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1.
关于中国水土保持监测的基本思路   总被引:5,自引:1,他引:4  
1水土保持监测的目的、意义和任务水土保持监测包括水土流失及其治理的监测。我国水土流失分布广泛,按侵蚀营力的不同,可分为水力侵蚀、重力侵蚀、冻融侵蚀和风力侵蚀四种类型。其中水蚀主要分布在山地丘陵区;风蚀主要分布在长城以北,其次在黄泛平原沙土区与滨海地带...  相似文献   

2.
开发建设项目水土保持监测是水土保持法赋予水行政主管部门的重要职责。随着我省经济建设的快速发展,资源开发、基础建设对区域生态环境的影响也越来越为社会各界所关注,水土保持监测成果已成为检查开发建设项目水土保持方案实施情况的重要依据。水土保持监测实施方案则是确定水土保持监测工作路线、方法的重要指导资料,监测方案的可行性与准确性直接影响着监测成果的质量。风水复合侵蚀是指风力、水力对同一侵蚀对象(区域)的共同作用和交替作用,即在水蚀的基础上发生风蚀或在风蚀的基础上发生水蚀。风水复合侵蚀类型区开发建设项目监测方法较为复杂,难度也较大。为此,以大庆油田热电厂"上大压小"扩建工程为例,简要分析风水复合侵蚀类型区水土保持监测实施方案内容、方法,以期为其他类似工程提供参考。  相似文献   

3.
风蚀水蚀交错带侵蚀能量特征   总被引:2,自引:0,他引:2  
该计算了黄土高原南北水力侵蚀区,风蚀水蚀交错带及风沙边缘区的风蚀能量、水蚀能量及地形附加侵蚀能量。结果表明:在风水蚀交错带,在降雨侵蚀能量的基础上,由于风蚀能量的迭加,加之地形附加侵蚀能量也较高,使风蚀水蚀交错带成为高原的高侵蚀能量环境区和潜在侵蚀强度较大的地区。随着向风  相似文献   

4.
1《中国水土保持科学》是中国科学技术协会主管、中国水土保持学会主办的综合性学术刊物。2003年创刊,双月刊,公开发行:主编王礼先教授。2004年进入中国科技核心期刊,2011年入选《中国科学引文数据库》本刊主要刊登水土保待科学理论和技术方面的研究成果,包括土壤水蚀、风蚀.重力侵浊以及山洪泥石流侵蚀规律,土壤侵蚀监测与预报,防治水土流失的农业、林业与工程措施及小流域综合治理技术,干旱地区土地退化机制与荒漠化综合防治技术,在水力、重力侵蚀混合作用下山地灾害发生机制与  相似文献   

5.
《中国水土保持科学》2013,11(3):F0003-F0003
1《中国水土保持科学》是中国科学技术协会主管、中国水土保持学会主办的综合性学术刊物。2003年创刊,双月刊,公开发行。主编王礼先教授。2004年进入中国科技核心期刊,2011年入选《中国科学引文数据库》。本刊主要刊登水土保持科学理论和技术方面的研究成果,包括土壤水蚀、风蚀、重力侵蚀以及山洪泥石流侵蚀规律,  相似文献   

6.
随着生产建设项目水土保持“强监管”的提出,宁夏需要根据区域水土流失特点,建立科学适用的生产建设项目监管体系。选取宁夏水土保持动态监测管理系统中已有数据和近5 a已验收项目数据,根据生产建设项目类型进行分类,分析不同水土保持分区中生产建设项目土壤侵蚀特点。结果表明:(1)现有数量最多的生产建设项目为其他类型项目,需要针对该类型项目进行细化管理,其次为加工制造类项目和公路工程,这三类占比分别为26%、12%和9%,生产建设项目主要分布在丘陵台地干旱草原风水蚀交错区和银川平原潜在风蚀区,占比分别达到65%和19%;(2)近5 a已验收项目类型最多的为其他类型项目,其次为公路工程和其他电力工程,占比分别为26%、17%和12%;(3)风力侵蚀区的项目较水力侵蚀区少,但风蚀区各类项目均易发生强烈及以上侵蚀,水蚀区露天非金属矿较易发生强烈及以上侵蚀。  相似文献   

