Agricultural drainage ditches help remove excess water from fields and provide habitat for wildlife. Drainage ditch management, which includes various forms of vegetation clearing and sediment dredging, can variably affect the ecological function of these systems. To determine whether ditch conditions following dredging/vegetation clearing management affected the survival, growth, and development of embryos and tadpoles of northern leopard frogs (Lithobates pipiens), we conducted three field studies using in situ cages over 2 years. We measured nutrients, pesticides, and other water quality properties in vegetated/unmanaged (i.e., no clearing or dredging) and newly cleared/dredged (i.e., treeless, then dredged), clay-bottomed drainage ditches in a river basin in Eastern Ontario, Canada. Nutrients, atrazine, and total neonicotinoid concentrations were generally lower at the cleared/dredged sites, whereas glyphosate was at higher concentrations. In contrast, water-quality variables measured in situ, particularly temperature, dissolved oxygen, and turbidity, tended to be higher in the cleared/dredged sites. Total phosphorous and total organic carbon concentrations at all sites were above the recommended limits for amphibian assays. No significant differences were detected in the survival, hatching success, or development of embryos among the ditch management treatments, but premature hatching was observed at one vegetated/unmanaged site where high specific conductivity may have been formative. We found the cleared/dredged sites supported earlier tadpole growth and development, likely as a result of the higher water temperatures. Increased temperature may have offset other growth/development stressors, such as those related to water chemistry. However, the long-term consequences of these differences on amphibian populations requires further study.

农业排水沟有助于从田间去除多余的水，并为野生动植物提供栖息地。排水沟管理（包括各种形式的植被清除和泥沙疏）可能会不同程度地影响这些系统的生态功能。为了确定疏dr /植被清理管理后的沟渠状况是否影响北部豹蛙（Lithobates pipiens）的胚胎和t的存活，生长和发育），我们在2年的时间内使用原位笼进行了三个野外研究。我们在安大略省东部流域的植被/未管理（即不进行清理或疏ed）和新清理/疏通（即先无树，然后疏ged），粘土底排水沟的环境中测量了养分，农药和其他水质属性，加拿大。在清理/疏red的地方，营养素，at去津和总新烟碱浓度通常较低，而草甘膦的浓度较高。相反，原地测量的水质变量，特别是温度，溶解氧和浊度，在已清理/疏red的地方往往较高。所有位点的总磷和总有机碳浓度均高于两栖动物分析的建议限值。在存活率，孵化成功率，沟管理处理中胚胎的发育或发育，但是在一个植被/非管理场所观察到过早的孵化，在该场所可能形成高比电导率。我们发现，由于水温升高，清理/挖出的土地为supported的生长和发育提供了支持。温度升高可能抵消了其他生长/发育应激源，例如与水化学有关的那些。但是，这些差异对两栖动物种群的长期影响尚需进一步研究。可能是由于较高的水温所致。温度升高可能抵消了其他生长/发育应激源，例如与水化学有关的那些。但是，这些差异对两栖动物种群的长期影响尚需进一步研究。可能是由于较高的水温所致。温度升高可能抵消了其他生长/发育应激源，例如与水化学有关的那些。但是，这些差异对两栖动物种群的长期影响尚需进一步研究。