Forage production and quality of 4 perennial grasses grown under and outside canopies of matureProsopis glandulosa Torr. var.glandulosa (mesquite)

Comparisons were made of dry matter production and forage quality of two coolseason grasses, Canada wildrye (Elymus canadensis L.), Virginia wildrye (Elymus virginicus L.), and two warm-season grasses, green panic (Panicum maximum var.trichoglume Eyles) and plains bristlegrass (Setaria leucopila Scribn. & Merr.), planted under and outside the canopies of mature honey mesquite (Prosopis glandulosa Torr. var.glandulosa). Green panic gave the greatest cumulative dry matter yield in both canopy (5120 kg ha^–1) and open (3370 kg ha^–1) locations, followed by plains bristlegrass under mesquite (1130 kg ha^–1) and in the open (570 kg ha^–1). One-time yields from Canada wildrye and Virginia wildrye, under and outside mesquite canopy, were 247 and 329 kg ha^–1, and 272 and 268 kg ha^–1, respectively. Dry matter production of green panic (p=0.001) and plains bristlegrass (p=0.026) was greater under mesquite only for the first of four harvests, although both warm-season grasses exhibited a trend for greater production under mesquite than in the open. Average nitrogen content of green panic was greater (p=0.0004) under mesquite than in the open, while plains bristlegrass exhibited a trend for greater crude protein content in the open than under mesquite. Overall, moisture content of the warm-season grasses was greater (p=0.0001) under mesquite than in the open, while Virginia wildrye was more (p=0.002) succulent under mesquite than in the open. Averagein-vitro dry matter digestibility of warm-season grasses was almost significantly greater (p=0.0501) in the open than under mesquite. Canopy soils contained significantly more organic C (p=0.0004) and total N (p=0.0001) than open soils, with differences of 8.3 Mg organic C ha^–1 and 1.3 Mg total N ha^–1. Correlations indicated that soil fertility was more limiting to grass production than light intensity.     

黄泛平原风沙区的水土流失及其治理开发探讨

由于人们对于平原风沙区的水土流失不如对山丘区的水土流失认识深刻,为了纠正这种偏见,本文以黄泛平原风沙区为例,从侵蚀方式、侵蚀程度及危害的严重性加以分析,以证明鲁西北黄泛平原已被联合国环境保护组织列为高度荒漠化危险区.同时对平原风沙区提出了治理开发对策以及选定的开发试区实施了多种治理措施,效益明显,使试区农民走上了脱贫致富的道路,已成为黄泛平原沙区治理开发的典范.     

黄淮海平原棉麦共生期间棉田土壤温度效应的研究

4年连续研究揭示,黄淮海棉区套作棉田全共生期45d,4-2式地温低1.3～2.3℃d#+（-1）,3-1式地温低1.8～3.4℃d#+（-1）,处于低热量状态,导致棉花前期生长滞后10～15d。两熟套作棉田各层次温度比一熟棉田降低4.8%～15.4%,其中3-1式棉行温度低于4-2式,4-2式南棉行低于北棉行。在两熟套作条件下,3-1式配置方式地膜覆盖的增温效应比4-2式削弱更多;同是地膜覆盖,宽覆盖比窄覆盖的增温效应更为明显。结果表明,黄淮海棉区棉麦两熟采用4-2垄作和地膜覆盖能减轻或缓解共生期间棉田的低热量胁迫,促进棉田早发早熟。     

Yield and water productivity of rice as affected by time of transplanting in Punjab, India

Early planting of rice crop during the period of peak evaporative demand results in substantial mining of ground water and threats the sustainability of rice production in Punjab, northwest India. In order to increase yield and water productivity, arrest the mining of ground water, and achieve sustainability of rice production, there is need to adopt water-saving management practices. The present investigation in the Indian Punjab was aimed at investigating the effect of date of transplanting in four rice cultivars varying in growth duration (short-duration RH-257 and PR-115, and medium-duration PR-113 and PAU-201) on yield and water productivity. Delaying in transplanting from 15 June to 25 June or 5 July resulted in reduction in mean grain yield of the four cultivars by 7.2% and 15.9%, respectively. PAU-201, a photoperiod-sensitive cultivar, had higher mean grain yield (7.8 t ha⁻¹) by 14.1%, 12.8% and 11.5% over the photoperiod-insensitive cultivars, PR-113, PR-115 and RH-257, respectively. Irrespective of transplanting dates, short-duration cultivars, RH-257 and PR-115, respectively, resulted in 18.9% and 16.6% saving of water, as compared to medium-duration cultivar PR-113. With delayed transplanting after 15 June, both yield and water productivity decreased for all photoperiod insensitive cultivars, but yields remained statistically similar and water productivity greater for a photoperiod sensitive cultivar. Mean irrigation water productivity (WP_I) was highest for 15 June transplanting (0.66 kg m⁻³) and lowest for 5 July transplanting (0.57 kg m⁻³), and was highest for RH-257 (0.68 kg m⁻³) and lowest for PR-113 (0.50 kg m⁻³). Total water productivity (WP_I+R; irrigation plus rainfall) decreased by 9.1% for 5 July transplanting compared with 15 June transplanting, and was highest for RH-257 (0.49 kg m⁻³) and lowest for PR-113 (0.38 kg m⁻³). Real crop water productivity (WP_ET) of the photoperiod insensitive cultivars decreased (1.10-1.40 kg m⁻³), but that of a photoperiod sensitive cultivar increased (1.63 kg m⁻³), with delayed transplanting. We conclude that substantial amount of water can be saved and yield increased by transplanting short-duration cultivars during the period of peak evaporative demand, or water saved and yield maintained by transplanting a photoperiod-sensitive cultivar late in the season when the evaporative demand is low.     