7.
吉林省西部风蚀耕地侵蚀特征初探张利,修竹奇,刘艳军,刘明义(吉林省水土保持科学研究所,辽源136200)吉林省西部风蚀耕地面积较大,目前约有5910.9km2。风蚀耕地是吉林省重要的粮食和经济作物生产基地,长期的不断加剧的风蚀,导致作物产量逐年降低,...  相似文献   

8.
根据河北省第一次全国水利普查成果,对张承地区土壤侵蚀面积、类型、强度、水土保持效果进行了分析,得出如下结论:张承地区是河北水土流失最为严重的地区,土壤侵蚀面积排前三位的区(县)分别为围场县、丰宁县和康保县;水力侵蚀占主导地位,风力侵蚀集中分布在河北坝上地区;土壤侵蚀区可分为风蚀为主水蚀为辅区、风蚀水蚀交错区、水蚀为主风蚀为辅区和水蚀区4个分区;轻度侵蚀面积最大,中度侵蚀次之,强烈、极强烈、剧烈侵蚀面积较小,并逐级减少;1995—2011年水土流失面积呈现逐年减少的趋势,并根据坝上高原区、冀北山地区和冀西北黄土丘陵区的地貌类型特点,提出土壤侵蚀防治建议。  相似文献   

9.
神府矿区束鸡沟流域的侵蚀类型和强度研究   总被引:1,自引:0,他引:1  
束鸡沟流域属于典型的风蚀交错地区,风蚀分布普遍,水蚀主要分布在沟谷,风蚀,水蚀,重力侵蚀在空间上相互重叠,具有多种侵蚀营力复合侵蚀的特点,流域具有较大的潜在侵蚀能力,流域输沙量主要来自谷坡泻沙和沟蚀,占输沙总量的70%以上,控制侵蚀产沙的难度大,其关键是沟谷治理(包括坡面沟蚀)。  相似文献   

10.
六道沟流域有效水蚀风蚀能量及其特征研究   总被引:7,自引:0,他引:7  
神木县六道沟流域属于典型的水蚀风蚀交错带,该文是在流域5年观测资料的基础上,分析计算了土壤有效水蚀能量和风蚀能量以及年内分配特征,指出该地区从2-5月,11-12月地表裸露,气候干旱,风力强盛,有效风蚀能量表现最高,其中4-5月和11月是风蚀能量的高峰时期,同时,占流域面积40.4%的NW,N,S,E,S坡(8方位计)又是风力吹蚀和风积的主最要破面,是防治风蚀的重点部位,6-10月份,有效风蚀以胆低,风力不强,加之地面湿润,风蚀风积作用表现微弱,但有效水蚀能量高,并集中于7-8月份,形成水力侵蚀的高峰,这种水力与风力侵蚀能量在一年之中相互交替,促进的结果是该地区土壤侵蚀强烈的重要原因。  相似文献   

11.
低氮和干旱胁迫对富士和秦冠生长及氮素利用的影响   总被引:2,自引:2,他引:0  
【目的】以富士(Fuji)、 秦冠(Qinguan)嫁接在平邑甜茶(Malus hupehensis Rehd.)上的当年生盆栽苗为试验材料,采用砂培方法,研究了缺氮胁迫和干旱对富士和秦冠生长情况、 光合参数、 植株各部位氮磷钾含量及氮素利用效率的影响,分析比较了低氮干旱条件下富士和秦冠生长及氮素利用的差异,以期为果树生产高效肥水利用提供理论指导。【方法】试验共设四个处理: 正常氮正常水(ZZ)、 低氮正常水(DZ)、 正常氮干旱(ZG)、 低氮干旱(DG)。氮素和水分均设置两个水平,分别为正常氮(6 mmol/L NO-3-N)、 低氮(0.3 mmol/LNO-3-N)、 正常供水(保持盆中砂子相对含水量为饱和含水量的80%~85%)、 干旱处理(保持盆中砂子相对含水量为饱和含水量的60%~65%)。【结果】富士和秦冠的生物量(茎和叶)、 株高茎粗等生长指标以及光合速率、 气孔导度、 蒸腾速率均为正常氮正常水(ZZ)>低氮正常水(DZ)>正常氮干旱(ZG)>低氮干旱(DG),并且相对应处理下秦冠的以上指标均高于富士;正常供水下,缺氮处理使富士、 秦冠的根冠比比正常氮处理均有所增加,富士提高了2.05%,秦冠提高了22.40%。富士和秦冠的氮、 磷、 钾含量均表现出正常氮正常水(ZZ)>低氮正常水(DZ)>正常氮干旱(ZG)>低氮干旱(DG); 氮、 钾元素含量在植株各部位的分布顺序依次是叶>根>茎,磷元素则是根>叶>茎;光合氮素利用效率(PNUE)和氮素利用效率表现为秦冠处理之间差异极显著,富士处理之间差异不显著;秦冠的PNUE和NUE明显高于富士,在低氮正常水(DZ)处理下,秦冠氮肥利用率比富士高42.07%,在低氮干旱(DG)处理下高64.14%;低氮胁迫下富士和秦冠的NUE显著提高,并且秦冠提高的幅度高于富士。【结论】施用氮肥能够显著提高富士与秦冠的干物质量,同等水肥条件下,秦冠生长优于富士;水分亏缺会减少叶片对氮的吸收,干旱条件下适度增施氮肥,可提高果树的抗旱能力;低氮干旱胁迫下秦冠的生长指标、 光合指标及氮素利用效率指标均优于富士,表现出较强的抗低氮干旱胁迫的能力。  相似文献   

