陕北淤地坝建设现状调查分析

淤地坝建设在陕北有着悠久的历史，截至１９８９年底止，共建成淤地坝３１７９７座，其中有骨干工程５８座，大型８３６座，中型５６００座，小型２５３０３座，总库容３９４９２８万ｍ３，已拦泥２９８１０９万ｍ３，共可淤地４９３８６ｈｍ２，已淤地４３２８９ｈｍ２，坝地利用率６９．８％。大中型和骨干工程控制流域面积１７５６２．５７ｋｍ２，占全区水土流失面积的２６．７％。由于缺乏合理的规划设计、施工质量低、运行年限超过设计淤积年限等原因，有７５．８％的淤地坝成为病险坝。应加强淤地坝建设的科学研究，加强管护、抓紧整修加固配套。     

水土保持是改善库区环境、安置三峡移民的根本

三峡库区的现有环境已成失衡态势，三峡工程上马后对库区环境影响较大的是随淹没而来的移民和搬迁。改善库区环境状况、解决移民安置的根本出路为搞好水土保持，扩大环境容量，抓好预防监督保护和以坡改梯及经济林果、林草建设为重点的水土保持综合治理。当前应紧紧抓住三峡工程开工这个机遇，在已有的“长治”工程基础上加优、扩大开发性防治，再辅之以其它政策性措施，库区环境和移民安置可以得到根本解决。     

依法防治水土流失让“三湘四水”更好地造福人民

湖南省山丘区面积占总面积的８０％，水土流失比较严重。解放后虽累计治理了１．７万ｋｍ２，但由于边治理、边破坏．８０年代末仍有水土流失面积４．７万ｋｍ２，年土壤侵蚀量１．５７亿ｔ，造成严重危害。近几年来，认真贯彻水土保持法，依法防治水土流失，大搞荒山造林、封禁治理和小流域综合治理开发，取得了显著成效。要进一步加强领导，建立健全水保监督执法体系，多渠道增加投入，加快水土流失防治步伐。     

Development of biomarkers inAporrectodea caliginosa andLumbricus rubellus for detecting exposure to benzo[a]pyrene

Objectives and Methods. The sensitivity of two biomarkers, the neutral red retention assay (NRRA) and cytochrome P450 were evaluated in the earthwormAporrectodea caliginosa for their potential to detect exposure to benzo[a]pyrene (BaP). Cytochrome P450 was also evaluated in the earthwormLumbricus rubellus, and measured using the substrate ethoxycoumarin. Optimal assay conditions (pH, and temperature) were determined, followed by exposure of earthworms to 20 mg/kg BaP (a typical concentration at contaminated sites in New Zealand). Ethoxycoumarin-O-dealkylase (ECOD) activity was measured after 7, 14, and 21 days exposure. The NRRA was evaluated in earthworms exposed to 0.2, 20, and 100 mg BaP/kg, and biomarker responses were compared with effects on body weight. Results and Discussion Benzo[a]pyrene failed to induce ECOD activity in either earthworm species, and therefore it is not useful as a biomarker of BaP exposure and was not evaluated further. In all cases, the NRRA was significantly affected in the absence of any effects on earthworm body weight, indicating that this assay can detect exposure to BaP at a range of concentrations comparable to those found at contaminated sites. The NRRA should be linked to reproductive endpoints, then it can be used as an early warning indicator of adverse effects. Establishing biomarker stability under environmental conditions is an important step in biomarker development. Therefore, the effects of soil type (sandy soil, silt loam, and a clay soil), moisture content (15–30%), and temperature (5–20°) on the NRRA were determined. In all cases, there was no effect on the NRRA, indicating that this assay is very stable under varying environmental conditions. Conclusion and Outlook In conclusion, cytochrome P450 activity does not appear to be a useful indicator of PAH exposure in eitherA. caliginosa or L.rubellus, and due to the inherently low activity, it is not suitable as a routine biomarker for detecting environmental contamination by these compounds. In contrast, the NRRA in the earthworm A.caliginosa is a promising indicator of PAH exposure at the concentrations likely to be found in contaminated sites in New Zealand, and therefore has potential for evaluating these contaminated sites. If the NRRA can be linked to ecologically important life-cycle endpoints, such as reproduction, then it could be used as an early warning indicator of adverse effects at contaminated sites, i.e., by measuring biomarker responses in earthworms from a ‘contaminated area’ and comparing these with earthworms from a matched control area.     

加强自身建设 搞好山区水利水保工作

加强自身建设搞好山区水利水保工作山东省枣庄市山亭区水泉乡水利水保站（２７７２１５）我们水泉乡地处沂蒙山区西南部，全乡总面积１０７．５平方公里，是个纯山区乡。自党的十一届三中全会以来，我们水利水保站在乡党委、政府的直接领导下，立足山区实际，深化改革，同...     

穆棱县拍卖“五荒”加快水土流失治理的调查报告

穆棱县拍卖“五荒”加快水土流失治理的调查报告郭廷辅，佟伟力，刘家仁，庞志桐（北京水利部水土保持司，１００７６１）（黑龙江省水利厅）编者按：拍卖“五荒”（荒山、荒地、荒滩、荒草、荒水）使用权，加快水土流失治理，挖掘水土资源的生产潜力，既是农村深化改革的...     

城乡交错带居民点整理潜力研究--以山西省太原市晋源区为例

居民点整理是缓解城乡交错带耕地压力、优化土地资源配置、理顺用地关系的主要途径之一,而居民点整理潜力评价是居民点整理的一项基础性研究工作.该文以山西省太原市晋源区为例,探讨了城乡交错带居民点整理模式、潜力分析、等级划分以及效益分析等,为城乡交错带居民点整理的潜力评价提供方法借鉴.     

流域治理的可持续发展标准

流域治理的可持续发展标准王礼先（北京林业大学水土保持学院，１０００８３）一、流域治理的实质流域治理（ｗａｔｅｒｓｈｅｄＭａｎａｇｅｍｅｎｔ），又称流域管理、流域经营、集水区经营，其概念是：为了充分发挥水土资源的生态效益、经济效益、社会效益，以流域为单...     

五味子的深层次综合开发研究

五味子的深层次综合开发研究孔四新，贾绪初，李延福（河南省济源市水土保持研究所，４５４６５０）五味子，一种盛产于我国广大山区的野果，属木兰科多年生木质藤本植物，因其果具有酸、甜、苦、辛、咸五昧故而得名，历史上多作药用。近年来，这一野生植物的营养保健价值...     

黄河中游水土流失区基本农田建设浅议

黄河中游水土流失区基本农田建设浅议高荣乐（黄委会黄河上中游管理局，西安７１００４３）黄河中游地区农业生态环境的主要特征可以概括为三个方面：一是以山丘地貌为主，梁峁起伏，沟壑纵横。在已开垦的１８６７万ｈｍ２农耕地中，处于平原区的不足２０％，其余均分布于...