Identifying potential causes of fish declines through local ecological knowledge of fishers in the Ganga River,eastern Bihar,India

Local ecological knowledge (LEK) can offer insights into fisheries management by describing long‐term changes that are difficult to unravel in data‐poor river‐floodplain fisheries. LEK is derived from complex interactions between fishers’ observations of environmental change and their institutional capacities to manage fisheries. Hence, it is important to understand where and how LEK and formal scientific studies on fish species’ decline could complement each other. In this paper, the causes of decline of 58 fish and two shrimp taxa were identified from LEK data (1999–2019) obtained from river–floodplain fisheries of the Gangetic plains (Bihar, India). Qualitative analyses of LEK were used to generate species‐specific hypotheses and historical insights on their declines. Destructive fishing, overfishing and the Farakka barrage were cited by fishers as the major causes of declines. Potential reasons for these perceptions were explored in relation to fishers’ experiences of conflicts in the region over fishing rights and access.     

中原经济区现代农业主体功能区划及其发展

农业主体功能区划建设的核心在于强化农业发展的空间管治。根据主体功能区思想及中原经济区农业发展实践划分的五个功能区,承载着现代农业的社会、经济、生态、文化等不同功能,现代农业发展水平趋异。五大功能区中,郑州都市农业区的技术装备程度、中原城市群外围农业区的机械化和化学化以及黄淮海农业特区的水利化都居于较高水平,而西南部养护与防护区的农业投入水平总体偏低。针对各功能区分类指导、突出重点、梯次推进,是中原经济区现代农业协调发展的关键。     

河南省高职院校参与农村剩余劳动力就业·创业培训研究

立足于河南省的基本省情,对河南省高职院校参与农村剩余劳动力就业、创业培训的重大意义、存在的问题和对策进行了研究。     

推进北方平原地区秸秆综合利用的思考

北方平原地区可耕地比重大、人均耕地少、土质肥沃,是我国重要的粮食基地,主要种植玉米、高粱、小麦、水稻等农作物,秸秆产量非常大。但是,秸秆综合利用方面总体水平仍然较低,效益较差,甚至就地焚烧的现象在各地还大量存在,不仅造成资源浪费、环境污染,还严重威胁交通运输安全。因此,加强秸秆综合利用的研究,努力推进秸秆的资源化、商品化,实现变废为宝,是一个紧迫而重要的现实课题。     

中原经济区背景下高校英语师资队伍建设探析

在中原经济区建设的背景下,河南高校英语师资队伍存在着一些亟待解决的问题,应当通过制定建设规划、强化业务培训、利用多媒体教学手段、建立绩效考核机制等途径加强高校英语师资队伍建设。     

Hematologic and serum biochemical reference values for the wild Spectacled Caiman, Caiman crocodilus crocodilus, from the Venezuelan plains

Background: Commercial farming of Caiman crocodilus crocodilus has had an impact on the use of this species for meat consumption and the leather industry. Spectacled Caimans comprise part of the South American plains biodiversity. Misinterpretation of laboratory data is a risk owing to the limited hematologic and serum biochemical values available for this species. Objective: The aim of this study was to determine hematologic and serum biochemical values for wild Spectacled Caimans from the Venezuelan plains. Methods: Blood samples were collected form the caudal tail vein of 100 Spectacled Caimans (40 males and 60 females) from the plains located in the State of Apure. Values for RBC count, PCV, hemoglobin concentration, WBC absolute and differential counts, and thrombocyte counts were obtained using manual methods, and RBC indices were calculated. Serum biochemical analysis included measurement of alkaline phosphatase, alanine aminotransferase, aspartate aminotransferase, and creatine kinase activities and concentrations of total protein and albumin. Comparisons between sexes were analyzed using the Mann–Whitney test. Results: Reference values for wild Spectacled Caimans were determined. Minor differences in hematologic values, particularly for RBC counts, were found compared with previously published values for this species. Serum biochemical values were similar to those available for other crocodilians. There were no significant differences between males and females. Conclusions: Minor differences between the values obtained for wild Spectacled Caimans and those previously published for this species may be related to differences in methodology and environmental conditions. Availability of hematologic and serum biochemical reference values will be useful for accurate diagnosis and management of disease in this species.