12.
Laser-induced breakdown spectroscopy (LIBS) is a new technique for the analysis of plant material. This study investigates the application of LIBS to pasture-based plant samples. The LIBS measurements were obtained from pelletized pasture samples (100 samples) that had been also analyzed by inductively coupled plasma–optical emission spectroscopy (ICP-OES) following microwave digestion for calibration and comparison purposes. Comparisons for elements sodium (Na), potassium (K), magnesium (Mg), calcium (Ca), manganese (Mn), iron (Fe), copper (Cu), zinc (Zn), boron (B), phosphorus (P), and sulfur (S) showed that LIBS could be used for almost all the standard profile total elements with concentrations down to low mg/kg levels (observed error of Na: 0.024 percent, K: 0.18 percent, Mg: 0.016 percent, Ca: 0.073 percent, P: 0.017 percent, Mn: 31 mg/kg, Fe: 150 mg/kg, Zn: 6.6 mg/kg, and B: 1.1 mg/kg). Elemental analysis at less than mg/kg levels was not possible using LIBS. The elements S and Cu were particularly difficult to analyze with reliability using LIBS at the concentration levels found in the plant samples. Replacing microwave digestion and subsequent ICP analysis with a direct analysis of dried plant samples using LIBS has the potential to improve the productivity and reduce the cost of testing.  相似文献   

13.
“Wicked” problems are those that are complex and that change when solutions are applied. Many conflicts in conservation fall into this category. The study approached the problem of how to constrain the apparent wickedness of a problem in the conservation management of a species by using simple empirical indicators to carry out iterative assessment of the risk to a population and to document how this risk evolves in relation to the addition of new data and the implementation of management actions. Effects of high levels of uncertainty within data and also concerning population structure were examined through stochastic simulation and by exploration of scenarios. Historical trends in the example used, the Steller sea lion, showed rapid declines in abundance in some regions during the 1980s. The current total population is 130,000-150,000 Steller sea lions through Alaska and British Columbia and this number has been stable since about 1990 in spite of regional differences in population dynamics. Regional differences in the sequence of changes in the number of pups and non-pups, suggested that an internal re-distribution of juveniles could have happened between 1980 and 1990. Current productivity also appears close to the long-term mean. Stochastic population projection using various scenarios showed that, based upon this history, the risk of extinction for the population has declined and is below reasonable thresholds for considering the population to be endangered. The trends in risk suggest that management actions taken since 1990 have probably been effective. Consequently, the conservation management objectives for the Steller sea lion are probably being met. The approach provides a mechanism, based upon experience and scenario analysis, for exploring future policy options and may help to constrain the debate amongst stakeholders about the cost-benefit trade-offs associated with different options.  相似文献   

