and recommends approaches and practices for the establishment of the eco-compensation mechanism in the Hainan Province. Data were collected from a household questionnaire survey. Altogether 120 households have been interviewed, and Statistical Product and Service Solutions (SPSS) was applied for data analysis. Most of the respondents held a positive attitude toward the forest eco-compensation policy which has contributed to the improvement of environmental quality. However, forest protection has limited the opportunities for the income growth of local communities, who have never got sufficient compensation from either the central or local governments. Insufficient financial support to forest institutions and local communities involved in forest management has led to major conflicts in forest management, such as, the conflict between forest protection and local economic development, and decrease in arable land area and increase in surplus labor force. On the basis of case study results, the core issues of forest eco-compensation mechanism in Hainan province are discussed. Finally, suggestions and recommendations that cover forest eco-compensation standards, management institutions, and community capacity building and diversification of financing channels, have been made for the establishment of forest eco-compensation mechanism in Hainan. 相似文献
42.
C. C. Li 《Chemistry and Ecology》1996,12(1):57-66
Water quality was monitored for 12 months in Lake Tai and Lake Zon on Kinmen Island, Taiwan, and physico-chemical conditions were analyzed. No vertical temperature stratification was observed in these shallow lakes. pH is neutral to alkaline and associated with vigorous algal growth. Nitrogen levels are high and present in various forms due to progressive nitrification. Green and blue-green algae play an important part in the process of nitrification.
Assessment of lake eutrophication was made by the use of the N:P ratio, the Trophic State Index (TSI) and the US EPA Eutrophic Screening Model. the result of these calculations indicates eutrophic conditions in both lakes. It is advised that lake restoration be initiated and available techniques are listed. 相似文献
Assessment of lake eutrophication was made by the use of the N:P ratio, the Trophic State Index (TSI) and the US EPA Eutrophic Screening Model. the result of these calculations indicates eutrophic conditions in both lakes. It is advised that lake restoration be initiated and available techniques are listed. 相似文献
43.
雷州半岛与海南岛砖红壤养分比较研究罗凯(广东省徐闻县农村工作委员会,徐闻524100)ComparisonofNutrientsContentofLatosolsinLeizhouPeninsulaandHainanIsland¥LuoKai(Rur... 相似文献
44.
Forty-six trace elements in coastal Casuarina equisetifolia plant–soil systems at nine sampling sites on Hainan Island were analyzed using ICP-MS. The relationships among the trace elements of the same group or the same periodicity of the Periodic Table in the plants and soils were complex and no consistent patterns were found. More combinations of elements occurred with high positive correlation coefficients within the same periodicity than within the same group of the Periodic Table, and there were more high positive correlations in soils than in plants. However, there were many element combinations in Block d (transition elements) with high positive correlation coefficients in plants. Markedly high positive correlation coefficients between individual rare earth elements and Y and among Zr, Nb, Cd existed in both plants and soils. The dendrograms obtained by cluster analysis show that rare earth elements had very similar occurrence and distribution in both soils and plants. Thus, they behaved as a coherent group of elements both geochemically and biogeochemically. The transition elements were more coherent in plants than in soils. 相似文献
45.
海南鹦哥岭的外来植物与生态环境影响评价 总被引:5,自引:0,他引:5
通过对鹦哥岭外来植物的调查,以及外来植物区系的种类组成、原产地、生长型、生境和危害程度等的分析,阐明鹦哥岭的外来植物现状及其对当地生态环境的影响。分析表明:共有53种外来植物,约占鹦哥岭种子植物总数的2.73%,主要来自新大陆热带地区(35种)。其中草本(36种)和灌木(13种)占优势,藤本(3种)和小乔木(2种)相对不明显。外来种对鹦哥岭自然生态系统的影响较小,对人为干扰严重的生态系统影响较大。最后对外来植物进行评估,并提出防控措施。 相似文献
46.
土壤中锌的含量异常会阻碍植物生长.海南岛地处热带地区,上壤中锌的含量为1.85~107.89mg/kg,平均31.46mg/kg;0.1mol/L盐酸提取有效锌含量0.50~9.80mg/kg,平均3.86mg/kg.玄武岩上的土壤含锌量为87.35~107.89mg/kg,滨海砂上含锌量大多不足20mg/kg,其它土类的锌含量大多在15~50mg/kg.除了个别土壤锌含量偏低外,绝大多数土壤锌含量是正常的.土壤锌含量的地理分布是:东北部地区明显高,其次是西南部,再次为西北部、中部和东南部地区,岛四周的滨海砂土地区最低.海南岛的土壤锌含量与母质种类的关系最为密切,玄武岩母质上的比花岗岩的高得多.气候条件也是影响锌含量的重要因素之一,湿润地区锌有向下淋溶的趋势.干热地区锌有上移的倾向.质地粘重的土壤含锌量往往较高.土壤有机质对锌含量的影响不明显. 相似文献
47.