14.
Nutrient distributions under no tillage (NT) compared with conventional disk-and-bed tillage (CT) management in the warm, humid region of the southeastern USA need to be assessed so that future placement, quantity, and type of fertilizers can be altered, if necessary, to efficiently match crop demands. We determined soil-profile distributions of pH, N, P, S, K, Ca, Mg, Na, Zn, Fe, Mn, and Cu to a depth of 0.9 m at the end of 8.5 years of continuous CT and NT management on a Weswood silty clay loam (fine, mixed, thermic Fluventic Ustochrept) in southcentral Texas. Most dramatic changes occurred within the 0–0.05 m depth, where soil under NT had lower pH, Fe, and Cu than under CT, but greater P, K, Zn, and Mn. Greater P and K under NT than under CT also occurred below the till-zone (0.15–0.3 m). At a depth of 0–0.3 m, soil under NT contained greater amounts of extractable P, K, Zn, Fe, Mn, and Cu than under CT. Nitrogen fertilization had little effect on nutrient distributions, except resulting in greater extractable K at 0–0.05 m and greater nitrate at 0–0.15 m. Few changes in soil-profile distributions were observed for extractable S, Ca, Mg, and Na. Long-term continuous use of NT on this fine-textured, high-fertility (except for N) soil had no apparent adverse effects on nutrient distributions relative to CT, but enhanced conservation and availability of P, K, Zn, Fe, Mn, and Cu near the soil surface where crop roots proliferate.  相似文献   

15.
正The Center for Agricultural Resources Research(CARR),the Institute of Genetics and Developmental Biology(IGDB),Chinese Academy of Sciences,invites applicants for several research group leader positions.CARR is one of the research organizations in Chinese Academy of Sciences(CAS).We seek nominations and applications from individuals who have expertise and a record of accomplishment in research areas related to ecology,agro-hydrology,  相似文献   

16.
The responses of tallgrass prairie plant communities and ecosystem processes to fire and grazing are well characterized. However, responses of invertebrate consumer groups, and particularly soil-dwelling organisms, to these disturbances are not well known. At Konza Prairie Biological Station, we sampled soil macroinvertebrates in 1994 and 1999 as part of a long-term experiment designed to examine the effects and interactions of annual fire, mowing, and fertilization (N and P) on prairie soil communities and processes. For nearly all taxa, in both years, responses were characterized by significant treatment interactions, but some general patterns were evident. Introduced European earthworms (Aporrectodea spp. and Octolasion spp.) were most abundant in plots where fire was excluded, and the proportion of the total earthworm community consisting of introduced earthworms was greater in unburned, unmowed, and fertilized plots. Nymphs of two Cicada genera were collected (Cicadetta spp. and Tibicen spp.). Cicadetta nymphs were more abundant in burned plots, but mowing reduced their abundance. Tibicen nymphs were collected almost exclusively from unburned plots. Treatment effects on herbivorous beetle larvae (Scarabaeidae, Elateridae, and Curculionidae) were variable, but nutrient additions (N or P) usually resulted in greater densities, whereas mowing usually resulted in lower densities. Our results suggest that departures from historical disturbance regimes (i.e. frequent fire and grazing) may render soils more susceptible to increased numbers of European earthworms, and that interactions between fire, aboveground biomass removal, and vegetation responses affect the structure and composition of invertebrate communities in tallgrass prairie soils.  相似文献   

17.
To evaluate the feasibility of long-term desert reforestation technology of mixed vegetation, cardon cactus (Pachycereus pringlei) seedlings from indoor and outdoor nurseries were planted in the field adjacent to one seedling of potential legume nurse trees: mesquite amargo (Prosopis articulata), yellow palo verde (Parkinsonia microphylla), and blue palo verde (Parkinsonia florida). Some of the planting holes were also supplemented with common dairy compost. Additionally, the combinations of legume tree–cactus were inoculated with either a consortium of desert arbuscular mycorrhizal (AM) fungi, plant growth promoting bacteria (PGPB; the diazotroph Azospirillum brasilense Cd, and the phosphate solubilizer Paenibacillus sp.), or a mixture of all. The field experiments were evaluated periodically during 30 months for survival and growth. Cardons reared in an outdoor screen house survived better in the field than those reared in a controlled growth chamber and hardened later outdoors. Association with any legume nurse tree increased survival and enhanced growth of untreated cardons. For cardons growing alone, application of either compost, AM fungi, and all the treatments combined increased survival. For these plants, no treatment affected plant growth during the first 3 months after transplanting. Later, all treatments, except for AM fungi, enhanced plant growth. However, only 2 years after transplanting the enhanced growth effect of AM fungi was also significant. In the presence of the legume nurse trees, transient positive effects on cardon growth were recorded. General evaluation after 30 months of cultivation showed that the treatments positively affected cardon growth when growing alone or in combination only with mesquite amargo but not with the other two legume trees. This study proposes that young legume trees have the capacity to enhance survival and growth of cardon cactus, depending on the legume cactus combination. Additional treatments such as compost or PGPB can either amplify the effect or else attenuate it.  相似文献   

18.
Abstract

A 3-year study was carried out to investigate quality parameters in 14 tree fruit and berry species grown in southern Norway. The species were blueberry, apple, aronia, sour cherry, sweet cherry, red raspberry, strawberry, blackcurrant, gooseberry, red currant and elderberry, harvested along with wild bilberry, cloudberry and lingonberry. Significant differences between species were identified for all quality parameters. The coefficient of variation between species was lowest for pH (12.5%), dry matter (18.9%) and soluble solids (25.3%), followed by titratable acids (59.3%), total phenolics (83.8%), antioxidant capacity FRAP (85.7%) and antiradical power by the DPPH-assay (97.8%), total monomeric anthocyanins (132%) and ascorbic acid (137%). Average coefficient of variation within species were lower and ranged from 4 (pH) to 62% (ascorbic acid). Only the FRAP values were significantly affected by harvesting year with lower levels in 2004 than in 2005 and 2006. There were significant interactions between species and harvesting year for dry matter, soluble solids, pH, ascorbic acid and FRAP. The results indicate generic ranges in composition within species independent upon growing location and climate, and the composition of the tree fruits and berries is not likely to deviate from these ranges. It is concluded that desirable composition of tree fruits and berries and their products should primarily be achieved by selection among species rather than searching fors broadened variation within individual species.  相似文献   

19.
Detailed karyotypes and 4C DNA amounts have been studied in five cultivars of Cajanus cajan and 20 species belonging to Cajanus, Rhynchosia, Dunbaria, Flemingia and Paracalyx. C. cajan shows intraspecific variability and its karyotype is most similar to that of C. cajanifolius (sect. Cajanus) in the morphology and number of satellite chromosomes and the lack of any correlation between chromosome size within the complement and asymmetry. Karyotypes of C. lineatus and C. sericeus belonging to sect. Atylia are similar with respect to maximum r-index and the ratio of longest and shortest chromosomes in their respective complements. C. acutifolius (sect. Frutocosa) is distinct in having a very low ratio (1.44) between the longest and the shortest chromosomes, while in C. albicans, C. goensis, C. scarabaeoides (sect. Cantharospermum) there is no chromosome pair with r-index >2.0. C. mollis and C. volubilis (sect. Volubilis) show similarity with regard to ratio between the longest and the shortest chromosomes and a distinct chromosome pair with an arm ratio of 2.7 and C. platycarpus is distinct (sect. Rhynchosoides) in having the smallest ratio (1.36) between the longest and the shortest chromosomes. 4C DNA amounts in Cajanus and Rhynchosia vary between 3.28 pg to 11.69 pg and 4.92 pg to 11.13 pg respectively, while in Dunbaria, Flemingia and Paracalyx these vary between 4.70 and 7:06 pg. In the genus Cajanus karyotypic features and 4C DNA amounts agree with the sectional classification and bring out a close relationship between C. cajan and C. cajanifolius. This is supported by studies based on seed protein patterns, isozyme analysis, trypsin and chymotrypsin inhibitor patterns, RFLP and RAPD data and crossability relationships. A clear relation between DNA amount and abnormalities effecting the extent of pairing and recombination in interspecific hybrids shows the importance of this study in developing future breeding programme involving C. cajan and its wild relatives that are of potential value.  相似文献   

20.
Several commercial fungicide seed treatments were evaluated for their possible effect on the survival of Bradyrhizobium japonicum on seeds and on the nodulation and yield of soybeans in a greenhouse and a field experiment. quinolate Pro (carbendazim and oxine copper), Vitavax 200FF (carboxin and thiram), and Monceren (pencycuron) had a small effect or no effect on the survival of B. japonicum and on the nodulation and yield of soybeans. They can thus be considered compatible with soybean seed inoculation. Germipro UFB (carbendazim and iprodione), Apron 35J (metalaxyl), and Tachigaren (hymexazol) decreased B. japonicum survival and the nodulation and yield of soybeans and thus cannot be considered compatible with soybean seed inoculation.  相似文献   

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