48.
Bats produce echolocation signals that reflect the sensory tasks they perform. In open air or over water, bats encounter few
or no background echoes (clutter). Echolocation of such bats is the primary cue for prey perception and varies with the stage
of approach to prey, typically comprising search, approach, and terminal group calls. In contrast, bats that glean stationary
food from rough surfaces emit more uniform calls without a distinct terminal group. They use echolocation primarily for orientation
in space and mostly need additional sensory cues for finding food because clutter echoes overlap strongly with food echoes.
Macrophyllum macrophyllum is the only Neotropical leaf-nosed bat (Phyllostomidae) that hunts in clutter-poor habitat over water. As such, we hypothesized
that, unlike all other members of its family, but similar to other trawling and aerial insectivorous bats, M. macrophyllum can hunt successfully by using only echolocation for prey perception. In controlled behavioral experiments on Barro Colorado
Island, Panamá, we confirmed that echolocation alone is sufficient for finding prey in M. macrophyllum. Furthermore, we showed that pattern and structure of echolocation signals in M. macrophyllum are more similar to aerial and other trawling insectivorous bats than to close phylogenetic relatives. Particularly unique
among phyllostomid bats, we found distinct search, approach, and terminal group calls in foraging M. macrophyllum. Call structure, however, consisting of short, multiharmonic, and steep frequency-modulated signals, closely resembled those
of other phyllostomid bats. Thus, echolocation behavior in M. macrophyllum is shaped by ecological niche as well as by phylogeny. 相似文献
49.
崇明岛公路两侧蔬菜地土壤和蔬菜重金属污染研究 总被引:11,自引:1,他引:11
为了研究崇明岛公路两侧土壤和蔬菜重金属污染状况,采集陈海、北沿公路两侧蔬菜地土壤、蔬菜和路面灰尘样品,测定重金属Pb、Cd、Cu、Zn含量.结果表明,以上海市土壤环境背景值上限值为评价标准,所有土壤样品Pb、Cd、Cu和Zn的超标率分别为10.1%、25.4%、6.5%和8.7%;以HJ 332-2006 食用农产品产地环境质量评价标准中蔬菜地土壤环境质量评价指标限值(pH值6.5~7.5)为标准,Cd超标率在21.0%,仅有不到3%样品Pb含量超标,而没有样品Cu、Zn含量超标.以国家食品卫生标准中规定的重金属限量为标准,路侧蔬菜样品Pb含量超标率为43.2%,Cd为18.6%,Zn和Cu则小于5%.由此可见,崇明岛主要公路两侧土壤污染以Cd为主,而蔬菜污染则以Pb为主.在长期运营的前提下,低交通量公路两侧50 m范围内耕作层土壤和两侧作物会发生一定程度的重金属污染,路面灰尘是路侧土壤和蔬菜的潜在污染源. 相似文献
50.
海南新村湾海菖蒲TN和TP含量时空变化及其对营养负荷的响应 总被引:2,自引:0,他引:2
以海南新村湾海草床优势种之一的海菖蒲(Enhalus acoroides)为研究对象,于2005年7月、10月和2006年1月,分3个季度对网箱养殖区、中间过渡区和对照区海菖蒲不同组织的TN、TP含量的时空变化特征进行了研究,初步探讨了其对营养负荷的响应。结果表明:(1)新村湾海水和沉积物间隙水DIN含量,呈现出网箱养殖区中间过渡区对照区的显著趋势。(2)海菖蒲根、茎和叶在3个季度中的TN含量范围分别为:0.576%~1.544%、0.803%~2.480%和1.796%~3.200%;TP含量分别为:0.053%~0.175%、0.073%~0.197%和0.183%~0.413%。(3)海菖蒲不同组织TN、TP含量,均显示叶茎根的显著趋势;海菖蒲不同组织TN含量呈现秋、冬季夏季的趋势,TP含量随季节变化趋势各有不同。(4)海菖蒲根和叶的TN含量,有由网箱养殖区向对照区递减的趋势,与其所在样区海水和沉积物间隙水DIN含量呈显著正相关;海菖蒲TP含量,普遍显示出网箱养殖区比中间过渡区和对照区显著大的趋势,但与海水和间隙水PO4-P的含量没有明显的关系。(5)N/P计算结果表明,新村湾海菖蒲的生长主要受N的限制。 相似文献